Hip Replacement Complications & Risks
The complications associated with hip replacement surgery although rare may at times require revision surgery. The complications may occur during the surgery, immediately after the surgery or after weeks, months, or years after the surgery.
Total hip replacement dislocation
Dislocation may occur when the ball of the prosthetic joint pops out of the prosthetic socket. Majority of the total hip dislocation occurs in the first month following the surgery. Total hip dislocation occurs more frequently following the use of the posterior approach as compared to the anterior approach.
Patient factors such as a prior hip surgery, elderly age, a history of alcoholism or drug abuse, and any neuromuscular disease such as Parkinson’s increase the risk for total hip joint dislocation.
Surgery factors include mal-position of the implant, inadequate repair of the soft tissues following the surgery. Noncompliance with the hip dislocation precautions immediately following the surgery also increase the risk for dislocation.
The management of dislocation following surgery is generally non operative but may require repeat surgery if dislocation is due to mal-position or wear of the plastic cup. Two or more dislocations need a revision surgery and may require the use of special implants to prevent future dislocation.
Periprosthetic fracture is the break in bone surrounding the implant. The break may be in the bony acetabulum or the bony femur hosting the stem of the prosthesis. The fracture may occur during the surgery or may occur after the surgery.
While some stable fractures may be observed, the majority of the unstable fractures may require revision surgery. The surgery for periprosthetic fracture may require use of additional implants with plates, wires or screws.
Sciatic nerve palsy
Sciatic nerve is a large nerve that originates from the nerve roots in the lower spine. The nerve travels in the buttock behind the hip joint and supplies to the major muscles in the back of the thigh, calf and the foot.
Due to the proximity of the nerve to the hip joint, the nerve is often exposed during the posterior approach to the hip joint. The nerve is gently retracted back and is protected by the external rotator muscles.
The nerve may be damaged due to excessive pressure during retraction, direct injury to the nerve, lengthening of the leg, formation of blood collection, and in majority of the cases, the cause is unknown.
The patient may present with numbness, paresthesia, or inability to lift the foot up (foot drop). The treatment may include use of ankle foot orthotics until the nerve recovers.
The implanted prosthetic components may become loose secondary to aseptic loosening. Aseptic loosening occurs due to the body’s cells (macrophages) fighting against the microscopic particles released by the implanted components. The resulting inflammation may cause erosion of the bone around the implant leading to loosening. The management is usually surgical in the form of revision surgery.
There may be a leg length discrepancy following the surgery. Leg length discrepancy may occur as a result of operative techniques, contracture (fibrosis) or weakness of the muscles around the hip joint. At times, the patients may simply perceive the leg to be longer/shorter despite equal anatomical length. A shoe lift is generally helpful in resolving small discrepancies. A revision surgery may rarely be required for large discrepancy.
There may be impingement of the iliopsoas tendon as it passes in front of the prosthetic joint. The iliopsoas tendon connects the iliopsoas muscles to the upper part of the femur. The tendon may impingement and cause groin pain especially during movement. The impingement may occur as a result of mal-position of the acetabulum implant, or due to the surgical technique. The management is generally surgical.
Prosthetic joint infection
Infection is a dreaded complication of hip replacement surgery and may require prolonged use of antibiotics and staged revision surgeries.
Formation of bone tissue in the muscles surrounding the hip joint is a complication that may severely limit movement of the joint and cause pain. The cause of ossification may be linked to excessive surgery time and handling of the soft tissues during surgery. The management is generally surgical.
Hip replacement surgeries are the most successful surgeries in modern medicine. The complications are rare but should be discussed with your operating surgeon.