T2 magnetic resonance imaging mapping and morphology of the median nerve before and after surgery in carpal tunnel syndrome.

INTRODUCTION/AIMS: T2 magnetic resonance imaging (MRI) mapping has been applied to carpal tunnel syndrome (CTS) for quantitative assessment of the median nerve. However, quantitative changes in the median nerve before and after surgery using T2 MRI mapping remain unclear. We aimed to investigate whether pathological changes could be identified by pre- and postoperative T2 MRI mapping of the median nerve in CTS patients after open carpal tunnel release. METHODS: This was a prospective study that measured median nerve T2 and cross-sectional area (CSA) values at the distal carpal tunnel, hamate bone, proximal carpal tunnel, and forearm levels pre- and postoperatively. Associations between T2, CSA, and nerve conduction latency were also evaluated. RESULTS: A total of 36 patients with CTS (mean age, 64.5 ± 11.7 years) who underwent surgery were studied. The mean preoperative T2 values significantly decreased from 56.3 to 46.9 ms at the proximal carpal tunnel levels (p = .001), and from 52.4 to 48.7 ms at the hamate levels postoperatively (p = .04). Although there was a moderate association between preoperative T2 values at the distal carpal tunnel levels and distal motor latency values (r = -.46), other T2 values at all four carpal tunnel levels were not significantly associated with CSA or nerve conduction latency pre- or postoperatively. DISCUSSION: T2 MRI mapping of the carpal tunnel suggested a decrease in nerve edema after surgery. T2 MRI mapping provides quantitative information on the median nerve before and after surgery.

Median nerve lesions in pediatric displaced supracondylar humerus fracture: A prospective neurological, electrodiagnostic and ultrasound characterization.

BACKGROUND AND PURPOSE: Supracondylar humerus fractures (SCHFs) are the most common elbow fractures in children. Traumatic median nerve injury and isolated lesions of its pure forearm motor branch, anterior interosseus nerve (AIN), have both been independently reported as complications of displaced SCHFs. Our main objectives were to characterize the neurological syndrome to distinguish median nerve from AIN lesions and to determine the prognosis of median nerve lesions after displaced SCHFs. METHODS: Ten children were prospectively followed for an average of 11.6 months. Patients received a standardized clinical examination and high-resolution ultrasound of the median nerve every 1-3 months starting 1-2 months after trauma. Electrodiagnostic studies were performed within the first 4 months and after complete clinical recovery. RESULTS: All children shared a clinical syndrome with predominant but not exclusive affection of AIN innervated muscles. High-resolution ultrasound uniformly excluded persistent nerve entrapment and neurotmesis requiring revision surgery but visualized post-traumatic median nerve neuroma at the fracture site in all patients. Electrodiagnostic studies showed axonal motor and sensory median nerve neuropathy. All children achieved complete functional recovery under conservative management. Motor recovery required up to 11 months and differed between involved muscles. CONCLUSIONS: It was shown that neurological deficits of the median nerve in displaced SCHFs exceeded an isolated AIN lesion. Notably, detailed neurological follow-up examinations and sonographic exclusion of persistent nerve compression were able to guide conservative therapy in affected children. Under these conditions the prognosis of median nerve lesions was excellent despite severe initial deficits, development of neuroma and axonal injury.

Factors Predicting Prolonged Mechanical Ventilation in Guillain-Barré Syndrome.

