Median Nerve In Carpal Tunnel Research Articles

Diagnostic value of diffusion-weighted MRI using apparent diffusion coefficient (ADC) in evaluation of median nerve in carpal tunnel syndrome

BackgroundThe diagnosis of carpal tunnel syndrome is based on a combination of clinical history, clinical examination and frequent use of electrodiagnostics as nerve conduction study and electromyography which often do not provide the spatial and anatomical localizing information, especially with small nerves of the extremities. Conventional magnetic resonance imaging can reveal morphological changes in carpal tunnel syndrome patients.AimThe purpose of our study was to assess the efficacy of diffusion magnetic resonance imaging as a functional imaging in evaluation of median nerve in carpal tunnel syndrome.Patients and methodsThis prospective study included a group of 33 patients with carpal tunnel syndrome diagnosed by both clinical examination and electromyography; 40 writs were examined. A control group of 20 subjects of matched age group were also included. All the participants were subjected to conventional and diffusion magnetic resonance imaging studies.ResultsMedian nerve apparent diffusion coefficient values of patients are lower than those of controls. The sensitivity and diagnostic accuracy of diffusion conventional magnetic resonance imaging were 95% and 97.5%, respectively, versus 25% and 62.5% of conventional magnetic resonance imaging. A cut-off apparent diffusion coefficient value ≤ 0.99 obtained at distal radio-ulnar joint level and > 1.07 at pisiform level as well as apparent diffusion coefficient ratio at a cut-off ≤ 0.2 was significantly valid for diagnosing carpal tunnel syndrome.ConclusionsDiffusion magnetic resonance imaging provides functional evaluation of median nerve in patients with carpal tunnel syndrome.

RELATIONSHIP BETWEEN CLINICAL FINDINGS OF CARPAL TUNNEL SYNDROME WITH ENMG AND USG WRIST RESULT

Background: Carpal tunnel syndrome is symptomatic compression neuropathy of median nerve in carpal tunnel on wrist causes functional decreased in that area. CTS is diagnosed from clinical, physical examination, also from ENMG and USG wrist. This research aims to know about CTS characteristics and the relationship between clinical findings of CTS with ENMG and USG wrist results. Objective: This study aims to determine whether there is a relationship between the clinical findings of patients diagnosed with CTS and the results of ENMG and wrist ultrasound at the Neurology Polyclinic of Saiful Anwar Hospital, Malang. Methods: This research was descriptive observational. Data were collected from anamnesis and physical examination at Neurology Polyclinic Saiful Anwar Malang Hospital (RSSA) from April to December 2017, then examined by ENMG and USG wrist at RSSA. There are 27 patients suspected of CTS who meet inclusion and exclusion criteria. Results: From 9 months (April-December 2017) found 27 patients suspected CTS, about 19 patients (70,37%) were female and 7 patients (19,63%) were male. The majority of the age group is 25-65 years old (66,67%). Most of the occupations were housewives (48,15%). Patients most came with chief complaint of tingling (88,89%) with positive tinnel sign (77,78%), and most concomitant diseases were hypertension (48,15%). The ENMG results confirmed CTS about 92,59%, compared to the USG that confirmed CTS about 85,19%. Statistical analysis with Pearson Chi-Square test showed no relationship between clinical findings of CTS (Tinnel, Phalen, Counter Phalen, Flick test) with ENMG and USG wrist results. Conclusion: This research concluded no relationship between clinical findings of CTS with ENMG and USG wrist results.

The cross-sectional morphology of median nerve in carpal tunnel of healthy, adult population: A systematic review and meta-analysis

The full text of manuscripts were collected after short-listing the abstracts collected from search strategy. A quality assurance tool was used to capture the risk of bias of each study after reviewing the included manuscripts. The pooled estimate of cross-section area was stratified according to anatomical landmarks, sex, and ancestry. A total of 97 observational studies dealt with 6679 wrists of healthy subjects were included. The pooled estimate of the cross-section area of median nerve at carpal tunnel inlet was 8.54mm2 [95% CI: 8.34-8.74mm2]. The same pooled estimate at carpal tunnel outlet was 8.03mm2 [95% CI: 7.46-8.60mm2]. Both these pooled estimates have significant correlation with mean age of population. Age and sex were two primary predictors of the cross-section of median nerve. The flattening ratio, circularity, and wrist-forearm ratio of median nerve were also computed. These normative data could serve as a reference for assessing median nerve pathologies, including carpal tunnel syndrome. The ethnic variation of pooled estimate and heterogeneity will guide clinician set up the reference value for diagnostic criteria.

