Computer navigated total knee arthroplasty: aspects of a single unit's experience of 777 cases

The use of computer navigation and conventional techniques in total knee arthroplasty remains controversial. Advocates of computer navigated techniques cite better alignment of components and reduced morbidity associated with avoidance of intramedullary instrumentation as a rationale for their use. In contrast, proponents of conventional techniques argue that better alignment does not correlate with a better functional outcome and that the conventional approach avoids the perceived risk of fracture associated with bicortical insertion of navigation tracker pins. All total knee arthoplasties performed at our institution are prospectively monitored for life in a dedicated Joint Replacement Assessment Clinic (JRAC). Patients are reviewed by physiotherapists, independent of the surgeons who performed surgery, both preoperatively and at six weeks, three and six months, and one, two and five years postoperatively (and every five years thereafter). Patients are assessed using validated outcome measures (Knee Society Score, Western Ontario and McMaster Universities (WOMAC) osteoarthritis index, Short Form SF-36 Health Survey (version 2) and a patient satisfaction score). In addition, at 6 months post surgery, a CT scan of each implanted prosthesis is performed using the Perth CT knee protocol. The findings of a single unit's experience of 777 navigated primary total knee replacements are discussed and critically compared to the body of literature that currently relates to this controversial topic.