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Carpal tunnel syndrome (CTS) is highly prevalent, resulting in decreased function and increased need for costly healthcare services. External wrist ratio (depth/width >0.70) is a strong predictor of the development of CTS and has been suggested to be a proxy for internal carpal tunnel (CT) shape. Conversely, sonography can more directly evaluate CT shape. The purpose of our study was to explore the relationship between wrist ratio and sonographic CT measurements to (1) evaluate the reliability of sonographic CT measurements and (2) explore how external wrist measures relate to anthropometric features of the CT. We used sonographic imaging on a sample of healthy participants (n = 226) to measure CT cross-sectional area, depth, width, and depth/width ratio. We conducted exploratory correlation and regression analyses to identify relationships of these measures with external wrist ratio. Reliability for dominant and nondominant sonographic CT measures ranged from good to excellent (0.79-0.95). Despite a moderate correlation between CT width and depth and their external wrist counterparts (0.33-0.41, p < 0.001), wrist ratio and CT ratio demonstrated weak to no correlation (dominant: r = 0.12, p = 0.053; nondominant: r = 0.20, p = 0.002) and the mean CT ratio was far lower than the mean wrist ratio (0.45 vs. 0.71 bilaterally). Supporting this, we observed several key differences in the relationship between external wrist measures compared to corresponding CT measures. Additionally, regression analyses combining participant factors and CT measurements produced models accounting for less than 15% of the variability in external wrist ratio (linear models) or correctly predicting less than 68% of wrist ratio-based risk categorization (logistic models). Overall, among healthy young adults, wrist shape is not an adequate proxy for CT shape., (© 2024 American Association of Clinical Anatomists and British Association of Clinical Anatomists.)

Competing Interests: Conflicts of interest The authors declare no conflicts of interest.

Objective: Decompression of the median nerve by complete endoscopic release of the transverse carpal ligament (TCL) and the distal antebrachial fascia. Minimization of surgical trauma results in decreased postoperative morbidity and earlier return to work and daily activities., Indications: Symptomatic carpal tunnel syndrome., Contraindications: Revision surgery after open or endoscopic procedure, rheumatic diseases., Surgical Technique: Small transverse incision at the ulnar border of the palmaris longus tendon, and proximal to the distal wrist flexion crease. Exposure and incision of the antebrachial fascia, dilatation of the carpal tunnel and dissection of synovial tissue from the undersurface of the TCL. With the wrist in extension, the endoscopic blade assembly with integrated camera is inserted into the canal. Exposure of TCL and short incision in the middle portion. Gradually, dissection of the distal portion of the TCL then completion by retraction of the blade distally to proximally., Postoperative Management: Slightly compressive dressing, selfcare on day 1 after procedure., Results: More than 25 years of experience, more than 8000 treated patients, and 3 documented cases with intraoperative lesions of the median nerve requiring revision. High acceptance and patient satisfaction in AQS1 patient-reported surveillance., (© 2023. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Background: The treatment of carpal tunnel syndrome (CTS) by sectioning the transverse carpal ligament (TCL) is not exempt from complications. Some nerve branches may be damaged by the incision. The aim of this study is to identify and map the TCL nerve endings, serving as a guide for sectioning this structure in a zone with less nerve ending density. Methods: Ten TCLs were obtained from fresh frozen cadavers. The TCLs were measured, divided into 3 equal bands (radial, central, and ulnar), and submitted to cryostat sectioning. The sections were subjected to immunofluorescence with the protein gene product (PGP) 9.5 and confocal microscopy analysis. Results: All the specimens contained type I and type IV mechanoreceptors. Neural elements occupied 0.695 ± 0.056% of the ligament area. The density of the neural elements was greater in the radial, followed by the ulnar and central bands, with 0.730 ± 0.083%, 0.686 ± 0.009%, and 0.669 ± 0.031%, respectively. Conclusion: The present findings suggest that the region with the least potential for neural element injury during TCL release is the central third near the transition with the ulnar third. When performed distally to proximally with a slight inclination from the radial to the ulnar, this release compromises the lowest nerve element density. Topographically, the proximal limit of the release is the distal wrist crease, while the distal limit is the intersection of Kaplan cardinal line and the axis of the third webspace.

Purpose: The main objective of this study was to identify anatomical differences between men and women in the absolute and relative size of the carpal tunnel (CT), its inner structures, and related external anatomical structures in order to shed light on the higher prevalence of CT syndrome (CTS) in women., Basic Procedures: We have dissected the forearms and hands of ten men and ten women and compared the cross-sectional area (CSA) of the CT between the two sexes. The size of the CT relative to the tendons passing through it, the median nerve (MN), and to hand and wrist size was also compared between men and women., Main Findings: The absolute CSAs of the CT and other parameters were larger in men than in women. The CSA of the CT relative to the length of the capitate bone was also larger in men. However, no significant differences were observed between men and women in the size of the CT relative to its inner structures., Principal Conclusions: The size of the inner structures of the CT are in proportion to that of the CT itself in both sexes. These findings suggest that the etiology of CTS seems to be primarily related to workload and personal traits., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Conflicts of interest The authors declare that they have no conflicts of interest., (Copyright © 2022 Elsevier GmbH. All rights reserved.)

Background: Wrist pressure and angulation while working at a computer workstation have been associated with cumulative trauma disorders (CTDs) like carpal tunnel syndrome (CTS)., Objective: This quantitative, comparative study analyzed wrist pressure and angulation between two common wrist supports while typing at a standardized computer workstation., Methods: A convenience sample of healthy young adults completed a five-minute typing task at a standardized workstation with no wrist support, with the ErgoBeads™ wrist support, and with an Elzo™ (memory foam) wrist support. Pressure mapping (Tekscan™)) and goniometry were used as quantitative measures to examine wrist pressure and wrist angulation during the typing task; descriptive and inferential statistics were performed to compare wrist angulation and wrist pressure between two supports., Results: For the sample (n = 54), both wrist supports demonstrated a significant (p < 0.001) reduction in wrist extension as well as pressure compared to typing at the workstation with no support. There was no statistically significant difference in peak or mean pressure between the ErgoBeads™ and Elzo™ wrist supports (p = 0.99). Significant difference was identified ((p < 0.001) for wrist angle as participants exhibited less wrist extension using the ErgoBeads™ (x¯=12.56∘; SD = 3.32°) support as compared to the Elzo™ (x¯=19.25∘; SD = 3.77°) support., Conclusions: The results suggest that the ErgoBeads™ and Elzo™ memory foam wrist supports are effective for reducing pressure between the wrist and work surface while the ErgoBeads™ support may promote a more neutral angle of the wrist while typing.

Background: The most prevalent neuropathy in the upper extremity is carpal tunnel syndrome (CTS). A variety of related risk factors such as biomechanical exposures, body mass index (BMI), sex and hand shape are reported to be related to CTS., Objective: We aimed to identify the role of BMI, hand, wrist and finger anthropometric dimensions in the development of CTS, and to compare these measured variables between control and CTS participants., Methods: A cross-sectional, case control study (n = 240, CTS = 120, controls = 120) with participants recruited from a convenience sample diagnosed with CTS and referred for anthropometric measurements. The control participants were matched by age and sex. The body height, weight, hand width, hand length, wrist depth, wrist width, wrist circumference, and finger length were measured. Hand, wrist and finger indices, hand to height ratio, and BMI were calculated. Mean values of all dimensions were compared between cases and controls, and the role of independent risk factors were determined by logistic regression analysis., Results: The mean BMI, age, weight, sex and height were not significant between the two groups. Among the measured dimensions and calculated indices the significantly different variables between two groups were the wrist width, wrist depth, wrist circumference, hand index, hand to height index, and wrist index. Regression analysis showed that the wrist index (β=-1.7, p = 0.0001), wrist depth (β=0.25, p = 0.0001) and wrist width (β=0.21, p = 0.0001) were the strongest factors in CTS development in the sample., Conclusion: Wrist parameters have a strong role in predicting the development of CTS, while BMI was not confirmed as an independent risk factor.

