export type AtlasCategory =
  | "Degenerative"
  | "Traumatic"
  | "Inflammatory"
  | "Congenital"
  | "Infectious"
  | "Neoplastic";

export type AtlasCondition = {
  slug: string;
  name: string;
  regionSlug: string;
  category: AtlasCategory;
  summary: string;
  sections: {
    overview: string;
    epidemiology: string;
    symptoms: string;
    imaging: string;
    classification: string;
    management: string;
    outcomes: string;
  };
  references?: string[];
};

export const conditions: AtlasCondition[] = [
  // ---------------- KNEE ----------------
  {
    slug: "acl-tear",
    name: "Anterior Cruciate Ligament Tear",
    regionSlug: "knee",
    category: "Traumatic",
    summary:
      "A ligamentous disruption most often sustained during pivoting or deceleration in sport, producing rotational instability of the knee.",
    sections: {
      overview:
        "The anterior cruciate ligament is the primary restraint to anterior translation of the tibia on the femur and a secondary restraint to internal rotation. Disruption typically occurs through a non-contact pivoting mechanism with the foot planted and the knee near extension, although contact injuries are also common in collision sport. A haemarthrosis develops within hours in the majority of cases, reflecting bleeding from the torn ligament and frequently associated chondral or meniscal injury.",
      epidemiology:
        "Estimated incidence in the general population is 30 to 78 per 100,000 person-years, with young athletes in pivoting sports carrying several-fold higher risk. Female athletes have a two- to eight-fold higher rate than males in comparable sports, attributed to differences in neuromuscular control, limb alignment, hormonal environment, and notch geometry. Peak age is between 15 and 25 years.",
      symptoms:
        "Patients typically report a sudden pop or shift, rapid swelling, and inability to continue activity. On examination the Lachman test, anterior drawer, and pivot shift are the principal clinical tests, of which the Lachman is the most sensitive for acute injury. Persistent rotational instability, episodes of giving way on cutting, and apprehension with pivoting characterise the chronic phase.",
      imaging:
        "Plain radiographs should be obtained to exclude a Segond fracture, tibial spine avulsion, or occult osteochondral injury. MRI is the imaging standard, with sensitivity and specificity above 90 percent for complete tears, and adds essential information on meniscal tears, bone bruising, collateral ligaments, and articular cartilage. Kissing contusions of the lateral femoral condyle and posterolateral tibial plateau are a highly specific indirect sign.",
      classification:
        "Tears are classified anatomically (proximal avulsion, midsubstance, distal) and by completeness (partial versus complete). Functional classification uses the IKDC grading for laxity. Associated injury patterns, notably the O'Donoghue unhappy triad of ACL, MCL, and medial meniscus, remain clinically relevant although recent data implicate the lateral meniscus more frequently.",
      management:
        "Initial management is a course of rest, cryotherapy, and progressive rehabilitation to restore range of motion and quadriceps control. Active patients and those with instability on activities of daily living are typically offered arthroscopic reconstruction using bone-patellar-tendon-bone, hamstring, or quadriceps tendon autograft; allograft is reserved for older or revision cases. Graft choice, fixation method, and the role of lateral extra-articular tenodesis are active areas of trial evidence.",
      outcomes:
        "Return-to-sport rates after reconstruction approach 65 percent at preinjury level, with re-rupture rates of 5 to 10 percent on the ipsilateral side and similar rates on the contralateral knee within two years. Radiographic osteoarthritis is increased at 10 to 20 years regardless of treatment, particularly when concomitant meniscal injury is present. Structured return-to-sport criteria reduce reinjury risk.",
    },
    references: [
      "Musahl V, Karlsson J. Anterior Cruciate Ligament Tear. N Engl J Med. 2019;380(24):2341-2348.",
      "Beynnon BD et al. Treatment of ACL injuries, current concepts. Am J Sports Med. 2005;33(10):1579-1602.",
    ],
  },
  {
    slug: "meniscal-tear",
    name: "Meniscal Tear",
    regionSlug: "knee",
    category: "Traumatic",
    summary:
      "Injury to the medial or lateral fibrocartilaginous meniscus, ranging from acute sport-related tears in young patients to degenerative tears in mid-life.",
    sections: {
      overview:
        "The menisci distribute load, stabilise the joint, and contribute to lubrication and proprioception. Tears are broadly acute traumatic, typically twisting injuries in young active patients, or degenerative, in which age-related collagen disorganisation predisposes the tissue to failure under physiological loads. The medial meniscus is more commonly torn than the lateral because of its relative immobility.",
      epidemiology:
        "Annual incidence is approximately 60 to 70 per 100,000. Traumatic tears peak between ages 20 and 30 with a male predominance; degenerative tears rise sharply after age 50 and are present in nearly a third of asymptomatic adults over 60 on MRI. Concomitant ACL rupture is seen in up to half of acute traumatic tears.",
      symptoms:
        "Patients report joint line pain, mechanical symptoms (catching, locking), and effusion. McMurray, Thessaly, and joint line tenderness tests are commonly used; none is individually definitive and clinical diagnosis is strengthened by combining findings with history and imaging.",
      imaging:
        "MRI is the standard, demonstrating altered signal reaching the meniscal surface in a vertical, horizontal, oblique, radial, or complex pattern. Displaced bucket-handle fragments produce the classic double PCL or fragment-in-notch sign. Incidental asymptomatic tears are common beyond middle age and must be interpreted in clinical context.",
      classification:
        "Anatomical classification describes tear morphology (longitudinal, horizontal, radial, flap, bucket-handle, complex, root) and zone (red-red, red-white, white-white by vascularity). Root tears and radial tears of the lateral meniscus have the greatest biomechanical consequence, functionally equivalent to meniscectomy.",
      management:
        "Stable, non-displaced tears and most degenerative tears are managed non-operatively with physiotherapy and load modification; high-quality trial evidence (METEOR, FIDELITY) shows no benefit of arthroscopic partial meniscectomy over structured rehabilitation for most degenerative tears. Repairable tears in the vascular zone, root tears, and displaced bucket-handle tears warrant arthroscopic repair where possible, as meniscal preservation delays arthritis.",
      outcomes:
        "Outcomes after repair are excellent in young patients with peripheral tears, with healing rates above 80 percent. Partial meniscectomy relieves mechanical symptoms but accelerates compartmental osteoarthritis, particularly after lateral meniscectomy. Root repair, when performed early, reduces the subsequent rate of arthroplasty.",
    },
  },
  {
    slug: "knee-osteoarthritis",
    name: "Knee Osteoarthritis",
    regionSlug: "knee",
    category: "Degenerative",
    summary:
      "Progressive loss of articular cartilage with associated subchondral bone, capsular, and periarticular changes, producing pain, stiffness, and functional decline.",
    sections: {
      overview:
        "Knee osteoarthritis is a whole-joint disease involving articular cartilage loss, subchondral bone remodelling, meniscal degeneration, osteophyte formation, and low-grade synovitis. It is the leading cause of lower-limb disability in older adults and a major driver of orthopaedic surgical volume worldwide.",
      epidemiology:
        "Radiographic knee OA is present in 19 percent of adults over 45 in Western populations, with symptomatic disease in 7 percent. Risk factors include age, female sex, obesity, prior meniscal or ligamentous injury, occupational kneeling, and malalignment. The disease accounts for around 2 percent of global years lived with disability.",
      symptoms:
        "Activity-related pain, morning stiffness of short duration, crepitus, and progressive functional limitation are characteristic. Rest and night pain indicate advanced disease. Examination reveals effusion, tenderness, reduced range, and often varus deformity with medial compartment disease.",
      imaging:
        "Weight-bearing AP, lateral, skyline, and Rosenberg views are the radiographic standard, demonstrating joint space narrowing, osteophytes, subchondral sclerosis, and cysts. MRI is reserved for evaluation of pain out of proportion to radiographs, suspected osteonecrosis, or mechanical symptoms.",
      classification:
        "The Kellgren-Lawrence grading (0-4) is the most widely used radiographic system. Ahlbäck and OARSI atlas systems offer finer compartmental detail. Compartment-specific (medial, lateral, patellofemoral) description guides surgical planning.",
      management:
        "First-line treatment is education, weight loss, exercise therapy, and simple analgesia including topical NSAIDs. Intra-articular corticosteroid injections give short-term relief; viscosupplementation evidence remains mixed. Joint-preserving surgery (osteotomy, unicompartmental arthroplasty) is offered for focal disease in the young active patient. Total knee arthroplasty is the definitive treatment for end-stage tricompartmental disease.",
      outcomes:
        "Total knee arthroplasty achieves 80 to 90 percent patient satisfaction with implant survivorship above 90 percent at 15 years in contemporary registries. Around 20 percent of patients report persistent pain, and careful patient selection, shared decision making, and expectation setting remain central.",
    },
  },
  {
    slug: "patellar-dislocation",
    name: "Patellar Dislocation",
    regionSlug: "knee",
    category: "Traumatic",
    summary:
      "Lateral displacement of the patella from the trochlear groove, usually after a twisting injury, with rupture of the medial patellofemoral ligament.",
    sections: {
      overview:
        "Acute lateral patellar dislocation typically occurs when a valgus and external rotation force is applied to a flexing knee. The medial patellofemoral ligament (MPFL), the primary restraint against lateral translation, is disrupted in over 90 percent of first-time dislocations. Anatomical risk factors (trochlear dysplasia, patella alta, increased TT-TG distance, valgus alignment) predispose to recurrence.",
      epidemiology:
        "Incidence is approximately 5 to 7 per 100,000 overall, rising to 29 per 100,000 in the 10 to 17 year age band. Adolescent females are disproportionately affected. After a first episode, recurrence rates range from 15 to 44 percent and are higher in the skeletally immature and in those with anatomical risk factors.",
      symptoms:
        "Patients describe the patella going out of place, often with spontaneous relocation on knee extension. Immediate haemarthrosis, medial tenderness, apprehension on lateral translation, and a positive J-sign on active extension are typical. Osteochondral fragments produce mechanical symptoms.",
