Low Back Pain Caused by Iliopsoas Tendinopathy Treated with Ultrasound-Guided Local Injection of Anesthetic and Steroid: A Retrospective Study

BACKGROUND: Low back pain is a prevalent symptom that occurs in all age of people, whereas the pathogenesis is unknown. Iliopsoas tendinopathy is an increasingly recognized hip disorder that may contribute to low back pain. Our purpose is to evaluate the effect of ultrasound-guided local injection of anesthetic and steroid into the trigger point of iliopsoas tendon in treating low back pain caused by iliopsoas tendinopathy. MATERIALS AND METHODS: This retrospective study reviewed 45 patients diagnosed with iliopsoas tendinopathy treated by B-ultrasound guided injection of 2 mL 2% lidocaine and 1 mL (5 mg) triamcinolone acetonide into the trigger point of iliopsoas tendon from March 2016 to June 2016. Medical records were collected to analyze the clinical presentation. Numerical Rating Scale (NRS) measuring low back pain and Harris Hip score (HHS) measuring hip pain and function were administered to determine patient outcomes. Telephone follow-up was conducted, and the mean follow-up was 11 months. RESULTS: We observed that most patients with iliopsoas tendinopathy also complain about chronic low back pain except for groin pain. After injection of anesthetic and corticosteroid into the iliopsoas tendon, the NRS of patients with low back pain fell from 7.68±1.31 to 2.58±1.16 immediately after the injection and 0.75±0.73 at follow-up. The HHS improved from 43.02±16.81 to 98.15±2.56 at follow-up. Statistically significant difference (P<0.001) was observed. All patients returned to their original level of function, and only five patients presented with mild low back pain at the follow-up. CONCLUSION: Low back pain is a prevalent presentation for iliopsoas tendinopathy. Diagnosis of iliopsoas tendinopathy should be considered in patients with low back pain with tenderness over the iliopsoas tendon. Ultrasound-guided local injection of anesthetic and steroid lead to satisfactory effect in relieving low back and groin pain and improving joint function.