BACKGROUND: Up to 30% of patients with Guillain-Barré syndrome require mechanical ventilation and 5% die due to acute complications of mechanical ventilation. There is a considerable group of patients that will need prolonged mechanical ventilation (considered as >14 days) and should be considered for early tracheostomy. The objective of this study is to identify risk factors for prolonged mechanical ventilation. METHODS: We prospectively analyzed patients with Guillain-Barré diagnosis with versus without prolonged mechanical ventilation. We considered clinical and electrophysiological characteristics and analyzed factors associated with prolonged mechanical ventilation. RESULTS: Three hundred and three patients were included; 29% required mechanical ventilation. When comparing the groups, patients with prolonged invasive mechanical ventilation (IMV) have a lower score on the Medical Research Council score (19.5 ± 16.2 vs 27.4 ± 17.5, p = 0.03) and a higher frequency of dysautonomia (42.3% vs 19.4%, p = 0.037), as well as lower amplitudes of the distal compound muscle action potential (CMAP) of the median nerve [0.37 (RIQ 0.07-2.25) vs. 3.9 (RIQ1.2-6.4), p = <0.001] and ulnar nerve [0.37 (RIQ0.0-3.72) vs 1.5 (RIQ0.3-6.6), p = <0.001], and higher frequency of severe axonal damage in these nerves (distal CMAP ≤ 1.0 mV). Through binary logistic regression, severe axonal degeneration of the median nerve is an independent risk factor for prolonged IMV OR 4.9 (95%CI 1.1-21.5) p = 0.03, AUC of 0.774, (95%CI 0.66-0.88), p = < 0.001. CONCLUSIONS: Severe median nerve damage is an independent risk factor for prolonged mechanical ventilation.

Comparison of the Effectiveness of 2 Different Kinesio Taping Techniques Added to Exercises in the Treatment of Carpal Tunnel Syndrome: Randomized Controlled Trial, Double-Blind, Parallel Groups.

OBJECTIVE: To compare the effectiveness of I-tape and button hole kinesio taping (KT) techniques added to exercises in the treatment of carpal tunnel syndrome (CTS). DESIGN: Prospective randomized controlled blinded study. SETTING: Physical Medicine and Rehabilitation Outpatient Clinic. PARTICIPANTS: A total of 108 patients (165 wrists) diagnosed with CTS (N=108). INTERVENTIONS: Button hole technique (BG), I-band technique (IG), and exercises (EG). MAIN OUTCOME MEASURES: Visual analog scale (VAS), Douleur Neuropathique 4 Questions (DN4), Boston carpal tunnel syndrome questionnaire, and Jamar dynamometer were used. Median sensory nerve action potential (SNAP), compound muscle action potential (CMAP), median distal sensory latency (DSL), median distal motor latency (DML), sensory conduction velocity, and motor conduction velocity were recorded. Measurements were made at baseline, week 3, and week 12. RESULTS: Thirty-six patients were in each group. Significant statistical improvements in VAS and DN4 scores were found in the BG and IG compared with EG (P<.05). Statistically significant improvements in hand grip strength were observed in the IG compared with the EG (P<.05). Significant improvements in DML levels and motor conduction velocity were observed in the BG and IG compared with the EG (P<.05). A significant increase in sensory conduction velocity was detected in the BG compared with the other groups (P<.05). CONCLUSIONS: Both KT techniques are effective in terms of pain, functionality, symptom severity, grip strength, and electrophysiologically. The button hole technique was more effective in DSL, sensory conduction velocity, CMAP amplitude, and SNAP.

Alternative treatment of carpal tunnel syndrome with ultrasound-guided median nerve hydrodissection in the emergency department.

Hydrodissection is becoming increasingly recognized as a treatment for nerve entrapment syndromes in the orthopedic and rehabilitation world. Carpal Tunnel Syndrome (CTS) is the most prevalent nerve entrapment neuropathy, characterized by compression of the median nerve as it passes through the carpal tunnel. Initial management includes NSAIDs and wrist splints, but surgical intervention is often necessary when these measures fail. Ultrasound-guided hydrodissection of the median nerve is both safe and effective and presents a minimally invasive option when first-line treatments fail to provide adequate symptom relief. This case report demonstrates the potential for an alternative approach to analgesia in the Emergency Department (ED) for patients presenting with pain related to CTS. Here we discuss a case of a 26-year-old female presenting with CTS symptoms and her successful treatment with ultrasound-guided hydrodissection in the ED.

Peripheral nerve injuries associated with dislocated supracondylar fractures of distal humerus in children: incidence and need of surgical treatment.

