Open-Wedge High Tibial Osteotomy and Combined Abrasion/Microfracture in Severe Medial Osteoarthritis and Varus Malalignment: 5-Year Results and Arthroscopic Findings After 2 Years

PurposeTo determine survivorship and functional results of medial open-wedge high tibial osteotomy (HTO) combined with a chondral resurfacing procedure (abrasion/microfracture) in patients with Kellgren-Lawrence grade 3 and 4 osteoarthritis with full-thickness cartilage defects and varus malalignment.MethodsFrom September 2005 to December 2008, all cases of HTO (fixation with an angular-stable internal fixator) combined with a chondral resurfacing procedure performed at our institution were prospectively surveyed, with a minimum follow-up of 5 years, regarding survival (not requiring arthroplasty), functional outcome (subjective International Knee Documentation Committee [IKDC] score), and subjective satisfaction (whether patients would undergo the operation again). Clinical evaluation (according to objective IKDC parameters), radiologic evaluation, and revision arthroscopy for evaluation of regenerated cartilage were performed between 1 and 2 years.ResultsA total of 91 knees (85 patients; mean age, 50.4 ± 8.0 years; age range, 28.3 to 67.7 years) were included. The survival rate was 95.2% (95% confidence interval, 90.7% to 99.7%) at 5 years, with 4 conversions to arthroplasty (3 unicondylar and 1 total knee arthroplasty; follow-up rate, 87.9%). Subjective IKDC scores significantly improved from 45.1 ± 11.6 points preoperatively to 69.1 ± 14.2 points after 1 year, 66.4 ± 14.5 points after 3 years, and 67.2 ± 14.4 points after 5 years (P < .001). In 94.9% of the cases patients were satisfied with the result after 5 years, including those with arthroplasty. Revision arthroscopy was performed in 80 cases (87.9%) at 1.5 ± 0.8 years: Cartilage regeneration was graded good in 50.0% and excellent in 25.8% on the tibial side compared with 48.1% and 39.0%, respectively, on the femoral side (P < .001). The overall complication rate was 6.6%.ConclusionsHTO in combination with a chondral resurfacing procedure is effective in the treatment of severe medial osteoarthritis and varus malalignment. The effect of the chondral resurfacing in this combined approach remains unclear.Level of EvidenceLevel IV, therapeutic case series.