Ultrasonographic measurement of the cross-sectional area of the axillary nerve.

INTRODUCTION: The objectives of this study were to determine normal reference values for ultrasonographic measurement of the cross-sectional area (CSA) of the axillary nerve and to standardize the measurement methods. METHODS: Sixty healthy volunteers were evaluated. Ultrasonography was performed with the shoulder positioned in 100°-120° abduction and 90° external rotation. The CSA of the axillary nerve was measured bilaterally. RESULTS: The normal CSA of the right axillary nerve was 2.9 ± 1.1 mm2 . The side-to-side discrepancy was 22.8% ± 17.8%. DISCUSSION: These reference values may be helpful for investigating pathologies involving the axillary nerve.

Approach for needle insertion into the tibialis posterior: An ultrasonography study.

INTRODUCTION: To avoid neurovascular damage by needle electrode insertion into the tibialis posterior, we used ultrasonography to determine the proper insertion point based on anatomic landmarks. METHODS: Using ultrasonography, the safety window, the corrected safety window, and the depth of the tibialis posterior were measured at 4 points (the upper third and midpoint of the tibia using anterior and posterior approaches) in healthy volunteers. RESULTS: The safety window at the midpoint for the posterior approach was significantly larger than at the other points. The corrected safety window could be defined only at the upper third for the anterior approach and at the midpoint for the posterior approach. CONCLUSIONS: Among the 4 points used for needle insertion into the tibialis posterior, the midpoint by the posterior approach may be the most favorable insertion point. The upper third may be better for the anterior approach.

Effect of Carpal Tunnel Syndrome on the Ulnar Nerve at the Wrist: Sonographic and Electrophysiologic Studies.

OBJECTIVES: The aim of this study was to compare the ulnar nerve at the wrist by sonographic and electrophysiologic studies between patients with carpal tunnel syndrome and control participants and to verify the effect of carpal tunnel syndrome of the ulnar nerve at the wrist. METHODS: Forty-two hands of patients with carpal tunnel syndrome and 37 hands of control participants were examined. Electrophysiologic studies of the ulnar nerve were done in all participants. The cross-sectional areas of the median and ulnar nerves at the wrist were evaluated by sonography. Fifteen hands of patients with carpal tunnel syndrome who underwent carpal tunnel release were also evaluated by sonography after the operation. RESULTS: The ulnar nerve cross-sectional area of the patients with carpal tunnel syndrome (mean ± SD, 5.16 ± 1.04 mm(2)) was significantly larger than that of the controls (3.56 ± 0.52 mm(2); P < .0001). After release of the transverse carpal ligament, the cross-sectional area of the ulnar nerve was significantly smaller than the size measured prior to surgery (P < .0001). The cross-sectional area of the median nerve was significantly correlated with that of the ulnar nerve (P < .05). However, no statistically significant difference was found between the patients with carpal tunnel syndrome and controls in ulnar nerve conduction. There were no statistically significant differences in nerve conduction study results or cross-sectional area of the ulnar nerve between patients with carpal tunnel syndrome with and without extramedian symptoms. CONCLUSIONS: The cross-sectional areas of the ulnar and median nerves at the wrist are increased in patients with carpal tunnel syndrome. Also, the cross-sectional area of the ulnar nerve is decreased after carpal tunnel release.

Ultrasound-Guided Lower Cervical Nerve Root Injectate Volumes Associated With Dorsal Root Ganglion and Epidural Spread.

OBJECTIVES: We aimed to estimate the spread of injections for ultrasound-guided cervical nerve root blocks and to determine the optimal injectate volume required in this procedure. METHODS: A total of 32 ultrasound-guided injections (C5-C8) were made in 4 fresh cadavers. The target on each cervical root was the space between the posterior tubercle and the cervical root at the most proximal location possible on the sonogram. After ultrasound-guided needle insertion, 0.5 mL of a contrast medium was injected 4 times. The dye flow patterns were confirmed with fluoroscopy each time, and we recorded whether the contrast medium reached the dorsal root ganglion level or the epidural space. After the injections, the needle tip location was determined by computed tomography and image reconstruction. RESULTS: All injections produced typical neurograms. The contrast medium reached the dorsal root ganglion in 29 of 32 (90.6%) injections (mean ± SD, 0.84 ± 0.42 mL of contrast medium) and the epidural space in 10 of 32 (31.3%) injections (1.30 ± 0.54 mL of contrast medium). The mean distance between the needle tip and neural foramen was 9.64 ± 3.68 mm, and this distance correlated positively with the volume of contrast medium necessary to reach the dorsal root ganglion or the epidural space. CONCLUSIONS: Ultrasound-guided cervical nerve root blocks show potential utility for targeting an anesthetic into the cervical root area. This study may be helpful for deciding the most appropriate volume for the procedure.