Body mass index: A modifying factor of median nerve conduction

Background: Nerve conduction studies are important electrophysiological tests used to assess functional status of peripheral nerves. Entrapment of median nerve in carpal tunnel is a possibility in high body mass index (BMI). Aim and Objectives: The objective of this study was to determine BMI as a modifying factor of median nerve conduction. Materials and Methods: Forty-seven healthy male subjects were divided in three study groups, that is, normal, pre-obese, and obese according to BMI. Nerve conduction study was tested to compare different parameters of compound motor action potential (CMAP) and sensory nerve action potential (SNAP). Parameters used for SNAP were peak latency (PL), conduction velocity (CV), and amplitude (Amp). Parameters used for CMAP were distal motor latency (DML), CV, and amplitude (Amp). Results: In the right median nerve, CMAP between various groups represented significant prolongation of DML (P = 0.000) and slowing CV (P = 0.000) with increasing BMI. In the left median nerve, CMAP between various groups represented significant prolongation of DML (P = 0.000) and slowing CV (P = 0.000) with increasing BMI. In the right median nerve, SNAP between various groups represented significant prolongation of PL (P = 0.000) and slowing CV (P = 0.000) with increasing BMI. In the left median nerve, SNAP between various groups represented significant prolongation of PL (P = 0.000) and slowing CV (P = 0.000) with increasing BMI. Conclusion: Our study suggested BMI as the substantial factor to affect median nerve conduction at carpal tunnel. Thus, high BMI plays crucial role to develop carpal tunnel syndrome (CTS).

TENS and Acupuncture in treatment of Carpal Tunnel Syndrome

Aim: To compare efficacy of transcutaneous electro neuron stimulation (TENS) of median nerves and acupuncture in the treatment of carpal tunnel syndrome (CTS) Materials and methods: The study included 138patients with a diagnosis of CTS. 30patients received only pharmacotherapy treatment. 36patients received an additional course of high-frequency lowamplitude (HL) TENS, 38 patients a course of low-frequency highamplitude (LH) TENS and 34patients a course of acupuncture. Observed responses to the treatment in study using Pain VAS, Tinel’s and Phalen’s Signs and electromyography of median nerves. Results: Greater reduction of pain and Tinel’s and Phalen’s signs was determined in the application of TENS and acupuncture combined with pharmacotherapy. More significant reduction of pain was noted by HL TENS compared with LH TENS and acupuncture. Intensity of positive Tinel’s and Phalen’s signs was significantly lower with LH TENS and acupuncture compared with HL TENS. The electroneuromyography indicators (Amplitude and latency M-response and velocity of sensory fibres), have improved on the background of the LH TENS and at least after acupuncture (p<0.05). Conclusion: Based on the results of this study TENS and acupuncture enhance efficiency of pharmacotherapy in treatment of CTS reducing the severity of sensory and motor clinical and EMG manifestations of the CTS. Spontaneous pain more decrease by HL TENS. Compression of the median nerve in carpal tunnel more reduced following LH TENS and acupuncture. Significant regression of EMG disorders of median nerve was noted by LH TENS therapy.

Hand Function among Patients with Carpal Tunnel Syndrome

Background: Carpal Tunnel Syndrome (CTS) is the compression of the median nerve in carpal tunnel of wrist which leads to the typical symptoms of numbness, paresthesia and sometimes pain in the patient’s hand. The symptoms are usually sensed in the first three radial fingers and the lateral side of the ring finger because these areas are innervated by the median nerve. Objective: To assess hand function among patient with Carpal Tunnel Syndrome (CTS). Methods: This was a descriptive study in which 41 subjects (27 females and 14 males) were included from Ghurki trust teaching hospital, Lahore and Shalamar hospital, Lahore (from August 2018 to October 2018) according to inclusion criteria. Samples were collected according to WHO (World Health Organization) calculator. Hand function was measured with Boston Carpal Tunnel Questionnaire (BCTQ). Results: Majority of the patients with CTS fell into mild functional severity and mild symptom severity. The mean score for functional severity was 2.34 and for symptom severity it was 2.97. Conclusion: Activities of daily living such as grasping, writing, gripping and carrying objects were affected by the symptoms of pain, numbness, tingling and weakness in the patients suffering from CTS.

