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

Abstract

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.

Pathophysiology of adult tethered cord syndrome: review of the literature

“…2,15,18 This theory is consistent with the experimental data summarized above. Thus, adults who are found to have TCS likely have always had a tethered spinal cord that has not been under significant tension.…”

“…This also would explain why adults with TCS often present after a precipitating event. 1,2,6,8,15 If the adult tethered cord is under just enough tension to not cause symptoms, any movement or lengthening of the spinal canal that would place slightly more traction on the already tethered cord may exceed the amount of tension that blood flow may overcome, thus producing hypoxia and symptoms. Thus, the patient with a tethered cord with only slight tension on the filum would be thrown over the "threshold" level of tension to reduce blood flow and cause symptoms if there was a precipitating event such as an acute disc herniation, for example.…”

“…1,6,9,10,15 Unlike children, adult symptomatology is slightly different, with pain being the most common presenting symptom (rare in children 4 ), and this is followed by sensory disturbances, motor dysfunction and weakness, and urinary dysfunction. 1,2,13,15,18,20 Similar to the pediatric population, surgical intervention to release the adult tethered cord has proven to be successful in preventing further deterioration as well as sometimes improving symptoms and deficits. Thus, cord release has increasingly been accepted as a necessary intervention in symptomatic patients.…”

“…Thus, cord release has increasingly been accepted as a necessary intervention in symptomatic patients. 2,6,9,10,15 The question as to what causes neurological dysfunction in patients with TCS has long been only theorized. Over the last 2 decades, there have been multiple advances in the understanding of the basic science and pathology behind the tethered spinal cord in animal models and in humans.…”

Tethered cord syndrome: a review of the literature from embryology to adult presentation

“…As a result they may receive physical therapy, traditional conservative measures, or surgical management based on degenerative processes, and TCS may not be addressed as the primary or a related cause of the symptoms due to the subtle, nonspecific findings of TCS as well as deficits that do not correlate with specific myotomal or dermatomal patterns. 2 Little data exists about the natural history of adult TCS. 20,22,23,31 Generally, the treatment of such patients is extrapolated from data regarding children with TCS.…”