BACKGROUND. Ultrasound guidance allows performance of carpal tunnel release with smaller incisions and quicker recovery than traditional open or endoscopic surgery. OBJECTIVE. The purpose of this study was to evaluate the long-term effectiveness of ultrasound-guided carpal tunnel release in improving function and discomfort in patients with carpal tunnel syndrome. METHODS. Retrospective review was conducted of 61 ultrasound-guided carpal tunnel release procedures performed on 46 patients (15 bilateral procedures) with clinically diagnosed carpal tunnel syndrome. The procedures were performed with a single-use transection device and local anesthesia at an outpatient radiology office. Patients answered three questionnaires (Quick Disabilities of the Arm, Shoulder, and Hand [QDASH] and two parts of the Boston Carpal Tunnel Syndrome Questionnaire-the symptom severity [BCTSQ-SS] and functional status [BCTSQ-FS] scales) to assess the function of and discomfort in the affected wrist immediately before and 2 weeks and at least 1 year after the procedure. Higher scores indicated increasing disability. Patients also answered a global satisfaction question at follow-up. Preprocedure and postprocedure scores were compared by paired Wilcoxon signed rank tests. RESULTS. The 46 patients (25 women, 21 men; mean age, 60.6 years; range, 21-80 years) had median preprocedure scores of 45.4 for QDASH, 3.2 for BCTSQ-SS, and 2.5 for BCTSQ-FS. The median scores 2 weeks after the procedure were 22.5 for QDASH, 1.7 for BCTSQ-SS, and 1.9 for BCTSQ-FS. All scores decreased ( p < .001) from preprocedure scores and surpassed reference standards for clinically important difference in scores. Follow-up questionnaires obtained for 90% (55/61) of wrists a median of 1.7 years (range, 1.0-2.8 years) after the procedure showed further declines ( p < .001) in median scores: 2.3 for QDASH, 1.2 for BCTSQ-SS, and 1.1 for BCTSQ-FS. At long-term follow-up evaluation, 96% (52/54) of wrists had lower QDASH and 98% (53/54) had lower BCTSQ (average of BCTSQ-SS and BCTSQ-FS) scores compared with the preprocedure scores. Among the patients who participated in the survey, 93% (37/40) were satisfied or very satisfied with the long-term outcomes. No immediately postoperative complications occurred. Two patients needed surgical intervention 8 and 10 days after surgery, one for infection after injury and one for posttraumatic compartment syndrome. CONCLUSION. Ultrasound-guided carpal tunnel release quickly improves hand function and reduces hand discomfort; improvement persists beyond 1 year. CLINICAL IMPACT. Ultrasound-guided carpal tunnel release may be a safe, effective, and less invasive alternative to traditional surgery.

Carpal tunnel syndrome is an entrapment neuropathy that has been associated with the aggravation of tendon gliding resistance due to forceful, high velocity, awkwardly angled, and repetitive wrist motions. Cadaveric and epidemiological studies have shown that combinations of these risk factors have a more than additive effect. The aim of the current study was to develop a musculoskeletal model of the wrist that could evaluate these risk factors by simulating frictional work dissipated due to the gliding resistance of the third flexor digitorum superficialis tendon. Three flexion angle zones, three extension angle zones, five levels of task repetitiveness, and five levels of task effort were derived from ergonomic standards. Of the simulations performed by systematically combining these parameters, the extreme wrist flexion zone, at peak task repetitiveness and effort, dissipated the most frictional work. This zone dissipated approximately double the amount of frictional work compared to its equivalent zone in extension. For all motions, a multiplicative effect of the combination of task repetitiveness and effort on frictional work was identified by the musculoskeletal model, corroborating previous epidemiological and experimental studies. Overall, these results suggest that the ergonomic standards for wrist flexion-extension may need to be adjusted to reflect equivalent biomechanical impact and that workplace tasks should be designed to minimise exposure to combinations of highly repetitive and highly forceful work, especially when the wrist is highly flexed.

Objectives: Pinching, deviated wrist postures, and repetitive motion are risk factors for carpal tunnel syndrome. Hypervascularization of the median nerve and increased intraneural blood flow proximal to the carpal tunnel result in finger force and deviated wrist postures. The purpose of this study was to determine the effects of pinching with and without force, wrist posture, and repetitive wrist motion on intraneural blood flow in the median nerve., Methods: Eleven healthy and 11 carpal tunnel syndrome-symptomatic individuals completed 3 sections of this study: 15 pinch posture force trials, 3 repetitive wrist motion trials, and 3 static wrist posture trials. Intraneural blood flow (centimeters per second) was measured with pulsed wave Doppler ultrasound during each trial. Transverse B-mode images obtained from static trials were used to calculate the median nerve cross-sectional area and circumference., Results: An analysis of variance statistical analysis revealed significant main effects of pinch posture force (F 4,80 = 21.397; P < .001) and wrist posture (F 2,40 = 14.545; P < .001). Intraneural blood flow velocities were significantly greater when 6 N of force was applied by the thumb, finger, or pinch compared to no applied force in the same postures. Intraneural blood flow velocities were higher at 30° wrist flexion (mean ± SD, 2.24 ± 0.42 cm/s) than neutral (2.06 ± 0.45 cm/s) and 30° wrist extension (1.97 ± 0.46 cm/s). No changes were found in response to repetitive wrist motion., Conclusions: Flexed wrists as well as applied finger and thumb forces increase median nerve blood flow at the entry to the carpal tunnel, which may negatively affect the median nerve., (© 2020 American Institute of Ultrasound in Medicine.)

