Surgery in adult onset tethered cord syndrome (ATCS): review of literature on occasion of an exceptional case

Tethered cord syndrome, usually discovered in childhood, is a developmental abnormality impairing the longitudinal movement of the spinal cord that can be combined with various forms of spinal dysraphism. Adult onset tethered cord syndrome (ATCS) seems not as rare as once thought, however, low susceptibility in adulthood commonly leads to a delay in diagnosis and therapy. We conducted a meticulous literature research to evaluate the clinical presentation, associated malformations, prognostic factors, as well as the benefits and risks of surgical treatment in ATCS patients. The age of patients at onset of symptoms ranged from 18 to 76 years with a mean of 36.5 years, including 184 males and 202 females. In contrast to the pediatric clientele, pain is the predominant symptom in adults, and elicitating mechanisms like trauma, excessive physical training, or degenerative spinal canal stenosis are reported more often. Surgical untethering aims the restoration of craniocaudal mobility of the spinal cord in order to prevent the further progression of symptoms, to restore neurological function, and to improve pain. In our evaluation of literature, pain was the most responsive symptom after surgical untethering (307 of 368 patients). Sensory and motor symptoms also seem to benefit from the surgery, especially if less than 6 months standing and mild. Improvement could be achieved in 43% (144 of 335 patients) for sensory deficits and 58.6% (191 of 326 patients) for motor deficits. Sphincter troubles are less responsive; they show an improvement in 45.6% (141 of 309 patients). Factors reported to be associated with the postoperative deterioration and/or bad outcome are the split cord malformation, lipomyelomeningocele, previous surgery, rapid motor function worsening experienced shortly before the operation, and long delay in diagnosis. The rate of secondary decline and retethering could not be established in our literature research. We report on an additional case of ATCS with the late onset of symptoms at the age of 49; she underwent surgical untethering with neuronavigational guidance. Performing neuronavigational guidance on the basis of multimodal images (computed tomography and magnetic resonance imaging fused with the intraoperative biplanar X-ray) in our patient showed substantial benefit in the surgical orientation within a complex skeletal and neuronal anomaly.