Comparison course of pregnancy related carpal tunnel syndrome in breastfeeding and non-breastfeeding women during the first 6 months after delivery

Entrapment of median nerve in carpal tunnel is called carpal tunnel syndrome (CTS). The main purpose of this research is to compare the natural course of the syndrome during the first 6 months after delivery in the women feeding their children using formula and breastfeeding mothers. The present research was done in 50 pregnant women with symptoms and signs of CTS visited by obstetricians and then referred to physiatrist for electrodiagnostic studies. After delivery and confirming the CTS, women classified in two groups: breastfeeding (33) and non-breastfeeding (17) women. The 5 breastfeeding women missed from study. Follow-up of clinical and electrodiagnostic of women were done in first 6 months after delivery. Complete recovery in breastfeeding, non-breastfeeding and all women were10.7%, 52.9% and 26.7%, respectively. Partial recovery in breastfeeding and non-breastfeeding women was 71.4% and 47%, respectively. Complete recovery in mild stage in breastfeeding, non-breastfeeding and all women were 22.2%, 57.1% and 33.3%, respectively. Complete recovery in moderate and severe stages in all women were 23.3%. Rate of complete recovery to partial recovery in non-breastfeeding women was 1.7 times than breastfeeding women. This study was showed the relief of symptoms and reduction of severity of CTS in the women who feed their children on formula is higher than those who breastfeed their children. Pregnancy related CTS would not usually resolve after delivery and must be follow-up by clinical symptoms and electrodiagnostic studies. Hormonal changes during lactation and repetitive motions and/or excessively flexed wrist positions during breastfeeding may be causing aggravated pregnancy related CTS after delivery.

Effectiveness of wrist tube inside and outside releasing for treating median nerve double entrapment at wrist

To investigate the effectiveness of wrist tube inside and outside releasing for treating median nerve double entrapment at wrist. Thirty-one patients of median nerve double entrapment at wrist were treated between April 2011 and May 2014. There were 8 males and 23 females with an age of 33-69 years (mean, 56.4 years). In palm lateral three and a half finger, the two-point discrimination was 7-14 mm (mean, 9.5 mm), in which 24 cases were 4-10 mm and 7 cases were more than 10 mm. Carpal tunnel median nerve Tinel sign was positive; there was weak and acid swollen felling when press big thenar muscle on median nerve return branch palm surface projection points. Electromyography examination showed that median nerve endings movement incubation period was 4.5-10 ms in 22 cases, more than 10 ms in 9 cases; fibrillation potentials and positive phase voltage happened in 6 cases; the median nerve sensory conduction velocity of all patients was slow, and the motor conduction velocity also slowed down; the motor amplitude was 5-10 mV in 19 cases, less than 5 mV in 12 cases. The disease duration was 3-8 months (mean, 5.5 months). Surgical exploration of wrist median nerve in carpal tunnel and median nerve return branch outside carpal tunnel were performed in patients, especially completely released the variety entrapment factors such as thickening bow at starting point of short hallux flexor tendon, fiber bundles at ulnar side of short hallux flexor tendon, deep layer fiber of the palmar aponeurosis, and variant shallow head of short hallux flexor. All the wounds healed by first intention without wound scar pain. The patients were followed up 24-59 months (mean, 33 months). Night numbness and pain disappeared, and weak and acid swollen feeling in big thenar muscle on median nerve return branch points also disappeared. The sensation recovered to S 4 in 28 patients in palm lateral three and a half finger, the index and middle fingertip sensation recovered to S3+ in 3 cases. In the median nerve innervation area, the two points discrimination was 4-6 mm (mean, 4.8 mm). The thumb opposition function returned to normal in 29 cases and mild confinement in 2 cases. The grip strength of all the 31 cases recovered, and 1 of them increased significantly. In preoperative big thenar muscle atrophy cases, muscle strength recovered to S 5 in 4 cases, S 4 in 2 cases. At 2 years after operation, according to the functional assessment of carpal tunnel syndrome recommend by GU Yudong, the results were excellent in 29 cases and good in 2 cases, with an excellent and good rate of 100%. When treating the nerve double entrapment in wrist using wrist tube inside and outside releasing method, the variety entrapment factors of return branch of median nerve should be completely released, so the effectiveness can be improved.

