Conversion of Failed Hemiarthroplasty to Total Hip Arthroplasty

Abstract

Hemiarthroplasty for femoral neck fractures in elderly is a very common surgery. However, in 20–30 percent of cases, the patient needs revision to total hip arthroplasty (THA). Acetabular erosion, groin pain, femoral stem loosening, dislocation, and periprosthetic fractures are some of the situations where a revision surgery is required. Simple exchange of the acetabular component alone and retaining the stem is possible, but less commonly done. Complete revision of both components is often required for a pain-free stable joint following a failed hemiarthroplasty. This surgery is more complex than primary THA and is comparable to revision THA.

Removal of the existing prosthesis, filling up of bone defects in acetabulum and femur, and restoring biomechanics of the hip with suitable implants are critical steps in this surgical conversion. Meticulous planning is needed to remove the old prosthesis, especially when there is severe protrusio or implant breakage. With a reasonably good surgical technique, the outcome is predictable resulting in a significant improvement in the quality of life of the patient. Dislocation, infection, persistent groin pain, and implant loosening are the most common post-operative complications of the revision surgery. Surgeon’s experience, patient’s comorbidities, and pre-surgical cognitive and physical status are significant factors that influence the outcome of conversion of hemiarthroplasty to THA. Complexities of revising failed hemiarthroplasties are discussed with examples of multiple case studies.