Is a total knee replacement (TKR) inevitable for someone with painful knee OA? The lifetime prevalence of TKR is 18-30%, hardly a guarantee, but with life expectancy increasing and risk factors worsening (e.g., inactivity, obesity, diabetes) it’s likely those numbers with rise. Previous evidence suggests rehabilitation may be an effective alternative, however, we lack long-term outcome data. One study showed substantial improvements following a non-op approach in patients who were deemed ineligible for TKR, and those improvements were sustained for 2 years. That is a solid start, but a two-year delay won’t get many patients excited. I’m not saying everyone gets surgery after the two-year delay, we simply don’t know the outcomes after two years. This new study (PMID: 36428014) brings our knowledge base up to 5 years post non-op treatments.
One of the limitations of the study is the patient population. They only included patients who were denied TKR due to lack of severity (pain, function, and radiograph severity). It would be helpful to know the effects and durability of non-op care in patients deemed eligible for TKR. Regardless, this provides us with more information on the durability of outcomes for people with knee OA. The non-op patients were allocated to a written advice group or a 12-week supervised exercise group (who also received the written advice, making this an a vs. a+b trial…another limitation). The exercise program group received patient education, neuromuscular exercise, insoles, a dietary weight loss program (if baseline BMI was >25), and/or pain meds if needed to participate in the exercise.
At all checkpoints up to 2 years, the exercise group was superior, however, the difference disappeared at the 5-year mark. Regardless of the intervention, patients saw improvements, building off of previous research that challenges the notion all OA progressively worsens. With only 50-patient groups and wide confidence intervals, we cannot say all patients will have equivalent outcomes 5 years after discharge from non-op treatment. We also don’t know the exercise habits of the patients after discharge, their strength, or their muscle mass. We are left with many questions, but we do have some data to show knee OA can improve over time non-operatively.