Abstract
Introduction: Obtaining accurate anatomic and mechanical alignment in total knee arthroplasty (TKA) is correlated with improved long-term results. Whether computer-assisted total knee arthroplasty (CAS-TKA) more reliably produces a neutral mechanical and anatomic alignment and improves functional outcomes over traditional total knee arthroplasty (T-TKA) remains debatable. This report evaluates the results of CAS-TKA vs. T-TKA in a series of patients who underwent bilateral TKA performed at the same surgical operation.
Methods: Sequential bilateral TKA were performed on 36 patients utilizing CAS-TKA in one knee and T-TKA in the contralateral knee by two high volume, fellowship trained surgeons. A review and statistical analysis of prospectively collected data was performed after a mean follow-up of 2.2 years.
Results: Knee Society Scores (KSS) improved from 42.9 to 96.3 in the CASTKA group vs. 46.0 to 94.8 in the T-TKA group. Range of motion (ROM) improved from 116.8° to 126.9° in the CAS-TKA group vs. 118.3° to 125.4° in the T-TKA group.
With numbers available, there were no differences between the groups with regard to change in KSS (p=0.38), ROM (p=0.42), mean postoperative anatomic alignment (5.78° vs. 5.50°, p=0.37), femoral angle (5.56° vs. 5.61°, p=0.84), or tibial angle (89.89° vs.
89.69°, p=0.46). There was a non-significant trend towards fewer outliers in the CASTKA group with respect to anatomic alignment (2.8% vs. 13.9%, p=0.09) and tibial angle (0% vs. 5.6%, p=0.46).
Conclusion: There is not an apparent benefit to the use of CAS-TKA with regards to KSS, ROM, or alignment in the hands of high-volume, fellowship-trained total joint specialists. The clinical relevance of the non-sig-nificant trend towards fewer outliers in the CAS-TKA group is unknown at the current follow-up interval. These results may not preclude the benefits of CAS-TKA in lower-volume or less experienced TKA surgeons.
Correspondence should be addressed to Diane Przepiorski at ISTA, PO Box 6564, Auburn, CA 95604, USA. Phone: +1 916-454-9884; Fax: +1 916-454-9882; E-mail: ista@pacbell.net