Title: Critical evaluation of results of total knee replacement by computer navigation technology.

Objective:The procedure of TKR consists of joint articular surface replacement with a knee prosthesis whose positioning has been conventionaIly performed with the use of intramedullary or extramedulIary alignment. More recently, computer­ assisted systems have been developed to improve the positioning of the prosthesis components with the goal of improving the postoperative prosthesis alignment, which in turn improves the overall survivorship of the prosthesis.

Methods:This study was a prospective type of interventional clinical study. The study was conducted in the department of orthopaedics of Santokba durlabhji memorial hospital cum medical research institute jaipur. 20 consecutive patients of osteoarticular disease of knee with proven diagnosis of severe arthritis, diagnosed radiographically and clinically were selected and computer Assisted total knee arthroplasty performed. All the patients were evaluated for clinical, functional and radiological status according to knee society scores.

Results: There were total 20 patients out of them 5 were male and 15 were female.Overall the mean age of total knee arthroplasty was 62.85 years. 28 knees out of the 34 were replaced bilaterally and 06 replaced unilaterally. Average follow–up was 12 months. Main indication of total knee arthroplasty was severe pain. After total knee arthroplasty 16 knees had no pain and 15 knees had mild pain.The mean preoperative knee society pain score was 11.76 and postoperative pain score was 42.50. The mean preoperative range of movement before TKA was 96.32 degree and after total knee arthroplasty mean ROM was 116.47 degree. There was statically significant improvement present in functional score after total knee arthroplasty.

Conclusion: With the better understanding of biomechanics of knee, availability of newer prosthesis, newer technique like computer navigation system has led to good clinical and functional outcome. There is accurate restoration of mechanical limb axis by the computer navigated total knee arthroplasty.