# External hinged fixation vs. internal joint stabilization for elbow instability: a systematic review and meta-analysis of functional outcomes and surgical complications

## TL;DR

This study compares two treatments for elbow instability and finds that hinged external fixation leads to better functional outcomes than internal joint stabilization.

## Contribution

The study provides a systematic review and meta-analysis comparing functional outcomes and complications of HEF and IJS for elbow instability.

## Key findings

- HEF showed significantly better Disabilities of the Arm, Shoulder, and Hand scores than IJS.
- No significant differences were found in postoperative range of motion or nerve injury rates between the two treatments.
- The study highlights the need for future research with standardized protocols and longer follow-up.

## Abstract

Traumatic elbow instability can be managed with hinged external fixator (HEF) or internal joint stabilizer (IJS). While prior studies report device-related complications with both devices, a comprehensive analysis comparing range of motion (ROM), patient-reported outcome measures, and surgical complications is limited. This study aims to evaluate these outcomes to guide treatment decisions for complex elbow instability.

This systematic review and meta-analysis was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A comprehensive search was performed in Google Scholar and PubMed from January 1, 2000, to February 20, 2025. Level I-IV studies were included if they reported on postoperative ROM, patient-reported outcome measure, or surgical complications as outcome measures in patients treated with HEF or IJS for elbow instability.

Of the 2,041 articles identified, 38 studies met inclusion criteria for quantitative synthesis, including 27 of moderate quality and 11 of high quality based on the Newcastle–Ottawa Scale classification. Across the 29 retrospective studies, 8 prospective studies, and 1 randomized control trial, 500 patients underwent treatment with HEF, while 263 patients were treated with IJS. Disabilities of the Arm, Shoulder, and Hand scores were significantly better in the HEF group compared to IJS (9.8 vs. 23; P < .001). No significant differences were found between HEF and IJS in postoperative ROM, Mayo Elbow Performance Index, visual analog scale for pain, heterotopic ossification, or nerve injury rates.

HEF and IJS showed comparable rates of postoperative ROM, Mayo Elbow Performance Index, visual analog scale, heterotopic ossification, and nerve injury. However, Disabilities of the Arm, Shoulder, and Hand scores were 13.2 points lower in the HEF group, exceeding the minimal clinically important difference of 10.8 and indicating a clinically meaningful functional advantage of the upper extremity. This difference may be influenced by the less invasive nature of hardware removal with HEF compared to IJS. These findings should be interpreted with caution, given the overall lower level of evidence and heterogeneity across studies. Future prospective investigations with standardized rehabilitation protocols, longer follow-up, and stratification by injury chronicity, limb dominance, and preoperative motion are needed to better define optimal indications for each technique.