Minimally invasive approach for drainage of a sacral epidural abscess. A case report and technical note

Sacral epidural abscesses are rare infections, often managed with open surgery, especially in the presence of acute neurological symptoms. We report a novel approach for minimally invasive drainage of sacral epidural abscesses. A 51-year-old man presented to the emergency department complaining of low back pain, generalized muscle pain, pain across several large joints, low-grade fever, and weakness of both legs for ten days. MRI of the patient's lumbosacral spine showed osteomyelitis involving his L5, S1 vertebrae, L5-S1 discitis, as well as anterior and posterior epidural abscesses extending from L5-S1 disc space to the S2 vertebral level. Under CT fluoroscopic guidance a 20-gauge spinal needle was inserted into the sacral hiatus, parallel to the pelvic surface of the sacral canal, and directed cranially. A 0.18- gauge microwire was then advanced through the 20-gauge needle. The 20-gauge needle was exchanged over the guidewire for an 18-gauge blunt tipped needle which was curved to approximate the contours of the sacral canal. The curved needle was inserted through the sacral hiatus with its concavity initially facing upwards, and then rotated 180 degrees to gain access to epidural abscess. Once anatomic access was established 5cc of thick purulent material was evacuated. The patient tolerated the procedure well, and no focal nerve root symptoms were noted following the procedure. Image guided aspiration of sacral epidural abscesses can be carried out in a safe and effective manner using CT fluoroscopy. Aspiration of these abscesses combined with intravenous antibiotics may be an alternative to open surgery in select patients.