ICEOS 2015

Bilateral rib-to-pelvis VEPTR therapy duplicates normal height gain of lumbar vertebral growth in neuromuscular scoliosis

P. Kunkel, N. Floeter, C. Hagemann, K. Ridderbusch, M. Rupprecht and R. Stücker Departments of Pediatric Orthopedics and Pediatric Neurosurgery Altona Children‘s Hospital, Hamburg, Germany Introduction

Vertical Expandable Prostetic Titanium Rib (VEPTR) – Therapy:

• Non-fusion technique in early onset scoliosis • Rib-to-rib and rib-to-lamina constructs are used in ambulatory children with congenital malformations most often involving the thorax • In neuromuscular scoliosis and non-ambulatory children rib-to-pelvis (Eiffeltower) constructs help to achieve improvement and control of the deformity during growth

Samdani et al.: Bilateral use of the vertical expandable prosthetic titanium rib attached to the pelvis: a novel treatment for scoliosis in the growing spine, J Neurosurg Spine, 2009

Abol Oyoun et al.: Bilateral rip-to pelvis Eiffel Tower VEPTR construct for children with neuromuscular scoliosis: a preliminary report, The Spine Journal, 2014 Introduction

Impact on growth patterns of vertebrae

• Observation of characteristic barrel-shaped lumbar vertebrae during the course of Eiffeltower VEPTR therapy • Effect not apparent in thoracic vertebrae

Study:

• Growth velocity of height and width of lumbar and thoracic vertebrae over the course of VEPTR Eiffeltower treatment in neuromuscular scoliosis patients Patients

N total 26 Boys 16 Girls 10 Age at index surgery 8,6 years Follow up 46 months (range: 9-89) Myopathy / Muscular dystrophy 7 Spinal muscular atrophy (SMA) 5 Syndrome 8

SpinaCerebral bifida cases palsy excluded / Spasticity because of altered 6 vertebral morphology

X-rays every 6 months at lengthening procedure Methods

Digital measurement of height and width of L5 (lowest lumbar vertebra) and topmost thoracic vertebra within instrumentation (in most cases T3 or T4)

after index surgery 2 years later Methods

after index surgery 2 years later Methods

after index surgery 2 years later

Growth velocity: Measurements post index surgery vs. last follow up Results

Vertebral growth velocity (means)

Height growth per Standard Standard year deviation error

L5 2,0 mm 0,6 0,07 Difference: L5 standard * 0,9 mm p=0,000003 T3 0,6 mm 0,7 0,08

T3 standard * 0,6 mm

Width growth Standard Standard per year deviation error

L5 0,4 mm 1,3 0,33 Difference: L5 standard * 1 mm p=0,06 T3 0,6 mm 0,9 0,16

T3 standard * 0,6 mm

* Dimeglio A. & Bonnel F.: The Growing Spine. Paris: Springer-Verlag (1990) Hong Zhang et al : Morphometric Analysis of the Vertebral Growth Using Magnetic Resonance Imaging in the Normal Skeletally Immature Spine . Spine (2010) Discussion

• Height growth velocity of L5 under VEPTR-Eiffeltower traction doubled and width growth velocity halved compared to normal data > Faster growth of appendicular growth plates under traction due to load reduction (Hueter-Volkmann principle) (* 1,2)

• Height and width growth velocity of T3 under traction identical to normal data > Preservation of normal growth pattern effect of traction (* 3,4) > Lesser effect on thoracic vertebrae due to attenuation of load reduction by rib cage (* 1)

• VEPTR-Eiffeltower therapy achieved stimulation (lumbar spine) and preservation (thoracic spine) of vertebral growth in neuromuscular scoliosis > Attainment of critical thoracic height of 18 cm (* 5)

* 1) Stokes I. et al.: Mechanical modulation of vertebral body growth. Spine 1996 2) Dimeglio A. et al.: The growing spine: how spinal deformities influence normal spine and thoracic cage growth. Eur Spine J 2012 3) Olgun ZD. Et al.: Vertebral body growth during growing rod instrumentation: growth preservation or stimulation? JPO 2012 4) Akbarnia BA et al: Fusionless procedures for the management of early–onset spine deformities. J Child Orthop 2011 5) Karol LA et al: Pulmonary function following early thoracic fusion in non neuromuscular scoliosis. J Bone Joint Surg Am 2006 Conclusion

VEPTR-Eiffeltower treatment in neuromuscular scoliosis: a.Stimulation of longitudinal growth of lumbar vertebrae beyond normal growth velocity b.Reduction of normal horizontal growth of lumbar vertebrae c.Preservation of normal growth in height and width of thoracic vertebrae Altona Children’s Hospital, Hamburg / Germany 1965: 1985: 2005: Anterio Cotrel- Pedicle r Dubousse screws Fusion t only

− Pediatric Spine Center− Pediatric Orthopedics and Pediatric Neurosurgery