Preliminary clinical effects of total knee arthroplasty with iASSIST navigation system

Objective To explore the application value of iASSIST portable navigation in total knee arthroplasty. Methods Seventy-four patients with knee osteoarthritis from April 2016 to April 2017 were retrospectively recruited. Thirty-seven patients (37 knees) underwent TKA with iASSIST navigation, while 37 patients (37 knees) underwent conventional TKA. Five parameters were measured on the weight-bearing radiographs at six months after TKA, including mechanical axis (MA), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), sagittal femoral component angle (sFCA) and sagittal tibial component angle (sTCA). Duration of operation, blood loss volume, postoperative hospital day, Western Ontario and McMaster Universities (WOMAC) osteoarthritis index, Knee Society Score (KSS) clinical score and functional score at 6 weeks, 12 weeks and 24 weeks after surgery were also recorded. Results The accuracy of MA (180.85°±0.88° versus 182.23°±1.09° in the conventional group, P 0.05). Conclusion More accurate restoration in mechanical axis and optimal implantation can be achieved with the help of iASSIST navigation. This navigation system can also achieve better knee function in the early stage after TKA. Key words: Osteoarthritis, knee; Arthroplasty, replacement, knee; Surgery, computer-assisted; X-rays