Pyomyositis of the iliacus muscle and pyogenic sacroiliitis after sacroiliac joint block -A case report-

Abstract

Sacroiliac joint block can be performed for the diagnosis and treatment of sacroiliac joint dysfunction. Although sacroiliac joint block is a common procedure, complications have not been reported in detail. We report a case of iliacus pyomyositis and sacroiliac joint infection following a sacroiliac joint block. A 70-year-old female patient received sacroiliac joint blocks to relieve pelvic pain. The patient was admitted to the emergency room two days after the final sacroiliac joint block (SIJB) with the chief complaints of left pelvic pain corresponding to a visual analogue scale (VAS) score of 9 and fever. A pelvic MRI indicated a diagnosis of myositis. After 1 month of continuous antibiotic therapy, the patient's erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level remained elevated. A (67)Ga SPECT/CT was done. Abnormal uptake was seen at the left sacroiliac joint (SIJ), and septic sacroiliitis was suspected. The CRP normalized to 0.29 mg/dl and the ESR decreased to 60 mm/hr, and the patient had no fever after 57 days of antibiotic therapy. She was directed for follow up at an outpatient clinic.

Keywords: Iliacus; Infection; Pyomyositis; Sacroiliac.

Fig. 1

This is an MRI scan of the pelvic area, showing an axial T2-weighted image (A) and coronal T2-weighted image (B). Diffuse thickening and increased signal intensity are seen in the left iliacus muscle.

Fig. 2

This is an image from the ⁶⁷Ga SPECT/CT scan of the pelvic area, showing the axial view. An abnormal uptake of Gallium was observed in the left gluteal muscle and left SIJ, with bony erosion impression.