Surgical Sectioning for Tethered Cord Syndrome

(OCCULT Trial)

Overseen by Jeffrey Greenfield, MD, PhD

Age: Any Age

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Phase 2

Recruiting

Sponsor: Weill Medical College of Cornell University

Disqualifiers: Radiographic tethered cord, Prior lumbar surgery, CNS infection, others

No Placebo Group

Prior Safety Data

Approved in 2 Jurisdictions

Trial Summary

What is the purpose of this trial?

This trial is testing whether a surgery to cut a small piece of tissue at the end of the spinal cord is better than standard medical treatments for patients with Occult Tethered Cord Syndrome (OTCS). These patients often do not find relief from typical treatments. The surgery aims to relieve pressure and tension in the spinal cord, which may help improve their symptoms. This surgical method is currently the most widely accepted treatment for OTCS.

Do I need to stop my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What data supports the effectiveness of the treatment for tethered cord syndrome?

The release of a tethered spinal cord by sectioning a thickened filum terminale is a straightforward surgical procedure that can prevent, arrest, or improve neurological deficits, although there is a risk of retethering and potential need for reoperation. ^{1 2 3 4 5}

Is the surgical sectioning of the filum terminale generally safe?

Surgical sectioning of the filum terminale is generally considered safe, but there is a risk of nerve injury and retethering (the spinal cord becoming tethered again) after the procedure. Using special monitoring during surgery can help reduce nerve injury, and certain techniques may help prevent retethering. ^{1 2 3 6 7}

How is the treatment 'Release of filum terminale' unique for tethered cord syndrome?

The 'Release of filum terminale' is a surgical procedure specifically designed to address tethered cord syndrome by cutting the filum terminale (a thread-like structure in the spine) to relieve tension on the spinal cord, which is different from other treatments that may not directly target the source of the tethering. ^{8 9 10 11 12}

Research Team

Jeffrey Greenfield, MD, PhD

Principal Investigator

Weill Medical College of Cornell University

Eligibility Criteria

This trial is for people aged 2 to 79 with Occult Tethered Cord Syndrome (OTCS) who haven't improved after at least a year of medical treatment. They must score at least 30 on the OCCULT Grading Scale. It's not for those with visible signs of spinal issues, previous lumbar spine or spinal dysraphism surgeries, or a history of central nervous system infections or autoimmune diseases.

Inclusion Criteria

You have been diagnosed with Tethered Cord Syndrome

You have a total score of at least 30 on the OCCULT Grading Scale, which measures a type of skin condition.

I am between 2 and 79 years old.

Exclusion Criteria

I have a history of spinal cord issues related to Meningocele or Myelomeningocele.

I have had surgery on my lower back before.

I have visible skin markings indicating a dermal sinus tract.

Trial Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants are randomized to either surgical untethering of the filum terminale or medical management

1 year

Regular visits for symptom assessment and adverse event monitoring

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Crossover

Subjects in the medical management arm may cross over to the surgical arm if deemed beneficial

After 1 year

Treatment Details

Interventions

• Release of filum terminale (Procedure)

Trial Overview The study tests if cutting the filum terminale—a fibrous tissue at the end of the spinal cord—is better than standard medical care in relieving symptoms of OTCS. The hypothesis suggests surgery could be more effective and that benefits may outweigh risks.

Participant Groups

Group I: Surgery Active Control 1 Intervention

Filum release

Group II: Observation Active Control 1 Intervention

Medical Management only

Who Is Running the Clinical Trial?

Weill Medical College of Cornell University

Lead Sponsor

Trials

1,103

Recruited

1,157,000+

Dr. Robert Min

Weill Medical College of Cornell University

Chief Executive Officer since 2024

MD, MBA

Dr. Adam R. Stracher

Weill Medical College of Cornell University

Chief Medical Officer since 2024

MD

Findings from Research

Retethering of the spinal cord can occur years after the surgical release of a tethered cord, as seen in two 13-year-old patients who experienced neurological deterioration due to this rare complication.

