Vertebral osteomyelitis: a potentially catastrophic outcome after lumbar epidural steroid injection.

BACKGROUND AND OBJECTIVE Epidural steroid injections are commonly used to palliate the symptoms of spinal stenosis. Deep tissue infection is a known potential complication of these injections. There have been no previous published cases of osteomyelitis without epidural abscess after such injections. We present a case in an elderly patient who presented only with persistent axial low back pain following a lumbar epidural steroid injection (LESI). We emphasize early patient evaluation, consideration of infectious predisposing factors, sterile technique, and skin disinfectant. DESIGN Open-label case report. CASE DESCRIPTION A 77-year-old diabetic male with a history of radicular pain related to lumbar spinal stenosis was treated successfully several years prior with a series of lumbar epidural steroid injections (LESI) and was re-treated with LESIs for recurrent symptoms. Following his second epidural injection, he presented with back pain and induration at the injection site without fever or neurological deficits. Urgent magnetic resonance imaging (MRI) revealed a soft tissue abscess extending close to the epidural space around the corresponding L4/L5 vertebral level. The patient recovered after incision and drainage of the abscess which was associated with an osteomyelitis of the L4 and L5 vertebral spine. The causative organism was methicillin-resistant Staphylococcus Aureus. CONCLUSION This case demonstrates that even with proper aseptic techniques, immune-compromised patients who are colonized with an aggressive micro-organism may develop a potentially catastrophic infectious complication if subtle persistent symptomatic complaints are not promptly and carefully evaluated.