Sonography of the iliopsoas tendon and injection of the iliopsoas bursa for diagnosis and management of the painful snapping hip.

OBJECTIVE: The purpose of this study was to compare sonographic evaluations of patients referred with suspected snapping of their iliopsoas tendon with the pain relief achieved from anesthetic injection of the iliopsoas bursa, and with the subsequent surgical outcome. This study also assessed the effectiveness of Kenalog injection into the iliopsoas bursa for long-term pain relief. PATIENTS AND METHODS: Dynamic and static sonography was performed in 40 patients with clinically diagnosed snapping hips. The iliopsoas bursa was injected with Bupivicaine and Lidocaine in the first 22 patients, and an additional 1 ml Kenalog-40 was added to this mixture in the last 18 patients. We compared the static and dynamic sonographic findings with change in the patients' level of pain at 2 days after anesthetic injection. The sonographic findings and response to anesthetic injection were also compared to the response to Kenalog injection and the results of any subsequent surgery.
RESULTS: Static sonography of the iliopsoas tendon was normal in 38 patients, and detected iliopsoas bursitis in one patient and iliopsoas tendinopathy in another. Snapping of the iliopsoas tendon was observed using dynamic sonography in 9 of the 40 patients. Following anesthetic injection of the iliopsoas bursa, 29 patients had complete or partial pain relief, and 11 patients had no pain relief. Eight of the nine patients with a snapping iliopsoas tendon had complete or partial pain relief from the bursal injection. Twelve of the 29 patients with pain relief after anesthetic injection later had an arthroscopic iliopsoas tendon release, and all of these 12 patients had a good postoperative result. Of the 18 patients who had Kenalog-40 injected into the iliopsoas bursa and did not have iliopsoas surgery, 16 had sustained pain relief following the injection.
CONCLUSIONS: Patients with groin pain and a clinically suspected snapping iliopsoas tendon can benefit from injection into the iliopsoas bursa even if the snapping tendon is not visualized sonographically. The use of a corticosteroid may provide long-term pain relief, and pain relief after injection is a predictor of good outcome after surgical release of the iliopsoas tendon.