Ultrasonography of the Peripheral Nerves of the Forearm, Wrist and Hand: Definition of Landmarks, Anatomical Correlation and Clinical Implications

Correlation of In-situ Hand Anatomy With Point of Care Ultrasound

The effective use of point-of-care ultrasound for the diagnosis and treatment of hand conditions is dependent upon a thorough understanding of its anatomic bases. To facilitate this understanding, in-situ cadaveric hand dissections were correlated with handheld ultrasound images in the palm focusing on key areas of clinical relevance. The palms of an embalmed cadaver were dissected, minimizing the reflection of structures whenever possible to emphasize normal relationships and tissue planes. Point-of-care ultrasound images were obtained from a living hand and correlated with related anatomy in the cadaver. Juxtaposing cadaver structures, spaces, and relationships with the associated ultrasound images, surface hand orientation, and ultrasound probe positioning, a series of images were developed as a guide to correlating in-situ anatomy with point-of-care ultrasound in the hand.

Ultrasound of the Hook of Hamate Region: Pictorial Review

The hook of hamate is a complex anatomical region with many small but important structures. A sound knowledge of anatomy along with a systematic ultrasound technique can help delineate a variety of disorders. In this pictorial review, we discuss the ultrasound anatomy and the possible pathologies that can be encountered in this region.

Ultrasound of Small Nerves

Nerve ultrasound has become an integral part of the diagnostic workup of peripheral neuropathies. Especially in the examination of small nerves, ultrasound provides superior image quality by using high frequency transducers. For a selection of small nerves, this article summarizes the local anatomy and common pathologies and offers simple instructions for determining their location with ultrasound including some cases with pathologies. This selection of nerves comprises the great auricular nerve, the supraclavicular nerves, the suprascapular nerve, the medial antebrachial cutaneous nerve, the lateral antebrachial cutaneous nerve, the palmar cutaneous branch of the median nerve, the long thoracic nerve, the intercostobrachial nerve, the posterior cutaneous nerve, the infrapatellar branch of the saphenous nerve, the medial calcaneal nerve, and the deep peroneal nerve at the ankle. Following our recommendations, these nerves can be swiftly located and tracked along their course to the site of the pathology.

Anatomy of the nerves, vessels, and muscular compartments of the forearm, as revealed by high-resolution ultrasound. Part 1: overall structure and forearm compartments

In recent decades, high-resolution ultrasound (HRUS) has revolutionized the morphological and structural evaluation of peripheral nerves and muscles, revealing details of the internal structure of the neural fascicles and muscle architecture. Applications range from diagnostics to interventional procedures. The anatomy of the forearm region is complex, with several muscles and an extensive network of vessels and nerves. To guarantee the success of the evaluation by HRUS, knowledge of the normal anatomy of the region is essential. The aim of these two companion articles is to present the normal anatomy of the nerves and compartments of the forearm, as revealed by HRUS, as well as the relationships between the main vessels and nerves of the region. Part 1 aims to review the overall structure of nerves, muscles and tendons, as seen on HRUS, and that of the forearm compartments. We present a practical approach, with general guidelines and tips on how best to perform the study. Part 2 is a pictorial essay about compartment vascularization and cutaneous innervation. Knowledge of the normal anatomy of the forearm improves the technical quality of the examinations, contributing to better diagnoses, as well as improving the performance and safety of interventional procedures.

Cutaneous nerve-conscious surgical repair of vascular access-related aneurysm assisted by anatomical ultrasonography in hemodialysis patients

BACKGROUND

The superficial runoff veins anatomically run alongside the cutaneous nerves in the volar forearm. Consequently, the surgical repair of vascular access (VA)-associated venous aneurysms attached to the cutaneous nerves could cause intraoperative nerve injury. Therefore, we proposed a cutaneous nerve-conscious VA-related aneurysmal repair assisted by nerve ultrasonography. This ultrasonography aids in the preoperative examination of the courses of the nerves neighboring the aneurysm.

METHODS

Sixteen consecutive patients who underwent surgical revisions of VA-related aneurysms (14 venous aneurysms and two arterial pseudoaneurysms) were enrolled. The locations of aneurysms derived from preexisting arteriovenous fistulas included 11 radiocephalic arteriovenous fistulas in the wrist or distally, three radiocephalic arteriovenous fistulas at the antecubital fossa, and two brachiocephalic arteriovenous fistulas at the antecubital fossa or in the distal upper arm. A preoperative ultrasonographic scan of the cutaneous nerve trunks that ran peripherally toward and along the aneurysms was attempted to avoid nerve injuries during operations. Basically, the aneurysms were resected from the proximal to the distal ends after being separated from the preserved adjacent nerves.

RESULTS

The cutaneous nerve trunks that coursed toward and along the aneurysm could be identified by preoperative ultrasonography and could be preserved intraoperatively based on ultrasonographic findings in all patients. In four patients, the cutaneous nerve branch was unexpectedly or intentionally severed for a seamless surgical process because the nerve branch that divided from the cutaneous nerve trunk was strongly attached to the aneurysm. They subsequently suffered from hypoesthesia, but did not experience neuropathic pain.

CONCLUSION

Preoperative ultrasonographic examination of the cutaneous nerve facilitated the intraoperative prevention of cutaneous nerve injury in VA-related aneurysmectomy. Nerve-sparing VA surgery assisted by preoperative nerve ultrasonography based on the understanding of topological anatomy might contribute to the reduction in postoperative neuropathy and enhance comfort in the daily life of hemodialysis patients.