Partial Knee Replacement

I’m 59 years old and was diagnosed with moderate arthritis in my right knee several years ago and the pain is worsening on the inside of my knee. How do I know when its time for surgery and is a complete knee replacement likely to be my only option?

The severity of knee arthritis exhibited on standing X-rays does not always correlate well with patients’ symptoms. Imaging studies may document that the cartilage surface is essentially absent in a specific region of your knee, but pain may range from mild to severe. In addition, degenerative or osteoarthritis may flare and become more severe for several months and then settle back down to baseline. Anti-inflammatory measures including ice, non-steroidal anti-inflammatory medications, and decreasing demands on your knee may help alleviate symptoms. Cortisone injections and occasionally viscosupplementation (includes a form of hyaluronic acid normally found in your knee) may also be helpful in the short to intermediate time frame. Occasionally bracing can unload a region of your knee if the pain is localized.

When conservative measures fail to provide acceptable relief, surgery may be the most appropriate option – your answer to 3 questions can help you decide if you are ready. 1) Is your quality of life unacceptably compromised by your knee symptoms (pain, stiffness, swelling, etc.)? 2) Has it been at least 6 months in that unacceptable condition? 3) Have you tried other, simpler and less invasive treatment options without success? When the answer to all 3 questions is “Yes”, you are likely an appropriate candidate for surgery assuming other health issues don’t make the risks of surgery unacceptable.

The knee is considered to have 3 compartments – inside (medial), outside (lateral), and kneecap / thigh bone (patellofemoral). If your arthritis is predominantly in one compartment and the integrity of the other areas is reasonably well preserved, a partial knee replacement (Unicompartmental) may be an attractive option. Only the surfaces of your knee in the involved compartment are replaced. Typically the extent of the surgical exposure is less, you can bear weight immediately, and the odds are better than 50:50 that the procedure is performed on an outpatient basis. All of your own normal ligaments are preserved during a partial knee replacement, which tends to make your knee feel ‘more normal’ after recovery than a complete knee replacement. Most patients are walking relatively comfortably after 4 – 6 weeks and often return to activities such as golf (using a cart) at 3 months. If you are an appropriate candidate for a unicompartmental knee replacement, you can expect to have a high probability that most if not all of your pain will be resolved and that you can return to an active, healthy lifestyle. A normally aligned knee with a partial replacement can be expected to function well for 12 – 15 years and possibly longer.