PURPOSE: The objective of this study was to determine the incidence, necessity for neurosurgical intervention, and overall results of the treatment of pediatric peripheral nerve injuries associated with dislocated supracondylar fractures of the distal humerus. METHOD: A retrospective analysis of pediatric patients with supracondylar fractures treated from April 2019 to April 2022 with a minimum follow-up of 3 months was conducted. RESULTS: Of 453 included patients, there were 51 recorded peripheral nerve injuries. The ulnar nerve was the most frequently injured nerve. Nine patients required neurosurgical intervention, with the most common procedure being the release of entrapped nerves. The combination of a supracondylar fracture and arterial injury was identified as a significant risk factor for peripheral nerve injury (p < 0.001). Only one patient experienced an unsatisfactory outcome. CONCLUSION: Although the prognosis for peripheral nerve injuries in children with supracondylar fractures is generally favorable, these injuries must be properly identified. We recommend an active neurosurgical approach in children with persisting neurological deficits to minimize the risk of permanent neurological impairment.

Median Nerve Shear Wave Elastography Is Associated With the Neurophysiological Severity of Carpal Tunnel Syndrome.

OBJECTIVES: This study examines the associations between the median nerve (MN) shear wave elastography (SWE), the MN cross-sectional area (CSA), patient's symptoms, and the neurophysiological severity of carpal tunnel syndrome (CTS). The most appropriate site to perform SWE was also tested. METHODS: This prospective study comprised 86 wrists of 47 consecutive patients who volunteered for MN ultrasound after an electrodiagnostic study. The neurophysiological severity of CTS was assessed according to the results of a nerve conduction study (NCS). The MN CSA was measured at the carpal tunnel inlet (wCSA) and the forearm (fCSA). SWE was performed on the MN in a longitudinal orientation at the wrist crease (wSWE), at the forearm (fSWE), and within the carpal tunnel (tSWE). RESULTS: The wCSA and wSWE correlated positively with the neurophysiological severity of CTS (r = .619, P < .001; r = .582, P < .001, respectively). The optimal cut-off values to discriminate the groups with normal NCS and with findings indicating CTS were 10.5 mm2 for the wCSA and 4.12 m/s for the wSWE. With these cut-off values, wCSA had a sensitivity of 80% and specificity of 87% and wSWE a sensitivity of 88% and specificity of 76%. Neither tSWE nor fSWE correlated with the neurophysiological severity of CTS or differed between NCS negative and positive groups (P = .429, P = .736, respectively). CONCLUSION: Shear wave velocity in the MN at the carpal tunnel inlet increases in CTS and correlates to the neurophysiological CTS severity equivalently to CSA measured at the same site.

Identifying anatomic landmarks and median nerve characteristics for the analysis of persistent carpal tunnel syndrome using magnetic resonance imaging (MRI).

OBJECTIVE: Carpal tunnel syndrome (CTS) is the most common nerve entrapment neuropathy in the USA. In this study, we define anatomical landmarks to assess symptomatic and asymptomatic cohorts with persistent CTS using MRI imaging. MATERIALS AND METHODS: Distal vs proximal incomplete release was determined using the distal most aspect of the hook of hamate and the distal wrist crease. An incomplete release showed the transverse carpal ligament (TCL) intact at either boundary. Twenty-one patients with persistent CTS were analyzed for incomplete release, median nerve enlargement and T2 signal hyperintensity, and flattening ratio using postoperative wrist MRI. These findings were compared to a ten-patient asymptomatic persistent CTS control group. Fisher's exact and a Student's two-tailed t-tests were used to determine statistical significance. RESULTS: In the symptomatic persistent CTS group, 13 (61.9%) incomplete releases were identified, 5 (38.5%) incomplete distally, and 1 (7.7%) incomplete proximally. There was no statistical significance in the rate of incomplete releases when compared to the asymptomatic group (p = 1.00). T2 signal hyperintensity and enlargement at the site of release showed no statistical significance, (p = 0.319 and p = 0.999, respectively). The mean flattening ratio at the site of release in the symptomatic group (2.45 ± 0.7) was statistically significant compared to the asymptomatic group (1.48 ± 0.46), (p = 0.007). CONCLUSION: Utilizing the established landmarks, the full length of the TCL can be assessed via MRI. Additionally, evaluation of the median nerve flattening ratio at the level of the incomplete release may be utilized as an aid to the clinical management of persistent CTS.