Background Flexor retinaculum reconstruction techniques or simply Flexor Retinaculum Z-lengthening have been proposed to preserve Flexor Retinaculum continuity after carpal tunnel release. Their effectiveness is based solely on symptom relief. There has been no analysis of the effects on intra-carpal tunnel pressure of Flexor Retinaculum-lengthening techniques. Objective was to compare intra-carpal tunnel pressure outcomes between complete division and Z-lengthening of the Retinaculum in a cadaveric model of carpal tunnel release. Methods Experimental study of carpal tunnel pressure after surgical Flexor Retinaculum modification in 10 fresh-frozen forearm and hand cadaveric specimens. The Kyphon™ Balloon Kyphoplasty system was used to measure the pressure before and after infusing 1, 2, 3, 4 and 5 ml of saline solution when untreated (Flexor Retinaculum continuity stage I), when Z-lengthened (Flexor Retinaculum continuity stage II), and after complete Flexor Retinaculum division (Flexor Retinaculum continuity stage III). Finding Intra-carpal tunnel pressure increased with larger volume of infused saline solution, although mean pressures were lower after Z lengthening or complete division of the Retinaculum than at baseline. Analysis of linear regression coefficients indicated significant differences as a function of FR continuity stage (F(2,18) = 18.38, p < 0.001), while the Bonferroni test revealed significant differences in slopes between stages I and III (p = 0.003), between stages I and II (p < 0.02), but not between stages II and III (p > 0.05). Interpretation The effectiveness of carpal tunnel release and the reduction in intra-carpal tunnel pressures obtained by Z-lengthening of the FR were similar to those observed after its complete division, while preserving FR continuity., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The transverse carpal ligament (TCL), the main part of the flexor retinaculum, serves as an anchor for the thenar muscles: abductor pollicis brevis (APB), superficial head of the flexor pollicis brevis (sFPB), and opponens pollicis (OPP). Biomechanically, the thenar muscles rely on their TCL anchoring to transmit muscle contractions distally for thumb force and motion production, and reciprocally, muscle contraction interacts with the TCL at the proximal end through the origins. However, scarce knowledge exists regarding the distribution pattern of the thenar muscle origins. The purpose of this study was to understand the anatomical interface between the thenar muscles and TCL by examining the origin distributions of the individual muscles. Ten cadaveric specimens were dissected for digitization of the muscle origins and TCL volar surface. Digitized data were used for mesh reconstruction and calculation of surface areas and centroids. The origin areas for APB, sFPB, and OPP were 105.8 ± 30.3, 64.6 ± 15.2, and 245.9 ± 70.7 mm 2 , respectively. The surface area of the TCL was 386.2 ± 86.9 mm 2 . The origin areas of APB and OPP on the TCL were comparable, 18.4 ± 4.8% and 17.3 ± 9.6% of the TCL area, respectively. The origin locations for APB, sFPB, and OPP were in proximal-radial quadrant of the TCL, on distal aponeurosis outside the TCL, and around the ridge of trapezium, respectively. The knowledge of the anatomical interface provides a foundation for the understanding of biomechanical interactions between the muscles and ligaments and pathomechanical implications., (© 2020 Wiley Periodicals, Inc.)

Background: Osteochondroma is a benign tumor that occurs mainly at the metaphysis of long bones and seldom arises from carpal bones. We describe an extremely rare case of osteochondroma of the hamate without a typical cartilaginous cap and with a spiky bony protrusion in an elderly patient., Case Presentation: A 78-year-old right-handed female housekeeper had a multilobed osteochondroma of the hamate, which caused carpal tunnel syndrome and irritation of the flexor tendons. Radiological examinations showed a morphological abnormality of the hamate comprising a spiky bony protrusion into the carpal tunnel and a free body proximal to the pisiform. Open carpal tunnel release and resection of the spiky bony protrusion on the hook of the hamate were performed. The flexor digitorum profundus tendons of the ring and little fingers displayed synovitis and partial laceration in the carpal tunnel. Histological examination also showed atypical findings: only a few regions of cartilaginous tissue were seen in the spiky bony protrusion, whereas the free body proximal to the pisiform contained thick cartilaginous tissue such as a cartilaginous cap typical of osteochondroma. We speculated that the bony protrusion to the carpal tunnel had been eroded by mechanical irritation caused by gliding of the flexor tendon and had resulted in the protruding spiky shape with less cartilaginous tissue. The fractured cartilaginous cap had moved into the cavity within the carpal tunnel proximal to the pisiform and had become a large free body., Conclusions: Osteochondroma of the carpal bone may take various shapes because the carpal bone is surrounded by neighboring bones and tight ligaments, which can restrict tumor growth. This type of tumor is likely to present with various symptoms because of the close proximity of important structures including nerves, tendons, and joints. The diagnosis of osteochondroma of the carpal bone may be difficult because of its rarity and atypical radiological and histological findings, such as the lack of a round cartilaginous cap. We suggest that surgeons should have a detailed understanding of this condition and should make a definitive diagnosis based on the overall findings.

This study investigated the connections between the median nerve paraneural sheath and myofascial structures near it, from both macroscopic and microscopic points of view. Four samples of median nerve and surrounding tissues were excised from nine non-embalmed upper limbs for microscopic analysis. Ultrasound images were analysed in 21 healthy subjects and 16 carpal tunnel syndrome patients to evaluate median nerve transversal displacement during finger motion at carpal tunnel and forearm levels. An anatomical continuity between epimysium and paraneural sheath and a reduction of paraneural fat tissue from proximal to distal was found in all samples. Median nerve displacements at both levels were significantly reduced in carpal tunnel syndrome subjects (P < 0.001). It was observed that the median nerve is not an isolated structure but is entirely connected to myofascial structures. Therefore, unbalanced tension of epimysial fasciae can affect the paraneural sheath, limiting nerve displacement, and consequently this must be included in carpal tunnel syndrome pathogenesis., (© 2019 Anatomical Society.)

Background: Corticosteroid injection into the carpal tunnel is both a diagnostic test and a therapeutic modality in the treatment of carpal tunnel syndrome. Many injection techniques are described in the literature. Improper placement of injection may result in damage to neurovascular structures in the carpal canal or decrease efficacy of the test and/or therapy. The purpose of this study is to determine if carpal tunnel injection using anatomic landmarks is reproducible and safe. A review of the senior author's injection technique is presented. Methods: Over 8 years, there were 756 attempted placements of a 25-gauge needle into the carpal tunnel in a simulated carpal tunnel injection prior to open carpal tunnel release. The needle was inserted at the wrist crease, just ulnar to palmaris longus. Open carpal tunnel release was subsequently performed, and position of the needle was recorded. Results: In 572 patients (75.7%), the needle was found to be in the carpal tunnel without penetration of contents. The needle was in the carpal tunnel but piercing the median nerve in 66 attempts (8.7%). The carpal tunnel was missed in 118 attempts (15.6%). Conclusions: This is the largest study looking at accuracy of carpal tunnel injection using anatomic landmarks. Our injection accuracy (75.7%) is less than reported in previous studies, which note 82% to 100% accuracy using the same injection technique. This may indicate that carpal tunnel injection is less reliable than previously thought. Safety of carpal tunnel injection remains an important concern. The median nerve was penetrated in 8.7% of attempts.

Introduction: After noting inconsistent sonographic median nerve cross-sectional area (CSA) enlargement at the wrist in very elderly patients with carpal tunnel syndrome (CTS), we systematically reviewed ultrasound, electrodiagnostic, and clinical data collected over a 12-month period in patients from 2 age groups: 80-95 years and 40-65 years old., Methods: Clinical and electrodiagnostic CTS severity, sensitivity of ultrasound CSA (against both electrodiagnostic and clinical reference standards), and correlations between ultrasound CSA and clinical and electrodiagnostic severity were compared in both groups., Results: In very elderly patients, despite a higher prevalence of severe CTS, nerve ultrasound was less sensitive than in the younger group (54% vs. 87%, using clinical reference standard), and did not correlate with clinical (r = 0.28, P = 0.10) or electrodiagnostic (r = 0.09, P = 0.60) severity., Discussion: Median nerve ultrasound CSA at the wrist is not a sensitive marker of CTS in very elderly populations. In this work we detail and discuss potential pathophysiological underpinnings of this unexpected finding. Muscle Nerve, 2019., (© 2019 Wiley Periodicals, Inc.)

