Clinical Assessment of a Motorized Spinal Distraction Rod in the Severe to Early Scoliosis Child (ASTS)

The purpose of this biomedical research is to evaluate the feasibility of the treatment with the new spinal distraction device ASTS in patients aged 4 to 10 years with severe early onset scoliosis.

The hypothesis of this project is that the new fully implantable motorized spinal distraction device may provide a correction of scoliosis and progressive elongation ensuring patient comfort and minimizing complications.

The ASTS (for Active Scoliosis Treatment System) growing rod is a new fully implantable motorized spinal distraction device which can ensure a correction of scoliosis and progressive elongation ensuring patient comfort and minimizing complications.

Study Overview

• Status: Active, not recruiting
• Conditions: Scoliosis
• Intervention / Treatment: Device: ASTS

Detailed Description

Despite a better understanding and technical progress, the evolutionary early scoliosis remains a therapeutic challenge. The definition includes idiopathic scoliosis beginning before the age of 3 years, congenital scoliosis, neuromuscular and syndromic. Spinal deformity is often progressive and may compromise cardiorespiratory function.

The goal of treatment is to prevent further avoiding spinal fusion in a subject in growth. Surgery is indicated in case of failure or cons-indication of conservative treatment (corset or plaster). The principle is to position the posterior rods subcutaneous or in muscle attached to two ends of the deformation.

Intraoperative distraction allows correction of the deformity. A new distraction is performed every 6 months until skeletal maturity.

Considerable complication rates are reported (58%), mainly implant infections and disassembly, because of the need for multiple reoperations. Motorized implants can potentially avoid repeated interventions limiting complications.

Thus, the central hypothesis of this project is a new fully implantable motorized spinal distraction device may provide a correction of scoliosis and progressive elongation ensuring patient comfort and minimizing complications.

• Study Type: Interventional
• Enrollment (Actual): 5
• Phase: Not Applicable

Contacts and Locations

Study Locations

• France
  • Toulouse, France, 31000
    • CHU de Toulouse

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 4 years to 10 years (Child)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patient 4 to 10 years
• Patient weight between 15kg at 50kg
• Introducing severe scoliosis (Cobb angle> 40 °) with early onset
• Failed or cons-indication of conservative treatment (cast or brace)
• Agreement of parents or legal guardian (written agreement) and the patient (at least an oral agreement).

Exclusion Criteria:

• Contraindication to surgery
• Age less than 4 years or above 10 years
• Weight less 15kg and above 50 kg

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ASTS device; Implantation of device ASTS (for ACTIVE TREATMENT SCOLIOSIS SYSTEM ) in children between 4 and 10	Device: ASTS; Implantation of a motorized spinal distraction rod

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ability to Implant the device	The surgeon will have to say if the implantation of the device has been done or not	Day 0: the day of the implantation
Change of the position of the implant	1 year after the implantation of the device, radiographs will be realised to ensure that the implant is still well positioning	1 years after the implantation
Change of the position of the implant	2 years after the implantation of the device, radiographs will be realised to ensure that the implant is still weel positioning	2 years after the implantation
Change of the position of the implant	3 years after the implantation of the device, radiographs will be realised to ensure that the implant is still weel positioning	3 years after the implantation
Change of the implant's length	The elongation of the implant will be measured in mm on the digital radiography	3 months, 6 months, 9 months, 1 year, 2 years and 3 years after the implantation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Post-surgical pain	Self-assessment of pain using a visual analog scale	3 months, after the implantation
Post-surgical pain	Self-assessment of pain using a visual analog scale	months after the implantation
Post-surgical pain	Self-assessment of pain using a visual analog scale	9 months after the implantation
Post-surgical pain	Self-assessment of pain using a visual analog scale	1 year after the implantation
Survey to evaluate the quality of life	Assess quality of life in the questionnaire PedsQL	Day 0
Survey to evaluate the quality of life	Assess quality of life in the questionnaire PedsQL	6 months after the implantation
Survey to evaluate the quality of life	Assess quality of life in the questionnaire PedsQL	1 year after the implantation
to ease for the surgeon to implant the device,	Number of participant with ease for the surgeon to implant the device,	Day 0
wound closure without tension,	Number of participant with closure of the wound without tension,	Day 0
good positioning of the radiographic implant.	Number participant with good positioning of the radiographic implant.	Day 0
Number of medical visits	Measure of the number of medical visit in the year after implant	1 year
Determine the number of iterative extensions made during follow-up	Number of iterative extensions of 1 year.	1 year
correction of deformation immediately after the operation,	Number of participant with correction of deformation immediately after the operation,	3 months, 6 months, 9 month and 1 year
correction of deformation immediately after the operation,	Number of participant with correction of deformation immediately after the operation,	3 months after implantation
Loss correction at 1 year	Loss correction at 1 year	6 months after implantation
Loss correction at 1 year	Loss correction at 1 year	9 month after implantation
Loss correction at 1 year	Loss correction at 1 year	1 year after implantation
Increase the distance T1-S1 at 1 year	Increase the distance T1-S1 at 1 year (in mm)	1 year
Effective Elongation measured on radiographs of specification of the device (in mm)	Effective Elongation measured on radiographs of specification of the device (in mm)	3 months after implantation
Effective Elongation measured on radiographs of specification of the device	Effective Elongation measured on radiographs of specification of the device (in mm)	6 months after implantation
Effective Elongation measured on radiographs of specification of the device	Effective Elongation measured on radiographs of specification of the device (in mm)	9 month after implantation
Effective Elongation measured on radiographs of specification of the device	Effective Elongation measured on radiographs of specification of the device (in mm)	1 year after implantation
Nature of complications	describe the nature of complication	1 years
Nature of complications	describe the nature of complication	2 years
Nature of complications	describe the nature of complication	3 years
Nature of complications	describe the nature of complication	5 years

