Bilateral knee joint replacement

Bilateral knee joint replacement under the same anaesthesia has been a controversial management option for patients suffering from osteoarthritis of both knees, and the worldwide experience is limited. While practised in some national and international centres over the last decade and a half, the major concern revolves around perioperative morbidity. Indeed, the initial reports of published series suggested that cardiovascular upset was a significant risk for bilateral simultaneous surgery, and that appropriate patient support was required to minimize and to expeditiously correct poor outcomes^1,2. Improvements in anaesthesia, recognition of the risks of bilateral simultaneous surgery, prophylactic intervention and faster surgical techniques have once again raised this option; but now also with the added pressure of economic rationalization.

In the current issue of the Journal, Horne et al.³ and Stubbs et al.⁴ conclude that, in their hands, bilateral simultaneous knee joint replacement is a relatively safe procedure. Both groups have concluded that their results not only support the adoption of this technique but also substantiate their decision on economic grounds. Indeed, this latter sentiment was strongly expressed in the closing passages of their respective articles.

The experiences of Horne et al.³ and Stubbs et al.⁴, while limited in numbers, demonstrated no significant increase in perioperative morbidity following bilateral simultaneous knee joint replacement. The authors focused on the early cardiovascular, respiratory and mental complications of surgery and found no difference to those reported in historical or unmatched single-knee or staged-bilateral-knee replacement groups. It is important to note, however, that both groups presented retrospective data, and the lack of adequate control groups in both series is a major weakness that should temper their results. Indeed, in neither series was there information that highlighted the selection criteria nor more importantly, the exclusion criteria; particularly as the literature has underscored the apparently higher risks associated with this procedure.

There is no question that most if not all hospitals, both public and private, operate under considerably more financial pressures today than before. The growing demand and costs for services when coupled with an increasingly limited opportunity to deliver has compelled health economists to review the work of surgeons and surgery itself. Recognizing this to be the case, Horne et al.³ and Stubbs et al.⁴ should be congratulated for continuing to focus on the quality of service and outcomes in their reviews. They have highlighted the importance of all surgeons undertaking reviews of quality and outcome measures, particularly when there are external economic forces applied to curtail established practises in the name of ‘best practice’ or ‘improving patient flows’.

The works of Horne et al.³ and Stubbs et al.⁴ should be the forerunner to randomized, controlled, prospective studies to assess the safety and efficacy of bilateral simultaneous knee joint replacement. The Australian Joint Replacement Registry now reports the implantation of thousands of knee prostheses each year. This would suggest that a multi-institutional trial could be assembled with sufficient statistical rigour to provide a result that would have not only international import, but also the opportunity to demonstrate the very high standard of trans-Tasman clinical practice. To date, there is no such trial, and what approaches this is disappointingly limited. Until then, surgeons aiming to perform bilateral simultaneous knee replacement should ensure their patients undergo appropriate preoperative screening to minimize the reported perioperative risks of cardiorespiratory, and central neurological compromise that is associated with the physiological upsets known to occur with this procedure.