Acute Compartment Syndrome (ACS) is an orthopaedic emergency that can develop after a wide array of etiologies. In this pilot study the MY01 device was used to assess its ease of use and its ability to continuously reflect the intracompartmental pressure (ICP) and transmit this data to a mobile device in real time. This preliminary data is from the lead site which is presently expanding data collection to five other sites as part of a multi-center study. Patients with long bone trauma of the lower or upper extremity posing a possibility of developing compartment syndrome were enrolled in the study. Informed consent was obtained from the patients. A Health Canada licensed continuous compartmental pressure monitor (MY01) was used to measure ICP. The device was inserted in the compartment that was deemed most likely to develop ACS and ICP was continuously measured for up to 18 hours. Fractures were classified according to the AO/OTA classification. Patient clinical signs and pain levels were recorded by healthcare staff during routine in-patient monitoring and were compared to the ICP from the device. Important treatment information was pulled from the patient's chart to help correlate all of the patient's data and symptoms. The study period was conducted from November 2020 through December 2021. Twenty-six patients were enrolled. There were 17 males, and nine females. The mean age was 38 years (range, 17–76). Seventeen patients received the device post-operatively and nine received it pre-operatively. Preliminary results show that post-operative ICPs tend to be significantly higher than pre-operative ICPs but tend to trend downwards very quickly. The trend in this measurement appears to be more significant than absolute numbers which is a real change from the previous literature. One patient pre-operatively illustrated a steep trend upwards with minimal clinical symptoms but required compartment release at the time of surgery that exhibited no muscle necrosis. The trend in this patient was very steep and, as predicted, predated the clinical findings of compartment syndrome. This trend allows an early warning signal of the absolute pressure, to come, in the compartment that is being assessed by the device. Preliminary results suggest that this device is reliable and relatively easy to use within our institutions. In addition it suggests that intracompartmental pressures can be higher immediately post-op but lower rapidly when the patient does not develop ACS. These results are in line with current literature of the difference between pre and post-operative baselines and thresholds of ICP, but are much more striking, as continuous measurements have not been part of the data set in most of past studies. Further elucidation of the pressure thresholds and profiles are currently being studied in the ongoing larger multicenter study and will add to our understanding of the critical values. This data, plus the added value of continuous trends in the pressure, upwards or downwards, will aid in preventing muscle necrosis during our management of these difficult long bone fractures

The threshold for decompression in acute compartment syndrome is quoted as a pressure difference between the compartment and diastolic blood pressure of less than 30mmHg. This study reports the findings of continuous compartment pressure monitoring in children who underwent tibial osteotomies. In this prospective observational study, twenty seven children who underwent tibial osteotomies had anterior compartment pressures monitored using a transducer-tipped probe for a minimum of 72 hours following surgery. Pressure data were collected hourly together with evidence of clinical signs, symptoms and patterns of analgesic use. Patients were also reviewed for late sequelae of compartment syndrome. One case of compartment syndrome were encountered. Pressure differences (diastolic BP - compartment pressure) were found to vary widely, with many children exceeding the threshold for decompression but without manifesting other signs of compartment syndrome. Fasciotomies were not performed in view of the conflicting evidence and subsequent review confirmed the absence of late sequelae. In these children, low diastolic blood pressures were a common but normal feature. The prevalence of compartment syndrome was 3.7% (1/27). The positive predictive value of using the adult threshold was 7.1%; the negative predictive value was 100%. We conclude that the threshold for decompression as applied to adults is unsuitable for use in children inasmuch as a positive result would lead to a correct diagnosis in only 7.1% of children. A negative test is more useful in correctly excluding compartment syndrome in 100% of the children studied

Purpose. Compartment syndrome is a limb threatening condition. Prior research has been limited by an inability to assess functional and histologic changes in muscle over time. This study was designed to assess and quantify functional deficits and histologic changes following acute compartment syndrome of the lower limb in a novel rat model. Method. Twenty-three male Wistar rats were trained to perform an incentive-based standard task on an optical gait tracking system. Animals were then randomized to three groups: Control (n=4), Sham (n=4) and Compartment Syndrome (CS, n=15). Control and sham animals had no elevation of intracompartmental pressure, while CS animals had elevated intracompartmental pressure to 30mmHg for 180 minutes in the anterior compartment of the left hind limb using a saline infusion technique. Following intervention, gait analysis was performed at 2hrs, 24hrs, 48hrs, 72hrs and 7days following injury. Several parameters for the injured hind limb were analyzed including: print area, print intensity, maximum contact timing, duty cycle and stance phase time. A 2-way ANOVA with Bonferroni post-hoc analysis was performed. The EDL muscle was harvested (n=17), fixed in formalin and prepared with an H&E stain. Mid-muscle sections were analyzed by a blinded senior pathologist for cell infiltration, necrosis and regeneration. Results. Function Changes: Mean print intensity was 96.5518.7 at 48hrs for CS animals, compared to 145.538.2 in control animals and 144.9612.71 in sham animals (p<0.001). At the 2hrs, 24hrs, and 48hrs time intervals post injury the CS animals showed significant decreases in print width (p<0.001), maximum contact (p<0.001), mean print intensity (p<0.001) and stance phase (p<0.01). There were no significant differences between baseline and 72hr results for any gait parameter (p>0.05). Histologic Changes: Cellular infiltration was noted at 24hrs, peaked at 48hrs and was still present at 7 days to a lesser degree. Necrosis began as early as 24hrs post injury and also peaked by 48hrs and returned to baseline levels by 7days. Minor regenerative changes were identified as early as 24hrs however the majority of changes were identified at 7 days post-injury. Conclusion. Developing and evaluating animal models for the study of compartment syndrome is essential for better understanding the condition and testing new treatment modalities. Gait analysis was a reproducible means of assessing function after compartment syndrome. Animals demonstrated an antalgic gait pattern demonstrated by decreased stance phase, decreased print intensity, and increased print width, with recovery demonstrated by 72hrs post-injury. Defining the histologic changes such as necrosis, cellular infiltration and regeneration associated with compartment syndrome has allowed us to further understand the evolving pathology of compartment syndrome over time. This study facilitates the evaluation of functional and histologic testing for the evaluation of new therapeutic interventions