Transient paralysis associated with epidural steroid injection.

Epidural steroid therapy is a commonly applied "conservative" therapy, but it is not inherently benign. Although arachnoiditis, infection, and meningitis have been reported, acute paraplegia has not been reported as a complication of either caudal or spinal epidural steroid injection. A unique case of transient, profound paralysis after epidural steroid injection is reported here. The procedure was carried out without fluoroscopic control and was complicated by a puncture of the thecal sack. Radiographic studies demonstrated a focal, space-occupying lesion in the spinal canal at the level corresponding to the neurologic deficit, which spontaneously resolved over the next 2-3 h. Surgical decompression was initially considered and then deferred in favor of observation. The patient recovered motor, sensory, and bowel and bladder function over the next 48 h. The period of recovery was consistent with an acute but brief compressive injury and inconsistent with an anesthetic effect. Radiographic studies suggest three possible explanations: (a) inadvertent thecal penetration during injection may have produced an atypical anesthetic block; (b) loculation of the injected fluid may have caused a transient compressive lesion; or (c) intrathecal injection may have produced an iatrogenic arachnoid cyst. Although pathologic confirmation of the cause was not possible, the potential for this alarming complication should be recognized by physicians prescribing epidural steroid therapy. We do not suggest that epidural steroid therapy is the treatment of choice for patients with multiple back operations or that it is efficacious for these patients. Our purpose is to alert surgeons and therapists to a rare but potentially devastating complication and to provide our experience in treating it.