Correspondence should be sent

This editorial considers the shortcomings of assessing outcome after joint replacement only by the survival of the implant. Survivorship of a prosthesis is used as an objec-tive outcome measure to determine whether surgery has been a success or a failure. It is clearly important to know the length of time that an implant has remained in place so that any early failure of a new implant may be iden-tified. However, to define a successful outcome solely on implant survivorship is inadequate and lacks sensitivity. Because revision is uncommon, large sample sizes and long-term follow-up are needed to detect significant dif-ferences in survival rates between implants.1 If an operation is only defined as having failed i