      imaging:
        "Radiographs (AP, lateral, skyline) assess trochlear depth, patellar height, and osteochondral fracture. MRI detects MPFL rupture, osteochondral injury of the medial patella and lateral femoral condyle, and joint effusion. CT is used to quantify TT-TG distance and trochlear morphology when surgical correction is considered.",
      classification:
        "Dejour's classification of trochlear dysplasia (A to D) guides surgical decision making. Risk stratification tools such as the Patellar Instability Severity Score combine anatomical risk factors to predict recurrence.",
      management:
        "First-time dislocation without loose body is generally managed with a short period of immobilisation followed by physiotherapy emphasising vastus medialis and hip control. Displaced osteochondral fragments require arthroscopic or open fixation. Recurrent instability is treated with MPFL reconstruction, often combined with tibial tubercle osteotomy or trochleoplasty where anatomical abnormalities are significant.",
      outcomes:
        "Isolated MPFL reconstruction gives recurrence rates below 5 percent in appropriately selected patients. Outcomes are less favourable with uncorrected trochlear dysplasia or elevated TT-TG distance, underscoring the importance of addressing all contributors to instability.",
    },
  },
  // ---------------- HIP ----------------
  {
    slug: "hip-osteoarthritis",
    name: "Hip Osteoarthritis",
    regionSlug: "hip",
    category: "Degenerative",
    summary:
      "Degenerative cartilage loss in the acetabulofemoral joint producing groin pain, stiffness, and progressive functional impairment.",
    sections: {
      overview:
        "Hip osteoarthritis is the end result of a spectrum of mechanical, metabolic, and inflammatory insults to the joint. Primary disease is idiopathic; secondary causes include dysplasia, femoroacetabular impingement, avascular necrosis, trauma, and inflammatory arthropathy. The hip is the second most commonly replaced large joint worldwide.",
      epidemiology:
        "Symptomatic hip OA affects around 10 percent of adults over 55 in Northern Europe, with higher radiographic rates. Total hip arthroplasty incidence in high-income registries exceeds 200 per 100,000 per year. Age, obesity, occupational loading, and prior hip disease are leading risk factors.",
      symptoms:
        "Groin pain that radiates to the anterior thigh and knee is the cardinal symptom. Patients describe stiffness after rest, difficulty putting on shoes and socks, and an antalgic or Trendelenburg gait. Internal rotation in flexion is lost early and is a reliable examination finding.",
      imaging:
        "Standing AP pelvis and lateral hip radiographs are the standard, showing joint space narrowing (typically superolateral), subchondral sclerosis, osteophytes, and cystic change. MRI and CT are reserved for differential diagnosis or preoperative planning; MRI is essential when osteonecrosis or occult fracture is suspected.",
      classification:
        "Tönnis grading (0-3) is commonly used. The Croft and Kellgren-Lawrence systems are alternatives. Preservation of the superior joint space distinguishes early disease where joint-preserving surgery may be considered.",
      management:
        "Conservative management comprises education, weight control, graded exercise, and analgesia. Intra-articular injections have limited role and may accelerate cartilage loss with repeated use. Total hip arthroplasty transforms function and quality of life in end-stage disease and is considered among the most successful interventions in modern medicine. Resurfacing and joint-preserving osteotomies have narrow indications.",
      outcomes:
        "Total hip arthroplasty achieves >95 percent implant survivorship at 10 years and >80 percent at 20 years in registry data. Patient-reported outcomes show large, durable improvements in pain and function. Periprosthetic infection, dislocation, and aseptic loosening remain the principal modes of failure.",
    },
  },
  {
    slug: "femoroacetabular-impingement",
    name: "Femoroacetabular Impingement",
    regionSlug: "hip",
    category: "Degenerative",
    summary:
      "Abnormal morphological contact between the proximal femur and acetabular rim during hip motion, implicated as a precursor of premature osteoarthritis.",
    sections: {
      overview:
        "Femoroacetabular impingement (FAI) syndrome describes painful hip motion resulting from abnormal morphology of the femoral head-neck junction (cam), the acetabular rim (pincer), or both. Repetitive impingement causes labral tears and chondral delamination, particularly in the anterosuperior quadrant of the acetabulum, and is increasingly recognised as a cause of early-onset hip osteoarthritis.",
      epidemiology:
        "Cam morphology is present in up to a quarter of asymptomatic young adults and is more common in males and athletes whose hips undergo high loads during skeletal maturation (football, ice hockey). Pincer morphology is more common in females. Symptomatic FAI presents most often between ages 20 and 40.",
      symptoms:
        "Activity-related groin pain, a clicking or catching sensation, and difficulty with deep flexion activities (sitting, squatting, tying shoelaces) are typical. The anterior impingement test (flexion-adduction-internal rotation) reproduces symptoms in most cases but is not specific.",
      imaging:
        "Standing AP pelvis and Dunn lateral or cross-table lateral radiographs demonstrate cam lesions (measured by alpha angle), acetabular overcoverage, retroversion (crossover sign), and secondary signs of chondral damage. MR arthrography is the standard for assessing labral and chondral pathology prior to surgical intervention.",
      classification:
        "Traditionally classified as cam, pincer, or mixed. The Warwick Agreement defined FAI syndrome as the triad of symptoms, clinical signs, and imaging findings; isolated radiographic morphology in an asymptomatic individual does not constitute disease.",
      management:
        "Structured physiotherapy targeting hip muscle strength, motion, and movement re-education is first line. Arthroscopic osteochondroplasty with labral repair is indicated for symptoms refractory to conservative care in patients without advanced arthritis. The FASHIoN and UK FASHIoN trials demonstrated superiority of arthroscopy over physiotherapy alone in selected cohorts.",
      outcomes:
        "Most young patients return to preinjury activities after arthroscopic surgery, with improvements in iHOT and NAHS scores sustained at five years. Outcomes are worse with Tönnis grade 2 or higher arthritis, older age, and longer symptom duration, reinforcing the importance of early recognition.",
    },
  },
  {
    slug: "developmental-dysplasia-hip",
    name: "Developmental Dysplasia of the Hip",
    regionSlug: "hip",
    category: "Congenital",
    summary:
      "A spectrum of abnormal acetabular and femoral development ranging from mild instability in infancy to frank dislocation and adult dysplastic arthritis.",
    sections: {
      overview:
        "Developmental dysplasia of the hip (DDH) encompasses a continuum from mild acetabular shallowness to complete dislocation. Undetected, DDH is the leading identifiable cause of premature hip osteoarthritis in young adults, particularly women. Early detection and treatment give excellent outcomes; delayed diagnosis complicates management significantly.",
      epidemiology:
        "Neonatal instability affects 1 to 3 per 100 infants; true dislocation is rarer at about 1 to 2 per 1000 live births. Risk factors include female sex, first pregnancy, breech presentation, family history, and oligohydramnios. Swaddling practices and genetic factors contribute to geographical variation.",
      symptoms:
        "In the neonate, Ortolani and Barlow tests detect instability. Beyond three months, limitation of abduction, asymmetric thigh folds, Galeazzi sign, and limp in the ambulant child become predominant. Adolescents and adults with residual dysplasia present with activity-related groin or lateral hip pain and labral tears.",
      imaging:
        "Ultrasound is the standard in infants under six months (Graf classification). After acetabular ossification, plain radiographs measuring acetabular index, centre-edge angle, and Shenton's line are used. CT or MRI may be needed before reduction in older children and for surgical planning in adolescents and adults.",
      classification:
        "Graf (ultrasound): I normal, IIa/b physiologic immaturity, IIc critical, D decentring, III/IV dislocated. Tönnis and IHDI classifications describe severity on plain radiographs in older children.",
      management:
        "Neonatal instability is treated with a Pavlik harness worn for 6 to 12 weeks with ultrasound monitoring. Failure or late presentation may require closed or open reduction and spica casting, often combined with pelvic or femoral osteotomies. Residual adult dysplasia is treated with periacetabular osteotomy, which reorients the acetabulum to improve coverage and delay arthritis.",
      outcomes:
        "Pavlik harness treatment has success rates above 90 percent when initiated within the first six weeks. Periacetabular osteotomy delivers 20-year joint preservation rates of around 60 percent. Untreated dysplasia progresses to arthritis by the third to fifth decade in the majority.",
    },
  },
  {
    slug: "avascular-necrosis-hip",
    name: "Avascular Necrosis of the Femoral Head",
    regionSlug: "hip",
    category: "Degenerative",
    summary:
      "Ischaemic death of subchondral bone in the femoral head leading to collapse, secondary arthritis, and a disproportionate burden in young adults.",
    sections: {
      overview:
        "Osteonecrosis of the femoral head results from disruption of the tenuous blood supply to the subchondral bone, leading to osteocyte death, structural weakening, and eventual subchondral collapse. It is a disease of younger adults (mean age 35-50) and a significant cause of hip replacement in this group.",
      epidemiology:
        "An estimated 10,000 to 20,000 new cases are diagnosed annually in the United States. Risk factors include corticosteroid use, excess alcohol, trauma, sickle cell disease, HIV treatment, Gaucher disease, decompression sickness, and autoimmune disease. Bilateral involvement occurs in up to 80 percent.",
      symptoms:
        "Insidious groin pain worsening with weight bearing is typical. Pain at rest and mechanical symptoms suggest subchondral collapse. Examination shows restricted and painful hip motion, particularly in internal rotation.",
      imaging:
        "Plain radiographs are often normal early; later features include subchondral sclerosis, the pathognomonic crescent sign of subchondral fracture, and eventual femoral head collapse. MRI is the gold standard for early detection, demonstrating the characteristic serpiginous low-signal band and bone marrow oedema.",
      classification:
        "Ficat and Arlet stages 0-IV remain widely used. The ARCO and Steinberg systems add quantitative lesion size, which is the strongest predictor of collapse. Lesions over 30 percent of the femoral head almost invariably progress.",
