ASYMMETRY OF BONE MINERAL DENSITY OF THE HIPS IN PATIENTS WITH UNILATERAL KNEE OSTEOARTHRITIS: A CROSS-SECTIONAL STUDY

Background: Osteoarthritis of any joint may exert different effects on bone mineral density that may be the result of several mechanisms including change in the pattern of weight load distribution. In this cross-sectional study we tried to find correlations between unilateral knee osteoarthritis and bone mineral density of hips and lumbar vertebrae. Methods: Forty three patients with knee osteoarthritis (unilateral or more severe in one side) were recruited in this study. The American college of Rheumatology Criteria was followed for the diagnosis of osteoarthritis. Dual X-Ray absorptiometry was used to obtain the T score and the Z score of the hips and lumbar vertebrae. Results: The T score and Z score of the hip and T score of the femoral neck, at the side with ipsilateral knee osteoarthritis was lower than the other side (p < 0.05). The mean Z score and T score of the vertebrae was negative irrespective of the side of osteoarthritis. Conclusions: Bone mineral density of the hip with ipsilateral knee osteoarthritis was lower than the other side, which suggests that BMD may be sensitive to some extent in detecting osteoporosis in these patients; it has also been observed that osteoarthritis might not affect bone mineral density of the hips and lumbar vertebrae in the same manner or to the same extent.