Ultrasound assessment of selected peripheral nerve pathologies. Part III: Injuries and postoperative evaluation

Abstract

The previous articles of the series devoted to ultrasound diagnostics of peripheral nerves concerned the most common nerve pathologies, i.e. entrapment neuropathies. The aim of the last part of the series is to present ultrasound possibilities in the postoperative control of the peripheral nerves as well as in the diagnostics of the second most common neuropathies of peripheral nerves, i.e. posttraumatic lesions. Early diagnostics of posttraumatic changes is of fundamental importance for the course of treatment and its long-term effects. It aids surgeons in making treatment decisions (whether surgical or conservative). When surgical treatment is necessary, the surgeon, based on US findings, is able to plan a given type of operative method. In certain cases, may even abandon the corrective or reconstructive surgery of the nerve trunk (when there are extensive defects of the nerve trunks) and instead, proceed with muscle transfers. Medical literature proposes a range of divisions of the kinds of peripheral nerve injuries depending on, among others, the mechanism or degree of damage. However, the most important issue in the surgeon-diagnostician communication is a detailed description of stumps of the nerve trunks, their distance and location. In the postoperative period, ultrasound is used for monitoring the operative or conservative treatment effects including the determination of the causes of a persistent or recurrent neuropathy. It facilitates decision-making concerning a repeated surgical procedure or assuming a wait-and-see attitude. It is a difficult task for a diagnostician and it requires experience, close cooperation with a clinician and knowledge concerning surgical techniques. Apart from a static assessment, a dynamic assessment of possible adhesions constitutes a crucial element of postoperative examination. This feature distinguishes ultrasound scanning from other methods used in the diagnostics of peripheral neuropathies.

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

“…Thus, the learning curve for radiologists in the area of nerve sonography is considered steeper than, for example, via MRI [16]. While correct and timely diagnosis is essential for a patient's outcome [17,18], especially correct location identification can be time-consuming if following the nerves from a proximal segment, particularly if proximal segments of a given nerve cannot be visualized due to masking or lack of ultrasound penetration. Therefore, the relation of nerves and landmarks can be used for quicker identification of small nerve branches [19].…”

“…Thus, a correlation between clinical presentation and sonomorphologic alterations is possible [20]. HRUS enables differentiation between neurapraxia/axonotmesis on the one hand and neurotmesis, i. e. complete discontinuity of the nerve on the other [17,18,20]. Rapid diagnosis and treatment are essential especially in posttraumatic or iatrogenic nerve lesions [16].…”

“…Rapid diagnosis and treatment are essential especially in posttraumatic or iatrogenic nerve lesions [16]. Outcome rapidly worsens if delays occur in this early stage of nerve trauma [17,18]. Furthermore, HRUS can yield (preliminary) information on the nerve route, normal variants, the extent of the discontinuity and whether a graft will be needed [18].…”

Wrist ultrasound examination – scanning technique and ultrasound anatomy. Part 1: Dorsal wrist

“…The examination is equally frequently conducted in patients with pain or swelling of the wrist due to non-rheumatological causes. The symptoms can result from the presence of ganglion cysts, posttraumatic lesions of tendons and joints or the ligament complex, neuropathies of various nature and even tumors ( 19 – 22 ) .…”

Zmiany patologiczne ręki w badaniu ultrasonograficznym

“…In cases of nerve discontinuity the level of the stumps should be reported ( fig. 20 ) ( 18 ) . US has a very important role in treatment planning.…”