Surgical exploration and rerelease of the retethered filum terminale led to stabilization of bladder dysfunction and improvement in motor function, highlighting the importance of careful long-term monitoring and intervention for patients with a history of tethered spinal cord.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Retethering of sectioned fibrolipomatous filum terminales: report of two cases. Souweidane, MM., Drake, JM.[2019]

In a review of 146 children who underwent surgery for tethered cord syndrome, 7.5% experienced retethering, with 36% of those initially asymptomatic at the time of their first surgery.

Repeat surgery for retethering was effective in alleviating new symptoms, suggesting that while some asymptomatic children may improve after surgery, they might not have needed the initial procedure.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Retethering in children after sectioning of the filum terminale. Vassilyadi, M., Tataryn, Z., Merziotis, M.[2018]

In a study of 15 adult patients undergoing tethered cord release, intraoperative neurophysiological monitoring significantly reduced the risk of nerve root injury, with no new neurological symptoms reported post-surgery.

The use of electrical stimulation revealed a dramatic difference in response thresholds between the filum terminale and motor nerve roots (100:1), aiding in the safe sectioning of the filum and resulting in improved bowel and bladder function in 46% of patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Neurophysiological monitoring for safe surgical tethered cord syndrome release in adults. Quiñones-Hinojosa, A., Gadkary, CA., Gulati, M., et al.[2004]

A new microsurgical technique for treating tethered cord syndrome involves transecting the filum terminale below the conus tip, which may improve surgical outcomes by minimizing remnants of the filum.

This approach allows for complete removal of the distal portion of the filum through a less invasive interlaminar method, potentially reducing complications associated with traditional laminectomy techniques.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Microsurgical approach for resection of the filum terminale internum in tethered cord syndrome-a case demonstration of technical nuances and vignettes. Abdulrazeq, H., Shao, B., Sastry, RA., et al.[2023]

In a study of 248 patients under 18 years old who underwent tethered cord release surgery, both laminotomy and laminoplasty techniques showed no significant difference in early complication rates, with only 3.6% experiencing complications post-surgery.

Regardless of the surgical technique used, 97% of caregivers reported improvement in their child's condition after the procedure, indicating high efficacy of the surgery for treating tethered cord syndrome.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Use of lumbar laminoplasty vs. laminotomy for transection of the filum terminale does not affect early complication rates or postoperative course. Strong, MJ., Thompson, EM., Roundy, N., et al.[2021]

In a study of 342 patients who underwent untethering surgery for a tight filum terminale, the retethering rate was only 1.2%, which is lower than rates reported in previous studies, indicating the procedure's effectiveness.

By sectioning the filum terminale at a rostral level to the dural incision, the authors found this technique significantly reduced the occurrence of retethering, suggesting a safer surgical approach with favorable long-term outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Prevention of retethering in untethering surgery of a tight filum terminale. Ogawa, S., Ogiwara, H.[2023]

In a study of 152 patients who underwent section of a tight filum terminale, 8.6% experienced symptomatic retethering, with a median time of 23.4 months post-surgery, indicating that retethering is a notable risk even after this minimally invasive procedure.

Two patterns of retethering were identified: early retethering was associated with older age at surgery and more complications like arachnoiditis, while late retethering was linked to younger patients who had surgery earlier to prevent tethered cord symptoms.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Symptomatic retethering of the spinal cord after section of a tight filum terminale. Yong, RL., Habrock-Bach, T., Vaughan, M., et al.[2011]

The liver hanging maneuver (LHM) was associated with lower intraoperative blood loss and no need for blood transfusions in patients undergoing anatomical hepatectomy for large liver tumors, suggesting it may enhance safety during surgery.

Patients who underwent LHM had a shorter hospital stay and did not experience post-hepatectomy liver failure or bile leakage, indicating improved outcomes compared to those who did not receive the maneuver.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Liver hanging maneuver is suitable in major hepatectomy for liver malignancies over 5 cm. Nanashima, A., Hiyoshi, M., Imamura, N., et al.[2023]

The study of 43 cadaveric livers revealed that the left triangular ligament (LTL) is closely attached to the appendix fibrosa hepatis (AFH), which can lead to accidental dissection of the AFH during surgical procedures.