Objectives: We conducted a large cohort study to investigate the association between work-related wrist movements and carpal tunnel syndrome (CTS)., Methods: Electro-goniometric measurements of wrist movements were performed for 30 jobs (eg, office work, child care, laundry work and slaughterhouse work). We measured wrist angular velocity, mean power frequency (MPF) and range of motion (ROM). We established a cohort of Danish citizens born 1940-1979 who held one of these jobs from age 18-80 years, using Danish national registers with annual employment information from 1992 to 2014. We updated the cohort by calendar year with job-specific and sex-specific means of measured exposures. Dates of a first diagnosis or operation because of CTS were retrieved from the Danish National Patient Register. The risk of CTS by quintiles of preceding exposure levels was assessed by adjusted incidence rate ratios (IRR adj ) using Poisson regression models., Results: We found a clear exposure-response association between wrist angular velocity and CTS with an IRR adj of 2.31 (95% CI 2.09 to 2.56) when exposed to the highest level compared with the lowest. MPF also showed an exposure-response pattern, although less clear, with an IRR adj of 1.83 (1.68 to 1.98) for the highest compared with the lowest exposure level. ROM showed no clear pattern. Exposure-response patterns were different for men and women., Conclusions: High levels of wrist movement were associated with an increased risk of CTS. Preventive strategies should be aimed at jobs with high levels of wrist movements such as cleaning, laundry work and slaughterhouse work., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose of Review: Carpal tunnel syndrome (CTS) is an entrapment neuropathy that involves the compression of the median nerve at the wrist and is considered the most common of all focal entrapment mononeuropathies. CTS makes up 90% of all entrapment neuropathies diagnosed in the USA and affects millions of Americans., Recent Findings: Age and gender likely play a role in the development of CTS, but additional studies may further elucidate these associations. Of known associated risk factors, diabetes mellitus seems to have the greatest association with CTS. One of the most commonly reported symptoms in CTS is a "pins-and-needles" sensation in the first three fingers and nocturnal burning pain that is relieved with activity upon waking. Treatment for CTS is variable depending on the severity of symptoms. Conservative management of CTS is usually considered first-line therapy. In cases of severe sensory or motor deficit, injection therapy or ultimately surgery may then be considered. Still CTS is often difficult to treat and may be reoccurring. Novel treatment modalities such as laser and shockwave therapy have demonstrated variable efficacy though further studies are needed to assess for safety and effect. Given the unknown and potentially complex etiology of CTS, further studies are needed to explore combinations of diagnostic and therapeutic modalities.

Introduction: No consensus exists about the upper limit of normal (ULN) of the cross-sectional area (CSA) of the median nerve in diagnosing carpal tunnel syndrome (CTS). Previously, we demonstrated a strong positive correlation between wrist circumference and CSA. ULN depending on wrist circumference turned out to have a low sensitivity, which was hypothesized to be caused by an age mismatch. The aim of this study was to re-evaluate the found invariance by augmentation of the healthy control group, adding older subjects, and to determine the diagnostic accuracy of the updated normal values., Methods: CSA and wrist circumference were measured in an additional 42 healthy controls in the ages of 40-60. Univariable and multivariable linear regression analyses were applied to determine predicting factors for CSA. Diagnostic accuracy was assessed in a prospective cohort of 253 patients., Results: A strong correlation was found between wrist circumference and CSA (r = 0.61). Wrist circumference is the most important independent predictor for ULN (r 2  = 0.37). We managed to simplify our newly derived regression equations, which turned out to be unrelated to age. Sensitivity of our new equations is low, but higher than a general fixed cut-off value (53.4% and 47.4%, respectively)., Discussion: Wrist circumference is the most important independent predicting factor of CSA. By using our updated equations and taking wrist circumference into account, one can determine a more precise ULN for each individual, which will lead to the improvement of the diagnostic accuracy of ultrasonography (US). Sensitivity for US in diagnosing CTS remains low and it can therefore not replace EDX.

Background: Carpal tunnel syndrome is a compression neuropathy at the wrist associated with compromised median nerve mobility. The purpose of this study was to investigate the effects of radioulnar wrist compression on median nerve longitudinal mobility within the carpal tunnel in carpal tunnel syndrome patients as well as healthy subjects., Methods: Dynamic ultrasound images captured longitudinal median nerve motion in the carpal tunnel during radioulnar wrist compression force application in 11 healthy subjects and 11 carpal tunnel syndrome patients., Findings: We found that median nerve mobility was not significantly affected by radioulnar wrist compression in healthy subjects (P = 0.34), but improved by 10 N radioulnar wrist compression in carpal tunnel syndrome patients (P < 0.05). Analysis of segmental median nerve mobility in carpal tunnel syndrome patients showed significantly improved mobility in the proximal tunnel section under 10 N radioulnar wrist compression force condition compared to the no compression condition (P < 0.05)., Interpretation: Moderate radioulnar wrist compression force application helps restore impaired median nerve mobility and may be effective in improve nerve function and symptoms associated with carpal tunnel syndrome., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objective: To analyze the influence of simulation mouse use motion under different wrist forcing postures on median nerve, tendons and ligaments in the carpal tunnel. Methods: From June to November in 2017, a total of 49 healthy volunteers [aged from 18 to 27 years, 24 males (48 cases of hands) and 25 females (50 cases of hands)] were selected in the Institute of Digitized Medicine and First Affiliated Hospital of Wenzhou Medical University.Three hand postures of the volunteers were simultaneously and continuously measured by using LOGIQ E9 ultrasonic diagnostic apparatus and Zebris foot pressure distribution measurement system.Seventeen parameters of nerves, tendons and ligaments in carpal tunnel were observed under natural (0 N), and two forced (25 and 50 N) states.Double factor variance analysis was performed with generalized estimating equation (GEE). Results: With increasing pressure (0, 25 and 50 N) of hand postures, the distance between median nerve and transverse carpal ligament were all less than 0.2 cm.The differences in both the distance between median nerve and flexor pollicis longus under the hand pressure changes or under the hand posture changes and the top angle of a triangle composed of median nerve, flexor pollicis longus and flexor digitorum superficialis group under the hand pressure changes or under the hand posture changes were all significant under the GEE analysis (all P <0.01). There were no significant changes in all other structural parameters in the carpal tunnel with the increasing of hand pressure (all P >0.05). Conclusions: The influence of the transverse carpal ligament to the median nerve belongs to the mechanism of pressure-induced irritation damage.The influence of flexor pollicis longus to median nerve belongs to the mechanism of tension-induced irritation damage.The influence of flexor digitorum superficialis to median nerve belongs to the mechanism of mixed shear irritation damage.

