Investigation of Surgical Sectioning of the Filum Terminale in Treating Occult Tethered Cord Syndrome Patients (OCCULT)

Phase II Pilot Randomized-Controlled Trial for the Investigation of the Preliminary Efficacy of Surgical Sectioning of the Filum Terminale in Treating Occult Tethered Cord Syndrome Patients

The investigators hypothesize that surgical release of the filum terminale (strand of fibrous tissue at the end of the spinal cord) is a more efficacious treatment option for symptomatic relief than medical management in subjects with Occult Tethered Cord Syndrome (OTCS) and that the risks do not outweigh the benefit profile.

Study Overview

• Status: Recruiting
• Conditions: Tethered Cord Syndrome; Tethered Cord; Spina Bifida Occulta; Occult Spina Bifida
• Intervention / Treatment: Procedure: Release of filum terminale

Detailed Description

This is a phase II pilot randomized-controlled, single-site trial to determine if surgical untethering of the filum terminale is more effective, preliminarily, than medical management as a treatment option for OTCS. Subjects will be randomized to one of two arms: surgical untethering or medical management only. Symptom improvement and adverse events will be assessed and recorded for 1 year from initiation of treatment. After a minimum of 1 year, subjects who were randomized to the medical management arm may cross over to the surgical arm if the PI deems it is in the subject's best interest to do so. The exploratory hypothesis is that surgery for OTCS is both safe and more effective than medical management at relieving the symptoms of OTCS.

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jeffrey Greenfield, MD, PhD; Phone Number: (212) 746-2363; Email: jpgreenf@med.cornell.edu
• Study Contact Backup: Name: Cynthia Nguyen; Phone Number: (212) 746-1788; Email: cyn4002@med.cornell.edu

Study Locations

• United States
  • New York
    • New York, New York, United States, 10065
      • Recruiting
      • Weill Cornell Medicine
      • Contact: Jeffrey Greenfield, MD, PhD; Phone Number: 212-746-2363; Email: jpgreenf@med.cornell.edu
      • Sub-Investigator: Marissa Michael, MD
      • Contact: Cynthia Nguyen, MsCR; Phone Number: 212-746-1788; Email: cyn4002@med.cornell.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 2 years to 80 years (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Male or female ≥ 2 and < 80 years of age.
• Refractory to medical management of symptoms for at least 1 year.
• Documentation of OTCS, as defined by a total score of at least 30 on the following scale:

OCCULT Grading Scale (Score 0-100) Orthopedic Abnormality: 0-15; Central Nervous System Dysfunction: 0-25; Cutaneous Stigmata: 0-10; Urological or Bowel Dysfunction: 0-25; Lumbosacral Anatomy: 0-15; Tissue Integrity Disorder: 0-10.

Exclusion Criteria:

• Subjects < 2 or > 80 years of age.

• Radiographically identified tethered cord, as defined by any of the following:

  • A low-lying conus (at or below the L2-3 disc space)
  • A thickened filum (>2 mm)
  • Fat in the filum or lipoma
  • Distinct adhesion or tethering.
• A history of Meningocele manqué or Myelomeningocele.
• Cutaneous markings of dermal sinus tract.
• History of prior surgery on the lumbar spine.
• History of prior surgery for spinal dysraphism.
• History of prior infection or autoimmune condition of the central nervous system.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Surgery; Filum release	Procedure: Release of filum terminale; Surgery will be offered to section the filum terminale; Other Names: Laminectomy for tethered cord release
No Intervention: Observation; Medical Management only

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in symptoms related to tethered cord, as measured by the OCCULT Scale	Combination of neurologic, urologic, orthopedic, and cutaneous assessments. The OCCULT Scale is from 0-100, with 0 being none of the listed signs/symptoms present and 100 being all listed signs/symptoms present with maximum severity.	Baseline, 1 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in urologic incontinence score	Score is measured by the International Consultation on Incontinence Questionnaire Urinary Incontinence Short Form. The minimum score is 0 and the maximum score is 21. The higher the score, the more severe the urinary incontinence symptoms and/or effect of symptoms on quality of life.	Baseline, 1 year
Change in fecal incontinence score	Score is measured by the Rapid Assessment Faecal Incontinence Score. The minimum score is 0 and the maximum score is 20. The higher the score, the more severe the fecal incontinence symptoms and/or effect of symptoms on quality of life.	Baseline, 1 year
Number of patients who cross over		1 year
Percent of patients with a decrease in anticholinergic medications at 1 year post-surgery	For patients who presented with urological symptoms	1 year
Number of intra-operative findings that are discordant with MRI interpretations	To examine whether there is a limitation in MRI in identifying pathology that is identified at the time of surgery	Intraoperative

Collaborators and Investigators

• Sponsor: Weill Medical College of Cornell University
• Investigators: Principal Investigator: Jeffrey Greenfield, MD, PhD, Weill Medical College of Cornell University

Publications and helpful links

General Publications

• Michael MM, Garton ALA, Kuzan-Fischer CM, Uribe-Cardenas R, Greenfield JP. A critical analysis of surgery for occult tethered cord syndrome. Childs Nerv Syst. 2021 Oct;37(10):3003-3011. doi: 10.1007/s00381-021-05287-5. Epub 2021 Jul 15.

Study record dates

Study Major Dates

• Study Start (Actual): May 19, 2022
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2027

Study Registration Dates

• First Submitted: November 8, 2021
• First Submitted That Met QC Criteria: December 9, 2021
• First Posted (Actual): December 20, 2021

Study Record Updates

• Last Update Posted (Actual): May 14, 2026
• Last Update Submitted That Met QC Criteria: May 11, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: filum terminale; tethered cord; occult; tight filum
• Additional Relevant MeSH Terms: Central Nervous System Diseases; Nervous System Diseases; Wounds and Injuries; Congenital Abnormalities; Trauma, Nervous System; Spinal Cord Diseases; Nervous System Malformations; Spinal Dysraphism; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Spinal Cord Injuries; Neural Tube Defects; Spina Bifida Occulta; Therapeutics; Surgical Procedures, Operative; Neurosurgical Procedures; Orthopedic Procedures; Decompression, Surgical; Laminectomy
• Other Study ID Numbers: 20-06022262

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No