Compartments of the crural fascia: clinically relevant ultrasound, anatomical and histological findings

PURPOSE

Compartment syndrome is a surgical emergency that can occur in any part of the body and can cause cell necrosis when maintained over time. The resulting defects can affect the nerves, muscle cells, bone tissue, and other connective tissues inside the compartment, and fasciotomy has to be performed. The anatomical and histological characteristics of the leg make acute, chronic, and exertional compartment syndrome more likely in this limb. For these reasons, knowledge of the ultrasound, anatomical, and histological features of the crural fascia can help in the treatment of leg compartment syndrome.

METHODS

Twenty-one cryopreserved lower limbs from adult cadavers and from one 29-week-old fetus were obtained from the dissection room. They were examined by ultrasound and a subsequent anatomical dissection and microscopy to study the crural fascia and its relationship with the different muscles. Anthropometric measurements were taken of the distances from the head of the fibula and lateral malleolus to the origin of the tibialis anterior muscle in the crural fascia, the exit of the superficial fibular nerve, and the fascia covering the deep posterior muscles of the leg.

RESULTS

The crural fascia has very important clinical relationships, which can be identified by ultrasound, as the origin of the tibialis anterior muscle at 16.25 cm from the head of the fibula and the exit of the superficial fibular nerve that crosses this fascia at 21.25 cm from the head of the fibula. Furthermore, the presence of a septum that fixes the deep posterior muscles of the leg and the vessels and nerve can be seen by ultrasound and can explain the possible development of a posterior compartmental syndrome of the leg. Awareness of these features will help to keep these structures safe during the surgical treatment of compartment syndrome.

CONCLUSION

The ultrasound study allows identification of anatomical structures in the leg and, thus, avoids damage to them during surgery for compartmental syndromes.

Compartments of the antebrachial fascia of the forearm: clinically relevant ultrasound, anatomical and histological findings

PURPOSE

Acute compartment syndrome is defined as a limb-threatening condition caused by bleeding or oedema in a closed muscle compartment surrounded by fascia or bone. It is most commonly encountered in the forearm, which has three compartments: posterior, anterior and lateral. These are surrounded and closed in by the antebrachial fascia, formed by dense connective tissue that facilities their study on ultrasound and is key to fasciotomy treatment. The purpose of this study was to broaden existing ultrasound, anatomical and histological knowledge of the fascia of the forearm to facilitate their identification on ultrasound, with possible clinical and therapeutic applications.

METHODS

The study was performed in 50 cryopreserved upper limbs from adult cadavers from the dissection room of the Faculty of Medicine and Health Sciences. They were examined on ultrasound and subsequent anatomical dissection and microscopy to study the fascia and its relationship with different muscles of the forearm compartments.

RESULTS

Distinct anatomical relationships were observed on ultrasound and dissection between the fascia and the extensor carpi ulnaris, extensor digiti minimi, and anconeus muscle in the posterior compartment, and the flexor carpi radialis and flexor carpi ulnaris in the anterior compartment. They were isolated by the antebrachial fascia and had distinct relationships with the neurovascular structures.

CONCLUSION

These results demonstrate that high-definition ultrasound enables us to locate the antebrachial fascia and particular muscles with a distinct relationship with neurovascular structures. This helps better identify these structures, facilitating diagnosis of any pathology in the area, with potential therapeutic and clinical applications.