Fusionless Correction for Early Onset Scoliosis (EOS) Emma Orton BME 281

What is EOS? Diagnosed before the skeletal age of 10 There is a lateral curve of the spine Causes pulmonary problems later in life There are three different types – Infantile Idiopathic- diagnosed between 0 and 3 years old and the patient is otherwise healthy – Juvenile Idiopathic-diagnosed between 4 and 10 years old – Congenital-is developed within the first 6 weeks of embryonic formation and is when vertebrae are not formed correctly [1]

Cobb Angle [2]

[3]

Possible Treatments Braces For older patients with a less severe curve will not be helpful for patients aged 2-7 years with curves of 50 to 60 degrees VECTR Vertical prosthetic titanium prosthetic rib Pushes ribs apart widening the thorax and straightening the spine Dual Growing Rods Growing Rods with Magnetic Expansion Control Spinal Fusion Many other surgical treatments

Why are Fusionless Treatments Better? When fusion is used the curve of the spine is improved but growth stops Fusionless treatments are important for children especially those under 10 Children under 5 still have up to 12.5 cm of vertical growth Lungs do not fully develop till about 8 years old Fusion does work for patients who are fully grown [4]

Criteria for Dual Growing Rods The general criteria is: Significant potential axial growth remaining A deformity that is continuing to progress A deformity that is flexible or can be made flexible

Dual Growing Rods: Experiment 1 38 patients Followed for anywhere between 2 and 7 years (on average 3.3 years) Patients received lengthenings on average every 6.8 months The cobb angle decreased from 74 degrees to 38 degrees on average There was axial growth (T1-S1) [5]

Dual Growing Rod: Experiment 2 23 patients Cobb angle corrected from 82 degrees to 38 degrees on average On average 1.24cm per year of axial spinal growth Improvement of space in the thorax 13 complications with 11 patients

Dual Growing Rod: Experiment 3 Group 1 had a single rod with a short apical fusion Group 2 had only a single rod Group 3 had dual rod implantation Group 1 had the worst results with 23% correction (6.4cm of axial growth) while group three had the best with 71% correction (12.1 cm of axial growth)

Pros and Con of Dual Growing Rod One of the most efficient ways of treating EOS Opens up the thorax preventing many future pulmonary issues Continues to allow for growth Each patient must receive an invasive surgery every six months for a span of a few years (usually till age 10 for girls and age 13 for boys) This leads to more opportunities to contract some kind of infection Very physically and psychologically grueling ProsCons

Magnetically Controlled Growing Rods (MCRG) Attached in basically the same way as the dual growing rods Lengthened during quick follow-ups in the office without any invasive surgery every 3-4 months This allows for the curve to be managed until their skeletal structure has matured enough for spinal fusion The EOS is then tracked using radiographs [6]

[7]

MCGR This technique is very new in the United States so not many hospitals are doing it The first one was completed in Washington DC on a ten year old boy The requirements are a skeletal age of 10 years old or younger and a Cobb angle of 50 degrees or greater Approved by the FDA in February of 2014

[8]

MCGR Experiment Criteria Younger than 11 years old Major curve of at least 30 degrees Radiographic thoracic height (T1-T12) less then 22cm No previous spine surgery 2 year follow-up The Experiment 12 MCGR patients 12 TGR patients All paired by gender number of rods, age, curve and type of EOS [6]

Results Major Curve Correction Very similar with MCGR and TRG patients Overall it was 32% and 33% Spinal Height(T1-S1) MCGR- 8.1mm/year TGR- 9.7mm/year This is not considered significantly different Throacic Height(T1-T12) MCGRTRG Height before surgery158mm166mm Height immediately following surgery186mm189mm Growth per year1.5mm/yr2.3mm/yr

Results MCRG 16 surgeries 137 noninvasive lengthenings 8 implant related complications TRG 73 surgeries 12 for initial implant 56 for lengthening 11/12 had complications 4 surgical site infection and 13 implant related NOTE: All of these patient were from different facilities so there could be some variations in results [6]

Discussion of Results MCGR-does not allow for the sagittal plane to contour ideally because of where the actuator has to be located TRG-May produce better results when solely looking at numbers but when the surgeries and many complications are added in it is not ideal It is possible that the MCRG would have had results even more similar or better than the TRG results had there been a longer follow up (average follow up for TR patients was 1.6 years longer)

References [1] "Congenital Scoliosis." - Scoliosis Research Society (SRS). N.p., n.d. Web. 22 Sept types of scoliosis [2] "Anatomy of the Spine." Spine Anatomy : Southern Oregon Neurosurgical & Spine Associates, PC. N.p., n.d. Web. 26 Sept [3] "MD Lingo." MD Lingo. N.p., n.d. Web. 26 Sept [4] Hershman, Staurt H., Justin J. Park, and Baron S. Lonner. "Fusionless Surgery for Scoliosis." Fusionless Surgery for Scoliosis (2013): n. pag. Web. 22 Sept [5] "Frequently Asked Questions." Growing Spine Foundation. N.p., n.d. Web. 22 Sept [6] Pawlek, Jeff B., and Growing Spine Study Group. "Traditional Growing Rods Versus Magnetically Controlled Growing Rods for the Surgical Treatment of Early-Onset Scoliosis: A Case- Matched 2-Year Study." 2.6 (2014): Web. [7] Controlled Growing Rods Treat Scoliosis in Children." MedGadget. N.p., n.d. Web. 22 Sept [8] Chueng, and Samartzis. "Management of EOS." N.p., n.d. Web.