Diagnostic efficacy of high-frequency Grey-scale ultrasonography and Sono-elastography in grading the severity of carpal tunnel syndrome in comparison to nerve conduction studies.

OBJECTIVES: To correlate the cross-sectional area (CSA) and elasticity of the median nerve (MN) measured at carpal tunnel inlet between healthy controls and various degrees of carpal tunnel syndrome (CTS) graded as per nerve conduction studies (NCS). MATERIALS AND METHODS: A total of 53 patients (with 81 wrists) presenting with clinical symptoms characteristic of CTS, having their diagnosis confirmed and severity graded by NCS, and 48 healthy controls (with 96 wrists) were included in the study. All the study participants underwent wrist ultrasound which included initial Grey-scale USG followed by strain and shear wave elastography. The CSA and elasticity (in terms of strain ratio and shear modulus) of MN were measured at the carpal tunnel inlet. Statistical analysis was performed using the Mann-Whitney U test to compare between the two groups and for subgroup analysis of cases. The diagnostic performance of each variable was evaluated using the receiver operating characteristic curves. RESULTS: The mean CSA was 9.20 ± 1.64, 11.48 ± 1.05, 14.83 ± 1.19 and 19.87 ± 2.68 mm2, the mean shear modulus was 17.93 ± 2.81, 23.59 ± 2.63, 32.99 ± 4.14 and 54.26 ± 9.24 kPa and the mean strain ratio was 5.26 ± 0.68, 5.56 ± 0.70, 7.03 ± 0.47 and 8.81 ± 0.94 in control, mild, moderate and severe grades of CTS, respectively (p < 0.001). CONCLUSION: The combined utility of Grey-scale USG and Elastography may serve as a painless and cost-effective alternative to NCS in grading the severity of CTS.

Median nerve ultrasonography in Parkinson's disease: a systematic review and meta-analysis.

BACKGROUND: The cross-sectional area (CSA) of the median nerve in Parkinson's disease remains unclear. OBJECTIVES: This meta-analysis assesses median nerve CSA changes in Parkinson's using ultrasonography. METHODS: PubMed, Web of Science, Scopus, and EBSCO were selectively searched for literature on Parkinson's disease, Median nerve, and ultrasonography. Following full-text screening, three studies were included in this meta-analysis with 144 Parkinson's disease patients and 127 controls. The primary outcome was the cross-sectional area of the median nerve; other motor parameters were also evaluated. RESULTS: The cross-sectional area of the median nerve was significantly increased in Parkinson's patients compared to controls (p = 0.007); the standardized mean difference was 0.79 [95% CI (0.21 - 1.37)]. The standardized mean difference of the motor parameters of the median nerve, amplitude, and latency was -0.04 [95% CI (-0.85 to 0.77)] and 0.30 [95% CI (-0.04 to 0.64)], respectively, with statistically insignificant (All p > 0.05). CONCLUSION: This meta-analysis concluded that the cross-sectional area of the median nerve is increased in Parkinson's disease patients. The increase in the CSA of the median nerve might explain the higher prevalence of carpal tunnel syndrome in Parkinson's disease. Further studies are needed to quantify carpal tunnel syndrome prevalence accurately in Parkinson's. LIMITATIONS: Heterogeneity exists due to non-standardized CSA calculation methods and varied disease stages. Finger movement during ultrasound may introduce artifacts, compromising CSA measurement accuracy. Establishing a definitive CSA cut-off for carpal tunnel syndrome in Parkinson's requires further investigation.

Evaluating the Need for Simultaneous Carpal Tunnel Release With Forearm Fasciotomy.

