Physiologic knee joint alignment and orientation can be restored by the minimally invasive double level osteotomy for osteoarthritic knees with severe varus deformity

Purpose

The purpose of this study was to examine early radiological and clinical outcomes following minimally invasive double level osteotomy (DLO) procedure performed for osteoarthritic knees with severe varus deformity.

Methods

Twenty consecutive patients who underwent DLO for varus osteoarthritic knees were included in the study. All patients could be tracked for a minimum of 1 year. Periodical radiological and clinical evaluations were performed at 6 and 12 months after surgery. In the radiological assessment, the following parameters were measured on full-length weight-bearing radiographs both pre- and postoperatively: mechanical tibiofemoral angle (mTFA), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), and joint-line convergence angle (JLCA). In addition, subjective clinical results were evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee (IKDC) Subjective Score.

Results

The mean age of the study population was 62.5 ± 6.8 years (range 45–76 years). In the radiological evaluation, the preoperative mTFA, mLDFA, mMPTA, and JLCA values averaged 13.5° ± 3.1° varus, 91.1° ± 1.4°, 82.3° ± 2.0°, and 5.8° ± 2.3°, respectively. At 6 and 12 months, all of the radiological parameters significantly improved and corrected to the values within normal range. In the clinical assessments at the follow-up evaluations, both the KOOS and IKDC subjective scores significantly improved from the preoperative values. No significant changes were noted between the 6 and 12-month results in the radiological and clinical assessments.

Conclusions

The minimally invasive DLO technique is a valuable surgical technique accomplishing restoration of physiologic knee joint alignment and orientation with significant improvement in patient-registered clinical outcomes in early postoperative evaluation. Although the follow-up period is still short, the excellent clinical and radiological outcomes shown in the present study support the efficacy of this procedure.

Level of evidence

Retrospective case series, Level IV.