Osteochondritis dissecans (OCD) is a disorder of subchondral bone that causes adverse effects on the overlying cartilage and commonly affects the knee. The incidence of OCD and its long-term effect on the knee joint are controversial. Hypothesis/Purpose: The purpose of this study was to (1) evaluate the rate of
osteoarthritis and
knee arthroplasty in a population-based cohort of patients with OCD lesions treated operatively and (2) evaluate factors that may predispose patients to
knee osteoarthritis and
arthroplasty. The investigators hypothesized that OCD lesions diagnosed after skeletal maturity and treatment with fragment excision would be predictive of a diagnosis of
osteoarthritis.
STUDY DESIGN: Cohort study; Level of evidence, 3.
METHODS: The investigators identified 221 patients (mean ± SD age, 26.1 ± 13.6 years) with OCD lesions treated operatively between 1976 and 2010 and followed for 16.3 ± 11.4 years (mean ± SD) from diagnosis. Information related to the diagnosis, laterality of lesion, details of treatment, and progression to
osteoarthritis was obtained from the medical record. Surgical treatment was classified as fragment excision, fragment preservation (lesion drilling and/or fragment fixation), or chondral defect grafting (osteochondral allograft or autograft). Factors predictive of
osteoarthritis and
arthroplasty were examined.
RESULTS: There were 134 patients in the fragment excision group, 78 patients in the fragment preservation group, and 9 patients in the chondral defect grafting group. In the fragment excision group, the cumulative incidence of
osteoarthritis was 12.0% at 5 years, 17.0%
at 10 years, 26.0% at 15 years, 39.0% at 20 years, and 70% at 30 years. The cumulative incidence of
arthroplasty was 2.0% at 5 years, 4.0%
at 10 years, 4.0% at 15 years, 10.0% at 20 years, and 32.0% at 30 years. In the fragment preservation group, the cumulative incidence of
osteoarthritis was 3.0% at 5 years, 7.0%
at 10 years, 16.0% at 15 years, 25.0% at 20 years, and 51% at 30 years. The cumulative incidence of
arthroplasty was 0.0% at 5 years, 0.0%
at 10 years, 3.0% at 15 years, 6.0% at 20 years, and 11.0% at 30 years. No patients in the chondral defect grafting group developed
osteoarthritis or underwent
arthroplasty. Body mass index (BMI) greater than 25 kg/m2 (hazard ratio [HR] 3.3; 95% CI, 1.6-7.0), older age at diagnosis (HR 4.9; 95% CI, 1.8-17.3), and fragment excision (HR 2.3; 95% CI, 1.2-4.6) were predictive of
osteoarthritis.
CONCLUSION: OCD patients treated with fragment excision have a high rate of
osteoarthritis and
knee arthroplasty at long-term follow-up. In contrast, patients treated with fragment preservation or chondral defect grafting have lower rates of
osteoarthritis and
arthroplasty. BMI greater than 25 kg/m2, older age at diagnosis, and fragment excision were predictive of
osteoarthritis.