Iliopsoas injury: an MRI study of patterns and prevalence correlated with clinical findings

Objectives The objective was to retrospectively determine the prevalence and patterns of iliopsoas injuries based on consecutive MRI examinations, correlated with clinical findings. Materials and methods From 4,862 consecutive MRI examinations of the hips and pelvis, 32 patients with 33 iliopsoas injuries were identified and graded as muscle strain, partial tendon tear, and complete tendon tears. These patients' medical records were reviewed to determine age, gender, and cause of symptoms. Results The prevalence of iliopsoas tendon and myotendinous injuries was 0.66% (95% CI: 0.44-0.89). There were 18 females and 14 males whose ages ranged from 7 to 95 years (mean, 54 years). The most frequent presenting symptom was hip pain and the most frequent clinical diagnosis, an occult fracture. The most common injuries in patients under 65 years (16 patients) were muscle strains and partial tendon tears, most often due to an athletic injury. The most common injury in patients 65 years and older (16 patients) was a complete tear (8 patients, all females), 2 of which were spontaneous in origin. Conclusions Each grade of iliopsoas injury occurred with similar frequency. The more advanced the age of the patient, the more severe the injury. Non-athletic injuries predominated in patients 65 years and older; athletic injuries were the most common cause of iliopsoas injury in patients under 65 years.