Patient demand matching in total knee arthroplasty: is it necessary?

Patient demand matching has been accepted as an appropriate method of implant management by hospitals for cost reduction. However, there have been no prospective studies to substantiate whether these patients change their demand levels postoperatively. Theoretically, functional activity levels should not increase significantly postoperatively in patients with preoperative low demand levels for patient demand matching to be effective in avoiding premature prosthetic failure. Preoperative and postoperative demand levels were prospectively reviewed in 279 patients undergoing total knee arthroplasty (TKA). Preoperatively, the medium/high-demand patients performed significantly more activities overall than low-demand patients. Postoperatively, both low- and medium/high-demand patients dramatically increased the number of activities performed. The hypothesis that prosthetic choice should be determined by preoperative activity level (demand matching) was not validated by this study because patient activity levels significantly increased in all categories subsequent to TKA.