Cross-sectional area reference values of nerves in the lower extremities using ultrasonography.

INTRODUCTION: Cross-sectional area (CSA) reference values of lower extremity nerves using ultrasonography have only been reported in a few studies and have been limited to white populations. METHODS: For this study, 94 healthy Korean volunteers were recruited for measurement of the CSA at 7 sites of lower extremity nerves. The side-to-side difference in CSA was calculated for each nerve, and reference ranges were derived. External validity evaluation for the reference values was performed with 10 newly recruited volunteers at a different institution. RESULTS: Nerve CSA was correlated significantly with body mass index, weight, and height; however, the absolute value of the side-to-side difference had no significant correlation with demographic factors. The external validity was adequate for all sites, ranging from 80% to 100%. CONCLUSIONS: The lower extremity nerve CSA values obtained in this study may provide normal reference values for the Asian population.

Is median nerve enlargement at the wrist associated with tremor in Parkinson disease?

OBJECTIVES: Tremor is one of the cardinal features of Parkinson disease (PD) and may cause cumulative trauma-related injury to nerves of the hands. The aim of this study was to assess the electrodiagnostic and sonographic features of patients with PD and to assess the effect of tremor in PD on the median nerve. METHODS: We studied 31 hands of healthy control participants (n = 16; mean age ± SD, 60.25 ± 14.67 years) and 81 hands of patients with PD (n = 42; 64.95 ± 11.13 years). Motor symptoms were measured by the Unified Parkinson's Disease Rating Scale III. Median nerve conduction studies and sonographic cross-sectional area measurements were performed in all participants. RESULTS: The median nerve cross-sectional area in patients with PD (10.71 ± 2.79 mm(2)) was significantly larger than that in the control group (7.40 ± 1.05 mm(2); P < .05). However, there was no significant difference in median nerve electrodiagnostic findings between the PD and control groups. The median nerve cross-sectional area was associated with the severity of the tremor but not with the Unified Parkinson's Disease Rating Scale motor score. CONCLUSIONS: Tremor in PD is associated with median nerve enlargement but not with impairment of median nerve conduction.

Reference values for nerve ultrasonography in the upper extremity.

INTRODUCTION: The aims of this study were to identify factors affecting the measurement of nerve cross-sectional area (CSA) and to establish normal reference values for nerve ultrasonography of the upper extremity. METHODS: Ninety-seven age-matched, healthy individuals were enrolled. Ultrasonographic tests were performed by tracing nerves from the axilla to the distal arm. CSA was measured at the following locations: median nerve (carpal tunnel inlet, forearm, antecubital fossa, midhumerus); ulnar nerve (wrist, 2 cm proximal to the wrist, forearm, cubital tunnel outlet and inlet, midhumerus); radial nerve (spiral groove, antecubital fossa); and musculocutaneous nerve (proximal humerus). RESULTS: The CSA reference values differed between the measured points along the path of each nerve. Nerve CSA correlated significantly with weight, body mass index, height, and gender; however, the CSA ratio (distal/proximal) did not correlate with demographic factors. CONCLUSIONS: The normal reference values may be helpful in diagnosis of pathologies involving these nerves.

Carpal tunnel syndrome: Clinical, electrophysiological, and ultrasonographic ratio after surgery.

INTRODUCTION: The aim of this study was to improve our understanding of the pathophysiology of carpal tunnel syndrome (CTS) and to highlight the ultrasonographic cross-sectional area (CSA) ratio as a tool for assessing outcomes by investigating postoperative changes. METHODS: Twenty-four individuals with CTS were evaluated using the Boston questionnaire, nerve conduction studies, and ultrasound, preoperatively and at 3 weeks and 3 months postoperatively. RESULTS: Improved symptom scores, decreased CSA, and decreased CSA ratio were observed in the first 3 weeks, but functional improvement was also observed after 3 weeks postoperatively. The ratios between the CSA at the sites of enlargement and unaffected areas correlated significantly with the Padua classification, although the coefficient was not superior to the coefficient of CSA at the maximal swelling site. CONCLUSIONS: Symptoms improved more rapidly than function after surgery. Measurement of the ultrasonographic CSA ratio may provide clinicians with a useful assessment tool after surgery.

Measurement of cross-sectional area of cervical roots and brachial plexus trunks.

