Quantitative T2 mapping of femoral head cartilage in systemic lupus erythematosus patients with noncollapsed osteonecrosis of the femoral head associated with corticosteroid therapy.

PURPOSE: To evaluate articular cartilage degeneration with transverse relaxation time (T2) mapping in systemic lupus erythematosus (SLE) patients with noncollapsed and asymptomatic osteonecrosis of the femoral head associated with corticosteroids.

MATERIALS AND

METHODS

T2 mapping with a 1.5-T magnetic resonance imaging system was prospectively performed for 28 normal hips from 14 healthy volunteers (control group) and 15 hips from 10 SLE patients that met the inclusion criteria of noncollapsed and asymptomatic osteonecrosis of the femoral head (osteonecrosis group). Exclusion criteria were past experience of pain, trauma, infection, or prior hip joint surgery. Distribution of T2 values of the femoral head cartilage were compared between the control group and the osteonecrosis group with respect to acetabular dysplasia by center-edge angle (CEA).

RESULTS

T2 values of the femoral head cartilage were significantly higher in the osteonecrosis group than in the control group (34.4 msec vs. 30.8 msec, P = 0.001). Multiple regression analysis revealed that the osteonecrosis group and decreased CEA was significantly associated with high T2 values (T2 value = 34.6 + 3.6 × [osteonecrosis] - 0.14 × CEA, R(2) = 0.52, P = 0.003).

CONCLUSION

Degeneration of articular cartilage was associated with osteonecrosis of the femoral head in SLE patients and acetabular dysplasia.