Collaborators and Investigators

• Sponsor: University Hospital, Toulouse
• Investigators: Principal Investigator: Franck Accadbled, MD PhD, University Hospital, Toulouse

Publications and helpful links

General Publications

• Varni JW, Seid M, Kurtin PS. PedsQL 4.0: reliability and validity of the Pediatric Quality of Life Inventory version 4.0 generic core scales in healthy and patient populations. Med Care. 2001 Aug;39(8):800-12. doi: 10.1097/00005650-200108000-00006.
• Bess S, Akbarnia BA, Thompson GH, Sponseller PD, Shah SA, El Sebaie H, Boachie-Adjei O, Karlin LI, Canale S, Poe-Kochert C, Skaggs DL. Complications of growing-rod treatment for early-onset scoliosis: analysis of one hundred and forty patients. J Bone Joint Surg Am. 2010 Nov 3;92(15):2533-43. doi: 10.2106/JBJS.I.01471. Epub 2010 Oct 1.
• Varni JW, Burwinkle TM, Seid M, Skarr D. The PedsQL 4.0 as a pediatric population health measure: feasibility, reliability, and validity. Ambul Pediatr. 2003 Nov-Dec;3(6):329-41. doi: 10.1367/1539-4409(2003)0032.0.co;2.
• Akbarnia BA, Marks DS, Boachie-Adjei O, Thompson AG, Asher MA. Dual growing rod technique for the treatment of progressive early-onset scoliosis: a multicenter study. Spine (Phila Pa 1976). 2005 Sep 1;30(17 Suppl):S46-57. doi: 10.1097/01.brs.0000175190.08134.73.
• Lucas G, Bollini G, Jouve JL, de Gauzy JS, Accadbled F, Lascombes P, Journeau P, Karger C, Mallet JF, Neagoe P, Cottalorda J, De Billy B, Langlais J, Herbaux B, Fron D, Violas P. Complications in pediatric spine surgery using the vertical expandable prosthetic titanium rib: the French experience. Spine (Phila Pa 1976). 2013 Dec 1;38(25):E1589-99. doi: 10.1097/BRS.0000000000000014.
• Krieg AH, Speth BM, Foster BK. Leg lengthening with a motorized nail in adolescents : an alternative to external fixators? Clin Orthop Relat Res. 2008 Jan;466(1):189-97. doi: 10.1007/s11999-007-0040-3. Epub 2008 Jan 3.
• Baumgart R. The reverse planning method for lengthening of the lower limb using a straight intramedullary nail with or without deformity correction. A new method. Oper Orthop Traumatol. 2009 Jun;21(2):221-33. doi: 10.1007/s00064-009-1709-4.
• den Uil CA, Bezemer R, Miranda DR, Ince C, Lagrand WK, Hartman M, Bogers AJ, Spronk PE, Simoons ML. Intra-operative assessment of human pulmonary alveoli in vivo using Sidestream Dark Field imaging: a feasibility study. Med Sci Monit. 2009 Oct;15(10):MT137-141.
• Kanter KR, Haggerty CM, Restrepo M, de Zelicourt DA, Rossignac J, Parks WJ, Yoganathan AP. Preliminary clinical experience with a bifurcated Y-graft Fontan procedure--a feasibility study. J Thorac Cardiovasc Surg. 2012 Aug;144(2):383-9. doi: 10.1016/j.jtcvs.2012.05.015. Epub 2012 Jun 13.
• Kerimaa P, Ojala R, Sinikumpu JJ, Hyvonen P, Korhonen J, Markkanen P, Tervonen O, Sequeiros RB. MRI-guided percutaneous retrograde drilling of osteochondritis dissecans of the talus: a feasibility study. Eur Radiol. 2014 Jul;24(7):1572-6. doi: 10.1007/s00330-014-3161-6. Epub 2014 Apr 17.
• Flynn JM, Emans JB, Smith JT, Betz RR, Deeney VF, Patel NM, Campbell RM. VEPTR to treat nonsyndromic congenital scoliosis: a multicenter, mid-term follow-up study. J Pediatr Orthop. 2013 Oct-Nov;33(7):679-84. doi: 10.1097/BPO.0b013e31829d55a2.
• Noordeen HM, Shah SA, Elsebaie HB, Garrido E, Farooq N, Al-Mukhtar M. In vivo distraction force and length measurements of growing rods: which factors influence the ability to lengthen? Spine (Phila Pa 1976). 2011 Dec 15;36(26):2299-303. doi: 10.1097/BRS.0b013e31821b8e16.

Study record dates

Study Major Dates

• Study Start (Actual): February 5, 2019
• Primary Completion (Estimated): December 1, 2025
• Study Completion (Estimated): December 1, 2025

Study Registration Dates

• First Submitted: July 11, 2016
• First Submitted That Met QC Criteria: October 30, 2017
• First Posted (Actual): November 6, 2017

Study Record Updates

• Last Update Posted (Estimated): September 8, 2025
• Last Update Submitted That Met QC Criteria: September 1, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Bone Diseases; Musculoskeletal Diseases; Spinal Diseases; Spinal Curvatures; Scoliosis
• Other Study ID Numbers: RC31/15/7851

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
• product manufactured in and exported from the U.S.: No