Cost Analysis of Magnet-driven Growing Rods for Early-onset Scoliosis at 5 Years.

STUDY DESIGN: Prospective case series of nine children with early-onset scoliosis (EOS) treated by a single surgeon with a novel implant, the magnet-driven growing rod (MdGR) in a publicly funded health care service accounting for "payer costs" (PC) incurred. OBJECTIVE: The aim of this study was to compare the cost-effectiveness of MdGR versus conventional growing rods (CGRs) with respect to the PC incurred for treating EOS at 5 years. SUMMARY OF BACKGROUND DATA: Cost estimate and mathematical modeling study projections of MdGR have shown despite high insertional costs, it breaks even with CGR by 3 to 4 years. However, no clinical study to date exists either supporting or refuting this hypothesis. METHODS: Nine patients with EOS secondary to idiopathic (two), congenital (one), syndromic (three), and neuromuscular (three) etiologies treated by submuscular insertion of MdGR against stringent inclusion criteria formed the study cohort. We collected costs incurred with all aspects of care over the lifetime of device (or at least 5 years) from payers' perspective to compute and report average PC incurred per patient. We performed this cost analysis by comparing the MdGR PC against literature reported PC for CGR at 5 years. RESULTS: There were five single rod (SR) and two dual rod (DR) de novo MdGR insertions, while two patients had conversion of CGR to MdGR. MdGR alone accounted for at least 50% of overall budget. The MdGR was at least 40% more cost-effective in comparison to the CGR (£34,741 vs. £52,293) and there were seven MdGR graduates. CONCLUSION: The first study reporting direct PC incurred in EOS treated by MdGR that is devoid of any mathematical modeling and deterministic sensitivity analysis is presented. The true societal/human cost savings taking into consideration indirect costs are likely to be significantly higher. MdGR is a promising novel implant that may eventually become the "standard of care" for certain EOS etiologies. LEVEL OF EVIDENCE: 4.

Surgical results with the use of Silicated Calcium Phosphate (SiCaP) as bone graft substitute in Posterior Spinal Fusion (PSF) for Adolescent Idiopathic Scoliosis (AIS).

BACKGROUND: The gold standard iliac crest bone graft (ICBG) used to achieve arthrodesis in spinal fusions is not without complications (donor-site morbidity, iliac wing fractures etc.…). Our objectives were to evaluate the role of silicated calcium phosphate (SiCaP), an osteoconductive synthetic bone graft substitute in conjunction with locally harvested autologous bone in achieving arthrodesis following posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) and report clinic-radiological results / adverse events with its use in a prospective single surgeon case series (Level of evidence [LoE] IV) treated by low implant density index (IDI) constructs (i.e., IDI ≤1.5). METHODS: Thirty-five patients (8♂ & 2727♀) who underwent PSF and followed-up for a minimum of 2 years formed the study cohort. The mean age at surgery was 15 years (range: 11-21y) and pre-op Cobb angle was 60° (range: 40°-90°). SiCaP mixed with locally harvested bone during exposure and instrumentation was laid over instrumented segments. The average SiCaP used per patient was 32mls (range: 10-60mls). Radiographs were assessed for fusion at serial six monthly follow-ups. All clinical adverse events and complications were recorded. RESULTS: The mean follow-up was 2.94 years (range: 2-4y). The post-op Cobb angle improved to 23° (range: 2°- 55°) and the mean in-patient stay was 7.72 days (range: 5-13d). The mean number of instrumented segments was 9.4 (range: 4-13) and implant density index (IDI) averaged 1.23 (range: 1.15-1.5). Radiographic new bone formation was seen within 3 months in all cases. All patients (except two) were highly satisfied at minimum follow-up of 8 years. There were two complications warranting revision surgery (deep infection, and implant failure without any evidence of pseudarthrosis). There were no SiCaP specific adverse events in any of the 35 patients. CONCLUSION: SiCaP facilitated early bony consolidation in operated cohort of AIS patients treated by PSF. There were no inflammatory reaction or other adverse effects associated with its use. SiCaP is a safe alternative to autologous iliac crest bone graft with reduced complications, morbidity, faster recovery and similar infection/fusion rates reported in the literature.