      management:
        "Early, small, precollapse lesions may be treated with core decompression, with or without biological augmentation. Bisphosphonates and extracorporeal shockwave have adjunctive roles in some series. Once collapse has occurred, total hip arthroplasty is the definitive treatment; younger patients increasingly receive modern ceramic-on-ceramic or ceramic-on-polyethylene bearings.",
      outcomes:
        "Core decompression succeeds in delaying arthroplasty in approximately two-thirds of early-stage lesions. Total hip arthroplasty gives pain relief and functional restoration comparable to primary OA, though revision rates are slightly higher owing to younger patient age.",
    },
  },
  // ---------------- SHOULDER ----------------
  {
    slug: "rotator-cuff-tear",
    name: "Rotator Cuff Tear",
    regionSlug: "shoulder",
    category: "Degenerative",
    summary:
      "Partial or full-thickness disruption of one or more rotator cuff tendons, most commonly supraspinatus, driven by age-related degeneration and mechanical factors.",
    sections: {
      overview:
        "The rotator cuff (supraspinatus, infraspinatus, teres minor, subscapularis) centres the humeral head in the glenoid and powers rotation. Tears are common and may be degenerative, traumatic, or, most frequently, acute-on-chronic. The natural history is progressive, with many asymptomatic tears becoming symptomatic over time and increasing in size.",
      epidemiology:
        "Prevalence rises sharply with age: around 10 percent in those under 60 and more than 50 percent in those over 80. Most are asymptomatic. Dominant arm use, overhead occupation, smoking, and diabetes increase risk.",
      symptoms:
        "Lateral shoulder pain, nocturnal pain particularly when lying on the affected side, and painful arc on abduction are typical. Weakness on external rotation (infraspinatus) or in empty-can testing (supraspinatus) indicates full-thickness tear. Lift-off and belly-press tests assess subscapularis.",
      imaging:
        "Plain radiographs show secondary signs (proximal humeral migration, greater tuberosity cystic change, acromial spurs). Ultrasound and MRI are both accurate for full-thickness tears; MRI offers superior assessment of muscle quality (Goutallier fatty infiltration) and tear geometry, which drive reparability.",
      classification:
        "Partial-thickness tears are classified by Ellman as grade 1-3 depending on depth. Full-thickness tears are described by size (Cofield/DeOrio) and pattern (crescentic, U-shaped, L-shaped, massive). Goutallier stages 0-4 quantify fatty infiltration and predict reparability.",
      management:
        "Non-operative management (analgesia, physiotherapy, targeted injections) is effective for many degenerative tears and is first line in older, lower-demand patients. Arthroscopic repair is offered to active patients with reparable tears and those with traumatic full-thickness tears in whom early repair improves healing. Irreparable massive tears with pseudoparalysis and arthritis are treated with reverse total shoulder arthroplasty.",
      outcomes:
        "Repair healing rates depend heavily on tear size, age, and muscle quality, ranging from 90 percent in small tears to 40 percent in massive tears. Functional outcomes often exceed radiographic healing. Reverse shoulder arthroplasty reliably restores forward elevation in cuff tear arthropathy.",
    },
  },
  {
    slug: "adhesive-capsulitis",
    name: "Adhesive Capsulitis (Frozen Shoulder)",
    regionSlug: "shoulder",
    category: "Inflammatory",
    summary:
      "A self-limiting but prolonged inflammatory and fibrotic contracture of the glenohumeral capsule producing marked pain and loss of motion.",
    sections: {
      overview:
        "Adhesive capsulitis is characterised by inflammation and subsequent fibrotic contracture of the glenohumeral joint capsule, most notably the rotator interval and coracohumeral ligament. Primary (idiopathic) and secondary (post-traumatic, post-surgical, associated with diabetes or thyroid disease) forms are recognised. The hallmark is global loss of both active and passive range of motion.",
      epidemiology:
        "Lifetime prevalence is 2 to 5 percent in the general population and up to 20 percent in patients with diabetes. It most commonly affects women aged 40 to 60 and has a predilection for the non-dominant shoulder. Bilateral involvement, sequentially rather than simultaneously, is seen in up to 20 percent.",
      symptoms:
        "The classic three-phase course comprises painful (freezing), stiff (frozen), and thawing phases, each lasting several months. Patients describe progressive loss of external rotation, difficulty reaching behind the back, and severe night pain. Passive motion is equally restricted as active motion, distinguishing it from rotator cuff disease.",
      imaging:
        "Radiographs are typically normal and are obtained to exclude arthritis and calcific tendonitis. MRI may show thickening of the coracohumeral ligament, inferior capsule, and rotator interval, with contrast arthrography demonstrating a reduced joint volume (<10 mL).",
      classification:
        "Neviaser described arthroscopic stages I-IV based on synovial inflammation and capsular contracture. The clinical freezing-frozen-thawing schema remains most practically useful.",
      management:
        "Most patients improve with education, analgesia, and a targeted physiotherapy programme emphasising stretching within tolerance. Intra-articular corticosteroid and hydrodilatation give meaningful short-term benefit. Refractory cases (typically more than 6-12 months) may be offered manipulation under anaesthesia or arthroscopic capsular release.",
      outcomes:
        "The condition is usually self-limiting over 12 to 30 months; however, up to 40 percent of patients have some residual motion deficit at long-term follow-up, particularly those with diabetes. Surgical release gives rapid motion gains with good durability.",
    },
  },
  {
    slug: "glenohumeral-oa",
    name: "Glenohumeral Osteoarthritis",
    regionSlug: "shoulder",
    category: "Degenerative",
    summary:
      "Degenerative cartilage loss in the glenohumeral joint causing progressive pain and stiffness, often with characteristic posterior glenoid erosion.",
    sections: {
      overview:
        "Glenohumeral osteoarthritis may be primary or secondary to trauma, instability, chronic rotator cuff disease, avascular necrosis, or inflammatory arthropathy. Primary OA characteristically produces posterior glenoid wear, posterior humeral subluxation, and inferior humeral osteophytes. Advanced disease causes substantial functional limitation.",
      epidemiology:
        "Radiographic glenohumeral OA is present in 4 to 30 percent of adults over 60, and symptomatic disease is less common than in the hip or knee. The prevalence of shoulder arthroplasty has grown rapidly in recent decades, driven by expanded indications for anatomic and reverse designs.",
      symptoms:
        "Patients describe deep posterior shoulder pain, night pain, loss of external rotation, and progressive functional decline. Crepitus and grinding on motion are common. Stiffness may precede or accompany pain and may mimic adhesive capsulitis in early disease.",
      imaging:
        "True AP, axillary lateral, and Y-views are the radiographic standard. CT defines glenoid morphology and is essential for preoperative planning; MRI is helpful to assess rotator cuff integrity, which determines the type of arthroplasty.",
      classification:
        "Walch classification of glenoid morphology (A1, A2, B1, B2, B3, C, D) remains the reference for preoperative planning. Samilson-Prieto grades capsulorrhaphy arthropathy.",
      management:
        "Non-operative management includes activity modification, physiotherapy, NSAIDs, and intra-articular injections. Arthroscopic debridement has limited role. Anatomic total shoulder arthroplasty is indicated for advanced disease with an intact rotator cuff; reverse total shoulder arthroplasty is the implant of choice with cuff deficiency, significant glenoid erosion, or in the older population.",
      outcomes:
        "Anatomic total shoulder arthroplasty achieves 90 percent implant survival at 10 years with good pain relief and motion. Reverse designs have transformed outcomes in cuff-deficient shoulders. Glenoid component loosening is the principal long-term failure mode of anatomic designs.",
    },
  },
  {
    slug: "anterior-shoulder-instability",
    name: "Anterior Shoulder Instability",
    regionSlug: "shoulder",
    category: "Traumatic",
    summary:
      "Recurrent or symptomatic anterior translation of the humeral head from the glenoid, typically following a traumatic dislocation in a young patient.",
    sections: {
      overview:
        "Anterior shoulder instability is the most common form of glenohumeral instability, usually the sequel of a traumatic anterior dislocation in which the humeral head disrupts the anteroinferior labrum and capsuloligamentous complex (Bankart lesion). Subsequent episodes may occur with decreasing trauma.",
      epidemiology:
        "First-time anterior dislocation incidence is approximately 23 per 100,000 person-years, with a strong young male predominance. Recurrence risk after non-operative management ranges from 60 to 90 percent in patients under 20 engaged in contact sport, dropping to below 20 percent in those over 40.",
      symptoms:
        "After initial dislocation, patients report apprehension and recurrent subluxations or dislocations with abduction and external rotation. Examination employs apprehension, relocation, and surprise tests. Neurovascular examination, particularly axillary nerve, is essential at first presentation.",
      imaging:
        "Plain radiographs (AP, scapular Y, axillary) confirm reduction and assess bony defects. MRI and MR arthrography define labral and capsular injury. CT with 3D reconstruction quantifies glenoid bone loss and Hill-Sachs lesions, essential for surgical planning.",
      classification:
        "Described by recurrence (first-time vs recurrent), volition (traumatic vs atraumatic), and direction (anterior, posterior, multidirectional). The Instability Severity Index Score (ISIS) and glenoid track concept guide choice between soft-tissue (Bankart) and bony (Latarjet) procedures.",
      management:
        "Initial dislocation is reduced with appropriate analgesia and immobilised briefly; early arthroscopic stabilisation is considered in young athletes at high recurrence risk. Arthroscopic Bankart repair is the mainstay for soft-tissue instability; significant glenoid bone loss (>15-20 percent) is an indication for Latarjet or free bone graft transfer.",
      outcomes:
        "Arthroscopic Bankart repair gives recurrence rates of 5 to 15 percent in selected patients. Latarjet provides durable stability even with bone loss, with recurrence rates around 2 to 5 percent in most series. Early intervention in at-risk young athletes reduces reinjury and chondral damage.",
    },
  },
  // ---------------- SPINE ----------------
  {
    slug: "lumbar-disc-herniation",
    name: "Lumbar Disc Herniation",
    regionSlug: "spine",