Study Design: Cross-sectional study., Background: The carpal tunnel is a clinically important fibro-osseous conduit for the median nerve and associated tendons. It is mechanically dynamic and therapeutic manual techniques that appear to move and change tunnel shape is part of clinical practice., Objectives: To measure changes in dimensions of the carpal tunnel and median nerve with manual mobilization of the carpal bones in cadavers., Methods: A total of 20 cryopreserved upper extremities from cadaveric specimens were used in the study. The wrist was cut using an anatomical saw at the level of the pisiform. Measurements of the cross-sectional area (CSA), anteroposterior diameter (APD), transverse diameter (TD), perimeter, flattening ratio and circularity of the carpal tunnel and of the median nerve, were taken, both in the anatomical position of the wrist and during the mobilization technique of the carpal bones., Results: During the mobilization technique, the tunnel CSA (p < 0.011), APD (p < 0.001) and circularity (p < 0.001) significantly increased, while TD (p < 0.001), perimeter (p < 0.004) and flattening ratio (p < 0.001), decreased. The median nerve showed similar behavioral tendencies to the tunnel but only the CSA (p < 0.005), APD (p < 0.005) and flattening ratio (p < 0.004) of the nerve showed significant differences., Conclusion: Application of external manually applied compressive force across the wrist can increase the CSA of the carpal tunnel and the median nerve in cadavers. These results are consistent with other studies in which similar results were found non-invasively using ultrasound., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Introduction: The carpal tunnel is a clinically important fibro-osseous conduit for the median nerve and associated tendons. It is mechanically dynamic, such that the dimensions of the tunnel and median nerve change with position, movement and application of externally applied force with mechanical devices. Therapeutic manual techniques that appear to move and change tunnel shape are part of clinical practice. The aim of this study was therefore to measure changes in dimensions of the carpal tunnel and median nerve with manual mobilization of the carpal bones., Material and Methods: An analytical descriptive study with 18 volunteer subjects and a total of 33 records was designed. Ultrasound measurements of the cross-sectional area (CSA), anteroposterior diameter (APD), transverse diameter (TD), perimeter, flattening ratio and circularity of the carpal tunnel and of the median nerve, were measured, both in the anatomical position of the wrist and during mobilization techniques of the carpal bones., Results: During the mobilization technique, the tunnel (p = 0.003) CSA significantly increased. APD also increased significantly for the tunnel (<0.001) while TD decreased. The median nerve showed similar and significant (p < 0.001) changes than the tunnel. However, because several of the obtained differences where smaller than the SDD obtained in a previous study, these differences were considered as irrelevant., Conclusions: Manual mobilization of the carpal bones produced significant changes in the dimensions of the carpal tunnel., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Carpal tunnel syndrome (CTS) is the most common upper extremity entrapment neuropathy and various risk factors have been implicated in the etiology. In this study, we aimed to determine whether anthropometric measurements are independent risk factors for CTS. Patients with symptoms of CTS (n = 27) and asymptomatic controls (n = 27) were enrolled following electrophysiological confirmation. Body mass index (BMI) was recorded and anthropometric measurements of the hand were made by a digital caliper. BMI, wrist width, wrist depth, palm length, hand width, wrist ratio, wrist/palm ratio, and wrist/hand ratio were significantly higher in the CTS group. BMI, wrist ratio, wrist/palm ratio, and wrist/hand ratio were independent variables in the logistic regression analysis; wrist ratio was the only significant predictor of CTS. Patients with a wrist ratio higher than 0.69 were 8.2 times more likely to have CTS. This study suggests that wrist ratio may be considered as an independent risk factor for CTS. Clin. Anat. 31:698-701, 2018. © 2018 Wiley Periodicals, Inc., (© 2018 Wiley Periodicals, Inc.)

Radiographs are indicated as the first imaging test in all patients with chronic wrist pain, regardless of the suspected diagnosis. When radiographs are normal or equivocal, advanced imaging with MRI (without or without intravenous contrast or following arthrography), CT (usually without contrast), and ultrasound each has a role in establishing a diagnosis. Furthermore, these examinations may contribute to staging disease, treatment planning, and prognostication, even when radiographs are diagnostic of a specific condition. Which examination or examinations are best depends on the specific location of pain and the clinically suspected conditions. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment., (Copyright © 2018 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Background: Carpal tunnel syndrome (CTS) is commonly seen in elderly populations, in part due to increased presence of predisposing comorbidities as well as physiological changes. We aimed at comparing the effectiveness of different doses of steroid using the ultrasound-guided hydrodissection method in elderly patients with CTS., Methods: We conducted a prospective, triple-blind, randomized, controlled trial in elderly patients with CTS. Patients were allocated to one of three groups by simplified randomization. Groups I-III received 80 mg triamcinolone (2 mL) and 1 mL of 2% lidocaine; 40 mg triamcinolone (1 mL), 1 mL of 2% lidocaine, and 1 mL normal saline; and 1 mL of 2% lidocaine and 2 mL normal saline, respectively to make up to 3 mL volume. A wrist splint was then applied for support. Outcome measures included the visual analog scale (VAS) and the Boston Carpal Tunnel Questionnaire, and median motor and sensory nerve conduction and its sonographic inlet cross-sectional area were used as objective measures. All data were recorded at baseline and 2, 12, and 24 weeks after injection. The investigators, patients, and statistician were blinded to the treatment assignment., Results: In total, 161 patients were recruited without statistically significant demographic differences between the three groups. There were no statistically significant differences between groups in any outcome, with the exception of the median distal motor latency, which was greater in Group II at all three follow-up visits, and significant baseline VAS difference between Groups I and III., Conclusion: Hydrodissection with lidocaine and normal saline is as effective as hydrodissection with low- and high-dose steroid medication in elderly patients with CTS in this study, but further studies with matched baseline measures and also a sham group are suggested for definitive recommendation., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy occurring in upper limbs. The etiology, however, has not been fully understood yet. Median nerve could be compressed by either increase of carpal tunnel pressure (CTP) or direct impingement when it is forced toward to carpal ligament especially in wrist flexion leading to CTS development. Thus, the increase of carpal tunnel pressure is considered an important role in CTS development. It has been identified that forces applied to the palm would affect the CTP. However, the quantitative relationship between palmar contact force and CTP is not known. The purpose of this study was to quantitatively evaluate the relationship between palmar contact force and CTP. Eight human cadaveric hands were used. The CTP was measured with a diagnostic catheter-based pressure transducer inserted into the carpal tunnel. A custom made device was used to apply forces to the palm for the desired CTP. Palmar contact forces corresponding to the determined CTP level were recorded respectively. The testing was repeated with different ranges of tension applied to the flexor digitorum superficialis tendon of the third finger. The tensions were constant at 50 g for the other flexor tendons and median nerve. The results showed that CTP increased linearly with the force applied to the palm. When CTP was 30 mmHg, mean values of the contact force to the palm was 293 g (SD: 15.2) including all tensions. These results would help to understand the effect of daily activities with hands on CTP., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Morphology of the carpal tunnel changes with varying wrist postures and compressive forces applied to the wrist. These changes may affect the morphology and pressure on the median nerve and could be used as part of the treatment of the carpal tunnel syndrome patients. Reliability of the ultrasonographic measurements of the median nerve has been widely studied. However, there is a lack of investigation regarding reliability of ultrasonographic measurements of the carpal tunnel., Objective: The purpose of this study was to assess intra-tester and inter-tester reliability of measurement of dimensions of the carpal tunnel and median nerve with ultrasound in asymptomatic volunteers., Design: A cross-sectional methodological study., Methods: Aspects measured were mediolateral and anteroposterior diameters, flattening ratio, circularity, perimeter and cross-section area of the carpal tunnel and median nerve., Results: Intra-tester reliability was excellent for the carpal tunnel (ICCs from 0.91 to 0.97) and for the median nerve (ICCs from 0.79 to 0.94) measurements. The flattening ratio of the median nerve showed good agreement (ICC = 0.68). Inter-tester reliability was excellent for the carpal tunnel measurements (ICCs from 0.76 to 0.95) and, for the cross sectional area, the perimeter and mediolateral diameter of the median nerve, the ICC values were 0.89, 0.84 and 0.81, respectively., Conclusion: In the context of this study, ultrasound was a reliable instrument for measuring carpal tunnel and median nerve dimensions in asymptomatic subjects., Level of Evidence: 1b., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Introduction: Previous studies have reported higher wrist ratios (WR) related to carpal tunnel syndrome (CTS) but have not assessed effect modification by obesity and may have inadequately controlled for confounders., Methods: Baseline data of a multicenter prospective cohort study were analyzed. CTS was defined by nerve conduction study (NCS) criteria and symptoms., Results: Among the 1,206 participants, a square-shaped wrist was associated with CTS after controlling for confounders (prevalence ratio = 2.27; 95% confidence interval [95% CI], 1.33-3.86). Body mass index (BMI) was a strong effect modifier on the relationship between WR and both CTS and abnormal NCS results, with normal weight strata of rectangular versus square wrists = 8.18 (95% CI, 1.63-49.96) and 7.12 (95% CI, 2.19-23.16), respectively., Discussion: A square wrist is significantly associated with CTS after controlling for confounders. Effect modification by high BMI masked the eightfold magnitude adjusted relationship seen between WR and CTS among normal weight participants. Muscle Nerve 56: 1047-1053, 2017., (© 2017 Wiley Periodicals, Inc.)

