Efficacy of Sub-laminar and/or Interspinous Tethers to Prevent Proximal Junctional Kyphosis After Surgical Correction of Adult Spinal Deformity

NCT07618897 | Not Yet Recruiting

• 2 other identifiers: 69HCL24_07202026-A00732-49
• Study Type: interventional
• Target: 128
• Locations: 1 country
• Sites: 1

Brief Summary

PJK (proximal junctional kyphosis) at the upper end of spinal fusions after surgical correction of adult spinal deformity is not uncommon. Two-thirds of cases are observed within the first 3 months after surgery and 80% within the first 18 months. PJK is consequently a common problem after surgery for adult spinal deformity, representing one of the most frequent complications following this kind of procedure. Although the first-line treatment of this event is conservative, surgery may be necessary in around 30-40% of cases. Revision surgery generally consists of extending the posterior spinal instrumentation. Prophylactic vertebroplasty has been proposed to reduce the risk of PJK and PJF, with promising results but with the limitation of reinforcing only the bony structures, with no action on the soft tissues. In this context, some authors have reported that the use of tethers, creating a transitional zone at the upper end of the construct between the fused and the non-instrumented spine, could reduce the occurrence of this complication (PJK). One of the hypotheses is that the use of a topping-off system results in a transitional zone reducing stresses at the junctional spine and may reduce the occurrence of both PJK and the need for reoperation. Compared with other topping-off systems, such as hooks, the surface of contact provided by the bands on the posterior arches is much greater and the primary stability much better. In addition, the risk of malposition is extremely low. The aim of this study is therefore to compare the occurrence of PJK and PJF in patients for whom tethers were implanted at the upper end of the instrumentation versus patients for whom no tether system was used. In a retrospective study conducted in the neurosurgery department of the HCL on 38 patients undergoing multilevel spine instrumentation with junctional tethers, PJK occurred in 8 of them (21%) after 24 months of follow-up.

Conditions

Proximal Junctional Kyphosis

Outcome Measures

Primary Outcomes (1)

• Sub-laminar and/or interspinous tethers efficacy to prevent PJK

  Percentage of patients with PJK during the first post-operative 24 months with PJK defined as : * a proximal junctional sagittal Cobb angle (PJA) between the lower endplate of uppermost instrumented vertebra (UIV) with screws and the upper endplate of 2 supra-adjacent vertebra ≥15 * a 15° delta between 24months post operative PJA and preoperative PJA These 2 parameters will be assessed by an independent committee using radiographic images preop and 24 months postop

  From enrollment to 24 months post-surgery

Secondary Outcomes (7)

• Sub-laminar and/or interspinous tethers efficacy to prevent PJF

  From enrollment to 24 months post-surgery

• Sub-laminar and/or interspinous tethers efficacy to prevent surgery revision

  From enrollment to 24 months post-surgery

• Sub-laminar and/or interspinous tethers efficacy to prevent the level of disabilty

  From enrollment to 24 months post-surgery

• Sub-laminar and/or interspinous tethers efficacy to prevent pain

  From enrollment to 24 months post-surgery

• Sub-laminar and/or interspinous tethers efficacy to enhance quality of life

  From enrollment to 24 months post-surgery

Study Arms (2)

Patient instrumented with a tether

EXPERIMENTAL

Sub-laminar and/or interspinous tethers

Device: Tether strategy

Reference strategy

ACTIVE COMPARATOR

Standard surgery

Procedure: Reference

Interventions

Tether strategy DEVICE

During spine surgery sub-laminar or interspinous bands are utilized in combination with standard posterior rigid instrumentation (i.e. screws and metallic rods). They are typically implanted at the upper vertebral level, above the cranial screws, and then connected to the rods. Their implantation is based on standard surgical techniques for spine surgeons.

Patient instrumented with a tether

Reference PROCEDURE

Patient will undergo the spine surgery as the standard of care, using only standard posterior rigid instrumentation (i.e. screws and metallic rods).

Reference strategy

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patient men and women older than 18
• Patient indicated spinal posterior fusion and instrumentation with the upper end (UIV with screws) between T9 and L2 and the lower end between L5 and iliac
• Constructs ≥4 levels (i.e., ≥4 discs included)
• Patient able to signed a consent form
• Patient able to fill a self-administered questionnaire
• Patient affiliated to health care insurance (social security in France

You may not qualify if:

• Allergy to metal
• Cimentoplasty at the junctional zone (UIV, UIV+1 and/or UIV+2)
• Bone metabolism disorders that potentially compromise the mechanical support expected from this type of implant.
• Morbid obesity (BMI \> 40)
• Patients with infection (in particularly osteomyelitis)
• Cancer of lesss than 5 years or currently treated
• Acute trauma
• Immunodepression
• Parkinson
• Chronic inflammatory disease
• Severe psychological disorders
• Pregnancy or women breastfeeding
• Inadequate tissue coverage of implant site,
• Interference with other critical anatomical structures.
• Patient not being able to understand the objectives of the study or refusing to comply with postoperative instructions

Sponsors & Collaborators

• Hospices Civils de Lyon: lead

Study Sites (1)

Hôpital Pierre Wertheimer - Hospices Civils de Lyon, Service de Neurochirurgie - Chirurgie du Rachis et de la Moëlle Epinière

Lyon, 69394, France

Location

Study Officials

• Cédric BARREY, Ph

  Hospices Civiles de Lyon

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Cédric BARREY, Ph

CONTACT

+33 4 72 11 80 67; cedric.barrey@chu-lyon.fr

Julien BERTHILLER

CONTACT

+33 4 27 85 63 01; julien.berthiller@chu-lyon.fr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 13, 2026
• First Posted: June 1, 2026
• Study Start: June 22, 2026
• Primary Completion (Estimated): June 22, 2030
• Study Completion (Estimated): June 22, 2030
• Last Updated: June 1, 2026

Record last verified: 2026-05

Locations

FR (1)