Aim: To evaluate results of fully congruent Mobile bearing knee arthroplasty for valgus arthritic knees using lateral capsular approach and realignment of vastus lateralis.

Material and Method: We reviewed results of 50 mobile bearing total knee arthroplasties performed consecutively between 2001 and 2006 for Valgus arthritic knees, using lateral capsular approach and realignment of vastus lateralis. Patients were evaluated using oxford and International knee society Score. Radiographs were examined for alignment of the component, evidence of loosening and scanograms assessed to evaluate the restoration of mechanical axis.

Results: The study group consisted of 47 patients, 20 men and 27 women who received fifty knees. The mean age at the primary operation was 71.57 years (range 47–82 years; SD, 9.5). The mean follow up was 4.2 years (range 1–6 years; SD, 1.35). The mean Valgus deformity was 15.92° (rang from 15–20 SD 1.89). Fixed flexion deformity was seen in 15 knees.

The mean Oxford Knee Society ratings was 52 (range 47–55; SD, 3.18) preoperatively, and 19 (range 14–24; SD, 3.72) at final follow up. The pre op mean range motion was 84.28° (range 45°–120°; SD 21.73). At final follow up the average range of motion was 107.5° (range 95°–120°; SD 8.93). According to the system of the Knee Society, the average knee score was 94 points and the average functional score was 89 points at final follow up.

There were no clinical failures or cases of postoperative instability and no cases of radiographic loosening or wear.

Radiological evaluation: None of these knees had radiographic evidence of loosening or osteolysis. Mechanical axis was restored in all the patients.

Conclusion: This study demonstrates satisfactory results of Mobile bearing knee arthroplasty using lateral parapatellar with proximal realignment of vastus lateralis for Valgus arthritic knees.