Surgeons are advised to ligate the AFH securely rather than using electrocautery alone, as the AFH often contains large bile ducts and vascular structures that could complicate surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Reconfirmation of the anatomy of the left triangular ligament and the appendix fibrosa hepatis in human livers, and its implication in abdominal surgery. Kogure, K., Kojima, I., Kuwano, H., et al.[2016]

The modified hanging maneuver using the Goldfinger dissector in laparoscopic liver resection was performed on 18 patients, demonstrating a median resection time of 96 minutes and minimal blood loss of 220 ml, indicating its efficacy and safety.

Only two complications (11%) were reported, which resolved spontaneously, suggesting that this technique is safe for use in major hepatectomies without the need for conversion to open surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Modified hanging maneuver using the goldfinger dissector in laparoscopic right and left hepatectomy. Troisi, RI., Montalti, R.[2019]

The liver hanging maneuver was successfully performed in 47 cases, demonstrating its feasibility and safety in protecting the inferior vena cava (IVC) during hepatectomy, with only one case experiencing severe bleeding.

This technique allows for clearer exposure of intrahepatic vessels and the ductal system, making the anterior approach for liver surgery safer and easier.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[The significance of liver hanging maneuver in liver-splitting anterior approach for hepatectomy]. Peng, SY., Qian, HR., Li, JT., et al.[2005]

In a study of 1,451 patients undergoing liver resection, the conventional liver mobilization approach was successful in 99.6% of cases, indicating its overall safety and efficacy.

Tape-assist techniques were used in 2.9% of cases to manage complex surgical situations, showing that while the conventional method is effective, tape-assist can enhance safety in specific circumstances without significantly affecting morbidity or survival rates.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Significance of liver hanging maneuvers for invasive liver lesions in no-routine anterior approach policy. Shindoh, J., Hasegawa, K., Aoki, T., et al.[2021]

References

1. United States pubmed.ncbi.nlm.nih.gov

Retethering of sectioned fibrolipomatous filum terminales: report of two cases. [2019]

2. Switzerland pubmed.ncbi.nlm.nih.gov

Retethering in children after sectioning of the filum terminale. [2018]

3. United States pubmed.ncbi.nlm.nih.gov

Neurophysiological monitoring for safe surgical tethered cord syndrome release in adults. [2004]

4. Austria pubmed.ncbi.nlm.nih.gov

Microsurgical approach for resection of the filum terminale internum in tethered cord syndrome-a case demonstration of technical nuances and vignettes. [2023]

5. Germany pubmed.ncbi.nlm.nih.gov

Use of lumbar laminoplasty vs. laminotomy for transection of the filum terminale does not affect early complication rates or postoperative course. [2021]

6. United States pubmed.ncbi.nlm.nih.gov

Prevention of retethering in untethering surgery of a tight filum terminale. [2023]

7. United States pubmed.ncbi.nlm.nih.gov

Symptomatic retethering of the spinal cord after section of a tight filum terminale. [2011]

8. Turkey pubmed.ncbi.nlm.nih.gov

Liver hanging maneuver is suitable in major hepatectomy for liver malignancies over 5 cm. [2023]

9. Japan pubmed.ncbi.nlm.nih.gov

Reconfirmation of the anatomy of the left triangular ligament and the appendix fibrosa hepatis in human livers, and its implication in abdominal surgery. [2016]

10. Switzerland pubmed.ncbi.nlm.nih.gov

Modified hanging maneuver using the goldfinger dissector in laparoscopic right and left hepatectomy. [2019]

11. China pubmed.ncbi.nlm.nih.gov

[The significance of liver hanging maneuver in liver-splitting anterior approach for hepatectomy]. [2005]

12. United States pubmed.ncbi.nlm.nih.gov

Significance of liver hanging maneuvers for invasive liver lesions in no-routine anterior approach policy. [2021]