    category: "Degenerative",
    summary:
      "Displacement of nucleus pulposus material beyond the disc space, commonly causing radiculopathy through compression of a nerve root.",
    sections: {
      overview:
        "Lumbar disc herniation occurs when nucleus pulposus extrudes through a defect in the annulus fibrosus, most often posterolaterally into the lateral recess where it compresses the traversing nerve root. L4/5 and L5/S1 account for the majority of symptomatic herniations. Natural history is favourable, with most symptomatic herniations resorbing partially and producing symptom relief over weeks to months.",
      epidemiology:
        "Lifetime prevalence of sciatica is around 13 to 40 percent; symptomatic disc herniation accounts for a minority of these. Peak presentation is in the fourth and fifth decades. Heavy lifting, prolonged driving, smoking, and genetic factors are recognised risk factors.",
      symptoms:
        "Dermatomal leg pain typically exceeding the back pain component, often with positive straight leg raise (Lasègue) or crossed straight leg raise. Neurological examination may reveal a focal motor or sensory deficit corresponding to the affected root. Cauda equina syndrome, with saddle anaesthesia, bladder dysfunction, and bilateral leg symptoms, is a surgical emergency.",
      imaging:
        "MRI is the modality of choice, defining the level, laterality, morphology, and nerve root compression. Incidental disc pathology is common and imaging must be interpreted in the clinical context. CT myelography is reserved for patients unable to have MRI.",
      classification:
        "The combined CTF/ASSR/NASS classification describes bulge, protrusion, extrusion, and sequestration. Spinal stenosis grading, migration level, and Modic endplate changes add biomechanical context.",
      management:
        "Initial management is conservative with simple analgesia, NSAIDs, short-term activity modification, and structured physiotherapy. Epidural steroid injections provide short-term benefit. Microdiscectomy is offered for persistent radiculopathy beyond 6-12 weeks, progressive neurological deficit, or cauda equina. The SPORT trial showed early advantage to surgery, converging with non-operative care at two years in many patients.",
      outcomes:
        "Around 80 to 90 percent of patients improve with conservative care within 6 weeks. Microdiscectomy offers faster symptom relief with reherniation rates of 5 to 15 percent. Long-term outcomes are broadly similar between groups except for speed of recovery and return to work.",
    },
  },
  {
    slug: "cervical-spondylotic-myelopathy",
    name: "Cervical Spondylotic Myelopathy",
    regionSlug: "spine",
    category: "Degenerative",
    summary:
      "Degenerative narrowing of the cervical canal producing chronic spinal cord compression and progressive neurological dysfunction.",
    sections: {
      overview:
        "Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction in adults over 55. Degenerative changes including disc collapse, uncovertebral and facet hypertrophy, ligamentum flavum infolding, and posterior longitudinal ligament ossification compromise the cervical canal, causing direct mechanical injury and secondary vascular ischaemia to the cord.",
      epidemiology:
        "Prevalence rises with age; radiographic stenosis is present in a substantial minority of asymptomatic older adults, but symptomatic CSM is less common. It is the leading non-traumatic cause of spinal cord injury worldwide.",
      symptoms:
        "Patients typically present with insidious hand clumsiness, gait imbalance, and upper motor neuron signs (hyperreflexia, Hoffmann, Babinski, clonus). Pain is variable and often absent. Lhermitte phenomenon, sphincter disturbance, and falls occur in advanced disease. The modified Japanese Orthopaedic Association (mJOA) score quantifies severity.",
      imaging:
        "MRI is the standard for assessing cord compression, signal change, and canal dimensions. T2 hyperintensity within the cord signals established myelomalacia and is prognostic. Dynamic flexion-extension radiographs or MRI may reveal instability contributing to compression.",
      classification:
        "The mJOA categorises mild (15-17), moderate (12-14), and severe (<12) disease. Nurick and Ranawat grading are alternatives. Anatomical patterns (diffuse, focal, OPLL-driven) guide surgical approach.",
      management:
        "Mild cases are monitored closely with lifestyle and fall prevention advice. Moderate or severe CSM, or progressive mild disease, is treated surgically. Anterior (discectomy and fusion, corpectomy) and posterior (laminoplasty, laminectomy with fusion) approaches are selected on the basis of location of compression, sagittal alignment, and number of levels.",
      outcomes:
        "Surgical decompression reliably halts progression and produces partial recovery of function in most patients. The AOSpine CSM International studies show sustained improvement in mJOA and quality of life at 2 years. Duration and severity of symptoms prior to surgery are the strongest predictors of recovery.",
    },
  },
  {
    slug: "lumbar-spinal-stenosis",
    name: "Lumbar Spinal Stenosis",
    regionSlug: "spine",
    category: "Degenerative",
    summary:
      "Narrowing of the central canal, lateral recess, or foramen of the lumbar spine producing neurogenic claudication in older adults.",
    sections: {
      overview:
        "Degenerative lumbar stenosis is the most common reason for spine surgery in patients over 65. Disc-space loss, facet and ligamentum flavum hypertrophy, and osteophyte formation narrow the space available for neural elements, compromising vascular supply and mechanical function of the cauda equina.",
      epidemiology:
        "Radiographic stenosis is present in up to 20 percent of asymptomatic adults over 60. Symptomatic stenosis accounts for several hundred thousand procedures per year worldwide and is expected to grow with an ageing population.",
      symptoms:
        "Neurogenic claudication - bilateral buttock and leg pain, heaviness or weakness on walking or standing, relieved by forward flexion or sitting - is the classic syndrome. Patients describe a 'shopping trolley sign' of improved symptoms with flexion. Unlike vascular claudication, symptoms are provoked by standing even without walking and relieved by posture rather than rest.",
      imaging:
        "MRI is the modality of choice, showing central canal narrowing, effacement of CSF, lateral recess and foraminal stenosis, and facet hypertrophy. Upright or dynamic imaging may expose occult instability. Weight-bearing films assess sagittal balance and degenerative spondylolisthesis.",
      classification:
        "Anatomical (central, lateral recess, foraminal) and severity grading (Schizas, qualitative) are commonly used. Presence of degenerative spondylolisthesis is an important prognostic and surgical variable.",
      management:
        "Conservative care comprises physiotherapy, activity modification, and simple analgesia. Epidural steroid injections give variable short-term benefit. Decompressive surgery (laminectomy, laminotomy, minimally invasive approaches) is offered for persistent or disabling symptoms. Fusion is added selectively in the presence of instability or significant deformity; the SLIP and SPORT trials inform this decision.",
      outcomes:
        "Decompression gives durable symptom relief in approximately 70 percent of appropriately selected patients. Outcomes of conservative care are modest but acceptable in many. Shared decision making, accounting for comorbidity and functional goals, is central.",
    },
  },
  {
    slug: "adolescent-idiopathic-scoliosis",
    name: "Adolescent Idiopathic Scoliosis",
    regionSlug: "spine",
    category: "Congenital",
    summary:
      "A three-dimensional deformity of the growing spine of unknown cause, characterised by lateral curvature and vertebral rotation during adolescence.",
    sections: {
      overview:
        "Adolescent idiopathic scoliosis (AIS) is defined as a lateral spinal curvature of 10 degrees or more in an otherwise healthy adolescent. It is three-dimensional, with coupled rotation producing rib prominence. Cause is unknown but genetic, neurohormonal, biomechanical, and growth-related factors are implicated.",
      epidemiology:
        "Prevalence is around 2 to 3 percent of adolescents, with girls disproportionately affected by progressive curves requiring treatment (female:male ratio 7:1 for curves >30 degrees). Progression risk is greatest during the pubertal growth spurt.",
      symptoms:
        "Most adolescents are asymptomatic. Deformity is detected on school or clinical screening (Adam's forward bend test, rib prominence measured with a scoliometer). Pain is unusual and, when present, prompts evaluation for secondary causes. Neurological examination is always performed to screen for underlying pathology.",
      imaging:
        "Standing PA and lateral full-spine radiographs are the standard, with Cobb angle measurement and Risser staging of skeletal maturity. MRI is reserved for atypical presentations (left thoracic curves, rapid progression, pain, neurological signs, very young patients).",
      classification:
        "Lenke classification (types 1-6 with lumbar modifier and sagittal modifier) guides operative planning. King-Moe is historical. Non-operative decision making uses curve magnitude, skeletal maturity, and rate of progression.",
      management:
        "Observation is adequate for curves below 25 degrees in growing patients. Bracing (TLSO, night-time braces) is indicated for progressive curves of 25-45 degrees in skeletally immature patients; the BrAIST trial demonstrated efficacy proportional to hours worn. Surgical correction (posterior instrumented fusion) is considered for curves exceeding 45-50 degrees with ongoing growth or 50 degrees in mature patients.",
      outcomes:
        "Modern pedicle screw constructs achieve excellent three-dimensional correction with sustained improvement on SRS-22 quality-of-life measures. Progression after skeletal maturity is slow in most curves below 50 degrees; larger curves tend to progress 0.5 to 1 degree per year through adulthood.",
    },
  },
  // ---------------- FOOT & ANKLE ----------------
  {
    slug: "plantar-fasciitis",
    name: "Plantar Fasciitis",
    regionSlug: "foot-ankle",
    category: "Inflammatory",
    summary:
      "Overuse-related degenerative and inflammatory change at the plantar fascia origin on the medial calcaneal tubercle, producing heel pain.",
    sections: {
      overview:
        "Plantar fasciitis - more accurately plantar fasciopathy - is a chronic degenerative process at the origin of the plantar fascia on the medial tubercle of the calcaneus. Repetitive traction loading, combined with reduced ankle dorsiflexion and high loading rate during gait, is thought to initiate microtears and failed repair.",
      epidemiology:
        "It is the most common cause of plantar heel pain, affecting an estimated 10 percent of the population over a lifetime. Peak incidence is between 40 and 60 years. Runners, obese individuals, and those with occupations requiring prolonged standing are at higher risk.",
      symptoms:
        "Patients describe sharp medial heel pain worst with the first steps in the morning or after rest, easing with ambulation and worsening again by the end of the day. Tenderness is localised to the medial calcaneal tubercle. Symptoms may persist for months to years.",
      imaging:
        "Diagnosis is clinical. Ultrasound demonstrates plantar fascia thickening (>4 mm) and hypoechogenicity. MRI shows similar features and is useful when the diagnosis is uncertain or for refractory cases. Plain radiographs may show incidental heel spurs, which are of limited prognostic significance.",
      classification:
        "No formal grading system dominates practice; symptom duration (<6 months, >6 months) and response to treatment guide management decisions.",
      management:
        "First-line treatment is activity modification, calf and plantar fascia stretching, supportive footwear, and heel cushioning. Night splints and custom orthoses help selected patients. Corticosteroid injection gives short-term relief but carries a small risk of fascial rupture. Shockwave therapy has good evidence for refractory cases. Surgical release is reserved for the minority with symptoms persisting beyond 12 months.",
      outcomes:
        "Approximately 80 to 90 percent of patients resolve with conservative treatment within one year. Shockwave and platelet-rich plasma can improve outcomes in refractory cases. Surgical release is effective but has a small complication profile and is a last resort.",
    },
  },
  {
    slug: "hallux-valgus",
    name: "Hallux Valgus",
    regionSlug: "foot-ankle",
    category: "Degenerative",
    summary:
      "Progressive lateral deviation of the great toe with medial eminence prominence, often accompanied by pain and functional footwear difficulty.",
    sections: {
      overview:
        "Hallux valgus is a complex three-dimensional deformity involving lateral deviation of the hallux, medial deviation of the first metatarsal, pronation of the hallux, and subluxation of the first MTPJ. It reflects failure of the medial soft-tissue restraints under biomechanical load.",
      epidemiology:
        "Prevalence varies widely but may exceed 20 percent of adults and 35 percent of those over 65, with a strong female predominance. Family history, hypermobility, pes planus, and restrictive footwear contribute.",
      symptoms:
        "Patients report pain at the medial eminence exacerbated by shoes, transfer metatarsalgia, and functional discomfort. Examination evaluates the passive correctability, hallux MTPJ range, first tarsometatarsal mobility, and associated lesser toe deformities.",
      imaging:
        "Weight-bearing AP, lateral, and sesamoid views allow measurement of hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA), and sesamoid position. Lateral view assesses first ray elevation and arthrosis.",
      classification:
        "Mild (HVA <20°, IMA <11°), moderate (HVA 20-40°, IMA 11-16°), and severe (HVA >40°, IMA >16°) categories guide procedural choice. Concomitant arthritis, lesser-toe involvement, and hypermobility further refine planning.",
      management:
        "Non-operative treatment is shoe-wear modification, bunion pads, toe spacers, and analgesia; no conservative measure reliably reverses the deformity. Surgical correction is symptom-driven and tailored to deformity severity, ranging from distal metatarsal osteotomies (chevron) for mild-moderate deformity through proximal osteotomies, modified Lapidus, and double osteotomies for severe or unstable cases.",
      outcomes:
        "Modern techniques deliver patient satisfaction rates of 85 to 90 percent, with recurrence rates around 10 percent, higher when surgery is undertaken for cosmetic indications or when the biomechanical cause is not adequately addressed.",
    },
  },
  {
    slug: "achilles-rupture",
    name: "Achilles Tendon Rupture",
    regionSlug: "foot-ankle",
    category: "Traumatic",
    summary:
      "Complete disruption of the Achilles tendon, typically in middle-aged recreational athletes, causing sudden calf pain and loss of plantarflexion power.",
    sections: {
      overview:
        "Achilles tendon ruptures most commonly occur 2 to 6 cm proximal to the calcaneal insertion in a relatively avascular zone. Pre-existing tendinopathy, age-related collagen degeneration, and sudden eccentric loading during sport combine to produce rupture. The 'weekend warrior' demographic is classical.",
      epidemiology:
        "Incidence is around 20 to 40 per 100,000 person-years and is rising in high-income countries. Peak age is 30 to 50, with male predominance. Fluoroquinolone use and corticosteroid exposure are established risk factors.",
      symptoms:
        "Patients typically describe a sudden blow or pop at the back of the ankle and difficulty walking. Examination reveals a palpable gap, weakness of plantarflexion, and a positive Thompson (Simmonds) test with calf squeeze failing to produce plantarflexion. Residual plantarflexion by tibialis posterior and FHL may deceive the unwary.",
      imaging:
        "Diagnosis is clinical. Ultrasound confirms the gap and is useful to differentiate complete from partial ruptures and to assess dynamic opposition in equinus. MRI is reserved for chronic or complex cases and preoperative planning.",
      classification:
        "Kuwada classification (I-IV) describes partial ruptures and complete tears with increasing defect size, guiding reconstructive strategy in chronic rupture.",
      management:
        "Both operative repair and functional non-operative treatment with early weight bearing and equinus casting or bracing give comparable re-rupture rates (5 to 10 percent) in modern trials. Functional rehabilitation, rather than the treatment modality, appears to be the critical determinant. Surgical repair - open or minimally invasive - offers slightly faster return to high-level sport and lower re-rupture in selected cohorts.",
      outcomes:
        "Most patients return to pre-injury activities within 6 to 12 months. Sural nerve injury and wound complications are surgical risks; re-rupture is the principal concern with both strategies. Long-term calf atrophy and slight plantarflexion weakness often persist.",
    },
  },
  // ---------------- HAND & WRIST ----------------
  {
    slug: "carpal-tunnel-syndrome",
    name: "Carpal Tunnel Syndrome",
    regionSlug: "hand-wrist",
    category: "Inflammatory",
    summary:
      "Compression of the median nerve at the wrist beneath the transverse carpal ligament, producing the most common upper-limb entrapment neuropathy.",
    sections: {
      overview:
        "Carpal tunnel syndrome results from increased pressure within the carpal tunnel, causing median nerve ischaemia and demyelination. Idiopathic disease reflects a combination of anatomical, occupational, and systemic factors including synovial thickening, pregnancy, diabetes, hypothyroidism, and rheumatoid disease.",
      epidemiology:
        "Lifetime prevalence is estimated at 3 to 5 percent of the adult population, with strong female and middle-age predominance. Bilateral involvement is common, often with the dominant hand more severe.",
      symptoms:
        "Nocturnal pain, paraesthesia, and numbness in the median nerve distribution (thumb, index, middle, radial half of ring finger) are hallmarks, often relieved by shaking the hand (flick sign). Advanced disease produces thenar atrophy and weakness of thumb abduction. Provocative tests include Phalen, Durkan's carpal compression, and Tinel.",
      imaging:
        "Diagnosis is primarily clinical with electrodiagnostic confirmation (NCS/EMG) grading severity. Ultrasound is increasingly used as a rapid, radiation-free alternative, assessing median nerve cross-sectional area at the tunnel inlet.",
      classification:
        "Severity is classified as mild, moderate, severe, or very severe on the basis of sensory and motor nerve conduction velocity and latency parameters. The Boston Carpal Tunnel Questionnaire quantifies symptoms and function.",
      management:
        "Mild to moderate cases respond to night splinting and activity modification; corticosteroid injection provides short to medium-term relief in many patients. Carpal tunnel release (open or endoscopic) is indicated for moderate to severe disease, refractory symptoms, or thenar atrophy, with decompression of the transverse carpal ligament as the definitive treatment.",
      outcomes:
        "Surgical release provides durable symptom relief in 90 percent of patients, with rapid improvement in paraesthesia. Thenar strength and two-point discrimination recover more slowly, and long-standing severe disease may leave residual deficit.",
    },
  },
  {
    slug: "de-quervain-tenosynovitis",
    name: "De Quervain's Tenosynovitis",
    regionSlug: "hand-wrist",
    category: "Inflammatory",
    summary:
      "Painful tenosynovitis of the first dorsal extensor compartment at the wrist, involving APL and EPB tendons.",
    sections: {
      overview:
        "De Quervain's tenosynovitis is a stenosing tenosynovitis of the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) tendons in the first dorsal compartment of the wrist. Thickening of the extensor retinaculum narrows the fibro-osseous tunnel; a separate compartment for EPB is a common anatomical variant contributing to refractory cases.",
      epidemiology:
        "It is most common in women aged 30 to 50, particularly during pregnancy and the postpartum period, and in occupations involving repetitive thumb and wrist use. It is sometimes called 'gamer's thumb' or 'baby wrist'.",
      symptoms:
        "Pain and tenderness over the radial styloid, worse with thumb use and ulnar wrist deviation, are characteristic. Finkelstein and Eichhoff tests reproduce symptoms. Palpable thickening of the first dorsal compartment may be felt.",
      imaging:
        "Diagnosis is clinical. Ultrasound shows tendon and retinacular thickening, peritendinous fluid, and any subdivided compartments. Plain radiographs exclude thumb CMC arthritis or scaphoid pathology.",
      classification:
        "No widely used formal classification. Description typically notes presence of a separate EPB subcompartment, which predicts response to injection.",
      management:
        "Splinting of the thumb and wrist (thumb spica) with NSAIDs relieves mild cases. Corticosteroid injection into the first compartment, with or without ultrasound guidance, achieves high success rates (>80 percent). Surgical release of the first compartment is indicated for refractory cases; it is essential to identify and release any EPB subcompartment.",
      outcomes:
        "Injection therapy is curative in most cases; surgical release has high success with low complication rates (superficial radial nerve injury and instability of the APL/EPB tendons are recognised). Recurrence is infrequent.",
    },
  },
  // ---------------- ELBOW ----------------
  {
    slug: "lateral-epicondylitis",
    name: "Lateral Epicondylitis (Tennis Elbow)",
    regionSlug: "elbow",
    category: "Degenerative",
    summary:
      "Degenerative enthesopathy of the common extensor origin at the lateral humeral epicondyle, a frequent cause of lateral elbow pain.",
    sections: {
      overview:
        "Lateral epicondylitis is a degenerative tendinopathy of the common extensor origin, particularly the extensor carpi radialis brevis (ECRB). Despite the suffix, histology shows angiofibroblastic hyperplasia without inflammatory cells, more accurately termed a tendinosis. Repetitive wrist extension and forearm supination are implicated, in sport and in occupational settings.",
      epidemiology:
        "Annual incidence is around 1 to 3 percent of the general population, peaking between 40 and 60 years with no sex predilection. Only a minority of cases arise from tennis, despite the eponym.",
      symptoms:
        "Patients describe lateral elbow pain radiating into the forearm, worse with gripping, lifting, and resisted wrist extension. Pain on resisted middle finger extension (Maudsley test), resisted wrist extension with elbow extended, and tenderness just distal to the lateral epicondyle are diagnostic.",
      imaging:
        "Diagnosis is clinical. Ultrasound and MRI can confirm tendon changes and exclude differentials (radial tunnel syndrome, posterolateral rotatory instability, synovial plica, osteoarthritis). Imaging is reserved for atypical or refractory cases.",
      classification:
        "Nirschl and Pettrone phases I-IV describe histopathologic and clinical progression; Coel/Regan ultrasound grading is used for imaging severity.",
      management:
        "Most cases are self-limiting over 12 to 18 months. First-line treatment is activity modification, eccentric strengthening, counterforce bracing, and simple analgesia. Corticosteroid injection gives short-term relief but may worsen long-term outcomes and should be used with caution. Shockwave therapy and platelet-rich plasma have modest evidence for refractory cases. Surgical debridement or release of the ECRB origin is considered after 6-12 months of persistent symptoms.",
      outcomes:
        "Around 80 to 90 percent of patients recover with non-operative treatment within one to two years. Surgery has good outcomes but carries small risks of instability and residual pain.",
    },
  },
  {
    slug: "olecranon-bursitis",
    name: "Olecranon Bursitis",
    regionSlug: "elbow",
    category: "Inflammatory",
    summary:
      "Inflammation of the olecranon bursa at the posterior elbow, either inflammatory or septic, producing characteristic swelling over the olecranon.",
    sections: {
      overview:
        "Olecranon bursitis is inflammation of the subcutaneous bursa overlying the olecranon process. Traumatic, inflammatory (gout, rheumatoid), and septic subtypes are distinguished. Because the bursa lies superficially, it is readily traumatised and infected, most commonly by Staphylococcus aureus.",
      epidemiology:
        "Males predominate, particularly those in occupations involving elbow leaning or minor trauma ('student's elbow', 'miner's elbow'). Precise incidence is not well characterised, but it is a common presentation to emergency departments and primary care.",
      symptoms:
        "A well-defined swelling over the olecranon, typically non-tender in chronic non-septic cases and warm, red, and exquisitely tender in septic bursitis. Elbow range of motion is preserved, in contrast to septic arthritis. Systemic signs suggest infection.",
      imaging:
        "Diagnosis is clinical. Ultrasound confirms fluid collection and can be used to guide aspiration. Plain radiographs exclude underlying bony abnormality. Aspiration fluid is sent for Gram stain, culture, cell count, and crystal analysis.",
      classification:
        "Septic vs non-septic (inflammatory, traumatic, idiopathic) is the principal clinical distinction and drives management.",
      management:
        "Aseptic bursitis is managed with activity modification, padding, NSAIDs, and aspiration with or without steroid injection in persistent cases. Recurrent cases may require bursectomy. Septic bursitis requires aspiration, antibiotics, and occasionally surgical drainage; rapid clinical improvement with appropriate antibiotics is typical for early cases.",
      outcomes:
        "Most aseptic cases resolve with conservative care. Recurrent and chronic aseptic cases have modest success with bursectomy, with wound complications being the main concern. Septic bursitis carries an excellent prognosis with timely treatment.",
    },
  },

  // ---------------- ADDITIONAL ENTRIES ----------------
  {
    slug: "patellofemoral-pain-syndrome",
    name: "Patellofemoral Pain Syndrome",
    regionSlug: "knee",
    category: "Degenerative",
    summary:
      "A common cause of anterior knee pain, particularly in young active patients, arising from altered patellofemoral joint loading without a single discrete structural lesion.",
    sections: {
      overview:
        "Patellofemoral pain syndrome (PFPS) describes anterior or retropatellar knee pain aggravated by activities that load the patellofemoral joint, such as stair climbing, squatting, and prolonged sitting. The aetiology is multifactorial and includes malalignment, dynamic valgus from proximal weakness, vastus medialis obliquus insufficiency, soft-tissue tightness, and overuse. No single pathoanatomic lesion is consistently identified, and PFPS is best conceptualised as a syndrome of altered load distribution.",
      epidemiology:
        "PFPS is one of the most common musculoskeletal presentations in adolescents and young adults, with prevalence estimates of 15 to 25 percent in athletic and military populations. Females are affected roughly twice as often as males, likely reflecting differences in pelvic width, dynamic knee valgus, and hip abductor strength.",
      symptoms:
        "Patients describe diffuse anterior or peripatellar pain, the classic theatre sign of pain after prolonged sitting, and pain descending stairs. Examination reveals pain on patellar compression, occasional crepitus, and dynamic valgus during single-leg squat. Effusion and mechanical symptoms are characteristically absent.",
      imaging:
        "PFPS is a clinical diagnosis. Imaging is used to exclude alternative pathology when symptoms persist. Plain radiographs including a skyline view assess patellar tilt, trochlear morphology, and osteoarthritis. MRI is reserved for refractory cases and can demonstrate cartilage lesions, bone marrow oedema, or excluded meniscal pathology.",
      classification:
        "No universally accepted classification exists. Clinically useful descriptors include overuse-related, malalignment-related, and instability-associated subtypes, while the Dye pain envelope concept frames PFPS as loss of tissue homeostasis under load.",
      management:
        "First-line treatment is structured rehabilitation emphasising hip abductor, external rotator, and quadriceps strengthening, with activity modification and analgesia as adjuncts. Patellar taping, orthoses, and gait retraining have modest supportive evidence. Injections and surgery have limited roles and are reserved for refractory cases with clearly defined pathology.",
      outcomes:
        "With adherent rehabilitation, most patients improve substantially within three to six months. A subset develop chronic symptoms, and PFPS is recognised as a risk factor for later patellofemoral osteoarthritis.",
    },
  },
  {
    slug: "iliotibial-band-syndrome",
    name: "Iliotibial Band Syndrome",
    regionSlug: "knee",
    category: "Inflammatory",
    summary:
      "An overuse syndrome of the lateral knee in runners and cyclists, producing pain as the iliotibial band tracks over the lateral femoral epicondyle.",
    sections: {
      overview:
        "Iliotibial band syndrome (ITBS) is the most common cause of lateral knee pain in distance runners. Pain is attributed to compression and inflammation of a richly innervated fat pad deep to the distal iliotibial band rather than true friction over the epicondyle. Training errors, downhill running, weak hip abductors, and anatomical factors such as genu varum contribute.",
      epidemiology:
        "ITBS accounts for up to 12 percent of running-related injuries and is also common in cyclists. Peak incidence is between 20 and 40 years with no strong sex predilection; female runners with increased hip adduction during stance are at higher risk.",
      symptoms:
        "Sharp or burning lateral knee pain develops at a reproducible distance into activity and progressively shortens as the condition worsens. Pain is maximal at around 30 degrees of flexion and is aggravated by downhill running. Tenderness over the lateral femoral epicondyle and a positive Noble compression test are characteristic.",
      imaging:
        "The diagnosis is clinical. MRI in refractory cases shows thickening of the distal iliotibial band with signal changes in the underlying fat pad. Ultrasound is a reasonable alternative.",
      classification:
        "No formal classification. Severity is best described by functional impact using running distance thresholds.",
      management:
        "Management is almost entirely non-operative: relative rest, training modification, eccentric hip abductor strengthening, soft-tissue work, and gait retraining to reduce contralateral pelvic drop. Corticosteroid injection is effective for persistent symptoms. Surgical release of the posterior iliotibial band or bursectomy is reserved for refractory cases.",
      outcomes:
        "More than 90 percent of runners return to sport with structured rehabilitation within eight to twelve weeks. Recurrence is common when training errors are not addressed.",
    },
  },
  {
    slug: "piriformis-syndrome",
    name: "Piriformis Syndrome",
    regionSlug: "hip",
    category: "Inflammatory",
    summary:
      "A non-discogenic cause of sciatic-type buttock and leg pain attributed to compression or irritation of the sciatic nerve by the piriformis muscle.",
    sections: {
      overview:
        "Piriformis syndrome is a controversial but clinically useful label for deep gluteal pain with radiating symptoms arising from sciatic nerve irritation in the infrapiriformis space. Anatomical variants, including the sciatic nerve passing through or splitting the piriformis, hypertrophy, and trauma are implicated. It remains a diagnosis of exclusion after discogenic and other causes of sciatica are ruled out.",
      epidemiology:
        "Piriformis syndrome is estimated to account for 6 to 8 percent of presentations of low back and buttock pain, although the true incidence is uncertain. Women are more commonly affected, with peak presentation in the fourth and fifth decades.",
      symptoms:
        "Deep buttock pain radiating down the posterior thigh, exacerbated by prolonged sitting, climbing stairs, or crossing the affected leg. Tenderness is maximal over the piriformis belly, and provocative tests such as FAIR (flexion, adduction, internal rotation), Pace, and Freiberg signs reproduce symptoms. A normal neurological examination helps distinguish from radiculopathy.",
      imaging:
        "MRI of the lumbar spine is performed to exclude discogenic sciatica. Dedicated MR neurography of the sciatic nerve at the greater sciatic foramen and ultrasound may show piriformis hypertrophy or nerve oedema. Electrodiagnostic testing helps exclude radiculopathy.",
      classification:
