A broken leg requires a structured process known as rehabilitation to restore the limb’s function and prepare the person for a return to everyday activities. This process is necessary because the period of immobilization, whether in a cast, brace, or surgical boot, causes the surrounding joints to stiffen and the leg muscles to weaken significantly. Rehabilitation is a carefully timed sequence of physical therapy that begins after the bone has stabilized sufficiently to tolerate movement, using a progressive approach to rebuild strength, flexibility, and coordination. The ultimate goal is not simply to heal the bone, but to ensure the entire leg can perform all previous functions without pain or lasting limitation.
The Initial Phase: Addressing Swelling and Stiffness
The first sessions of physical therapy, immediately following the removal of the immobilization device, concentrate on minimizing the effects of the prolonged rest period. A primary concern is managing residual pain and inflammation, often addressed using modified R.I.C.E. principles: rest, ice, compression, and elevation. Applying ice and elevating the leg helps to reduce swelling, which can otherwise restrict movement and cause discomfort. The therapist may use specific techniques to control inflammation, allowing for a smoother transition to movement-based exercises.
Stiffness in the joints adjacent to the fracture site, such as the ankle or knee, is expected after weeks of being held still. The first movements are typically gentle, passive range of motion exercises, where the therapist or a specialized machine moves the joint without the patient activating their muscles. This technique, sometimes called passive mobilization, safely introduces movement to lubricate the joint and prevent contractures. This establishes a foundational level of flexibility and prepares the soft tissues for more demanding work.
Developing Strength and Active Range of Motion
Once the initial swelling and tenderness have subsided, the focus shifts to actively engaging the muscles and increasing the amount of movement the patient can generate on their own. This phase marks the move from passive movement to active range of motion, where the patient uses their own muscle power to move the joint through its available arc. This active participation is crucial for stimulating the nervous system and re-establishing the connection between the brain and the injured limb. The therapist guides the patient to perform movements such as ankle circles, toe curls, and gentle knee flexion and extension, ensuring all movements remain within a pain-free range.
The muscle atrophy that occurs during immobilization must be reversed through targeted strengthening exercises. The primary targets are the major muscle groups of the leg: the quadriceps, hamstrings, and calf muscles. Early strengthening often involves isometric exercises, where the muscle is contracted without moving the joint, such as tightening the thigh muscle while the leg remains straight.
As strength improves, resistance is introduced using tools like light handheld weights, ankle cuffs, or elastic resistance bands. Resistance band exercises are particularly useful for strengthening the muscles around the ankle, targeting movements like dorsiflexion, plantar flexion, inversion, and eversion.
Reintroducing Weight-Bearing and Functional Gait Training
With sufficient strength established, the rehabilitation program moves into the functional phase of safely reintroducing weight-bearing and retraining the body to walk normally. The progression of weight-bearing is strictly guided by the surgeon and physical therapist, moving from non-weight-bearing to partial weight-bearing (PWB), and finally to full weight-bearing (FWB). PWB may begin by allowing the patient to place a specific percentage of their body weight, perhaps 25% or 50%, onto the injured leg, often measured with the aid of a scale or specialized sensor.
Assistive devices, such as crutches, a walker, or a cane, are used throughout this phase to protect the healing bone and provide stability as the person transitions to walking. Functional gait training involves relearning proper gait mechanics, which may have been disrupted by the injury and subsequent limp. The therapist works with the patient to ensure proper stride length, heel-to-toe pattern, and symmetrical weight distribution, which prevents compensatory habits that can lead to pain in the back or opposite leg.
Balance and proprioception exercises are also integrated into this stage to improve stability and prevent future falls. Proprioception is the body’s awareness of its position in space, which is often diminished after a joint injury or period of disuse. Exercises may start simply, such as standing on one leg while holding onto a stable surface, and progress to more complex tasks. These include walking heel-to-toe, standing on uneven surfaces like foam pads, or using balance boards.
Assessing Progress and Transitioning Out of Formal Therapy
Progress is continually monitored using a combination of objective measurements and functional assessments to ensure the patient is meeting established goals. Objective measures include using a goniometer to precisely track the joint’s range of motion and employing a dynamometer to quantify muscle strength. Pain levels are also tracked using standardized scales, providing a subjective measure of recovery.
Functional outcome measures simulate real-world activities to determine progress. Tests like the Timed Up and Go (TUG) assess mobility and balance by timing how long it takes to stand up, walk a short distance, turn, and sit back down. These scores are compared against baseline measurements and established norms to determine when the patient has reached a level of function that makes formal therapy unnecessary.
Discharge from formal physical therapy occurs when the patient has met their functional goals and can safely manage their recovery independently. A home exercise program is provided to ensure continued gains, even after the bone has healed and the patient is walking without an assistive device. This program maintains the strength and flexibility achieved in therapy, preventing regression. For individuals returning to high-impact activities or sports, the therapist may provide a final, advanced phase of sport-specific training.