The Tether™ - Vertebral Body Tethering System Post Approval Study

ZimVie

Status

Enrolling

Conditions

Scoliosis Idiopathic

Treatments

Device: Anterior Vertebral Body Tethering

Study type

Observational

Funder types

Other

Industry

Identifiers

NCT04505579

RAU2019-40S

Details and patient eligibility

About

This study is an opportunity to provide continued reasonable assurance of the safety and probable benefit of The Tether HUD. The study will collect long term safety and efficacy information from patients who have had their idiopathic scoliosis treated via anterior vertebral body tethering (AVBT) with The Tether.

Full description

While spinal fusion remains the standard surgical treatment for progressive idiopathic scoliosis, concerns about the long-term effects of spinal fusion have led to the investigation of growth-modulation techniques. Anterior Vertebral Body Tethering (AVBT) is one such technique that utilizes growth modulation to remodel the shape of the vertebra and straighten scoliotic curves in skeletally immature individuals. In this technique, screws are inserted at each vertebral level for the length of the convex side of the curve. A strong cord is connected through the screw tulip heads and used to initially straighten the curve as each level is fixed with a set screw. Following surgery and during the growth period the spine begins to remodel according to the Hueter-Volkmann Law, bone growth is relatively inhibited in areas of increased pressure (convex or tethered side) and relatively stimulated in areas of decreased pressure or tension (concave side). Following this principle, AVBT has been shown to alter spinal growth with the potential to correct scoliosis while maintaining spine flexibility.

The objective of the study is to assess the ongoing safety and probable benefit of The Tether HUD which was approved by the FDA under an HDE. Subject enrollment and data collection will be managed by the Harms Study Group (HSG) and Setting Scoliosis Straight Foundation (SSSF) Registry. Institutions that are HSG members or affiliates, with Investigators/surgeons that are trained and approved to perform surgeries with The Tether, will participate in the registry. Ten sites from this group will be identified as study sites specific to this Tether post-approval study (PAS). Consecutive subjects from these sites, that meet the eligibility criteria of this study, will be flagged in the registry as the PAS cohort and the study endpoints will be assessed across this population.

Enrollment

200 estimated patients

Sex

All

Volunteers

No Healthy Volunteers

Inclusion criteria

Diagnosis of progressive idiopathic scoliosis
Skeletally immature, based on both Risser (<5) and Sanders (<8) assessments
Major Cobb angle ≥30° and ≤65°
Osseous structure dimensionally adequate to accommodate screw fixation, as determined by radiographic imaging
Failed or intolerant to bracing

Exclusion criteria

Presence of any systemic infection, local infection, or skin compromise at the surgical site
Prior spinal surgery at the level(s) to be treated
Documented poor bone quality, defined as a T-score -1.5 or less
Any other medical or surgical condition which would preclude the potential benefit of spinal surgery, such as coagulation disorders, allergies to the implant materials, and patient's unwillingness or inability to cooperate with post-operative care instructions
Unwillingness, inability, or living situation (e.g. custody arrangements, homelessness, detention) that would preclude ability to return to the study site for follow-up visits as described in protocol and Informed Consent
Unwillingness to sign Informed Consent Form and participate in study procedures