INTRODUCTION: The aim of this study was to determine normal reference values for cross-sectional area (CSA) and the correlation between demographic factors and CSA in the cervical roots and brachial plexus trunks using ultrasonography. METHODS: Ninety-five age-matched healthy individuals were studied. Ultrasonographic tests were performed via nerve tracing from the cervical root to the brachial plexus trunk. The CSA of each nerve was measured in the C5-8 ventral roots and brachial plexus (trunk level). RESULTS: Normal values of each cervical root were: C5, 5.66 ± 1.02 mm(2); C6, 8.98 ± 1.65 mm(2); C7, 10.43 ± 1.86 mm(2); and C8, 10.76 ± 2.02 mm(2). Values for the brachial plexus were: upper trunk, 16.70 ± 2.88 mm(2); middle trunk, 14.01 ± 2.70 mm(2); and lower trunk, 13.75 ± 2.57 mm(2). The side-to-side discrepancy was 11.91 ± 11.11%. Body mass index (BMI) and height correlated frequently with nerve CSA. CONCLUSIONS: These reference values may be helpful in investigating pathologies involving the cervical area.

Effect of platelet-rich plasma injections for chronic nonspecific low back pain: A randomized controlled study.

BACKGROUND: Patient with chronic nonspecific low back pain is weakened ligament, and prolotherapy is the effective treatment but their use remains controversial. These ligaments can be strengthened by platelet-rich plasma injection. We hypothesized that the effectiveness of platelet-rich plasma injection and prolotherapy may decrease pain and improved disability of patient with chronic low back pain. METHODS: This study was a prospective, double-blind, randomized controlled trial and was conducted for 3 years for patient enroll and follow-up. Thirty-four patients with chronic nonspecific low back pain (duration of at least 3 months) refectory to conventional management were randomized to platelet-rich plasma injection and lidocaine injection. Patients were treated with weekly platelet-rich plasma or lidocaine injections at the lumbopelvic ligaments for 2 weeks and then weekly prolotherapy with 15% glucose for 2 weeks and followed up 6 months. Visual analog scale, Oswestry Disability Index, and Roland-Morris Disability Questionnaire were evaluated at initial, 4 weeks, 3 months, and 6 months. Four patients did not complete this trial. Three were in the platelet-rich plasma injection and 1 was in the lidocaine injection. RESULTS: The intensity of pain was significantly decreased in platelet-rich plasma injections at 6 months as compared lidocaine injections; between-group differences were 0.9 (95% confidence interval 0.10-1.75 [P = .027]). All participants were significantly decreased pain and disability index at 4 weeks, 3 months, and 6 months but there were no significant differences between groups except for visual analog scale at 6 months. The baseline parameters were no significant differences in both groups. CONCLUSIONS: In chronic nonspecific low back pain, the platelet-rich plasma injection in combination with prolotherapy is an effective intervention and either lidocaine or platelet-rich plasma injection significantly reduced disability. And injection at the lumbopelvic ligaments using the platelet-rich plasma and prolotherapy is also an effective treatment for pain.

Carpal tunnel syndrome and tenosynovitis in women with breast cancer associated with hormone therapy: A multi-institutional analysis using a clinical data warehouse.

ABSTRACT: The study aims to evaluate the characteristics, treatments, and incidence rates of carpal tunnel syndrome (CTS) and tenosynovitis in women with breast cancer, according to the hormone therapy used. We retrospectively reviewed women with breast cancer identified from the clinical data warehouse of the six hospitals in Korea, from January 2015 to August 2020. Among them, patients with CTS or tenosynovitis were reviewed in terms of disease status and treatments. A total of 101 patients among a population of 15,504 met the study inclusion criteria, so their clinical data were analyzed. Aromatase inhibitor (AI) users frequently needed oral medication for CTS, and developed severe CTS which frequently required surgery. AI users presented with a higher incidence of CTS (1.3%) than patients without hormone therapy (0.4%), and tenosynovitis occurred at a higher rate in AI users (2.3%) compared to the tamoxifen (1.1%) and no hormone groups (0.5%). More than half of the CTS and tenosynovitis occurred within 12 months after hormone commencement. The incidence and disease characteristics of CTS and tenosynovitis differed among the groups depending on the type of hormone therapy received. Our findings will help clinicians understand clinical courses and treatments for CTS and tenosynovitis in breast cancer patients.

Avoiding false-negative nerve conduction study in ulnar neuropathy at the elbow.

