Object The adult presentation of tethered cord syndrome (TCS) is well recognized but continues to pose significant diagnostic and management challenges. The authors performed a retrospective study of clinical outcomes after neurosurgical intervention in 60 adults with TCS. Methods All patients who underwent detethering surgery for caudal cord tethering at Toronto Western Hospital between August 1993 and 2004 were identified. Their clinical charts, operative records, and follow-up data were reviewed. Detethering procedures were performed in 62 patients (age range 17–72 years) for TCS of various origins. Long-term (mean 41.5 months) follow-up data were obtained in 60 patients. The tethering lesions were tight terminal filum in 29 patients, postrepair myelomeningocele in 15, lipomyelomeningocele/lipoma in nine, split cord malformation in four, and arachnoidal adhesions in three. Fifty-nine patients presented with progressive pain and/or neurological dysfunction. One patient underwent prophylactic sectioning of the terminal filum. Most patients (71%) had bladder dysfunction at presentation. Microsurgical release of the tethered cord was performed in each case while using multimodality intraoperative neurophysiological monitoring. The most common complication was cerebrospinal fluid leakage, which occurred in nine patients and was managed by reinforcement sutures in four patients, temporary external drainage in three, and the placement of a lumboperitoneal shunt in two. Infective complications included superficial wound infection in three patients, meningitis in one, and urinary tract infection in one. One patient who had undergone multiple previous intradural procedures experienced worsened foot weakness postoperatively. Another patient experienced temporary unilateral lower-limb numbness. At follow up, improvement was noted in the majority of patients presenting with back (78%) and leg (83%) pain. Improvement was more likely in patients with preoperative motor weakness than in those with sensory deficits. Overall, neurological status was improved or stabilized in 90% of patients. Subjective improvement in bladder function was noted in 50% of patients with bladder dysfunction at presentation. Conclusions Surgery in adult patients with TCS is safe and effective for improving pain and neurological status in the majority of patients; however, patients who have undergone previous intradural detethering procedures in general fare less well, and considerable judgment is required in their management.

To our knowledge, this is the largest series to date reporting the use of multimodality intraoperative neurophysiologic monitoring in the surgical management of adult tethered cord syndrome. Posterior tibial nerve SSEPs have high specificity, but low sensitivity, for predicting new neurologic deficits. In contrast, continuous EMG showed high sensitivity and low specificity. Evoked EMG accurately identified functional neural tissue. The combined recording of SSEPs in concert with continuous and evoked EMGs may provide a useful adjunct to complex microsurgery for adult tethered cord syndrome.