PURPOSE: The need to include simultaneous carpal tunnel release (sCTR) with forearm fasciotomy for acute compartment syndrome (ACS) or after vascular repair is unclear. We hypothesized that sCTR is more common when: 1) fasciotomies are performed by orthopedic or plastic surgeons, rather than general or vascular surgeons; 2) ACS occurred because of crush, blunt trauma, or fractures rather than vascular/reperfusion injuries; 3) elevated compartment pressures were documented. We also sought to determine the incidence of delayed CTR when not performed simultaneously. METHODS: Retrospective chart review identified patients who underwent forearm fasciotomy for ACS or vascular injury over a period of 10 years. Patient demographics, mechanism of ACS or indication for fasciotomy, surgeon subspecialty, compartment pressure measurements, inclusion of sCTR, complications, reoperations, and timing and method of definitive closure were analyzed. Logistic regression modeling was used to analyze predictors associated with delayed CTR. RESULTS: Fasciotomies were performed in 166 patients by orthopedic (63%), plastic (28%), and general/vascular (9%) surgeons. Orthopedic and plastic surgeons more frequently performed sCTR (67% and 63%, respectively). A total of 107 (65%) patients had sCTR. Fasciotomies for vascular/reperfusion injury were more likely to include sCTR (44%) compared with other mechanisms. If not performed simultaneously, 11 (19%) required delayed CTR at a median of 42 days. ACS secondary to fracture had the highest rate of delayed CTR (35%), and the necessity of late CTR for fractures was not supported by the logistic regression model. Residual hand paresthesias were less frequent in the sCTR group (6.5% vs 20%). Overall complication rates were similar in both groups (63% sCTR vs 70% without sCTR). CONCLUSION: When sCTR is excluded during forearm fasciotomy, 19% of patients required delayed CTR. This rate was higher (35%) when ACS was associated with fractures. Simultaneous CTR with forearm fasciotomy may decrease the incidence of residual hand paresthesias and the need for a delayed CTR. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognosis IV.

Diagnostic meta-analysis of the efficacy of ultrasonography for diagnosing carpal tunnel syndrome: A comparison between Asian and non-Asian populations.

BACKGROUND: Ultrasonography is used to diagnose carpal tunnel syndrome (CTS) according to various criteria. This diagnostic meta-analysis aimed to evaluate the efficacy of ultrasonography for diagnosing CTS, focusing on the cross-sectional area (CSA) of the median nerve (MN) at the inlet of the carpal tunnel and regional variations in diagnostic thresholds between Asian and non-Asian populations. METHODS: A comprehensive literature search was conducted using PubMed, Embase, and the Cochrane Library. The risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). Patient demographic data, diagnostic "gold standards", CSA cutoff values, and diagnostic results were extracted. Meta-analysis was performed to determine the sensitivity, specificity, and optimal CSA cutoff values. RESULTS: For the 25 included studies, a combined sensitivity of 88% and specificity of 84% for CSA measurements at the carpal tunnel inlet were obtained. The Asian group had a sensitivity of 84% and specificity of 86%, while the non-Asian group had a sensitivity of 91% and specificity of 82%. The mean CSA in the Asian group was significantly lower than that in the non-Asian group (12.93 mm2 and 14.77 mm2, respectively; p = 0.042). For the Asian group, the summary receiver operating characteristic curve had an area under the curve (AUC) of 0.92 with an optimal cutoff of 10.5 mm2; for the non-Asian group, an AUC of 0.94 was obtained with a cutoff of 11.5 mm2. CONCLUSION: Ultrasonography is a reliable diagnostic method for CTS, with distinct optimal cutoff values observed between Asian and non-Asian populations. Therefore, population-specific diagnostic criteria for CTS are recommended.

Reliability of Ultrasound Measurements of the Median Nerve in Asymptomatic Subjects Using a Handheld Device.

