Symptomatic synovial herniation pit-MRI appearances pre and post treatment.

Herniation pits are small benign lucent oval lesions within the anterior aspect of the superolateral femoral neck and were first described in 1982 by Michael J. Pitt. They are widely believed to occur as a result of mechanical forces from the overlying capsule resulting in herniation of soft tissues and synovium through a small bony defect. More recently, there has been evidence to suggest that femeroacetabular impingement may have a role in their aetiology. We present a case of a 59-year-old male patient who developed hip pain following a jump from a wall. MRI was performed following failure of conservative management and demonstrated a small herniation pit with surrounding bone oedema. Following flouroscopic intra-articular steroid injection there was complete resolution of the patient's symptoms and the bone oedema surrounding the herniation pit. We review the potential causes, imaging appearances and potential treatment of synovial herniation pits with an emphasis on the role of radiologically guided intra-articular steroid injection.