structures communicating with the joint capsule included iliopsoas bursae ( 13 cases ) , bursae associated with the greater trochanter ( 21 cases ) , ischiotrochanteric bursae created by abnormal articulation between the ischium and lesser trochanter ( two cases ) , and abscess cavities not associated with a bursa ( four cases ) .
C0022417
articulation
C0006441
bursa