Feasibility of Ultrasound Measurements of Peripheral Sensory Nerves in Head and Neck Area in Healthy Subjects

Background: Current diagnostic methods for nerve compression headaches consist of diagnostic nerve blocks. A less-invasive method that can possibly aid in the diagnosis is ultrasound, by measuring the cross-sectional area (CSA) of the affected nerve. However, this technique has not been validated, and articles evaluating CSA measurements in the asymptomatic population are missing in the current literature. Therefore, the aim of this study was to determine the feasibility of ultrasound measurements of peripheral extracranial nerves in the head and neck area in asymptomatic individuals.Methods: The sensory nerves of the head and neck in healthy individuals were imaged by ultrasound. The CSA was measured at anatomical determined measurement sites for each nerve. To determine the feasibility of ultrasound measurements, the interrater reliability and the intrarater reliability were determined.Results: In total, 60 healthy volunteers were included. We were able to image the nerves at nine of 11 measurement sites. The mean CSA of the frontal nerves ranged between 0.80 ± 0.42 mm2 and 1.20 ± 0.43 mm2, the mean CSA of the occipital nerves ranged between 2.90 ± 2.73 mm2 and 3.40 ± 1.91 mm2, and the mean CSA of the temporal nerves ranged between 0.92 ± 0.26 mm2 and 1.40 ± 1.11 mm2. The intrarater and interrater reliability of the CSA measurements was good (ICC: 0.75–0.78).Conclusions: Ultrasound is a feasible method to evaluate CSA measurements of peripheral extracranial nerves in the head and neck area. Further research should be done to evaluate the use of ultrasound as a diagnostic tool for nerve compression headache

Spatiotemporal dynamics of re-innervation and hyperinnervation patterns by uninjured CGRP fibers in the rat foot sole epidermis after nerve injury

The epidermis is innervated by fine nerve endings that are important in mediating nociceptive stimuli. However, their precise role in neuropathic pain is still controversial. Here, we have studied the role of epidermal peptidergic nociceptive fibers that are located adjacent to injured fibers in a rat model of neuropathic pain. Using the Spared Nerve Injury (SNI) model, which involves complete transections of the tibial and common peroneal nerve while sparing the sural and saphenous branches, mechanical hypersensitivity was induced of the uninjured lateral (sural) and medial (saphenous) area of the foot sole. At different time points, a complete foot sole biopsy was taken from the injured paw and processed for Calcitonin Gene-Related Peptide (CGRP) immunohistochemistry. Subsequently, a novel 2D-reconstruction model depicting the density of CGRP fibers was made to evaluate the course of denervation and re-innervation by uninjured CGRP fibers. The results show an increased density of uninjured CGRP-IR epidermal fibers on the lateral and medial side after a SNI procedure at 5 and 10 weeks. Furthermore, although in control animals the density of epidermal CGRP-IR fibers in the footpads was lower compared to the surrounding skin of the foot, 10 weeks after the SNI procedure, the initially denervated footpads displayed a hyper-innervation. These data support the idea that uninjured fibers may play a considerable role in development and maintenance of neuropathic pain and that it is important to take larger biopsies to test the relationship between innervation of injured and uninjured nerve areas

Routinely-Collected Outcomes of Proximal Row Carpectomy.

PURPOSE: To describe patient-reported pain and function 12 months after proximal row carpectomy (PRC). Secondary outcomes included return to work, grip strength, range of wrist motion, satisfaction with treatment results, and complications. METHODS: This cohort study was part of the British Society for Surgery of the Hand Studyathon 2021, using ongoing routinely-collected data of 304 eligible patients who underwent PRC (73% scapholunate advanced collapse, 11% scaphoid nonunion advanced collapse wrist; 11% Kienböck, 5% other indications) from Xpert Clinics, the Netherlands between 2012-2020. The primary outcome was the Patient Rated Wrist/Hand Evaluation total score (range, 0-100, lower scores indicate better performance). RESULTS: Of the 304 patients, the primary outcome was available in 217 patients. The total Patient Rated Wrist/Hand Evaluation score improved from 60 (95% confidence interval [CI], 57-63) to 38 (95% CI, 35-41) at 3 months, and 26 (95% CI, 23-29) at 12 months. The pain and function subscales improved by 18 (95% CI, 17-20) and 16 (95% CI, 14-18) points, respectively. At 12 months, 82% had returned to work at a median time of 12 (95% CI, 9-14) weeks following PRC. Grip strength did not improve. Wrist flexion and extension demonstrated a clinically irrelevant decrease. Satisfaction with treatment result was excellent in 27% of patients, good in 42%, fair in 20%, moderate in 6%, and poor in 5%. Complications occurred in 11% of patients, and conversion to wrist arthroplasty occurred in 2 patients. CONCLUSION: A clinically relevant improvement in patient-reported pain and function was observed at 3 months after PRC, with continued improvement to 12 months. These data can be used for shared-decision making and expectation management. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV