# Impact of Intramedullary Implants on Metallic Element Homeostasis in Children with Forearm Fractures

## TL;DR

This study examines how intramedullary implants affect metal levels in children with forearm fractures, finding minimal systemic impact except for a slight rise in blood titanium.

## Contribution

The study provides new evidence on the safety of titanium intramedullary implants in children regarding systemic metal ion release.

## Key findings

- No significant systemic changes in calcium, magnesium, copper, zinc, or aluminum were observed.
- A modest but significant increase in blood titanium levels was found after treatment, especially in patients with two rods.
- Multivariate analysis confirmed the stability of elemental profiles, with titanium being the main contributor to post-treatment variation.

## Abstract

Background/Objectives: Childhood is marked by frequent musculoskeletal injuries, with fractures representing a major cause of pediatric trauma admissions. Unstable long-bone fractures often require surgical stabilization, commonly achieved using elastic stable intramedullary nailing (ESIN). Although this method ensures effective fixation and early mobilization, concerns remain regarding potential metal ion release in growing children. This study aimed to assess changes in calcium, magnesium, copper, zinc, titanium, and aluminum concentrations in blood and material from the medullary cavity of forearm fractures following intramedullary fixation. Methods: A prospective study was conducted on 40 patients aged 4–15 years treated with ESIN at the University Children’s Hospital in Lublin. Peripheral blood and material from the medullary cavity were collected before implantation and at implant removal. Elemental concentrations were determined using high-resolution ICP-OES, and statistical analyses included paired comparisons, delta values, and multivariate methods. Results: No significant systemic changes were found for calcium, magnesium, copper, zinc, or aluminum. A modest but significant increase in blood titanium levels was observed after treatment (p = 0.0075), especially in patients with two rods. Multivariate analysis confirmed overall stability of elemental profiles, with titanium contributing most strongly to post-treatment variation. Conclusions: Intramedullary titanium fixation in children does not significantly disrupt systemic mineral homeostasis. The slight increase in circulating titanium reflects implant exposure rather than toxicity, supporting the safety of ESIN, although continued monitoring of metallic elements may be warranted.