This study investigated the reliability of measuring the median nerve cross-sectional area (CSA) at the carpal tunnel inlet using a handheld ultrasound device (HUD) compared to a standard ultrasound system, focusing on intra- and inter-operator reproducibility among novice and expert operators. Employing a prospective cross-sectional design, 37 asymptomatic adults were assessed using both devices, with measurements taken by an expert with over five years of experience and a novice with less than six months. The CSA was determined using manual tracing and ellipse methods, with reproducibility evaluated through intraclass correlation coefficients (ICCs) and agreement assessed via Bland-Altman plots. Results showed a high degree of agreement between the devices, with excellent intra-operator reproducibility (ICC > 0.80) for the expert, and moderate reproducibility for the novice (ICCs ranging from 0.539 to 0.841). Inter-operator reliability was generally moderate, indicating acceptable consistency across different experience levels. The study concludes that HUDs are comparable to standard ultrasound systems for assessing median nerve CSA in asymptomatic subjects, with both devices providing reliable measurements. This supports the use of HUDs in diverse clinical environments, particularly where access to traditional ultrasound is limited. Further research with a larger sample and symptomatic patients is recommended to validate these findings.

Frequency-Specific Effects of Noninvasive Median Nerve Stimulation on Gastric Slow Wave Activity in Humans.

OBJECTIVES: The present study explored the effects of different frequencies of noninvasive median nerve stimulation (nMNS) on two autonomic responses: gastric slow waves under water-loading condition and heart rate variability (HRV). To the best of our knowledge, this is the first study to document the effects of different frequencies of nMNS on gastric slow waves (GSW) in humans under 5-minute water-loading condition. MATERIALS AND METHODS: Twenty healthy adult participants were fitted with a noninvasive body-surface gastric mapping, electrocardiogram (ECG), and a transcutaneous electrical nerve stimulation device and administered with four different nMNS frequencies (placebo-0 Hz, 40 Hz, 120 Hz, and 200 Hz) on four separate counterbalanced days. After the baseline and stimulation periods, a 5-minute water-load test was applied, and a post-water-load period also is recorded for ECG and GSW activity. Time-domain HRV parameters are analyzed with repeated-measures one-way analysis of variance (ANOVA) and a post hoc Tukey multiple comparison test. Parameters that failed normality tests underwent a Freidman test with a post hoc Dunn multiple comparison test. GSW data are analyzed with repeated-measures mixed-effects ANOVA. RESULTS: In empty stomach (baseline vs stimulation), only the 40-Hz frequency statistically significantly (p = 0.0129) increased GSW amplitude in comparison with its own baseline. In full (distended) stomach, 40-Hz and 200-Hz stimulations showed a statistically significant difference (post hoc multiple comparison adjusted, p = 0.0016 and p = 0.0183, respectively) in the Gastric Rhythm Index in comparison with the change obtained by placebo stimulation (baseline vs poststimulation periods); 120-Hz nMNS showed a statistically significant difference (p = 0.0300) in the stress index in comparison with the decrease observed in the placebo group. However, 120-Hz nMNS did not induce a statistically significant change in gastric electrical activity compared to placebo stimulation. The nMNS did not follow the linear "dose-response" relationship between nMNS frequency and gastric/HRV parameters. CONCLUSIONS: The 40-Hz and 200-Hz nMNS frequencies showed the most promising results in response to gastric distension, in addition to 40 Hz for an empty stomach. Further research is essential to explore the potential therapeutic effects of these frequencies on gastric diseases such as gastroparesis, gastroesophageal reflux disease, and functional dyspepsia that can be used in wrist wearables.

Immediate effects of Kinesio taping in carpal tunnel syndrome: A randomized controlled double-blind ultrasonographic study.

