Growth-Friendly Implant [Neurosurgery Wiki]

This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.
===== Growth-Friendly Implant =====
A '''growth-friendly implant''' is a temporary spinal device used in the management of '''early-onset scoliosis (EOS)''' that permits continued spinal and thoracic growth while controlling deformity. Unlike definitive spinal fusion, these systems aim to stabilize curvature without halting skeletal development.

==== Key Characteristics ====
  * Designed for '''children with immature spines'''
  * Allows for '''incremental lengthening''' over time
  * Intended for use '''prior to final spinal fusion'''
  * Helps preserve '''lung development and height potential'''

==== Common Types ====
  * Traditional Growing Rods (TGR)
  * Magnetically Controlled Growing Rods (MCGR, e.g., MAGEC)
  * Vertical Expandable Prosthetic Titanium Rib (VEPTR)
  * Shilla Growth Guidance System

==== Clinical Goal ====
To control progressive spinal curvature in EOS while maintaining spine and thoracic growth, delaying or avoiding early definitive fusion.

===== Comparative cohort studies =====

In a [[registry]]-based [[comparative]] [[cohort study]] ([[early onset scoliosis]] patients after [[implant]] [[removal]])
Matan S Malka et al.
from the Morgan Stanley Children’s Hospital (Columbia Univ, New York).
Arkansas Children’s Hospital; Shriners Philadelphia; Seattle Children’s Hosp.
published in [[Spine Deformity Journal]],
to evaluate if re-implanting growth-friendly constructs within 12 months after implant removal (ROI) stabilizes deformity compared to [[observation]]-only.
Early re-implantation (< 12 mo post-ROI) significantly reduces 2‑year coronal [[Cobb]] progression compared to no replacement
((Malka MS, Lenke LG, Givens RR, Lu K, Rymond CC, McCarthy R, Samdani AF, Yaszay B, Pahys J, Vitale MG, Roye BD, Group PSS. [[Failure]] to replace removed [[growth friendly implant]]s results in deteriorating radiographic outcomes. Spine Deform. 2025 Jul 4. doi: 10.1007/s43390-025-01137-5. Epub ahead of print. PMID: 40613981.)).


====== Critical Review ======

- **Strengths**:  

[[Multicenter]] registry with well-defined exposure groups.  

Radiographic outcomes measured at a meaningful 2‑year follow-up.  

Statistically robust with p-values: Cobb 81° vs 53° (p=0.003); progression ≥5°: 64% vs 30% (p=0.04) 

- **Limitations**:  

Small observation cohort (n=11) limits [[generalizability]].  

Indications for ROI and patient selection unclear—could [[bias]] results.  

Lack of data on [[functional outcome]]s or complications post re-implantation.  

Does not assess long-term outcomes past 2 years or final fusion timing.

====== Score (0–10) ======

5.5  

(Moderate quality; clinically relevant, but underpowered and limited in scope)

====== Takeaway for Practicing Neurosurgeons ======

Prompt re-implantation after growth‑friendly device removal appears crucial to arrest deteriorating curves in EOS. However, decision-making should be individualized, considering technical feasibility and patient comorbidities.

====== Bottom Line ======

Re-inserting a growth-friendly implant within 12 months of removal significantly reduces coronal curve progression over 2 years and should be prioritized when feasible—though data are limited by small control group and absence of long-term outcomes.

==== Full Citation and Corresponding Author ====

**Published online:** July 4, 2025  
**Corresponding author:** [[msm2244@cumc.columbia.edu]].