Introduction: An ultrahigh-frequency (70 MHZ) ultrasound device has recently been approved for human use. This study seeks to determine whether this device facilitates counting of fascicles within the median nerve at the wrist., Methods: Twenty healthy volunteers underwent imaging of the median nerve at the wrist bilaterally. The number of fascicles in each nerve was counted by two independent raters., Results: The mean fascicle number was 22.68. Correlation was strong between the two raters (r = 0.68, P < 0.001). Age, sex, body mass index, and nerve area did not predict fascicle number. Those with bifid median nerves and persistent median arteries had lower fascicle density than those without anatomic anomalies (1.79 vs. 2.29; P = 0.01)., Discussion: Fascicles within the median nerve at the wrist can be readily imaged. Ultrahigh-frequency ultrasound technology may be informative in a variety of disorders affecting the peripheral nervous system. Muscle Nerve 56: 819-822, 2017., (© 2017 Wiley Periodicals, Inc.)

Objectives: The primary objective was to investigate the effects of continuous typing on median nerve changes at the carpal tunnel region at two different keyboard slopes (0° and 20°). The secondary objective was to investigate the differences in wrist kinematics and the changes in wrist anthropometric measurements when typing at the two different keyboard slopes., Methods: Fifteen healthy right-handed young men were recruited. A randomized sequence of the conditions (control, typing I, and typing II) was assigned to each participant. Wrist anthropometric measurements, wrist kinematics data collection and ultrasound examination to the median nerve was performed at designated time block., Results: Typing activity and time block do not cause significant changes to the wrist anthropometric measurements. The wrist measurements remained similar across all the time blocks in the three conditions. Subsequently, the wrist extensions and ulnar deviations were significantly higher in both the typing I and typing II conditions than in the control condition for both wrists (p<0.05). Additionally, the median nerve cross-sectional area (MNCSA) significantly increased in both the typing I and typing II conditions after the typing task than before the typing task. The MNCSA significantly decreased in the recovery phase after the typing task., Conclusions: This study demonstrated the immediate changes in the median nerve after continuous keyboard typing. Changes in the median nerve were greater during typing using a keyboard tilted at 20° than during typing using a keyboard tilted at 0°. The main findings suggest wrist posture near to neutral position caused lower changes of the median nerve.

During grasping, the median nerve undergoes mechanical stress in the carpal tunnel which may contribute to carpal tunnel syndrome. This study investigated the effects of wrist posture, grip type, and grip force on the shape and cross-sectional area of the median nerve. Ultrasound examination was used to obtain cross-sectional images of the dominant wrist of 16 healthy subjects (8 male) at the proximal carpal tunnel during grasping. The cross-sectional area, circularity, and axis lengths of the median nerve were assessed in 27 different conditions (3 postures × 3 grip types × 3 force levels). There were no significant changes in median nerve cross-sectional area (P > 0.05). There were significant interactions across posture, grip type, and grip force affecting nerve circularity and axis lengths. When the wrist was flexed, increasing grip force caused the median nerve to shorten in the mediolateral direction and lengthen in the anteroposterior direction (P < 0.04), becoming more circular. These effects were significant during four finger pinch grip and chuck grip (P < 0.05) but not key grip (P > 0.07). With the wrist extended, the nerve became more flattened (less circular) as grip force increased during four finger pinch grip and chuck grip (P < 0.04) but not key grip (P > 0.3). Circularity was lower during the four finger pinch compared to chuck or key grip (P < 0.03). The findings suggest that grip type and wrist posture significantly alter the shape of the median nerve. Clin. Anat. 30:470-478, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

Background: Carpal tunnel syndrome (CTS) is a musculoskeletal condition that often impairs the fitness to work. Our aim is to retrospectively evaluate the association between physical exposures in meat processing industry in Northern Italy and the CTS, taking into account non-occupational factors., Material and Methods: A cross-sectional study was performed to include 434 workers (236 males, 198 females, 37.0±10.6 years old, working age: 12.6±10.8 years) from meat processing industries. Signs and symptoms were collected at the compulsory occupational medical surveillance. Occupational risk factors were assessed through a questionnaire and direct assessment by investigators. Adjusted odds ratios (OR adj ) for factors of interest were estimated through binary logistic regression., Results: Diagnosis of the CTS was reported for 61 out of 434 subjects (14.1%) for an incidence of 11.3/1000 person- years. In general, signs and symptoms for the CTS were associated with the following demographic factors: smoking history (OR = 1.909, 95% confidence interval (CI): 1.107-3.293), previous traumas of the upper limb (OR = 3.533, 95% CI: 1.743-7.165), hypothyroidism status (OR = 7.897, 95% CI: 2.917-21.38) and, in the case of female participants only, previous pregnancies (OR = 2.807, 95% CI: 1.200-6.566) as well as a personal history of oral contraceptive therapy and/or steroidal replacement therapy (OR = 11.57, 95% CI: 4.689-28.56). The carpal tunnel syndrome cases were associated with the following occupational factors (> 4 h/day): forceful hand exertion (OR adj = 3.548, 95% CI: 1.379-9.131), repeated trauma of the hand (OR adj = 3.602, 95% CI: 1.248- 10.395), repeated movements of the wrist (OR adj = 2.561, 95% CI: 1.100-5.960)., Conclusions: Increasing levels of hand activity and force were associated with the increased CTS prevalence among participants. Recommendations have to be provided in order to reduce occupational exposure to these risk factors and improve medical surveillance. Med Pr 2017;68(2):199-209., (This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.)

Background: Forceful, high-velocity, and repetitive manual hand tasks contribute to the onset of carpal tunnel syndrome. This study aimed to isolate and identify mechanisms that contribute to tendon gliding resistance in the carpal tunnel., Methods: Eight human cadaver hands (four pairs) were used. Tendon gliding resistance (force, energy, and stiffness) was measured under different conditions: with intact and with divided subsynovial connective tissue, at 2mm/s and 60mm/s tendon excursion velocity, and with and without relaxation time before tendon excursion., Results: Subsynovial connective tissue stretching substantially contributed to increased gliding resistance force and energy during higher tendon excursion velocities, and subsynovial connective tissue stiffening was observed. Poroelastic properties of the tendon (and possibly the subsynovial connective tissue) also appear to be involved because relaxation time significantly increased gliding resistance force and energy (P<0.01), and the difference in energy and force between high- and low-velocity tendon excursions increased with relaxation time (P=0.01 and P<0.01). Lastly, without relaxation time, no difference in force and energy was observed (P=0.06 and P=0.60), suggesting contact friction., Interpretation: These findings are consistent with the hypothesis that the mechanics of tendon motion within the carpal tunnel are affected by the integrity of the subsynovial connective tissue. While not tested here, in carpal tunnel syndrome this tissue is known to be the fibrotic, thickened, and less-fluid-permeable. An extrapolation of our findings suggests that these changes in the subsynovial connective tissue of carpal tunnel syndrome patients could increase contact friction and carpal tunnel pressure., Competing Interests: The authors have no conflicts of interest to declare., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

