Prevalence study of iliopsoas bursitis in a cohort of 860 patients affected by symptomatic hip osteoarthritis.

We used ultrasound to evaluate iliopsoas bursitis (IB) prevalence in 860 patients (568 males, 292 females, 62 ± 7 years) suffering from symptomatic Kellgren-Lawrence grade II-III-IV hip osteoarthritis. Lequesne index and visual analogue scale (VAS) were recorded. Anterior hip was scanned and images recorded. Maximum IB diameter was measured and drained (volume recorded). Two radiologists evaluated the presence of IB, joint effusion, synovial hypertrophy, communication between bursa and articular space. IB was found in 19/860 (2.2%) patients (16 males, 3 females, 65 ± 11 years; grade II osteoarthritis = 4; III = 9; IV = 6). Mean bursa diameter = 2.9 ± 0.9 cm, volume = 35 ± 34 mL. Effusion was present in 9/19 patients, hypertrophy in 6/19 and communication in 9/19. In patients with no IB, effusion was detected in 27/860 and hypertrophy in 25/860 (p < 0.001 compared with IB patients). κ = 1 for all. VAS index and Lequesne index were not significantly different between patients with or without IB (p ≥ 0.468). Ultrasound can detect associate findings in grade II-IV hip osteoarthritis patients with high reproducibility.