Title : Rehabilitation protocols following anterior cruciate ligament reconstruction versus primary repair: A criteria-based approach
Abstract:
Background: Return to safe, functional sport after ACL surgery depends as much on the rehabilitation pathway as on the surgical technique. Recent interest in primary ACL repair for selected proximal tears has renewed the need to define pragmatic, evidence informed rehab pathways that reflect differences in tissue healing, graft biology, and early stability between reconstruction and repair.
Objective: To present a concise, clinically usable, criteria based rehabilitation protocol covering early protection, progressive loading, neuromuscular retraining, and return to sport criteria tailored separately for ACL reconstruction (ACLR) and arthroscopic primary ACL repair (ACLRp), highlighting where timelines and milestones should diverge.
Methods: We combined contemporary evidence and commonly used institutional protocols to produce parallel, milestone led pathways. Protocol stages are Immediate (0–2 weeks), Early Recovery (2–6 weeks), Strength & Control (6–12 weeks), Advanced Conditioning (3–6 months) and Return to Sport (criteria based, typically ≥6 months). For each stage we specify goals (pain/effusion control, ROM, gait, quadriceps activation), safe progression of weightbearing and range of motion, key exercises, and objective criteria (strength symmetry, hop testing, movement quality) that guide progression rather than rigid time points.
Results: Early motion and accelerated weightbearing are encouraged after successful arthroscopic primary repair when tissue quality and fixation are reliable, often allowing faster restoration of range of motion and quadriceps activation compared with reconstruction; nevertheless, repair pathways require careful monitoring for elongation or failure and a slightly more conservative approach to high grade pivoting drills until healing is confirmed.
ACL reconstruction protocols focus on protecting graft fixation and optimizing graft maturation progression to high velocity cutting and pivoting is generally more conservative and driven by objective strength and functional tests (commonly ≥90% limb symmetry on strength and hop testing). Both pathways emphasise early neuromuscular training, progressive eccentric and closed chain quadriceps loading, and psychological readiness as essential components to reduce re injury risk and optimise return to sport outcomes.
Conclusion: A criteria based rehabilitation framework that distinguishes biological and mechanical differences between ACL reconstruction and primary repair produces clearer guidance for clinicians and patients, supports safer progression through sport specific demands, and prioritises objective milestones over fixed timelines. Implementation requires close surgeon–physiotherapist communication and routine objective testing to personalise progression and identify early signs of failure or delayed recovery.
Keywords: ACL rehabilitation; ACL reconstruction; primary ACL repair; return to sport; criteria based protocol.
