What are common indications for revision arthroplasty in the hip?

• A. Osteoarthritis in the contralateral hip
• B. Loosening, infection, dislocation, periprosthetic fracture, malposition, metallosis
• C. Age over 90 alone
• D. Minor wear not affecting function

Answer: (B)

When a hip prosthesis needs to be revised, it’s because the implant has failed or is causing damaging problems around the joint. The most common indications reflect failures of fixation, infection, instability, or adverse tissue reactions. Loosening means the implant is no longer well fixed to the bone, usually with pain and gradual loss of function, and radiographs show lucent lines around the components. Infection, or a periprosthetic joint infection, presents with pain, sometimes drainage or systemic signs, and requires surgical management to eradicate the infection and possibly revise the components. Recurrent dislocation or instability signals that the hip cannot stay in a stable position, often due to malposition, soft-tissue insufficiency, or instability of the bearing surfaces, and revision aims to restore stability. A periprosthetic fracture is a fracture around the implant that threatens the fixation or alignment, needing fixation or revision to allow healing and maintain function. Malposition refers to improper orientation or alignment of the components that leads to abnormal wear or impingement and a higher risk of dislocation, addressed by revision to correct alignment and biomechanics. Metallosis arises from metal wear debris causing tissue reaction and bone loss around the prosthesis, prompting replacement with alternative bearings and thorough debridement.

Conditions like osteoarthritis in the opposite hip, advanced age by itself, or wear that hasn’t impaired function do not constitute indications for revision.