Successful recovery following a total hip replacement (THA) relies heavily on movement. Physical activity is fundamental for regaining strength and mobility in the muscles surrounding the new joint. Engaging in prescribed movements also helps prevent post-surgical complications, such as deep vein thrombosis (DVT), by promoting blood circulation in the lower limbs. Patients must follow the specific instructions provided by the surgeon and physical therapist to ensure exercises are performed safely and appropriately for their individual recovery timeline.
Exercises in the Immediate Post-Surgical Phase
The initial exercises begin almost immediately after surgery, often while the patient is still in the hospital bed. These gentle movements are designed primarily for circulation and muscle re-activation, helping to maintain blood flow and prevent blood clots. The most frequent movement prescribed is the Ankle Pump, which involves repeatedly pointing the foot up toward the head and then down away from it. This action contracts the calf muscles, aiding the return of venous blood flow to the heart.
Simultaneous muscle activation helps re-establish the mind-muscle connection. Quadriceps Sets require the patient to tighten the thigh muscle on the front of the leg, pushing the back of the knee down gently into the mattress. This isometric contraction strengthens the quadriceps without moving the hip joint itself. Another isometric exercise is the Gluteal Set, where the patient squeezes the buttocks together and holds the contraction for a few seconds. Early mobilization, including transferring from bed to a chair and short, assisted walks, begins within the first day or two to promote joint lubrication and increase independence.
Foundational Home Strengthening (Weeks 1-6)
The first six weeks of recovery focus on regaining basic strength and controlled range of motion within prescribed limits. These exercises are performed slowly and deliberately to rebuild the supporting musculature around the hip joint. The Heel Slide facilitates gentle hip and knee flexion by sliding the heel of the operated leg toward the buttocks, keeping the heel in contact with the surface. This controlled movement improves the ability to bend the hip while remaining within the safe range of motion.
Standing exercises are introduced using a stable support, such as a counter or chair, for safety. Standing Hip Abduction involves slowly lifting the operated leg straight out to the side, keeping the toes pointed forward. This targets the gluteus medius, which stabilizes the pelvis during walking. Standing Hip Extension requires moving the operated leg straight backward, engaging the gluteus maximus to restore power for pushing off during the gait cycle. Maintaining a proper walking gait is also a focus, ensuring the patient steps with a heel-toe pattern and progressively increases walking distance.
Advancing Functional Movement (After 6 Weeks)
After the initial healing period is complete and clearance is provided, typically after six weeks, the program progresses to more complex, functional movements. This stage aims to restore the strength and endurance required for a return to daily and recreational activities. Light Squats, or mini-squats, are introduced to strengthen the large muscle groups of the legs. The movement must be performed cautiously, only bending the knees slightly and ensuring the hips do not flex past the 90-degree limit.
Step-Ups require the patient to step up onto a low step using the operated leg and then step back down in a controlled manner. This activity simulates climbing stairs and builds power and endurance in the hip and thigh muscles. Single-Leg Stance exercises challenge the balance and proprioception of the hip joint, which is necessary for walking without an assistive device. Low-impact cardiovascular activities, such as cycling on a stationary bike or swimming, are encouraged to build endurance without stressing the new joint.
Crucial Hip Precautions
Adhering to specific movement restrictions after hip replacement surgery is necessary to prevent the artificial joint from dislocating. The risk of dislocation is highest in the initial weeks following the procedure while the soft tissues surrounding the joint heal and the surrounding muscles regain strength.
The three primary precautions are:
- Avoiding excessive hip flexion, meaning the hip should not bend more than 90 degrees. Practical applications include using a raised toilet seat, avoiding low chairs, and not bending over to pick up objects from the floor.
- Avoiding the crossing of the operated leg past the midline of the body, whether sitting, standing, or lying down. Patients are often advised to use an abduction pillow between the legs when sleeping to ensure the legs remain separated.
- Avoiding internal rotation of the hip, which means the foot and knee of the operated leg should not turn inward. Patients should keep their toes pointed forward or slightly outward during movement and use small steps when turning.