Rehabilitation Principles

Rehabilitation is the main treatment for most musculoskeletal conditions, not an add-on to other interventions. Its central principle is progressive loading: tissues adapt to the loads placed on them, so graded mechanical stress drives remodelling and restores capacity.

Prolonged rest causes deconditioning and is rarely appropriate. Modern practice favours early active loading, criteria-based return to sport and a biopsychosocial approach. The goal is load tolerance, not pain elimination.

Soft tissues heal in overlapping phases whose timing varies with the tissue and the severity of injury. As a guide:

• •Inflammation (the first few days, peaking around 72 hours): neutrophils, then macrophages that clear debris and release growth factors. It is a necessary step in repair.
• •Repair (from about 72 hours, typically for 3 to 6 weeks): fibroblasts lay down weaker type III collagen. Early controlled loading aligns it along lines of stress (Davis's law).
• •Remodelling (from several weeks to 12 months or more): stronger type I collagen replaces type III. Stopping rehabilitation once the patient feels better is a common cause of recurrence.

Muscle heals relatively well over weeks to months, and tendon slowly over months. Ligament heals with weaker scar, bone remodels under load (Wolff's law; most stress injuries take 6 to 12 weeks), and articular cartilage barely heals, although cyclic loading keeps it healthy.

Injury occurs when load exceeds capacity. Rehabilitation builds capacity until it exceeds the demands of sport, not merely matches them.

Rest deconditions quickly: muscle atrophies within days (type II fibres fastest), proprioception declines and cardiovascular fitness drops within 1 to 2 weeks. In persistent pain, central sensitisation amplifies pain beyond the tissue state, so management shifts towards education and graded exposure.