Value of ratio of sensory nerves conductive velocity along palm-median finger/wrist-palm in diagnosing the carpal tunnel syndrome

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). 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. 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%). 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.

Carpal tunnel syndrome: Ultrasonographic evaluation of median nerve diameter

Background: Carpal tunnel syndrome is the most frequently encountered peripheral compression neuropathy. Diagnosis of carpal tunnel syndrome involves physical examination, nerve conduction studies and electromyography. Ultrasonography (USG) examination of median nerve in carpal tunnel has been proposed as a useful alternative in diagnosing carpal tunnel syndrome. Materials and Methods: Patients were selected from those undergoing diagnostic workup for carpal tunnel syndrome in pre-treatment period. USG was performed using 11 MHz linear array transducer. Cross-sectional area at each level, major and minor axes were measured. Results: In our study, the mean median nerve cross sectional area at proximal part of carpal tunnel by direct method was 12.33 mm 2 in patients and 7.33 mm 2 in controls. By indirect method it was 12.01 mm 2 and 6.633 mm 2 in cases and controls respectively. In this study we found significant difference in flattening ratio between cases and controls. The mean flattening ratio in distal part of tunnel (at the level of hook of hamate) was 2.97 and 2.38 in cases and controls respectively. The sensitivity and specificity for cut-off value ≥2.5 was 76% and 63% respectively. Conclusion: We found that best discriminatory criterion for diagnosis of carpal tunnel syndrome are median nerve cross sectional area in the proximal part of carpal tunnel ≥9 mm 2 (Direct method) and ≥8.5 mm 2 (Indirect method). With our experience, we found it easier to evaluate the median nerve in the carpal tunnel in the disto proximal sequence by identifying the flexor pollicislongus (FPL) first with dynamic evaluation. As the percentage of space occupying lesions causing symptoms in unilateral (atypical) carpal tunnel syndrome is 35%, we highly recommend this pre-operative investigation in all carpal tunnel syndrome patients.

Correlation of Nerve Ultrasound, Electrophysiological and Clinical Findings in Chronic Inflammatory Demyelinating Polyneuropathy

We present the nerve ultrasound findings in chronic inflammatory demyelinating polyneuropathy (CIDP) and examine their correlation with electrophysiology and functional disability. A total of 75 healthy controls and 48 CIDP patients underwent clinical, sonographic and electrophysiological evaluation a mean of 3.9 years(SD+/-2.7) after disease onset. Nerve ultrasound revealed statistically significant higher cross-sectional area (CSA) values of the median (P<.0001), ulnar (P<.0001), radial (P<.0001), tibial (P<.0001), fibular nerve(P<.0001) in most of the anatomic sites and brachial plexus (supraclavicular, P<.0001;interscalene space, P = .0118),when compared to controls. The electroneurography documented signs of permanent axonal loss in the majority of peripheral nerves. A correlation between sonographic and electrophysiological findings was found only between the motor conduction velocity and CSA of the tibial nerve at the ankle (r = -.451, P = .007). Neither nerve sonography nor electrophysiology correlated with functional disability. The CSA of the median nerve in carpal tunnel and the ulnar nerve in Guyon's canal correlated with disease duration (P = .036, P = .027 respectively). CIDP seems to show inhomogenous CSA enlargement in brachial plexus and peripheral nerves, with weak correlation to electrophysiological findings. Neither nerve sonography nor electrophysiology correlated with functional disability in CIDP patients. Multicenter, prospective studies are required to proof the applicability and diagnostic values of these findings.

Giant median nerve in bilateral carpal tunnel syndrome

We introduce a middle age healthy man with sequential bilateral carpal tunnel syndrome. At the surgery, we encountered a wide median nerve in both wrists. Although enlargement of median nerve in carpal tunnel has been well documented, 25 mm width of the nerve is a rare scene, underscoring that leaving the nerve under the unyielding pressure would lead to a fibrous atrophic median nerve.

