When is the best time to have your joint replaced?

Whilst this approach is effective in most patients for many years, over time there emerged an increasing proportion of patients in whom these conservative strategies fail and the dilemma of when to have surgery arises.

In that circumstance many a doctor would often refer that decision to the patient, saying ‘let me know when you are ready and I will arrange the operation’.

This is probably the case because clinicians find it very difficult to appreciate on an individual basis the impact of pain and impairment on the quality of life of their patients, despite quantitative methods of measuring quality of life being used in the research arena. As a result, I suspect many a patient chooses to suffer with their pain rather than commit to making such a decision.

Sadly, it is not uncommon for a patient to delay their decision for so long that when they finally choose to have the operation they find that they have developed other health problems which prevents them from proceeding to surgery.

So should clinicians be advocating for joint replacement surgery when symptoms demand rather than leaving it to their patients?

A recent article published in the October issue of the British Journal of Medicine (reference below) adds some interesting results that I feel are worth considering when reflecting on how to address the above question. The researchers evaluated the rate of serious cardiovascular events over 3 years, including cardiac death and myocardial infarction, following joint replacement surgery (of either the hip or knee) in a population of patients with moderate-severe osteoarthritis compared to a similarly affected group who did not undergo surgery. They found that:

• The group who had joint replacement surgery were significantly less likely to experience a serious cardiovascular event (hazard ratio 0.56, p<0.001)
• Absolute risk reduction within 7 years was 12.4% and therefore the number needed to treat with arthroplasty to avoid a serious cardiovascular event was 8
• The significant risk reduction was independent of traditional cardiovascular risk factors.

Therefore, the conclusion of the paper was that primary joint arthroplasty has a cardioprotective benefit in patients with moderate-severe osteoarthritis of the hip or knee. This is reported to be the first time such an effect has been demonstrated.

The reasons that are presented to explain the findings include:

• Physical activity increases following surgery
• Reduction in pain leads to a reduced need for NSAID use and less psychological distress, both of which are thought to increase cardiovascular risk

These results, if replicated by larger longer term studies, would suggest that elective joint replacement surgery should be a term of the past.

Instead the decision to proceed to surgery once conservative therapies have failed is a recommendation made on the balance of health benefits (including a reduction in cardiovascular disease risk) to the short and long term risks of the procedure.

Reference:

1. Ravi B, Croxford R, Austin PC, et al. The relation between total joint arthroplasty and risk for serious cardiovascular events in patients with moderate-severe osteoarthritis: propensity score matched landmark analysis. BMJ 2013; 347: f6187 doi: 10.1136/bmj.f6187