BACKGROUND: The effects of Kinesio taping (KT) in carpal tunnel syndrome are controversial. PURPOSE: This study aimed to examine whether KT has any effect on the skin, subcutaneous tissue, and median nerve measurements and to compare the effects of two different KT applications. STUDY DESIGN: This is a prospective, double-blinded, randomized trial. This study was prospectively registered on the clinicaltrials.gov (NCT05475197). A total of 34 wrists (21 patients) who were clinically and electrophysiologically diagnosed with mild/moderate carpal tunnel syndrome were randomly divided into two KT intervention groups (group 1: neural technique and area correction technique and group 2: area correction technique). METHODS: At baseline and immediately after the removal of KT (48 hours), pain was assessed with visual analog scale, hand grip strength with a hand-held dynamometer, and pinch strength using a pinch meter. Likewise, using ultrasound, skin and subcutaneous tissue thicknesses, median nerve cross-sectional area and flattening ratio, as well as median nerve depth were measured at the carpal tunnel inlet and outlet levels. RESULTS: While there was significant improvement in the pain scores (compared to the baseline) immediately after the KT in both groups (group 1: p = 0.03, ηp2 = 0.44; group 2: p < 0.001, ηp2 = 0.71), there was no difference in between (p = 0.07, ηp2 = 0.10). Grip strength significantly increased only in group 2 (p = 0.01, ηp2 = 0.35). None of the sonographic measurements displayed significant difference either within or between groups at baseline and after KT (all p > 0.05). CONCLUSIONS: While pain scores improved after KT, they were not coupled with any morphologic changes assessed by ultrasound.

A bilateral four-headed brachialis muscle with a variant innervation: a cadaveric report with possible clinical implications.

PURPOSE: Anterior compartment muscles of the arm present high morphological variability, with possible clinical significance. The current cadaveric report aims to describe a bilateral four-headed brachialis muscle (BM) with aberrant innervation. Emphasis on the embryological background and possible clinical significance are also provided. METHODS: Classical upper limb dissection was performed on an 84-year-old donated male cadaver. The cadaver was donated to the Anatomy Department of the National and Kapodistrian University of Athens. RESULTS: On the left upper limb, the four-headed BM was supplied by the musculocutaneous and the median nerves after their interconnection. On the right upper limb, the four-headed BM received its innervation from the median nerve due to the musculocutaneous nerve absence. A bilateral muscular tunnel for the radial nerve passage was identified, between the BM accessory heads and the brachioradialis muscle. CONCLUSION: BM has clinical significance, due to its proximity to important neurovascular structures and frequent surgeries at the humerus. Hence, knowledge of these variants should keep orthopedic surgeons alert when intervening in this area. Further dissection studies with a standardized protocol are needed to elucidate the prevalence of BM aberrations and concomitant variants.

Lacertus notch as a sign of lacertus syndrome.

OBJECTIVE: Many clinicians are unfamiliar with a diagnosis of lacertus syndrome (LS). We investigated the value of the lacertus notch sign in diagnosing LS. METHODS: We included 56 consecutive patients (112 upper extremities) who had neuropathic pain and neurological symptoms of the hand. The presence of LS and the lacertus notch sign in each upper extremity was assessed. RESULTS: Of the 83 upper extremities with LS, 54 (65.1%) had a lacertus notch sign, whereas 29 (34.9%) did not. Of the 29 upper extremities without LS, 9 (31.0%) and 20 (69.0%) had and did not have a lacertus notch sign, respectively. The rates of lacertus notch presence in upper extremities with and without LS were significantly different. Of the 63 upper extremities with a lacertus notch sign, 54 (85.7%) were diagnosed with LS, whereas 9 (14.3%) were not. Of the 49 upper extremities without a lacertus notch sign, 20 (40.8%) were diagnosed with LS, and 29 (59.2%) were not. We observed significant differences in the rates of LS in upper extremities with and without lacertus notch. CONCLUSIONS: The presence of the lacertus notch sign is useful for diagnosing LS. When patients with neuropathic pain and neurological symptoms present with a lacertus notch sign, clinicians should consider the possibility of LS.

A narrative review of pulsed radiofrequency for the treatment of carpal tunnel syndrome.