INTRODUCTION: Ulnar nerve displacement at the elbow causes overestimation of nerve conduction velocity. We hypothesized that this overestimation may cause false-negative results when the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) diagnostic criteria are used. METHODS: We investigated 9 cases of ulnar neuropathy at the elbow, all having ulnar nerve displacement confirmed by ultrasonography and meeting none or just one of the AANEM criteria with distance measurement by anatomic landmarks. First, the distance across the elbow segment was measured by anatomic landmarks, and then it was re-estimated by ultrasonography. RESULTS: Overestimated ulnar conduction velocity was corrected by 7.9 m/s. Three cases met none of the AANEM criteria before correction. After correction of overestimation, all cases met two of the AANEM criteria. CONCLUSION: This study highlights the importance of using ultrasonography to confirm the possibility of ulnar nerve displacement, especially when electrodiagnostic findings do not meet AANEM criteria in patients with suspected UNE.

Median nerve changes following steroid injection for carpal tunnel syndrome.

INTRODUCTION: Neuromuscular ultrasound is a painless, radiation-free, high-resolution imaging modality for assessment of the peripheral nervous system. The purpose of this study was to use neuromuscular ultrasound to assess the changes that occur in the median nerve after steroid injection for carpal tunnel syndrome (CTS). METHODS: Ultrasound and nerve conduction studies were performed at baseline and 1 week, 1 month, and 6 months after steroid injection in 19 individuals (29 wrists) with CTS. RESULTS: Significant changes were noted in median nerve cross-sectional area (P < 0.001), mobility (P = 0.001), and vascularity (P = 0.042) at the distal wrist crease after steroid injection, and the nerve cross-sectional area correlated with symptom score and electrodiagnostic parameters. Changes in the ultrasonographic parameters were seen within 1 week of injection. CONCLUSIONS: These findings suggest neuromuscular ultrasound is potentially helpful for the assessment of individuals undergoing treatment for CTS, as typical changes can be expected after successful treatment injection.

Ultrasonographic evaluation of needle electromyography insertion into the tibialis posterior using a posterior approach.

OBJECTIVE: To estimate the safety window for needle insertion in the posterior approach to the tibialis posterior by ultrasonography, particularly in a clinical setting. DESIGN: Cross-sectional study. SETTING: University hospital. PARTICIPANTS: Healthy volunteers (108 legs, from 22 men and 32 women). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Distance between the tibia and neurovascular bundles in the posterior aspect of the tibia on a transverse ultrasonographic scan. RESULTS: The safety window at the midpoint was significantly larger than the upper third (0.62-2.16 cm, average 1.47 ± 0.38 cm vs 0.51-1.62 cm, average 1.16 ± 0.31 cm). The depth at the midpoint was significantly more shallow than the upper third (1.57-3.16 cm, average 2.31 ± 0.34 cm vs 1.76-3.66 cm, average 2.52 ± 0.38 cm). Body weight, height, tibial length, and leg circumference showed positive correlation with the safety window at both points. CONCLUSIONS: The midpoint may be more favorable than the upper third for needle insertion to the tibialis posterior with a posterior approach.

Clinical Practice Guideline for Postoperative Rehabilitation in Older Patients With Hip Fractures.

OBJECTIVE: The incidence of hip fractures is increasing worldwide with the aging population, causing a challenge to healthcare systems due to the associated morbidities and high risk of mortality. After hip fractures in frail geriatric patients, existing comorbidities worsen and new complications are prone to occur. Comprehensive rehabilitation is essential for promoting physical function recovery and minimizing complications, which can be achieved through a multidisciplinary approach. Recommendations are required to assist healthcare providers in making decisions on rehabilitation post-surgery. Clinical practice guidelines regarding rehabilitation (physical and occupational therapies) and management of comorbidities/complications in the postoperative phase of hip fractures have not been developed. This guideline aimed to provide evidence-based recommendations for various treatment items required for proper recovery after hip fracture surgeries. METHODS: Reflecting the complex perspectives associated with rehabilitation post-hip surgeries, 15 key questions (KQs) reflecting the complex perspectives associated with post-hip surgery rehabilitation were categorized into four areas: multidisciplinary, rehabilitation, community-care, and comorbidities/complications. Relevant literature from four databases (PubMed, EMBASE, Cochrane Library, and KoreaMed) was searched for articles published up to February 2020. The evidence level and recommended grade were determined according to the grade of recommendation assessment, development, and evaluation method. RESULTS: A multidisciplinary approach, progressive resistance exercises, and balance training are strongly recommended. Early ambulation, weigh-bearing exercises, activities of daily living training, community-level rehabilitation, management of comorbidities/complication prevention, and nutritional support were also suggested. This multidisciplinary approach reduced the total healthcare cost. CONCLUSION: This guideline presents comprehensive recommendations for the rehabilitation of adult patients after hip fracture surgery.

Adipose Tissue as Pain Generator in the Lower Back and Lower Extremity: Application in Musculoskeletal Medicine.

