Can computer assistance improve the clinical and functional scores in total knee arthroplasty?

BACKGROUND: Surgical navigation in TKA facilitates better alignment; however, it is unclear whether improved alignment alters clinical evolution and midterm and long-term complication rates.

QUESTIONS/PURPOSES: We determined the alignment differences between patients with standard, manual, jig-based TKAs and patients with navigation-based TKAs, and whether any differences would modify function, implant survival, and/or complications.

PATIENTS AND MATERIALS: We retrospectively reviewed 97 patients (100 TKAs) undergoing TKAs for minimal preoperative deformities. Fifty TKAs were performed with an image-free surgical navigation system and the other 50 with a standard technique. We compared femoral angle (FA), tibial angle (TA), and femorotibial angle (FTA) and determined whether any differences altered clinical or functional scores, as measured by the Knee Society Score (KSS), or complications. Seventy-three patients (75 TKAs) had a minimum followup of 8 years (mean, 8.3 years; range, 8-9.1 years).

RESULTS: All patients included in the surgical navigation group had a FTA between 177° and 182º. We found no differences in the KSS or implant survival between the two groups and no differences in complication rates, although more complications occurred in the standard technique group (seven compared with two in the surgical navigation group).

CONCLUSIONS: In the midterm, we found no difference in functional and clinical scores or implant survival between TKAs performed with and without the assistance of a navigation system.

LEVEL OF EVIDENCE: Level II, therapeutic study. See the Guidelines online for a complete description of levels of evidence.