        "Primary (anatomical variant) and secondary (post-traumatic, inflammatory, or space-occupying) forms are recognised.",
      management:
        "First-line treatment includes activity modification, NSAIDs, and a structured physiotherapy programme targeting piriformis stretching and hip external rotator conditioning. Image-guided corticosteroid or botulinum toxin injection into the piriformis muscle can be effective. Surgical release of the piriformis and neurolysis is reserved for refractory cases.",
      outcomes:
        "Non-operative management is effective in the majority. Surgical series report good outcomes in carefully selected patients with clear imaging or electrophysiological correlation, but evidence remains limited.",
    },
  },
  {
    slug: "greater-trochanteric-pain-syndrome",
    name: "Greater Trochanteric Pain Syndrome",
    regionSlug: "hip",
    category: "Degenerative",
    summary:
      "Lateral hip pain arising from gluteal tendinopathy, tears, or trochanteric bursitis; now recognised as a tendinopathic rather than purely bursal disorder.",
    sections: {
      overview:
        "Greater trochanteric pain syndrome (GTPS) is a common cause of lateral hip pain historically attributed to trochanteric bursitis but now recognised as most often a gluteus medius and minimus tendinopathy with or without tears. Mechanical factors include hip abductor weakness, pelvic instability, and altered iliotibial band loading.",
      epidemiology:
        "Estimated prevalence is 10 to 25 percent in the general population, peaking in the fifth and sixth decades, with women affected two to four times as often as men. It is a frequent cause of persistent lateral hip pain after total hip arthroplasty.",
      symptoms:
        "Lateral hip pain worse with lying on the affected side, walking, and climbing stairs. Focal tenderness over the greater trochanter is characteristic. Single-leg stance pain at 30 seconds is a sensitive clinical test. A Trendelenburg sign suggests tendon tear.",
      imaging:
        "Plain radiographs exclude osteoarthritis and bony abnormality. Ultrasound and MRI are the principal imaging tools for tendon pathology, demonstrating tendinopathy, partial or full-thickness tears, and peritendinous fluid. MRI is preferred when surgical intervention is contemplated.",
      classification:
        "A useful clinical classification includes tendinopathy, partial-thickness tear, and full-thickness tear of the gluteus medius/minimus, with bursitis and external snapping hip as related entities.",
      management:
        "Load management, hip abductor strengthening, and weight optimisation form the foundation. Corticosteroid injection provides short-term relief. Shockwave therapy has supportive evidence for recalcitrant tendinopathy. Endoscopic or open gluteal tendon repair is indicated for symptomatic full-thickness tears in appropriate candidates.",
      outcomes:
        "Most patients improve with structured rehabilitation over six to twelve months. Tendon repair achieves good functional outcomes in carefully selected patients, with retear rates higher in chronic and fatty-atrophic tears.",
    },
  },
  {
    slug: "subacromial-impingement-syndrome",
    name: "Subacromial Impingement Syndrome",
    regionSlug: "shoulder",
    category: "Degenerative",
    summary:
      "A spectrum of shoulder pain attributed to mechanical or functional impingement of the rotator cuff beneath the coracoacromial arch, now understood as part of rotator cuff disease.",
    sections: {
      overview:
        "Subacromial impingement syndrome (SIS) describes pain and dysfunction caused by contact between the rotator cuff and the coracoacromial arch. Contemporary understanding places SIS on a continuum with rotator cuff tendinopathy, partial tear, and full-thickness tear rather than as a discrete entity. Contributing factors include acromial morphology, scapular dyskinesis, glenohumeral instability, and intrinsic tendon degeneration.",
      epidemiology:
        "Shoulder pain has an annual incidence of 15 to 25 per 1000 in primary care, and impingement-type pain represents the majority of presentations. Peak incidence is between 40 and 60 years, with overhead athletes and manual workers disproportionately affected.",
      symptoms:
        "Lateral and anterior shoulder pain with overhead activity, night pain when lying on the affected side, and a painful arc between 60 and 120 degrees of abduction. Positive Neer and Hawkins-Kennedy impingement signs are characteristic. Rotator cuff strength testing helps exclude concomitant tear.",
      imaging:
        "Plain radiographs including AP, outlet, and axillary views assess acromial morphology and exclude calcific deposits or osteoarthritis. Ultrasound and MRI are used when rotator cuff tear is suspected or when conservative treatment fails.",
      classification:
        "Neer's three stages (oedema and haemorrhage, tendinitis and fibrosis, tear and bone change) remain widely used. Bigliani acromial morphology (flat, curved, hooked) correlates with cuff disease, though causality is debated.",
      management:
        "Structured physiotherapy emphasising scapulothoracic and rotator cuff rehabilitation is first-line and supported by level-1 evidence. Subacromial corticosteroid injection gives short-term relief. Recent randomised trials (CSAW) have challenged the value of arthroscopic subacromial decompression versus sham surgery for SIS without cuff tear.",
      outcomes:
        "Most patients improve with structured rehabilitation within three to six months. Outcomes are excellent when the underlying pathology is isolated impingement without structural cuff failure.",
    },
  },
  {
    slug: "slap-tear",
    name: "SLAP Tear",
    regionSlug: "shoulder",
    category: "Traumatic",
    summary:
      "Superior labral anterior-posterior injury of the glenoid, seen in throwers and after traction or compression injuries, producing deep shoulder pain and catching.",
    sections: {
      overview:
        "SLAP tears involve the superior labrum at the origin of the long head of biceps. Mechanisms include traction, compression from a fall on an outstretched hand, and repetitive overhead loading in throwing athletes. The peel-back phenomenon and internal impingement are implicated in the throwing shoulder. Degenerative changes are increasingly recognised in older patients.",
      epidemiology:
        "SLAP tears are found in around 6 percent of shoulder arthroscopies. Peak incidence is in overhead athletes between 20 and 40 years, although they are also reported in older patients alongside rotator cuff disease.",
      symptoms:
        "Deep shoulder pain with overhead activity, loss of throwing velocity, and mechanical catching or popping. Examination manoeuvres include O'Brien's active compression test, the biceps load test, and the dynamic labral shear test; no single test is definitive and diagnostic accuracy of clinical tests is modest.",
      imaging:
        "MR arthrography is the imaging standard, with sensitivity around 85 to 90 percent. Standard MRI is less sensitive. Arthroscopy remains the definitive diagnostic tool.",
      classification:
        "The Snyder classification (types I to IV) and Maffet expansion (types V to X) describe tear morphology. Type II, an unstable biceps anchor, is the most common operative type.",
      management:
        "Non-operative treatment with rest, NSAIDs, and scapular and rotator cuff rehabilitation is first-line, particularly in non-throwers. Surgical options include arthroscopic SLAP repair in young overhead athletes and biceps tenotomy or tenodesis in older patients and recreational athletes, in whom tenodesis has generally superseded repair.",
      outcomes:
        "Return-to-sport rates after SLAP repair in throwers are variable, typically 60 to 85 percent. Biceps tenodesis provides reliable pain relief in older patients with high satisfaction.",
    },
  },
  {
    slug: "cervical-radiculopathy",
    name: "Cervical Radiculopathy",
    regionSlug: "spine",
    category: "Degenerative",
    summary:
      "Compression or inflammation of a cervical nerve root producing dermatomal arm pain with or without motor and reflex changes.",
    sections: {
      overview:
        "Cervical radiculopathy arises from nerve root compression by a disc herniation, osteophyte, or foraminal stenosis. Soft disc herniations predominate in younger patients, while cervical spondylosis with uncovertebral and facet hypertrophy dominates in older adults. C6 and C7 roots are most frequently affected.",
      epidemiology:
        "Annual incidence is around 85 per 100,000, with a peak in the fifth decade. Men are affected slightly more often than women. C7 radiculopathy accounts for roughly 60 percent of cases.",
      symptoms:
        "Unilateral arm pain in a dermatomal distribution, often worse with neck extension and rotation toward the affected side (positive Spurling test). Weakness, sensory loss, and reflex changes correspond to the involved root. Shoulder abduction relief and neck distraction tests support the diagnosis.",
      imaging:
        "MRI is the imaging standard, demonstrating the level and cause of compression. CT myelography is used when MRI is contraindicated or bony detail is essential. Electrodiagnostic studies help localise the lesion and exclude peripheral neuropathy.",
      classification:
        "Classification is by affected root (C5 to T1) and by cause (soft disc, spondylotic, foraminal stenosis). Severity is described using the quick-DASH, NDI, and VAS arm pain scores.",
      management:
        "Most patients improve with non-operative treatment including analgesia, short-course oral steroids, physiotherapy, and selective nerve root injections. Surgical options — anterior cervical discectomy and fusion, cervical disc arthroplasty, or posterior foraminotomy — are indicated for progressive neurological deficit, severe refractory pain, or myelopathic features.",
      outcomes:
        "Non-operative treatment achieves substantial improvement in 75 to 90 percent within 6 to 12 weeks. Surgical outcomes for appropriately selected patients are excellent, with 85 to 95 percent reporting significant arm pain relief.",
    },
  },
  {
    slug: "lumbar-spondylolisthesis",
    name: "Lumbar Spondylolisthesis",
    regionSlug: "spine",
    category: "Degenerative",
    summary:
      "Slippage of one vertebral body on another, typically at L4-5 (degenerative) or L5-S1 (isthmic), producing back pain, radiculopathy, or neurogenic claudication.",
    sections: {
      overview:
        "Spondylolisthesis denotes anterior (or rarely posterior) translation of one vertebra on the vertebra below. Isthmic spondylolisthesis results from a pars interarticularis defect and most commonly affects L5-S1 in adolescents and young adults, while degenerative spondylolisthesis arises from facet arthropathy and disc degeneration, most often at L4-5 in older adults.",
      epidemiology:
        "Isthmic spondylolisthesis is present in 4 to 6 percent of the population. Degenerative spondylolisthesis affects up to 10 percent of women over 60 and is five times more common in females than males.",
      symptoms:
