Non-invasive assessment of muscle compartment elasticity by pressure related ultrasound in pediatric trauma: A prospective clinical study in twenty-five cases of forearm shaft fractures

Background: Soft tissue swelling after limb fractures in pediatric patients is well known to be a risk factor for developing acute compartment syndrome (ACS). Clinical assessment alone is uncertain in specific cases. Recently, we proposed a non-invasive ultrasound based method to objectify muscle compartment elasticity for monitoring. We hypothesize a strong correlation between the soft tissue swelling after stabilization of upper limb fractures and the compartment elasticity objectified with a novel ultrasound-based approach in pediatric trauma. Patients and Methods: In a prospective clinical study, children suffering forearm fractures but not developing an ACS were included. The muscle compartment elasticity of the m. flexor carpi ulnaris was assessed after surgical intervention by a novel non-invasive, ultrasound-based method resulting in a relative elasticity (RE in %) in both, the control (healthy limb) and study group (fractured limb). Soft tissue swelling was categorized in four different levels (0-3) and correlated with the resulting RE (%). Results: : The RE in the study group (15,67%, SD +/-3,06) showed a significantly decreased level (p<0,001) compared with the control (22,77%, SD +/- 5,4). The categorized grade of soft tissue swelling resulted in a moderate correlation with the RE (r s = 0,474). Conclusions: The presented study appears to represent a novel approach to assess the posttraumatic pressure changes in a muscle compartment after fracture stabilization non-invasively. In this first clinical study in pediatric cases, our measurement method represents a low cost, easy and secure approach that has the potential to substitute invasive measurement for monitoring muscle compartment conditions. Further investigations and development in lager cohorts are required to improve its daily clinical practicability and to confirm the expected reliability.