OBJECTIVE: Carpal tunnel syndrome (CTS), which is the most common peripheral nerve entrapment syndrome, can commonly persist despite conservative treatment modalities such as wrist splinting or medications. Pulsed radiofrequency represents a minimally invasive pain intervention technique to alleviate pain. The literature was reviewed to establish the effectiveness of PRF therapy for CTS. STUDY DESIGN: This is a narrative review of relevant articles on the effectiveness of PRF for CTS. METHOD: Four databases, MEDLINE, Cochrane Central Register of Controlled Trials, Embase, OVID Emcare, and Web of Science, were systematically searched. 804 records were screened, and the reference lists of eligible articles were examined. For this review, eight extracted studies were narratively explored. RESULTS: One case report, three retrospective cohorts, one observational prospective study, and three randomized-controlled trials were included. PRF likely provides both an analgesic and functional benefit in patients with mild to severe CTS, and it also shows benefit as an adjunct to carpal tunnel release surgery. Long-term data is limited. It also appears likely that steroid injection may represent a comparable treatment modality to PRF, and there have been positive results when these modalities are used together. Notably, all studies differed in their methodology, making direct comparisons between studies challenging. CONCLUSIONS: The evidence for PRF in the treatment of CTS, across the range of spectrum of severity or peri-operative to CTS surgery, appears favorable and avoids known side effects of steroid injections. Potential mechanisms for PRF and future directions for research are explored.

Corticosteroid injection for carpal tunnel syndrome: A meta-analysis comparing ultrasound guided approach with landmark approach.

Objective: To assess and compare the clinical and functional outcomes of corticosteroid injections in patients with carpal tunnel syndrome, focusing on two different approaches: ultrasound-guided and landmark-guided. Methods: A systematic search was conducted in PubMed, Scopus and Embase databases for relevant studies published prior to 30th April 2023. Studies that were either randomized controlled trials or had a cohort design were included. The review assessed symptom severity, functional status, electrodiagnostic parameters, complications, need for surgical intervention, visual analogue score, and grip strength. Pooled effect sizes were reported as relative risk (RR) or weighted mean difference (WMD). Results: A total of 8 articles were included. Compared to those that received steroid injection using landmark approach, those with ultrasound guided approach had lower symptom severity scale (SSS) score on Boston Carpal Tunnel Questionnaire (BCTQ) [WMD -0.50, 95% CI: -0.94, -0.07; I2=78.0%, N=7], lower risk of "any complications" [RR 0.58, 95% CI: 0.36, 0.93; I2= 22.9%, N=3] and lower risk of need for surgical intervention [RR 0.55, 95% CI: 0.34, 0.89; I2= 3.0%, N=2]. All other parameters were similar in the two groups i.e., functional status scale (FSS) score, visual analogue score (VAS) and grip strength. The electrophysiological findings were similar in the two groups. Conclusion: Findings suggest that ultrasound guided approach may be better than landmark guided approach especially in terms of alleviation of symptoms, reducing the risk of complications and need for surgical intervention. However, larger trials with long term follow up may provide conclusive evidence.

Elastography of nerves in the wrists of cyclists.

Purpose: This study aimed to investigate changes in the elasticity of the median and ulnar nerves in cyclists. Material and methods: The study included 30 cyclists and 2 non-biking reference groups that included 32 healthy volunteers and 32 individuals with ulnar nerve entrapment neuropathies. All participants underwent physical, ultrasonographic, and elastographic examinations including assessment of nerve cross-sectional area (CSA) and stiffness (SWE). The cyclists' group was tested before and after a 2-hour workout. Results: The values of ulnar nerve CSA and stiffness in Guyon's canal in resting cyclists were 5.30 ± 1.51 mm2 and 49.05 ± 11.18 kPa, respectively. These values were significantly higher than in the healthy volunteers, but not higher than in the nerve entrapment group. Median nerve CSA and stiffness at rest were 9.10 ± 2.61 mm2 and 38.54 ± 14.87 kPa, respectively. Both values were higher than respective values in the healthy group. Cycling induced an increase in all these parameters, although the increase in nerve stiffness was more noticeable than in CSA. Conclusions: The elasticity of the median and ulnar nerve in cyclists remains within normal limits, questioning the belief that cyclists are at risk of nerve palsy in Guyon's canal. However, cycling workout does exert compression, resulting in transient oedema of both nerves. The dynamics of changes was more noticeable in SWE examination than in conventional ultrasound, which may depend on SWE sensitivity.