Is It Possible to Correct Congenital Spinal Deformity Associated With a Tethered Cord Without Prophylactic Intradural Detethering?

Abstract

Background Patients who have a congenital spinal deformity with a tethered cord generally are treated with prophylactic intradural detethering before deformity correction. However, the detethering procedure carries substantial risk, and it is not clear whether deformity correction can be performed without detethering. Questions/purposes To determine the (1) correction rate, (2) proportion of patients who experienced complications after surgery, and (3) neurological status after recovery from surgery in a group of patients with congenital spinal deformity and a tethered cord who were treated either with posterior spinal fusion only (PSF), pedicle-subtraction osteotomy (PSO), or a vertebral column resection (VCR), based on an algorithmic approach. Methods Between 2006 and 2016, we treated 50 patients surgically for a congenital spinal deformity and a tethered cord. We defined a congenital spinal deformity as one that was caused by failure of vertebral segmentation, failure of vertebral formation, or both, and we made the diagnosis of a tethered cord based on a conus medullaris lower than L2 level, or a diameter of the filum terminale greater than 2 mm, as shown on magnetic resonance image. Of those, nine patients were lost to followup before the 2-year minimum, leaving 41 for analysis at a mean followup of Each author certifies that neither he or she, nor any member of his or her immediate family, has funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. Clinical Orthopaedics and Related Research® neither advocates nor endorses the use of any treatment, drug, or device. Readers are encouraged to always seek additional information, including FDA approval status, of any drug or device before clinical use. Each author certifies that his or her institution approved the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research.

CORR Insights®: Is It Possible to Correct Congenital Spinal Deformity Associated With a Tethered Cord Without Prophylactic Intradural Detethering?

“…In the current study, Tao and colleagues [3] have shown that, in carefully selected patients, scoliosis correction can be surgically obtained without incurring neurologic injury even in the absence of detethering prior to correction. Their series of 41 patients without permanent neurologic injury does not however, prove that scoliosis correction without detethering is "safe."…”

Surgical correction of pediatric spinal deformities with coexisting intraspinal pathology: A case report and literature review

“…[ 2 , 4 , 5 , 26 ] An additional nine articles were included, describing spinal deformity correction in patients with congenital scoliosis with intraspinal pathology, such as diastematomyelia, tethered cord, and syringomyelia with or without Chiari malformation [ Table 3 ]. [ 1 , 3 , 8 , 11 , 19 - 21 , 23 , 27 ]…”

“…Nine articles described the use of osteotomies or posterior vertebral column resection to correct kyphoscoliotic deformities without lengthening the spinal column. [ 1 , 2 , 8 , 11 , 19 , 20 , 23 , 26 , 27 ] Of all the articles reviewed, seven described the use of compressive forces on the convex side of the deformity as the primary mode of correction. [ 5 , 12 , 27 ]…”

“…[ 2 , 20 , 21 , 27 ] Changes in neuromonitoring signals were reported in three patients during intraoperative corrective maneuvers, but did not result in permanent neurologic sequelae. [ 2 , 21 ] Neurologic complications were reported in six patients (of 203 patients reported total; 2.9%) – three were transient not requiring further intervention,[ 1 , 19 , 26 ] while two had permanent new motor deficits,[ 3 , 8 ] and one whose deficits resolved only after reoperation and revision of instrumentation. [ 1 ]…”

Is it safe and effective to correct congenital scoliosis associated with multiple intraspinal anomalies without preliminary neurosurgical intervention?

“…[ 17 ] Tao et al reviewed 41 patients with congenital spinal deformity and tethered cord and concluded that it was possible to correct congenital spinal deformity associated with tethered cord without prophylactic intradural detethering. [ 18 ] Nonetheless, according to the literature, only 1 or 2 specific intraspinal anomalies are typically assessed. Theoretically, concurrent multiple intraspinal anomalies (coexistence of 3 or more intraspinal anomalies including syringomyelia, split cord malformation [SCM], tethered cord, low conus, intraspinal mass, Chiari malformation or/and arachnoid cyst) can increase the risk of neurologic injury during surgical correction in CS patients compared with the normal intraspinal condition or CS patients with 1 or 2 intraspinal anomalies due to the presence of more complex intraspinal pathologies.…”