Ultrasound Imaging and Guidance in the Diagnosis and Hydrodissection of Superficial Radial Nerve Entrapment After Fracture Surgery

The Application of Ultrasound Guidance in Electrodiagnostic Studies - A Narrative Review

Electrodiagnostic studies, including nerve conduction study and electromyography, were conducted based on surface anatomy in a conventional manner. However, the anatomical variations and difficulty in the identification of target nerves or muscles render the accuracy of electrodiagnostic studies questionable. In recent years, high-resolution ultrasound (US) has been used to scan both the peripheral nerves and musculoskeletal system. Furthermore, an increasing number of clinicians have incorporated US into electrodiagnostic studies to achieve accurate sampling and prevent potential unwanted tissue injuries. In this review article, we present summarized information about the utility of US in assisting electrodiagnostic studies.

Ultrasound-Guided Hydrodissection Provides Complete Symptom Resolution in Radial Tunnel Syndrome: A Case Series and Scoping Review on Hydrodissection for Radial Nerve Pathology

ABSTRACT

This study analyzes the effectiveness of ultrasound-guided hydrodissection (HD) perineural as a treatment for radial tunnel syndrome (RTS). A literature search was performed along with retrospective analysis of local cases to assess outcomes and safety of this procedure. In the case series, surgical candidates, defined as cases with over 80% but temporary relief after diagnostic injection, were treated with ultrasound-guided HD. Of 22 patients who received ultrasound-guided diagnostic injections, 11 proceeded to HD. All HD patients experienced complete and lasting symptom resolution for a minimum of 2 years, and none required surgery. Thorough literature review provided seven studies, which fulfilled inclusion criteria. Sixty-one patients are represented in the literature. All studies reported significant benefit to pain symptoms with HD of radial nerve, with five specifying over 90% improvement. No adverse effects from HD were noted in any study. Ultrasound-guided HD of the radial tunnel has potential to be a surgery sparing treatment for RTS.

Efficacy of 5% Dextrose Water Injection for Peripheral Entrapment Neuropathy: A Narrative Review

Current non-surgical treatment for peripheral entrapment neuropathy is considered insignificant and unsustainable; thus, it is essential to find an alternative novel treatment. The technique of perineural injection therapy using 5% dextrose water has been progressively used to treat many peripheral entrapment neuropathies and has been proven to have outstanding effects in a few high-quality studies. Currently, the twentieth edition of Harrison’s Principles of Internal Medicine textbook recommends this novel injection therapy as an alternative local treatment for carpal tunnel syndrome (CTS). Hence, this novel approach has become the mainstream method for treating CTS, and other studies have revealed its clinical benefit for other peripheral entrapment neuropathies. In this narrative review, we aimed to provide an insight into this treatment method and summarize the current studies on cases of peripheral entrapment neuropathy treated by this method.

Ultrasound guidance may have advantages over landmark-based guidance for some nerve conduction studies

BACKGROUND

Precise placement of stimulating and recording electrodes is vital when performing nerve conduction studies (NCSs). In this study, we aimed to determine whether ultrasonography (US) was more precise in localizing the superficial radial nerve (SRN), dorsal ulnar cutaneous nerve (DUCN), ulnar nerve (UN) crossing the cubital tunnel, and radial nerve (RN) crossing the spiral groove (SG) compared to conventional techniques.

METHODS

Thirty healthy young subjects (15 male) were recruited. Each subject underwent both landmark-based and US-guided NCS. Onset latencies and amplitudes of compound motor action potentials (CMAPs) and sensory nerve action potentials (SNAPs), and stimulation levels (ie, intensity × duration) required to obtain maximal CMAP amplitudes were compared between the two techniques.

RESULTS

The mean CMAP amplitudes of the UN above the cubital tunnel (9.55 ± 1.96 vs 8.96 ± 1.94 mV, P = .030), UN below the cubital tunnel (10.11 ± 2.07 vs 9.37 ± 1.95 mV, P < .001), and RN below the SG (5.21 ± 1.56 vs 4.34 ± 1.03 mV, P < .001) were significantly greater using US-guided NCSs compared to landmark-based NCSs. The mean onset latency of the DUCN was significantly shorter using US-guided NCSs (1.49 ± 0.15 vs 1.57 ± 0.14 ms, P = .020). The required stimulation level in the UN and RN was significantly lower using US-guided NCSs.

CONCLUSIONS

When performing NCSs, US guidance provides a more precise localization of the stimulator and electrodes for the DUCN, UN, and RN, while providing comparable localization for the SRN, compared to landmark-based techniques.