Measuring intracompartmental pressures for the chronic exertional compartment syndrome: challenging commercially available devices and their respective accuracy

Ultrasound guided compressibility of the lower leg anterior tibial muscle compartment: a feasibility study

OBJECTIVES

Some young individuals participating in sports activities may encounter lower leg muscle pain and tightness, potentially indicating chronic exertional compartment syndrome (CECS). While muscle pressure measurement is typically recommended for diagnosis, it is invasive and associated with low sensitivity and specificity. Thus, there is a need for novel diagnostic approaches.

METHODS

This feasibility study aims to assess whether an ultrasound-guided technique can effectively measure the compressibility of the anterior tibial muscle compartment, focusing on optimal leg positioning and identifying reliable external and internal anatomical landmarks. The compressibility of the anterior tibial muscle compartment was evaluated using ultrasound images obtained at 10 mmHg and 80 mmHg external pressure, with the drop in compartment thickness used to calculate the compressibility ratio. Measurements were conducted in various leg positions and utilizing different external and internal landmarks.

RESULTS

Studies in healthy volunteers showed that knee and heel support positioning, measuring at the leg's widest circumference, and using the interosseous membrane as an internal landmark yielded the lowest measurement variability with an intra class correlation of .977 (.764-1.000; 95%-confidence interval).

CONCLUSION

These findings suggest that ultrasound-guided techniques can feasibly determine the compressibility ratio of the anterior tibial muscle compartment, providing valuable insights for standardized protocols in future studies on suspected cases of chronic exertional compartment syndrome.

Elevated fluid and glycosaminoglycan content in the Achilles tendon contribute to higher intratendinous pressures: Implications for Achilles tendinopathy

BACKGROUND

Tendinopathy alters the compositional properties of the Achilles tendon by increasing fluid and glycosaminoglycan content. It has been speculated that these changes may affect intratendinous pressure, but the extent of this relationship remains unclear. Therefore, we aimed to investigate the impact of elevated fluid and glycosaminoglycan content on Achilles tendon intratendinous pressure and to determine whether hyaluronidase (HYAL) therapy can intervene in this potential relationship.

METHODS

Twenty paired fresh-frozen cadaveric Achilles tendons were mounted in a tensile-testing machine and loaded up to 5% strain. Intratendinous resting (at 0% strain) and dynamic pressure (at 5% strain) were assessed using the microcapillary infusion technique. First, intratendinous pressure was measured under native conditions before and after infusion of 2 mL physiological saline. Next, 80 mg of glycosaminoglycans were administered bilaterally to the paired tendons. The right tendons were additionally treated with 1500 units of HYAL. Finally, both groups were retested, and the glycosaminoglycan content was analyzed.

RESULTS

It was found that both elevated fluid and glycosaminoglycan content resulted in higher intratendinous resting and dynamic pressures (p < 0.001). HYAL treatment induced a 2.3-fold reduction in glycosaminoglycan content (p = 0.002) and restored intratendinous pressures.

CONCLUSION

The results of this study demonstrated that elevated fluid and glycosaminoglycan content in Achilles tendinopathy contribute to increased intratendinous resting and dynamic pressures, which can be explained by the associated increased volume and reduced permeability of the tendon matrix, respectively. HYAL degrades glycosaminoglycans sufficiently to lower intratendinous pressures and may, therefore, serve as a promising treatment.

Practical Review on the Contemporary Diagnosis and Management of Compartment Syndrome

Acute compartment syndrome (ACS) is a limb-threatening pathology that necessitates early detection and management. The diagnosis of ACS is often made by physical examination alone; however, supplemental methods such as compartment pressure measurement, infrared spectroscopy, and ultrasound can provide additional information that support decision-making. This practical review aims to incorporate and summarize recent studies to provide evidence-based approaches to compartment syndrome for both resource-rich and -poor settings among several patient populations.

Applicability of devices available for the measurement of intracompartmental pressures: a cadaver study

Purpose

The indication for surgical treatment of the chronic exertional compartment syndrome is evaluated by measuring intracompartmental pressures. The validity of these invasive intracompartmental pressure measurements are increasingly questioned in the absence of a standardized test protocol and uniform cut-off values. The aim of the current study was to test compartment pressure monitors and needles for uniformity, thereby supporting the physician’s choice in the selection of appropriate test materials.

Methods

A compartment syndrome was simulated in embalmed above-knee cadaveric leg specimen. Four different terminal devices (Compass manometer, Stryker device, Meritrans transduce, and arterial line) were tested with 22 different needle types. Legs were pressurized after introduction of the four terminal devices in the anterior compartment, using the same needle type. Pressure was recorded at a 30-second interval for 11 minutes in total. Before and after pressurization, the intravenous bag of saline was weighed.

Results

The simulation of a compartment syndrome resulted in intracompartmental pressure values exceeding 100 mmHg in 17 of the 22 legs (77%). In the other five legs, a smaller built-up of pressure was seen, although maximum intracompartmental pressure was in between 70 and 100 mmHg. The intraclass correlation coefficient was above 0.700 for all possible needle types. Excellent to good resemblance was seen in 16 out of 22 instrumental setups (73%). The mean volume of saline infusion required in runs that exceeded 100 mmHg (309 ± 116 ml) was significantly lower compared to the legs in which 100 mmHg was not achieved (451 ± 148 ml; p = 0.04).

Conclusion

The intracompartmental pressure recordings of the four terminal devices were comparable, when tested with a standardized pressurization model in a human cadaver model. None of the included terminal devices or needle types were found to be superior. The results provide evidence for more diverse material selection when logistic choices for intracompartmental pressure measurement devices are warranted.

Level of evidence

Level IV.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40634-022-00529-0.