Weight-bearing after ACL reconstruction with or without concomitant injuries: Defining the limits of early mobilisation and safe rehabilitation

Early weight-bearing (WB) after anterior cruciate ligament reconstruction has become a quasi-dogma, largely extrapolated from isolated cohorts with low posterior tibial slope and intact menisci. This editorial argues that such 'early for all' practice is no longer defensible. Instead, weight bearing should be prescribed according to a stratified, lesion- and patient-specific framework. Steep posterior tibial slope, elevated static anterior tibial translation, meniscal root or radial repair, cartilage procedures, and combined procedures fundamentally change the loading vectors acting on the graft and secondary stabilisers. In these scenarios, a short non-WB or protected WB phase appears to improve static laxity without compromising functional recovery. We propose a pragmatic decision model and a simple traffic-light checklist (green/yellow/red) to guide WB timing and magnitude, with patient factors (age, BMI, activity level, compliance) modulating progression within each category. Early weight bearing remains appropriate - and should be pursued boldly - in 'green' isolated ACL knees, but becomes a potentially graft-threatening choice in complex or 'decompensated' knees. Finally, the field must urgently standardise what 'partial' and 'early' WB actually mean and align future trials with quantitative loading, imaging, and functional metrics to move from tradition-based to criterion-based rehabilitation.