Characterization of Orthopaedic Indications Among Patients Undergoing Tethered Cord Release.

Abstract

Background: Tethered cord syndrome (TCS) can present with neurologic, urologic, and/or orthopaedic symptoms, but little research has focused on the orthopaedic conditions that result in tethered cord release (TCR). This study aims to categorize orthopaedic findings associated with TCS and identify which conditions require further surgical intervention post TCR.

Methods: This retrospective cohort study involved 247 patients from our tertiary referral center, all enrolled in the National Spina Bifida Patient Registry (NSBPR) and who underwent TCR between 2007 and 2017. Patients were grouped by tethered cord diagnosis: fatty filum (fatty filum, low-lying cord), lipoma [lipoma, meningocele, myelocystocele, diastematomyelia, meningocele manqué (MM)], and myelomeningocele (MMC). TCR indications were classified as orthopaedic or urologic "yellow" or "red" flags-yellow flags denoting the initial symptoms prompting a referral for tethered cord work-up and red flags representing physician-identified indicators for TCR. Red-flag surgical indicators were identified by an interdisciplinary team of orthopaedic surgeons, urologists, and neurosurgeons. Orthopaedic yellow and red flags included findings such as gait abnormalities or extremity deformities, while urologic flags included hydronephrosis or incontinence. Data on orthopaedic surgeries performed within 18 months post TCR were collected.

Results: Orthopaedic-only symptoms were found in 41 patients (yellow flags) and 51 patients (red flags). Both urologic and orthopaedic symptoms led to TCR in 29 patients (yellow) and 54 patients (red). The number of orthopaedic indicators for TCR was strongly correlated with the total number of orthopaedic surgeries performed within 18 months after TCR (P < .00001). Additionally, the number of orthopaedic yellow flags was significantly correlated with the number of TCRs a patient underwent (P = .002). Among those who went on to require orthopaedic intervention, the most common surgeries performed were foot, ankle, and knee contracture releases.

Conclusions: Formal orthopaedic evaluation is an essential component of the multidisciplinary assessment and treatment of TCS. Nearly half (47%) of TCR patients presented with preoperative orthopaedic indicators, which varied by tethered cord diagnosis. Despite undergoing TCR, 16% of patients required further surgical intervention for definitive management of their orthopaedic conditions.

Key concepts: (1)Orthopaedic symptoms and sequelae are common among patients with tethered cord syndrome (TCS)-many will go on to require surgery.(2)Foot and ankle contractures are among the top presenting orthopaedic manifestations of TCS.(3)Formal orthopaedic evaluation is an essential component of the multidisciplinary assessment and treatment of TCS.(4)Our data suggest a relationship between orthopaedic presenting symptoms and the number of tethered cord release surgeries a patient eventually went on to receive.(5)Longitudinal orthopaedic monitoring is essential for the comprehensive care of patients with TCS.

Level of evidence: Level III.