        "Mechanical low back pain, buttock and posterior thigh pain, and features of neurogenic claudication or radiculopathy. Examination may reveal a palpable step-off, tight hamstrings, and positive neurological signs corresponding to the compressed root.",
      imaging:
        "Standing lateral radiographs are essential, with flexion-extension views assessing dynamic instability. MRI characterises neural compression and disc pathology; CT defines the pars defect and bony anatomy. Upright imaging is particularly important, as slips may reduce when supine.",
      classification:
        "Wiltse classification by aetiology (dysplastic, isthmic, degenerative, traumatic, pathologic, iatrogenic). Meyerding grading (I-IV) and spondyloptosis describe the magnitude of slip. Spinopelvic parameters guide surgical planning in high-grade slips.",
      management:
        "Asymptomatic low-grade slips are managed expectantly with activity modification. Symptomatic patients are offered physiotherapy, analgesia, and epidural injections. Decompression with or without fusion is indicated for persistent radicular symptoms, neurogenic claudication, or progressive slip; recent high-quality trials (SLIP, NORDSTEN) continue to refine the role of fusion versus decompression alone.",
      outcomes:
        "Outcomes after surgery for symptomatic degenerative spondylolisthesis are generally good, with durable improvements in pain and function. Reoperation rates at 5 years range from 10 to 20 percent depending on technique and patient selection.",
    },
  },
  {
    slug: "achilles-tendinopathy",
    name: "Achilles Tendinopathy",
    regionSlug: "foot-ankle",
    category: "Degenerative",
    summary:
      "A degenerative overuse disorder of the Achilles tendon characterised by pain and impaired performance; distinct midportion and insertional subtypes are recognised.",
    sections: {
      overview:
        "Achilles tendinopathy is a failed healing response with disorganised collagen, neovascularisation, and absent classical inflammation. Midportion tendinopathy occurs 2 to 6 cm proximal to the calcaneal insertion; insertional tendinopathy is associated with a Haglund deformity and enthesopathic changes. Risk factors include training errors, calf weakness, metabolic disease, and fluoroquinolone exposure.",
      epidemiology:
        "Lifetime incidence in runners is 10 to 30 percent. Peak age is 30 to 50 years with a male predominance in athletic populations. Incidence rises in sedentary patients after the age of 60.",
      symptoms:
        "Gradual onset of posterior heel or mid-Achilles pain, morning stiffness, and pain at the start of activity that may ease during exercise. Focal tenderness, fusiform thickening, and a positive arc sign help localise pathology. Insertional disease produces calcaneal tenderness and pain with dorsiflexion.",
      imaging:
        "Ultrasound and MRI both demonstrate tendon thickening, hypoechoic or high-signal changes, and neovascularity. Radiographs assess Haglund deformity and calcifications in insertional disease.",
      classification:
        "Anatomical (midportion vs insertional), duration (acute, subacute, chronic), and imaging-based severity are the principal descriptive frameworks.",
      management:
        "Eccentric calf loading (Alfredson protocol) and heavy slow resistance training are the mainstays of treatment, with 60 to 90 percent improvement in midportion disease. Insertional disease responds less well to eccentric loading and may benefit from modified heel-raise programmes and extracorporeal shockwave therapy. Surgical options include debridement, gastrocnemius recession, and FHL transfer for refractory cases.",
      outcomes:
        "Most patients achieve significant improvement with structured loading over 12 to 24 weeks. Outcomes are generally poorer in insertional disease and in patients with metabolic comorbidities.",
    },
  },
  {
    slug: "morton-neuroma",
    name: "Morton's Neuroma",
    regionSlug: "foot-ankle",
    category: "Degenerative",
    summary:
      "A perineural fibrosis of a common plantar digital nerve, most often in the third intermetatarsal space, producing forefoot pain and paraesthesia.",
    sections: {
      overview:
        "Morton's neuroma is not a true neoplasm but a perineural fibrosis with nerve degeneration, most commonly involving the third common plantar digital nerve where medial and lateral plantar contributions converge. Mechanical compression against the deep transverse intermetatarsal ligament and footwear-related forefoot loading are key contributors.",
      epidemiology:
        "Morton's neuroma is much more common in women, with a peak between 40 and 60 years. Narrow or high-heeled footwear is strongly associated. The third web space accounts for 70 to 80 percent of cases; the second web space is less commonly affected.",
      symptoms:
        "Burning plantar forefoot pain radiating into the affected toes, relieved by removing the shoe and rubbing the foot. A positive Mulder click and focal web-space tenderness are characteristic. Sensory symptoms may involve the adjacent toes in the affected web space.",
      imaging:
        "Ultrasound is the imaging modality of choice, sensitive and specific for hypoechoic masses greater than 5 mm. MRI is useful when diagnosis is uncertain or alternative pathology is suspected. Imaging is also useful for guided injection.",
      classification:
        "No formal classification. Descriptive features include web space, size, and response to conservative treatment.",
      management:
        "First-line treatment includes footwear modification (wide toe box, low heel), metatarsal pads, and activity modification. Ultrasound-guided corticosteroid or alcohol ablation injections provide relief in many patients. Surgical excision via a dorsal or plantar approach is indicated for refractory cases, with neurectomy the standard approach.",
      outcomes:
        "Around 50 percent of patients respond to conservative treatment. Surgical excision achieves good or excellent outcomes in 80 percent, with stump neuroma formation and persistent sensory loss as the main complications.",
    },
  },
  {
    slug: "trigger-finger",
    name: "Trigger Finger",
    regionSlug: "hand-wrist",
    category: "Inflammatory",
    summary:
      "Stenosing tenosynovitis of the flexor tendon at the A1 pulley, producing catching, locking, and pain with finger flexion.",
    sections: {
      overview:
        "Trigger finger (stenosing flexor tenosynovitis) arises from a size mismatch between the flexor tendon and the A1 pulley, often with nodular thickening of the tendon. Repetitive grasping and metabolic conditions, particularly diabetes, are strongly associated. Any digit can be affected; the thumb, ring, and middle fingers are most commonly involved.",
      epidemiology:
        "Lifetime prevalence is 2 to 3 percent in the general population and 10 to 20 percent in people with diabetes. Peak incidence is in the fifth and sixth decades with a strong female predominance. Multiple digit involvement is common in diabetic and rheumatoid patients.",
      symptoms:
        "Pain and catching at the A1 pulley, progressive clicking or locking in flexion, and in severe cases a finger locked in flexion requiring passive extension. A palpable nodule is often present at the base of the affected digit.",
      imaging:
        "Trigger finger is a clinical diagnosis. Ultrasound may demonstrate A1 pulley thickening and tendon nodules and is useful when diagnosis is uncertain or for guided injection.",
      classification:
        "Green's classification: grade I (pre-triggering, pain and history of catching), II (active triggering), III (triggering correctable only with passive extension), and IV (fixed locked).",
      management:
        "Splinting and activity modification are useful for early disease. Corticosteroid injection into the flexor sheath achieves resolution in 60 to 90 percent of non-diabetic patients, with lower success in diabetic patients. Percutaneous or open release of the A1 pulley is indicated for refractory or advanced disease, with high success rates.",
      outcomes:
        "Outcomes after injection are excellent in idiopathic cases, with recurrence rates of 20 to 30 percent. Surgical release achieves resolution in more than 95 percent with low complication rates; bowstringing is exceptional when the A2 pulley is preserved.",
    },
  },
  {
    slug: "cubital-tunnel-syndrome",
    name: "Cubital Tunnel Syndrome",
    regionSlug: "elbow",
    category: "Inflammatory",
    summary:
      "Compression of the ulnar nerve at the elbow, producing medial elbow pain, ulnar-sided hand paraesthesia, and eventually intrinsic weakness.",
    sections: {
      overview:
        "Cubital tunnel syndrome is the second most common upper limb compression neuropathy after carpal tunnel syndrome. The ulnar nerve is vulnerable to compression within the cubital tunnel by the arcuate ligament of Osborne, by traction with elbow flexion, and by dynamic subluxation over the medial epicondyle. Chronic compression leads to intraneural oedema, demyelination, and axonal loss.",
      epidemiology:
        "Annual incidence is around 25 per 100,000. Peak age is 40 to 60 years with a male predominance. Occupational and recreational activities that involve prolonged elbow flexion, leaning on the elbow, or repetitive throwing are risk factors.",
      symptoms:
        "Paraesthesia in the ulnar one and a half digits, medial elbow pain, and nocturnal symptoms worsened by elbow flexion. Weakness of grip and pinch, clawing of the ring and little fingers, and a positive Froment and Wartenberg sign develop in advanced disease. The elbow flexion and Tinel tests at the cubital tunnel are supportive.",
      imaging:
        "Electrodiagnostic studies quantify nerve conduction slowing across the elbow and help exclude cervical radiculopathy and thoracic outlet syndrome. Ultrasound and MRI assess nerve morphology, subluxation, and space-occupying lesions.",
      classification:
        "McGowan classification: grade I (mild, paraesthesia only), II (moderate, weakness), and III (severe, intrinsic atrophy). Dellon's modification adds sub-grades.",
      management:
        "Mild and moderate disease is managed with night elbow splinting in extension, activity modification, and nerve gliding. Surgical options include simple in-situ decompression, medial epicondylectomy, and anterior transposition (subcutaneous or submuscular); in-situ decompression is the preferred initial surgical option in most cases. Severe disease and dynamic subluxation may warrant transposition.",
      outcomes:
        "Outcomes correlate with preoperative severity. Mild and moderate cases achieve good to excellent results in around 85 percent, while severe cases with intrinsic wasting have less predictable recovery. Randomised trials show no clear superiority of transposition over simple decompression for typical cases.",
    },
  },
];

export function getConditionBySlug(slug: string): AtlasCondition | undefined {
  return conditions.find((c) => c.slug === slug);
}

export function getConditionsByRegion(regionSlug: string): AtlasCondition[] {
  return conditions.filter((c) => c.regionSlug === regionSlug);
}

export function getConditionCountByRegion(regionSlug: string): number {
  return getConditionsByRegion(regionSlug).length;
}
