SHORT-TERM RESULTS OF CRUCIATESUBSTITUTING CEMENTED TOTAL KNEE ARTHROPLASTY

Background: Total Knee Arthroplasty(TKA) is indicated in individuals with painful, disabling arthritis, having radiographic evidence of joint damage and not responding to conservative treatment, thus resulting in diminished quality of life. The goal of TKA is to relieve pain, provide motion, maintain stability and correct deformity. Aim: To evaluate short-term clinico-radiological results and complications of TKA. Material and methods: A prospective randomized controlled study was conducted between December 2006 and June 2009 on 41 patients(61 knees) who underwent TKA and were followed for one year or more. Mean follow-up was 19.69±5.69 months (minimum-12, maximum-30). Posterior Cruciate Ligament (PCL)- substituting cemented Press Fit Condylar(PFC) Sigma prosthesis(Depuy Orthopaedics) was used in all cases. Fixed-bearing design was used in 39 patients(57 knees) while mobile-bearing rotating-platform design(PFC-sigma-RP) was used in 2 patients(4 knees). Patella was resurfaced in 2 patients(2 knees). Pain(using Visual analogue scale-VAS), fixed flexion deformity(FFD), maximum flexion and Knee Society Score(KSS) were evaluated preoperatively and postoperatively. Radiological analysis included assessment of femoral-tibial alignment, radiolucencies and patellar tracking. Changes at 3, 6, 12 and 24 months were statistically analyzed. Observations and results: Mean age was 61.17 ± 9.51 years(range 40- 77 years). Male to female ratio was 1:2.4. Osteoarthritis(OA) with varus deformity was present in majority. By the end of 1 year, most patients had either no pain or only mild occasional pain. Preoperatively 93% patients had poor functional score(FS) and 98% knees had poor knee score(KS). After TKA, about 85% patients had excellent or good FS while nearly 97% knees had excellent or good KS. Near maximum improvement in KSS is achieved by the end of 1 year with no further significant improvement thereafter. The mean maximum flexion was 114.750 preoperativly and 113.770 at 1 year which was not statistically significant. There were very few complications. Infection was present in 3 cases while peroneal nerve palsy in one. There were no progressive radiolucencies, polyethylene wear, implant failure, patello-femoral complications or clinical deep venous thrombosis(DVT). One knee with mobilebearing prosthesis had insert spin-off after 2 weeks. Conclusion: TKA is a very successful, safe and costeffective treatment for patients with knee arthritis who do not respond to nonsurgical therapies. Cemented TKA is still the gold standard and fixedbearing, cruciate-substituting prosthesis continues to function well after 2-years of follow-up. Keywords: Knee arthritis, cemented cruciate-substituting Total knee arthroplasty, short- term results.