Permanent Paraplegia as a Complication of Injection of Contrast Media at L2-L3 Vertebral Level

BACKGROUND: The lumbar intrathecal (subarachnoid) space is accessed for both therapeutic and diagnostic purposes. Occasionally, the needle may unintentionally enter the intrathecal space during lumbar interlaminar epidural steroid injections (LESIs)-one of the most commonly performed medical procedures in the United States. Ordinarily, this merely constitutes a minor complication or even a desired placement (in the case of some diagnostic procedures). However, some patients have a rare condition wherein the spinal cord terminates below the L2 vertebral level (tethered cord). In such cases, injections administered at the lumbar level may potentially result in spinal cord damage and irreversible paraplegia if the physician performing the intervention does not recognize the intramedullary position of the needle. OBJECTIVE: The aim of this study is to describe and analyze an unintentional L2-L3 injection of contrast medium into a tethered spinal cord. Many physicians may consider lumbar injections "safe" because the spinal cord usually terminates at or above the L2 vertebral level. However, complacency stemming from this false impression of safety contributes to nonadherence to practice guidelines, which may lead to catastrophic neurological complications. Presented here is the first published occurrence of paraplegia that resulted from contrast medium injection into the spinal cord during a myelography study performed below the L2 vertebral level. CONCLUSIONS: Disregard of the procedural guidelines by the physicians performing an elective diagnostic intervention may cause devastating neurological complications. The described casualty occurred because of failure to review previous imaging studies, injection of the contrast medium despite unsuccessful attempts to aspirate cerebrospinal fluid, and an unwillingness to terminate the procedure immediately when the patient reported an unusual sensation in both of his lower extremities. Consequently, we suggest that not only for cervical and thoracic but also for lumbar interlaminar ESIs, previous imaging studies should be reviewed before the injection.