1. Rib Based Distraction 76% Successful Managing Spinal Muscular Atrophy Scoliosis: A Prospective Study
Sumeet Garg, MD
Jack Flynn, MD
Nicole Michael, BA
Tricia St. Hilaire, MPH
Claire Palmer, MS
Nikki Bloch, BA
Michael Vitale, MD, MPH
Peter Sturm, MD
Mark Erickson, MD, MMM
Children’s Spine Study Group

2. Purpose
In patients with Spinal Muscular Atrophy, to determine if rib based distraction successfully:
prevents further progression of the Cobb angle
allows spinal growth (as measured by trunk height and spinal length)

3. Research Design Prospective multi-center cohort
Pre-determined patient cohort success defined as:
Cobb angle at final surgery is less than or equal to pre-operative Cobb angle and
Trunk height or spinal length at final surgery is greater than or equal to post-operative trunk height or spinal length
Primary hypothesis:
Overall patient success rate exceeds 90%

4. Methods Inclusion criteria Cobb angle >45°
VEPTR device for rib based distraction
No rib abnormalities
18 months to 10 years old
Diagnosis of Spinal Muscular Atrophy (SMA)
Clinical and radiographic information collected
Pre-treatment, post-treatment and most recent follow-up

5. Results 18 patients from 7 sites enrolled Average follow-up 3.0 years
range: years
Overall rib based distraction success rate in this study was 76%
13/17 patients
1 patient excluded because inadequate imaging

6. Results
P-values: Initial to Post (p<0.001), Initial to Most Recent (p<0.001), Post to Most Recent (p<0.001)

7. Results
P-values: Initial to Post (p<0.001), Initial to Most Recent (p=0.003), Post to Most Recent p=0.001)

8. Results 5 disease related complications 1 managed with outpatient care
4 managed with inpatient care
4 device related complications
All managed with planned surgical intervention

9. Conclusion
Rib based distraction treatment for children with SMA did not meet study definition of success
Clinically a 76% improvement in Cobb and spinal height is substantial in this pediatric population
Some patients demonstrated large improvements in scoliosis and spinal height
Others had little benefit

10. Conclusion
Cannot reliably predict which SMA patients will have major improvements in scoliosis and spinal height with rib based distraction treatment

11. References
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2. Hell, A. K.; Campbell, R. M.; and Hefti, F.: [New treatment concept for children with thoracic insufficiency syndrome due to congenital spine deformity.]. Klin Padiatr, 217(5): ,
3. Hell, A. K.; Campbell, R. M.; and Hefti, F.: The vertical expandable prosthetic titanium rib implant for the treatment of thoracic insufficiency syndrome associated with congenital and neuromuscular scoliosis in young children. J Pediatr Orthop B, 14(4): , 2005.
4. Hell, A. K.; Hefti, F.; and Campbell, R. M., Jr.: [Treatment of congenital scoliosis with the vertical expandable prosthetic titanium rib implant]. Orthopade, 33(8): 911-8, 2004.
5. Flynn, J.M.; Skaggs, D. L.; Betz, R.; Smith, J.; et al. VEPTR for early onset scoliosis: a new paradigm for an unsolved problem. International Meeting on Advanced Spine Techniques (IMAST) annual meeting, Banff, Alberta, Canada, July 2005.
6.Campbell RM Jr, Smith MD, Mayes TC, Mangos JA, Willey-Courand DB, Kose N, Pinero RF, Alder ME, Duong HL, Surber JL. The effect of opening wedge thoracostomy on thoracic insufficiency syndrome associated with fused ribs and congenital scoliosis. J Bone Joint Surg Am Aug;86-A(8):
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