An intra-articular synovial lipoma of the hip, possibly causing osteoarthritis: a case report and review of the literature.

In this report, we present the case of an intra-articular synovial lipoma in a 58-year-old female with a coincident marked unilateral hip osteoarthritis. This patient suffered from right hip pain that developed gradually over 2 years. Physical examination noted decreased range of motion and evidence of impingement. MR and CT images showed an intra-articular fat-intense mass in the hip joint that was excised and confirmed as a synovial lipoma on histology. This case reveals that an intra-articular lipoma of the hip could be accompanied by pain or impingement and followed by hip osteoarthritis even in the absence of trauma.