Individualized load progression after total knee arthroplasty: an instructional review of enhanced recovery, tissue tolerance, and fibrosis risk

Rehabilitation after total knee arthroplasty (TKA) is a major determinant of pain relief, range-of-motion recovery, gait restoration, patient confidence, and medium- to long-term function. Enhanced recovery after surgery (ERAS) is now widely used as the default perioperative framework for TKA because multimodal analgesia, early mobilization, and coordinated rehabilitation can shorten hospital stay and support early functional independence. However, postoperative tissues do not recover at a uniform pace. Surgical trauma, synovial irritation, soft-tissue tension, pain sensitivity, swelling, and baseline mobility create substantial variation in load tolerance. In this instructional review, we synthesize clinical and mechanistic evidence on tissue repair, mechanical loading, postoperative stiffness, and fibrosis-prone recovery after TKA. We propose an individualized load-progression framework in which ERAS remains the main pathway for uncomplicated patients, whereas temporary protective load de-escalation is reserved for patients whose recovery trajectory suggests load mismatch, including pain rebound, persistent swelling, range-of-motion stagnation or regression, increased soft-tissue tension, or declining rehabilitation tolerance. Protective load modulation should be short-term, activity-preserving, dynamically reassessed, and followed by timely return to progressive active rehabilitation once symptoms stabilize. Because direct evidence that this approach prevents arthrofibrosis remains limited, the framework should be interpreted as a clinically grounded, hypothesis-generating model that requires prospective validation.