Central osteophytes in the knee: Prevalence and association with cartilagedefects on MR imaging

OBJECTIVE. The objective of this study was to determine the prevalence and location of central osteophytes in patients referred for MR imaging of the knee and the relationship of central osteophytes to articular cartilage def ects, marginal osteophytes. meniscal tears, and anterior cruciate ligament tears as seen on MR imaging. MATERIALS AND METHODS. Two hundred consecutive patients referred for MR ima ging of the knee were evaluated for central osteophytes, articular cartilag e defects, marginal osteophytes, meniscal tears, and anterior cruciate liga ment tears. A 1.5-T scanner was used, and assessments were made by consensu s of two experienced musculoskeletal radiologists. Seven patients were excl uded, leaving 193 patients in the study population, RESULTS. The prevalence of central osteophytes in the knee was 15% (35 cent ral osteophytes in 29 patients). Patients with central osteophytes were old er (mean age, 52 years versus 38 years), weighed more (mean weight, 204 Ib [92 kg] versus 174 Ib [78 kg]), had more articular cartilage defects (mean, 4.3 versus 1.3), and had more marginal osteophytes (mean, 3.9 versus 1.1) t han patients without central osteophytes (p < 0.0001, Student's t test). Pa tients with central osteophytes were more likely to have a meniscal tear (p = 0.004. chi-square test), but they were not more likely to have an anteri or cruciate ligament tear. All central osteophytes were associated with art icular cartilage defects at the same location. which were full or near-full thickness on MR imaging for 32 of 35 central osteophytes. CONCLUSION. Central osteophytes are common in patients referred for MR imag ing of the knee. When central osteophytes are seen in the knee there is a h igh likelihood of an associated full thickness or near-full thickness artic ular cartilage defect.