Joint Replacement - Revision Replacement

Revision THR

Few medical interventions have had similar impact on pain and patient autonomy as hip and knee replacement. Total hip replacement is also one of the most cost-effective surgical procedures in medicine. However revision hip replacements are now more frequent as primary hip replacements are being performed for younger, more active patients who tend to "wear out" their prosthesis and the prosthesis becomes loose. These patients also tend to develop osteolysis (bone strength is greatly reduced, especially around the implant) predisposing them to fractures.

Revision total knee replacement

All surgery that involves artificial components has the risks of loosening, wearing out, infection, mal-position, loss of motion, and scar tissue formation. The components can be replaced in case of a failed total knee replacement. Failure may be due to loosening or infection or following a fracture in the periprosthetic region. Loosening is called aseptic if it is due to wear and tear and production of polyethylene debris which in turn causes loosening.. Infective loosening will need two staged exchange of prosthesis.

Infected total knee replacement

Though total knee replacement is a very successful procedure there is a small risk of infection of about 0.5 to 1%. Infection can be classified depending on the chronology of occurrence as,

• Acute – within 6 weeks
• Sub acute- 6 weeks to 3 months
• Chronic- more than 3 months.

Acute infection is confirmed by clinical findings, aspiration and culture of the joint fluid.
Acute infection can be treated with intravenous antibiotics and joint lavage with exchange of insert and retention of the prosthesis. One or two attempts at retention of prosthesis may be successful. Intermittent short course suppressive antibiotic therapy is also helpful in preventing recurrence.
Sub- acute or chronic infection or failure to salvage in acute infection can be treated by two staged revision of the prosthesis. Initial debridement after discontinuation of all antibiotics for a few weeks with multiple intra operative cultures, fixation of antibiotic laden articulating spacer, short course of appropriate antibiotic intravenously followed by oral antibiotics for 8 to 12 weeks followed by second stage revision at present one of the successful protocols.

Two-Stage Revision Hip Arthroplasty

Conventional Total Hip Replacement (THR) is a very successful procedure for the treatment of arthritis of the hip, a condition causing considerable pain and loss of movement. The main complication with Total Hip Replacement using polyethylene cups is that the polyethylene gradually wears, eventually reaching a point where the replacement joint no longer functions properly. The other problem is that although the plastic itself is inert, tiny particles of the plastic are worn away whan the metal rubs against the plastic. This plastic debris can cause an inflammatory reaction and can cause the surrounding bone to be absorbed by the body, leading to loosening of the artificial joint.

Infection remains another complication in hip replacement. We perform a two-staged procedure for these cases with the initial stage comprising of a thorough debridement and antibiotic-impregnated cement spacer application followed by a second procedure involving a redebridement and the insertion of the definitive prosthesis.