Physical therapy (PT) is an active approach to healing focused on restoring function, strength, and mobility following an injury or illness. It involves guided exercises, hands-on techniques, and specialized modalities to promote tissue repair and reduce pain. The timing of when this rehabilitation begins is highly dependent on the nature and severity of the injury, making the concept of a universal starting point impossible.
The General Guidelines for Timing
The body’s natural healing process dictates the initial approach to physical therapy, which moves through distinct phases following trauma. The first stage is the acute phase (24 to 72 hours), characterized by significant pain, swelling, and inflammation. During this period, the focus is on protection and managing symptoms; active rehabilitation is generally not appropriate, though gentle, passive movements may be introduced.
The transition to the subacute phase, usually beginning a few days to a week after injury, marks the optimal window for starting controlled physical therapy. For common soft tissue injuries, such as a mild ankle sprain or muscle strain, starting an evaluation shortly after acute symptoms resolve is recommended. Early, protected movement initiated in this phase helps prevent excessive stiffness and promotes the proper alignment of new collagen fibers as the tissue begins to repair itself. This initial therapy is distinct from intense rehabilitation, focusing on pain-free range of motion and preparatory exercises.
Factors Determining the Optimal Start Date
The type and extent of tissue damage are the most significant variables determining the timeline for therapeutic movement. Soft tissue injuries (ligaments, tendons, or muscles) generally benefit from early intervention to maintain flexibility and promote blood flow. For example, some simple muscle strains may begin passive mobilization as early as three days after the injury, with controlled, active exercises starting within five to seven days, using pain as the primary guide for progression.
Injuries involving bone, such as fractures, necessitate a longer period of rest and immobilization for adequate structural healing. Physical therapy must be delayed until the bone has achieved sufficient stability, which can be several weeks or longer, depending on the fracture site. For instance, a complex femur fracture may require six to twelve weeks before significant weight-bearing activities can safely begin under a therapist’s guidance.
When an injury requires surgical repair, the surgeon provides the definitive clearance for starting physical therapy, strictly based on the integrity of the repaired tissue. For some procedures, such as certain knee surgeries, therapy may begin immediately post-operation to protect the joint’s mobility. Conversely, delicate repairs like those for a rotator cuff often require a delay of four to six weeks to protect the sutures and allow the tendon to begin healing before any active movement is introduced.
Uncontrolled inflammation and severe pain serve as temporary contraindications for active rehabilitation. If the inflammatory response is too intense, initial physical therapy focuses on preparatory measures, such as pain-reducing modalities or passive range-of-motion exercises, rather than active strengthening. The body must move past the most acute stage of swelling and pain to tolerate therapeutic movements that promote long-term recovery.
The Risks of Delaying Rehabilitation
Postponing physical therapy past the optimal window leads to physiological changes that complicate and prolong recovery. One consequence of prolonged immobilization is muscle atrophy, where muscle mass and strength waste away. This weakening of the surrounding musculature makes the area less stable and more vulnerable to re-injury once activity resumes.
Delaying movement encourages the formation of restrictive scar tissue (fibrosis), which limits the joint’s natural movement. Without controlled, guided motion, the newly formed collagen fibers heal in a disorganized pattern, leading to stiffness and a reduced range of motion, which is harder and more painful to correct later.
Furthermore, a lack of early, correct movement can cause the body to develop compensatory movement patterns, where other muscles and joints take over the work of the injured area. These altered mechanics place abnormal stress on healthy areas, potentially leading to new injuries or the original issue becoming a chronic problem.