Sonographic appearance and clinical significance of anatomic variation of carpal tunnel median nerve

Objective To investigate the incidence,sonographic appearance of the anatomic variation of carpal tunnel median nerve and its accompanying structures in healthy volunteers and explore the value of this variation in carpal tunnel syndrome.Methods A total of 360 hands of 180 healthy volunteers were included in the study.The full course of the median nerve in the forearm and carpal tunnel was examined with high-frequency ultrasound.The median nerve was first located in cross section at wrist and then with continuous cross-sectional scanning to observe the the full course of the median nerve in the forearm and carpal tunnel with high-frequency ultrasound.Results Anatomic variation of carpal tunnel median nerve and its accompanying structures were observed:① High division median nerve were found in 2 wrists (0.56 ％) ;②Bifid median nerve were found in 17 wrists (4.72％) ;③Persistent median artery were found in 22 wrists (6.11％),and 2 wrists (0.56％) were also found accompanied vein.Aanatomic variation of carpal tunnel median nerve accompanied with persistent median artery were observed in 16 wrists (4.44 ％).Conclusions High-frequency ultrasound was sensitive to diagnose the anatomic variation of carpal tunnel median nerve and its accompanying structures.Recognition of these variations can help us to make correct diagnosis of carpal tunnel syndrome. Key words: Ultrasonography; Median nerve; Carpal tunnel syndrome

Comparison Efficacy of Triamcinolone and Wrist Splint in Severe Carpal Tunnel Syndrome in Pregnancy

Introduction: Carpal tunnel syndrome (CTS) is entrapment of median nerve in carpal tunnel of the wrist. The main aim of this study was to compare the effectiveness of steroid injection and wrist splint in severe carpal tunnel syndrome in pregnancy. The cases were selected among pregnant women who referred to OB and GYN clinic in Yasuj city in South- west of Iran. Materials and methods: This study is a randomized clinical trial which was accomplished from December 2010 to June 2012 at S. Mofateh Clinic on 28 pregnant women. Standard electrodiagnostic techniques were performed on the women who had clinical symptoms of CTS in their hands, with positive Tinel and/or Phalen tests, for rule in/or out of CTS. The patients with severe CTS were randomly divided in 2 groups including triamcinolone injection (40 mg) and wrist splint in night for 6 weeks. Electrophysiologic parameters of median and ulnar nerves were recorded before and 2 months after the steroid injection and wrist splint. In cases of observing changes from severe to lower stages of the disease in electrodiagnostic studies, treatment was considered successful and otherwise failed. Results: Effectiveness of triamcinolone injection and wrist splint were 85. 7% and 90. 9%, respectively. There was no significant difference between treatments by steroid injection and wrist splint (p=0. 157). Also no correlation was observed between severe carpal tunnel syndrome and number of pregnancy. Conclusion: Triamcinolone injection or wrist splint are effective methods for treatment of severe CTS in pregnancy and therefore recommended instead of carpal tunnel release surgery.

Variations of Median Nerve in Carpal Tunnel and its Distribution in Hand

Aim of the study was to study the variations in the branching pattern of median nerve in the carpal tunnel and hand, which would form useful data for hand surgeons doing open/endoscopic carpal tunnel release. Median nerve and its branches were explored by dissection in fifty hands of twenty-five formalin fixed adult human cadavers over a period of three years. We found variations in 35 out of 50 hands. Based upon Lanz classification, frequency of variations in present series was variation in the course of thenar branch (58%), accessory branches at the distal portion of the carpal tunnel (34%), high divisions of the median nerve (8%) and accessory branches proximal to the carpal tunnel (nil). Rare variations including transligamentous median nerve and multiple thenar branches were also observed. Medial take off of thenar branch as observed in this series has special clinical significance in carpal tunnel release. Knowledge of the variable anatomy of median nerve would help to avoid incomplete decompression at operations for nerve entrapment and injury to thenar branch.

P4.5 Variants of local injury of median nerve in carpal tunnel

P4.5 Variants of local injury of median nerve in carpal tunnel

Carpal tunnel syndrome caused by cysticercosis

ABSTRACTWe present a case of carpal tunnel syndrome (CTS) due to compression of the median nerve within the carpal tunnel, caused by cysticercosis. Nerve conduction studies revealed severe CTS. Magnetic resonance imaging suggested an inflammatory mass compressing the median nerve in carpal tunnel. The histological diagnosis was consistent with cysticercosis. The case resolved with conservative treatment. Such solitary presentation of entrapment median neuropathy as CTS caused by cysticercosis is extremely rare. To our knowledge, this is the only case of its kind reported in literature till date.

