Treatment of Iliopsoas Tendinitis after a Left Total Hip Arthroplasty with Botulinum Toxin Type A

Abstract

Objective: Treatment of iliopsoas tendinitis after a left total hip arthroplasty with botulinum toxin type A (BTX-A). Design: Case study. Setting: Outpatient musculoskeletal clinic. Participants: Single patient subject with left iliopsoas tendinitis after a left total hip arthroplasty. Interventions: Fluoroscopically guided injection of 100 units of BTX-A into the left iliopsoas muscle. Main Outcome Measures: Functional improvement with Oswestry Disability Index (ODI) and scores using a 0–10 point pain intensity numerical rating scale (PI-NRS) at one and 6 months follow up. Results: A 71-year-old female with 4 months of left groin pain after successful total hip arthroplasty. Work up did not reveal any infection or malpositioning of the left hip prosthetic components. Attempts at aspiration revealed no fluid in the joint space. A positive xylocaine muscle block confirmed a diagnosis of iliopsoas tendinitis. The BTX-A injection resulted in an improved left groin pain rating from a baseline of 7 to 1 and improved ability to flex her left hip at one month follow up. Pain was rated 8 at six months follow up. ODI improved from a baseline of 26% to 22% at one month follow up and 18% at 6 months follow up. Conclusions: Iliopsoas tendinitis is an uncommon cause of groin pain but has been described after a total hip arthroplasty in several case reports. Non-operative management has not been well established but includes anesthetic and corticosteroid injection into the muscle. The use of botulinum toxin A provided significant pain relief, functional improvement, and may represent an alternative to the surgical management of iliopsoas tendinitis. Key words: Rehabilitation, iliopsoas tendinitis, iliopsoas bursitis, total hip arthroplasty, groin pain, botulinum toxin.