Description Adipose tissue (AT) has diverse and important functions in body insulation, mechanical protection, energy metabolism and the endocrine system. Despite its relative abundance in the human body, the clinical significance of AT in musculoskeletal (MSK) medicine, particularly its role in painful MSK conditions, is under-recognized. Pain associated with AT can be divided into intrinsic (AT as a primary pain generator), extrinsic (AT as a secondary pain generator) or mixed origin. Understanding AT as an MSK pain generator, both by mechanism and its specific role in pain generation by body region, enhances the clinical decision-making process and guides therapeutic strategies in patients with AT-related MSK disorders. This article reviews the existing literature of AT in the context of pain generation in the lower back and lower extremity to increase clinician awareness and stimulate further investigation into AT in MSK medicine.

Effect of Fascia Penetration in Lateral Femoral Cutaneous Nerve Conduction.

OBJECTIVE: To evaluate the effect of fascia penetration and develop a new technique for lateral femoral cutaneous nerve (LFCN) conduction studies based on the fascia penetration point (PP) identified using ultrasound. METHODS: The fascia PP of the LFCN was localized in 20 healthy subjects, and sensory nerve action potentials (SNAPs) were obtained at four different stimulation points-2 cm proximal to the PP (2PPP), PP, 2 cm distal to the PP (2DPP), and 4 cm distal to the PP (4DPP). We compared the stimulation technique based on the fascia penetration point (STBFP) with the conventional technique. RESULTS: The SNAP amplitude of the LFCN was significantly higher when stimulation was performed at the PP and 2DPP than at other stimulation points. Using the STBFP, SNAP responses were elicited in 38 of 40 legs, whereas they were elicited in 32 of 40 legs using the conventional technique (p=0.041). STBFP had a comparable SNAP amplitude and slightly delayed negative peak latency compared to the conventional technique. In terms of the time required, the time spent on STBFP showed a more consistent distribution than the time spent on the conventional technique (two-sample Kolmogorov-Smirnov test, p<0.05). CONCLUSION: SNAP of the LFCN significantly changed near the fascia PP, and stimulation at PP and at 2DPP provided high amplitudes. STBFP can help increase the response rate and ensure stable and consistent procedure time of the LFCN conduction study.

Investigation of the Diagnostic Value of Ultrasonography for Radial Neuropathy Located at the Spiral Groove.

OBJECTIVE: To determine a diagnostic cut-off value for the cross-sectional area (CSA) of the radial nerve using ultrasonography for radial neuropathy located at the spiral groove (SG). METHODS: Seventeen patients with electrodiagnostic evidence of radial neuropathy at the SG and 30 healthy controls underwent ultrasonography of the radial nerve at the SG . The CSAs at the SG were compared in the patient and control groups. The CSA at the SG between the symptomatic and asymptomatic sides (ΔSx-Asx and Sx/Asx, respectively) were analyzed to obtain the optimal cut-off value. The relationship between the electrophysiological severity of radial neuropathy and CSA was also evaluated. RESULTS: Among the variables examined, there were statistically significant differences in the CSA between the patient and control groups, ΔSx-Asx, and Sx/Asx at the SG. In a receiver operating characteristics analysis, the cut-off CSA was 5.75 mm2 at the SG (sensitivity 52.9%, specificity 90%), 1.75 mm2 for ΔSx-Asx (sensitivity 58.8%, specificity 100%), and 1.22 mm2 for Sx/Asx (sensitivity 70.6%, specificity 93.3%) in diagnosing radial neuropathy at the SG. There was no significant correlation between CSA and electrophysiological severity score for either patient group. CONCLUSION: The reference value obtained for CSA of the radial nerve at the SG may facilitate investigation of radial nerve pathologies at the SG.

Effect of Fascia Penetration on Sensory Nerve Conduction in the Superficial Radial Nerve.

PURPOSE: The aim of this study was to identify the effects of fascia penetration on superficial radial sensory nerve action potential amplitude. METHODS: The penetration point (PP) at which the nerve penetrated the brachioradialis fascia and became superficial was observed using ultrasonography. The sensory nerve action potential amplitude was measured at five points: the penetration point, 2 and 4 cm proximal to the PP, and 2 and 4 cm distal to the PP. RESULTS: The sensory nerve action potential amplitude at the penetration point and at 2 and 4 cm distal to the PP was significantly larger than that at 2 and 4 cm proximal to the PP. The largest amplitude was obtained 2 cm distal to the PP. CONCLUSIONS: The sensory nerve action potential of the superficial radial nerve changes significantly around the fascia penetration point.