Abstract
BackgroundHigh tibial medial open-wedge valgus osteotomy (HTO) is a well-established procedure for unicompartimental medial osteoarthritis of the young and active patient. The aim of this study was to evaluate the influence of asymptomatic mild to moderate cartilage lesions of the lateral tibiofemoral compartment on the clinical outcome after HTO. MethodsFrom 2005 to 2012 a total of 63 patients underwent HTO for medial osteoarthritis of the knee at a single university orthopaedic center. Baseline data as well as intraoperative findings including the grade and location of cartilage lesions were evaluated retrospectively. Two groups were formed regarding the integrity of the lateral tibiofemoral compartment as measured by the Outerbridge score (group A: no lateral cartilage defects, group B: mild to moderate lateral cartilage defects). Functional outcome was assessed using the Knee and Osteoarthritis Outcome Score (KOOS) including its five subscores. ResultsComparing pre- and postoperative data, we identified an overall benefit of the HTO procedure as measured by the KOOS. Group A (no lateral cartilage defects) showed an increase in all five KOOS subscores (p=0.00 – 0.01), whereas for group B (mild to moderate lateral cartilage defects) only two KOOS subscores revealed a significant increase (p=0.03 – 0.04). There was also a statistically significant difference of the total KOOS score with higher values for group A at the postoperative visit. Cartilage defects with a higher Outerbridge score were associated with lower postoperative KOOS subscores. ConclusionsMild to moderate cartilage defects of the lateral compartment humble the total outcome after HTO procedure. Thus, indication for HTO should be made very carefully, if any degree of lateral cartilage degeneration is present.
Focal Cartilage Defects of the Lateral Compartment do Influence the Outcome After High Tibial Valgus Osteotomy
