Computer-Assisted Surgery in Total Knee Arthroplasty: Our Experience

Total knee arthroplasty (TKA) is a reliable orthopedic procedure for knee osteoarthritis with long-term success rates of 90% after 15 years. Computer-assisted surgery (CAS) has been developed to improve the accuracy of the alignment and orientation of the components in TKA.

A prospective study involving 103 subjects who underwent CAS–TKA was conducted over a 3-year period. Subjects were assessed for pre- and post-operative varus and valgus deformity, BMI, comorbidities, and Knee Society Score (KSS). Outcome measures of post-operative KSS, post-operative alignment, and hospital stay were examined by Spearman correlation coefficients. Categorical outcomes of complication and secondary procedures were compared by chi-squared test and odds ratio.

The study considered 103 TKA patients with a mean ± SD age of 63.7 ± 8.4 years (33–88 years). Unilateral knee replacement was performed on 56 patients (54.3%) and remaining 47 (45.6%) had simultaneous bilateral TKA. Forty (34.8%) patients were obese, and severe pre-operative deformity (> 15°) was observed in 47 (31.3%) patients. Mean coronal alignment of the knee joint was 91.33° (SD: 90.69° valgus–88.92° varus). The mean post-operative KSS noted in obese and non-obese subjects were 93.43 (84–98) and 94.76 (85–98) respectively. Post-operative KSS for knees with severe deformity was 94.08 (80–98), while it was 95.76 (83–98) in those with mild to moderate deformities.

The study confirms that navigation in CAS–TKA consistently achieved coronal alignment of the knee joint within ± 3°, irrespective of the patient BMI and degree of deformity.