Carpal tunnel syndrome caused by cysticercosis

We present a case of carpal tunnel syndrome (CTS) due to compression of the median nerve within the carpal tunnel, caused by cysticercosis. Nerve conduction studies revealed severe CTS. Magnetic resonance imaging suggested an inflammatory mass compressing the median nerve in carpal tunnel. The histological diagnosis was consistent with cysticercosis. The case resolved with conservative treatment. Such solitary presentation of entrapment median neuropathy as CTS caused by cysticercosis is extremely rare. To our knowledge, this is the only case of its kind reported in literature till date.

The effect of wrist splint on grasp strength in patients with idiopathic carpal tunnel syndrome

Introduction : carpal tunnel syndrome is one of the most common causes of wrist pain in middle-aged people with consequent problems in wrist movements. This syndrome is more prevalent in women than in men. The carpal tunnel syndrome is caused by blockage of median nerve in carpal tunnel. During moving hands, affected people may feel numbness and tingling which may eliminate by depression from the median nerve. Determine the effect of wrist support splint on grasp strength in patient with idiopathic carpal tunnel syndrome. Method : twenty-eight patients with carpal tunnel syndrome were first evaluated and then randomly assigned to intervention and control groups of 14 subjects each. Subjects in the first group (intervention) were given the wrist splint while those in the second group (control) did not receive any splint. The rate of the disease signs, syndrome intensity and grasp strength were measured and recorded three weeks before starting the study and re-evaluated three week after the completion of the program. The Visual Analogue Scale was applied for measuring pain levels and syndrome intensity was assessed through a questionnaire. Grasp strength was evaluated by a dynamometer. Result s: In intervention group, a significant decrease in the rate of disease signs and in the intensity of syndrome was observed along with a significant increase in grasp strength. Conclusion: According to the study’s results, using a wrist-support splint results in decrement of the diseases signs and syndrome intensity and also in improved grasp strength as well as the efficiency of wrist. Key words: carpal tunnel syndrome, grasp strength, pain, Body Mass Index

3369: High resolution ultrasonography of carpal tunnel syndrome: A dynamic evaluation

Objectives: To assess the median nerve in carpal tunnel with motion of the wrists and hands.Methods: Seventy wrists of 50 patients with proved carpal tunnel syndrome were enrolled (group A). The 30 asymptomatic wrists (group B) and 50 wrists of 25 volunteers (group C) were scanned for comparison. Axial high resolution ultrasonography (HRUS) scanning of wrists through the pre-tunnel, proximal tunnel and distal tunnel with wrists in neutral and extension, and fingers in rest and flexion was performed. The shape, cross-sectional area (CSA) and flattening ratio (FR) of median nerve were assessed. The sliding distance of median nerve with motion of wrists and hands were recorded.Results: With wrists in neutral position and fingers in rest, the mean CSA of the median nerve were significantly enlarged in group A. The mean FR of the median nerve at proximal tunnel level was significantly increased in group A. With wrists in extension position and fingers flexion, the mean distance of median nerve sliding was significantly decreased in group A and group B.Conclusions: The HRUS might be useful for the evaluation of carpal tunnel syndrome. The decrease in mobility of the median nerve in the carpal tunnel might be a predisposing factor of carpal tunnel syndrome. Objectives: To assess the median nerve in carpal tunnel with motion of the wrists and hands. Methods: Seventy wrists of 50 patients with proved carpal tunnel syndrome were enrolled (group A). The 30 asymptomatic wrists (group B) and 50 wrists of 25 volunteers (group C) were scanned for comparison. Axial high resolution ultrasonography (HRUS) scanning of wrists through the pre-tunnel, proximal tunnel and distal tunnel with wrists in neutral and extension, and fingers in rest and flexion was performed. The shape, cross-sectional area (CSA) and flattening ratio (FR) of median nerve were assessed. The sliding distance of median nerve with motion of wrists and hands were recorded. Results: With wrists in neutral position and fingers in rest, the mean CSA of the median nerve were significantly enlarged in group A. The mean FR of the median nerve at proximal tunnel level was significantly increased in group A. With wrists in extension position and fingers flexion, the mean distance of median nerve sliding was significantly decreased in group A and group B. Conclusions: The HRUS might be useful for the evaluation of carpal tunnel syndrome. The decrease in mobility of the median nerve in the carpal tunnel might be a predisposing factor of carpal tunnel syndrome.