# Evaluation of Emerging Technologies to Aid in the Detection and Diagnosis of Acute Extremity Compartment Syndrome

## TL;DR

This study tests two devices for diagnosing acute compartment syndrome in pigs, finding one accurate and the other ineffective.

## Contribution

The study evaluates the MY01® and Moxy Monitor in a preclinical model for diagnosing acute compartment syndrome.

## Key findings

- The MY01® provided accurate ICP measurements with strong correlation to reference probes.
- The Moxy Monitor failed to detect significant SmO2 differences between injured and control limbs.
- The preclinical model effectively simulated and sustained elevated ICP for 24 hours.

## Abstract

Background/Objectives: The diagnosis of acute compartment syndrome (ACS) of the extremities is typically based on subjective clinical signs and symptoms, highlighting the need for user-friendly diagnostic tools to improve accuracy and reliability. This study evaluates the performance of two commercial devices, the MY01® continuous pressure monitoring system and the Moxy Monitor near-infrared spectroscopy-based system, against a reference standard of continuous intracompartmental pressure (ICP) monitoring in a preclinical ACS model. Methods: ACS was induced in the anterior compartment of the distal hind limb in eight Yorkshire pigs using a balloon displacement model. ICP was incrementally elevated and maintained for four hours at >30 mmHg above mean arterial pressure. This was followed by balloon deflation and reperfusion. Final assessments were performed at 24 h post-injury. ICP measurements from the MY01® and muscle oxygen saturation (SmO2) data from the Moxy Monitor were compared to reference ICP measurements. Histologic analysis of muscle tissue was performed to assess the severity of necrosis. Results: The MY01® provided accurate ICP measurements, with a mean bias of 2.21 ± 18.77 mmHg during pre-ischemia, 4.86 ± 10.43 mmHg during reperfusion, and 4.69 ± 3.28 mmHg 24 h post-injury, compared to reference probes. Correlation at 24 h post-injury was (r = 0.86, R2 = 0.73, p < 0.0001). In contrast, the Moxy Monitor failed to detect significant differences in SmO2 between injured and control limbs at 24 h post-injury, despite pronounced ICP differences. Our volumetric displacement ACS model demonstrated its efficacy as a testing platform by allowing for controlled, incremental elevation in ICP and sustaining elevated ICP levels after 24 h. Histologic evaluation confirmed extensive muscle damage, including edema and necrosis. Conclusions: The MY01® provides accurate, continuous ICP monitoring, supporting its clinical utility in ACS diagnosis. However, the use of near-infrared spectroscopy-based systems such as the Moxy Monitor for ACS diagnosis and management should continue to be critically scrutinized.