Iliopsoas Tendonitis Following Total Hip Arthroplasty: How effective are selective steroid injections in treating this uncommon cause of groin pain?

Impingement of the iliopsoas tendon is an uncommon cause of groin pain following total hip arthroplasty (THA). Clinical diagnosis and treatment options are varied in the literature. The purpose of this study was to determine the effectiveness of fluoroscopically assisted iliopsoas bursa injections in patients with iliopsoas tendonitis following THA. We retrospectively reviewed 19 patients who underwent THA at our institution and were later diagnosed with iliopsoas tendinitis. All patients had persistent groin pain after THA, which was triggered by active hip flexion, hip flexion against resistance, and passive hyperextension of the hip. No patient had radiographic evidence of component failure, and all patients had laboratory evaluations which were negative for occult infection. All 19 patients were referred to a single interventional radiologist for fluoroscopic injection of the iliopsoas bursa with a local anesthetic and corticosteroid. Prior to injection, each patient filled out a pain assessment questionnaire indicating the location and severity of pain, which was reviewed by the radiologist before and after the procedure. A telephone questionnaire was administered to determine patient’s functional status following the injection. The average modified HHS improved from 61.2 pre-injection to 82.3 post-injection (p<0.001), but nine patients (47%) required a second injection at an average of 8.9 months after the first injection. Ultimately 6 patients (31.6%) had to undergo an additional surgical procedure to address the underlying cause of the iliopsoas irritation. Iliopsoas tendonitis is uncommon following THA but is a condition that should be considered in the differential diagnosis of all patients who present with groin pain after total hip arthroplasty. Fluoroscopic injection of the iliopsoas bursa can give good pain relief and may require more than one injection; but it should be considered part of the non-operative treatment plan before surgical release of the iliopsoas tendon or component revision.