Total knee arthroplasty is a well-established procedure in the management of terminal stage arthritis. Among the techniques (posterior-stabilized vs posterior cruciate retaining total knee arthroplasty) it is unclear whether one design has superior outcome over another. The purpose of the present study was to directly compare clinical and radiological outcomes of these two designs.
Methods: A prospective study involving 29 patients who received a cruciate-retaining implant were compared to 30 patients who received posterior-stabilized prosthesis. The patients were followed up at 3 monthly intervals in the first year and 6 monthly thereafter. At 2years follow-up time clinical and radiological evaluation done and results were analyzed.
Results: At 2 years follow-up time mean knee society scores improved from 47.19/34.2 (clinical/functional score) points to 91.9/89.25 points in the cruciate-retaining group and from 46.2/37.5 (clinical/functional score) points to 93.4/92.2 points in the posterior-stabilized group. The ranges of motion were 120.2° (range, 90° to 130°) and 125.3° (range, 100° to 140°) in the cruciate-retaining and posterior-stabilized group respectively, at 2-year follow-up. One had superficial infection (treated with dressing) and one patient with superficial infection required debridement.
Conclusions: This study did not conclusively demonstrate the superiority of one knee design over the other, but clinical and functional score and range of motion were marginally better in patients with posterior stabilized implants which were not statistically significant.