Spinal cord disorder due to spinal epidural abscess secondary to thoracic facet joint septic arthritis-a rare case with a surprising evolution

Abstract

Introduction: Septic arthritis of a facet joint (SAFJ) is a relatively rare medical entity and the lumbar segment is its most frequent location. Although unusual, a spinal epidural abscess (SEA) can occur as a complication of SAFJ and possibly damage the spinal cord.

Case presentation: A 53-year-old woman presented with acute right dorsal pain, fever, loss of sphincters control, and paraparesis without causal factor. Forty-eight hours after the symptoms started, imaging revealed a thoracic posterior epidural collection causing compression of the spinal cord and features suggestive of septic arthritis of right T5-T6 facet joint. She underwent an urgent laminectomy and drainage of the abscess. Both blood and abscess cultures isolated Staphylococcus aureus. A diagnosis of complete paraplegia grade A of the ASIA (American Spinal Injury Association) Impairment Scale (AIS) with neurologic level T10 was made 5 days after surgery. She took 3 months of an intensive rehabilitation program at our Physical and Rehabilitation Medicine ward. With an unexpected favorable evolution, both neurological and functional, she was discharged with an incomplete paraplegia AIS D and functionally independent in all tasks.

Discussion: This case reveals an infrequent medical condition on a rarely affected spinal segment. An early diagnosis and proper treatment of SAFJ and SEA are of major importance to avoid severe related consequences. Patients with spinal cord injury with severe neurological deficits due to these conditions greatly benefit from an interdisciplinary rehabilitation program to improve neuromotor and functional status.

Fig. 1. MRI at the ER.

a Sagittal plane, STIR sequence showing T5-T6 facet joint with small intra-articular effusion and bone edema (arrow); b Sagittal plane, contrast enhanced T1 sequence showing posterior epidural abscess (arrows); c Axial plane, T2 sequence showing spinal cord compression (arrow).

Fig. 2. MRI 20 days after surgery.

a Sagittal plane, STIR sequence showing a small laminae of the posterior spinal epidural abscess (arrows); b Sagittal plane contrast enhanced T1 sequence showing laminectomy changes from T4 to T6.

Fig. 3. MRI 2 months after surgery.

Sagittal plane, contrast enhanced T1 sequence, showing no residual abscess and the presence of hyperintensity signal, corresponding to surgical changes after laminectomy.