We quantified intraneural blood flow (INBF) using perfusion measurement software (PixelFlux), and compared it with the qualitative method of counting blood vessels (vessel score) in a cohort of carpal tunnel syndrome (CTS) patients., Methods: Forty-seven patients (67 wrists) with a clinical and electrophysiological diagnosis of CTS, and 20 healthy controls (40 wrists) were enrolled. Median nerve ultrasound (US) was performed at the carpal tunnel inlet to measure the cross-sectional area (CSA) and vessel score. Power Doppler sonograms from nerves with detectable INBF were processed with PixelFlux to obtain the maximum perfusion intensity (MPI)., Results: Forty-nine percent of CTS patients had detectable INBF compared with none in the control group (P < 0.0001). MPI correlated significantly with vessel score (r = 0.945, P < 0.0001), CSA (r = 0.613, P < 0.0001), and electrophysiological severity (r = 0.440, P < 0.0001). MPI had higher intra- or interobserver reliability compared with vessel score (0.95 vs. 0.47)., Conclusion: MPI is a better method for quantification of INBF. Muscle Nerve, 2016 Muscle Nerve 55: 77-83, 2017., (© 2016 Wiley Periodicals, Inc.)

Background: Carpal tunnel syndrome is treated successfully by surgical release of the transverse carpal ligament (TCL). However, persistent weakness of grip and pain over the thenar and hypothenar ends of this ligament, and "pillar pain", are reported to be common complications. In order to reduce these complications, different ligament reconstruction or lengthening techniques have been proposed., Objective: The purpose of this study is compare effectiveness and complications of TCL z-lengthening technique with complete TCL section., Methods: A prospective, randomised, intervention trial was conducted on 80 patients. The patients were divided into 2 groups: 1) complete release of TCL; 2) z-lengthening of TCL according to a modified Simonetta technique. Grip strength, pillar pain and clinical and functional assessment were carried out using the Levine et al. questionnaire., Results: No significant differences were observed (p>.05) in the postoperative reviews between the two groups as regards grip strength loss and pillar pain. There were significant differences between preoperative and postoperative mean Levine scores, but there was no difference in the mean scores of the two procedures at any time., Discussion: In conclusion, according to the results, TCL z-lengthening is more effective than simple division, but there is no identifiable benefit in z-lengthening for avoiding complications., (Copyright © 2016 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.)

Introduction: Carpal tunnel syndrome (CTS) is a prevalent upper limb condition that results in significant individual and socioeconomic costs. Large patient numbers, long outpatient waiting times and traditional referral pathways in public health systems create delays in accessing treatment for this condition. Alternative care pathways aimed at streamlining access to treatment and reducing the need for surgical intervention warrant further investigation., Methods: A randomised, single-blind controlled clinical trial will be conducted. 128 participants aged 18-75 years with CTS will be recruited from the carpal tunnel surgery waitlists of participating public hospitals. Suitable participants will be stratified for severity and randomly allocated to either receive therapy (education, provision of splints and a home exercise programme) or standard care (continuing on the waitlist without hand therapy intervention for the duration of the study). Outcomes will be measured at baseline and after 6 weeks and 6 months. Primary outcomes are conversion to surgery ratio and perceived effect via the Global Rating of Change Scale.Secondary measures include patient satisfaction, and monitoring of symptoms and function using outcome measures including the Boston CTS Questionnaire, Disability of Arm, Shoulder and Hand Questionnaire, Patient-Specific Functional Scale, patient completed diagram of symptoms and Self-reported Leeds Assessment of Neuropathic Symptoms and Signs pain scale., Discussion: This paper outlines the design and rationale for a randomised controlled trial that aims to assess the efficacy of an alternative care pathway for the management of patients with CTS while on the surgery waitlist. It is anticipated that the outcomes of this study will contribute to improved and expedited management of this common condition in a public hospital setting., Ethics and Dissemination: Ethics approval was granted by the Princess Alexandra Hospital Centres for Health Research (HREC/13/QPAH/434-SSA/13/QPAH/447) and the Medical Research Ethics Committee at the University of Queensland. Results will be disseminated via conferences and peer-reviewed publications., Trial Registration Number: ACTRN12613001095752., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Objective: To Verify the value of the ratio of sensory nerves conductive velocity along palm-median finger /wrist-palm minus 1 for diagnosis of the mild-moderate carpal tunnel syndrome(CTS)., Methods: The different value between 1 and the ratio of sensory nerves conductive velocity along palm-median finger/wrist-palm was defined as index-CTS which was used to assess the severity of CTS.The index-CTS of 100 palms from healthy controls and 58 palms from mild-moderate CTS patients were calculated and compared.Multiple regression was used to identify the relative factors of index-CTS.The ROC curve was used to evaluate the sensitivity and specificity of index-CTS at different values., Results: The value of index-CTS from healthy controls and patients both fitted Gaussian distribution.The mean value were -0.053±0.042 vs 0.055±0.074 in the controls and the patients respectively.The difference was statistically significant between the two groups by T-test(P<0.001). Multiple regression analysis showed that Tinel sign, Phalen sign, laterality, clinical grade, electrical grade were identifiable factors related to index-CTS.When index-CTS was over 0.001 and Ⅳ-DL over 0.395 ms , specificity of diagnosis by both can get 92%, but index-CTS showed more higher sensitivity(98.3% vs 89.7%)., Conclusions: Rising index-CTS could be the most significant electrophysiological feature in CTS.It can be used as a sensitive marker to assess the extent of conduction block of median nerve in carpal tunnel.

Purpose: High-resolution ultrasound is increasingly used in the diagnosis of carpal tunnel syndrome; yet little is known about gender differences in clinical presentation and ultrasound findings., Materials and Methods: In this high-resolution ultrasound-based retrospective study in 170 cases, we assessed gender influence in CTS in terms of the severity of neural alterations by wrist-to-forearm ratio (WFR), epineural thickening, loss of fascicular anatomy, as well as classical signs and symptoms. The control group consisted of 42 wrists., Results: Women present with a greater WFR at first admission are affected more often bilaterally, and report less subjective pain intensity, while men report fewer nightly pain episodes at higher WFR. Loss of fascicular anatomy is three times more frequent in women. An increase in epineural thickness, loss of fascicular anatomy, and involvement of more than 1.5 fingers correlate significantly with WFR regardless of sex., Conclusion: Women differ significantly from men in terms of clinical presentation and ultrasound findings upon first diagnosis of CTS, which should be included in further diagnostic considerations.

Introduction: G1 electrode placement at the distal wrist crease during the median orthodromic palmar nerve conduction study (NCS) could result in a false negative study if compression is more proximal., Methods: In this study we aimed to determine the effect of median G1 electrode placement on distal latencies and amplitudes. Methods Median orthodromic palmar NCS was performed with the G1 electrode at the wrist crease and 2 cm proximal, stimulating 8 cm distal to G1. The difference in the distal latencies and amplitudes between the 2 recording sites was calculated., Results: In 26 controls and 25 carpal tunnel syndrome (CTS) patients, the mean proximal-distal latency difference and percent amplitude decrease (distal vs. proximal) was -0.085 ms/53% (controls) and -0.072 ms/45% (CTS)., Conclusion: Distal latency is not significantly affected by G1 placement in the median orthodromic palmar NCS, but the amplitudes are nearly twice as high when G1 is placed 2 cm proximal to the wrist crease., (© 2015 Wiley Periodicals, Inc.)

Carpal tunnel syndrome (CTS) may be caused by subclinical tenosynovitis which may be detected by ultrasonography (US). The objective of this study is to investigate whether ultrasonography has a place in the workup of idiopathic CTS patients. Therefore, we investigated the prevalence of tenosynovitis and its association with the clinical outcome of surgery. A cohort of 31 consecutive idiopathic CTS patients (33 wrists) who were a candidate for carpal tunnel release (CTR) surgery was assessed using greyscale ultrasonography (GSUS) and power Doppler ultrasonography (PDUS). Peroperatively, tenosynovitis was evaluated macroscopically by the surgeon. Tissue samples from areas macroscopically suspected for tenosynovitis were taken for histological evaluation. The clinical outcome of the operation was assessed after 6 months and if applicable alternative diagnoses for the CTS were proposed. US tenosynovitis (OMERACT) was detected preoperatively in 58 % of the wrists. Peroperatively, macroscopic tenosynovitis was detected visually in 88 % of the wrists. Histological evaluation demonstrated a limited influx of lymphocytes indicative of a mild chronic inflammatory response in 19 %. Non-specific reactive changes were observed in 78 % of the cases. Ultrasonographically defined tenosynovitis was associated with an OR of 2.81 (95 % CI 0.61-13) for responding well to surgery. Most cases of ultrasonographic and peroperatively defined tenosynovitis were classified by histology as reactive changes. The presence of ultrasonographic tenosynovitis might be associated with a better clinical outcome of surgery.

Objective: To evaluate median nerve excursion during conventional nerve gliding exercises and newly developed exercises, primarily comprising abduction and adduction of the fingers., Design: Descriptive study., Setting: Anatomical dissection facility., Cadavers: Random sample of upper extremities of fresh whole-body human cadavers (N=18). Cadavers with neuromuscular diseases in the medical record or anatomic variations were excluded., Intervention: Conventional and new nerve gliding exercises., Main Outcome Measures: Distances between markers applied into the nerve and markers in the periosteum were visualized with ultrasound and measured. Comparisons of nerve excursions between different exercises were performed., Results: Conventional exercises led to substantial nerve gliding proximal to the carpal tunnel and between the head of the pronator teres (12 and 13.8mm, respectively), but it led to far less in the carpal tunnel (6.6mm). With our novel exercises, we achieved nerve gliding in the carpal tunnel of 13.8mm. No substantial marker movement could be detected during lateral flexion of the cervical spine., Conclusions: Although conventional nerve gliding exercises only lead to minimal nerve excursions in the carpal tunnel, our novel exercises with the abduction and adduction of the fingers result in substantial longitudinal gliding throughout the arm. Clinical trials will have to deliver the clinical evidence., (Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine the interrater and intra-rater reliability of ultrasound (US) measurement of the cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet., Methods: Three examiners of varying levels of experience performed US measurements of the CSA of the median nerve at the carpal tunnel inlet of both wrists of 11 healthy volunteers. Each examiner was blinded to the measurements of the other examiners. The measurements were repeated 2 weeks later in random order to test intra-rater reliability. The Lin concordance correlation coefficient (LCCC) for interrater and intra-rater reliability was calculated., Results: The overall inter-rater LCCC was 0.59 (95% confidence interval [CI], 0.41-0.73). Intra-rater LCCC varied based on examiner experience. The senior author had an intra-rater LCCC of 0.91 (95% CI, 0.80-0.96), the hand fellow had an intra-rater LCCC of 0.45 (95% CI, 0.17-0.66), and the first-year resident had an intra-rater LCCC of 0.78 (95% CI, 0.55-0.90)., Conclusions: There is moderate agreement among examiners of varying levels of experience when measuring the CSA of the median nerve at the carpal tunnel inlet. Examiner experience affected intra-rater reliability of measurements; an experienced examiner had nearly perfect agreement compared with moderate agreement for less experienced examiners., (Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.)

Background: The carpal tunnel is a fibro-osseous structure containing the median nerve and flexor tendons. Its cross-sectional area has been shown to increase during compressive force application to the carpal bones in modeling and in vitro studies. The purpose of this study was to investigate the morphological and positional changes of the carpal arch and median nerve while in vivo compressive force was applied in the radioulnar direction across the wrist., Methods: Ultrasound images of the carpal tunnel and its contents were captured for 11 healthy, female volunteers at the distal tunnel level prior to force application and during force application of 10 and 20N., Findings: With applied force, the carpal arch width significantly decreased, while the carpal arch height and area significantly increased (P<0.001). The median nerve shape became more rounded as the compressive force magnitude increased, reflected by decreases in the nerve's flattening ratio and increases in its circularity (P<0.001). The applied force also resulted in nerve displacement in the radial-volar direction., Interpretation: This study demonstrates that noninvasively applying radioulnar compressive force across the wrist may potentially provide relief of median nerve compression to patients suffering from carpal tunnel syndrome., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Introduction: We evaluated the electrodiagnostic (EDX) pattern of severe and extreme median nerve lesions at the wrist (MNLW) in patients with idiopathic carpal tunnel syndrome., Methods: EDX data were recorded in 229 patients with 314 severe and extreme MNLW and 447 patients with 777 non-severe MNLW. We recorded distal motor latency (DML) to abductor pollicis brevis (APB) and second lumbricalis (2L), sensory conduction (SC) from digits 2 and 3, and needle examination of APB., Results: Preservation rate of DML to APB and 2L and of SC from digits 2 and 3 were 100%, 100%, 85%, and 76%, respectively, for severe MNLW, and 37%, 90%, 36%, and 26% for extreme MNLW. Active denervation, as demonstrated by fibrillation potentials, was found in 1% of non-severe NMLW, 7% of severe MNLW, and 56% of extreme MNLW cases., Conclusions: In idiopathic severe and extreme MNLW, the DML to the 2L and averaged SC from digit 2 can be present when other responses are absent., (© 2014 Wiley Periodicals, Inc.)

Carpal tunnel syndrome, in its idiopathic form, is an extremely common entrapment neuropathy in the clinical practice however secondary compressive causes are rare. Among secondary causes, tumors are even rarer. Although lipomas are the most common soft tissue tumor in the body, <5% of the benign tumors of the hand are lipomas. A 48-year old manual laborer man presented to us with a two-year history of numbness, tingling and burning pain in the palmar surface of the left hand and fingers along with a progressively increasing swelling in the hand and wrist. His medical history was unremarkable and no trauma episode was reported. According to the clinical examination and the result of median nerve conduction study (NCS) the diagnosis of carpal tunnel syndrome was established. Operative release of the transverse carpal ligament was subsequently performed along with excision of the lipoma using extensile open approach. Intraoperatively, median nerve and its digital branches were found to be stretched over the giant lipoma causing substantial compression to median nerve. Histopathological findings of the resected mass were consistent with lipoma. After two years the patient was pain-free without any sign of tumor recurrence. Lipomas are infrequently seen in hand and wrist, however giant lipoma as a cause of secondary carpal tunnel syndrome is even more rare, which makes this case interesting.