Clinical Factors Associated With Balance Function in the Early Subacute Phase After Stroke.

OBJECTIVE: The aim of the study was to investigate the key factors of balance function in the early subacute phase after stroke. DESIGN: Ninety-four stroke patients were included. Multiple variables were evaluated, including demographic factors, clinical variables (stroke type; lesion site; Mini-Mental State Examination; motor strength of the hip, knee, and ankle joints; Fugl-Meyer Assessment of lower extremity), neurophysiological variables (amplitude ratio of somatosensory evoked potential of the tibial nerves), and laterality index of fractional anisotropy of the corticospinal tract using diffusion tensor imaging. Balance function was measured using the Berg Balance Scale. RESULTS: The Berg Balance Scale score was significantly negatively correlated with age and laterality index of fractional anisotropy and positively correlated with Mini-Mental State Examination; Fugl-Meyer Assessment of lower extremity; motor strength of the affected hip, knee, and ankle joint; and somatosensory evoked potential amplitude ratio (P < 0.05). The abnormal somatosensory evoked potential group and poor integrity of the corticospinal tract group showed significantly decreased Berg Balance Scale scores. In multivariable logistic regression analysis, age, Fugl-Meyer Assessment of lower extremity score, and ankle plantar flexion strength were significantly associated with balance function (odds ratios = 0.919, 1.181, and 15.244, respectively, P < 0.05). CONCLUSIONS: Higher age, severe initial motor impairment, and strength of the affected lower limb muscles, especially the ankle plantar flexor, are strongly associated with poor balance function early after stroke. TO CLAIM CME CREDITS: Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME. CME OBJECTIVES: Upon completion of this article, the reader should be able to: (1) Enhance ability to evaluate motor and balance function of stroke patients by learning common assessment tools including clinical tests, neurophysiological and neuroimaging studies; (2) Explain the important factors associated with balance function impairment in early subacute stroke patients; and (3) Enhance planning rehabilitation strategies for improvement of balance function according to recovery stage after stroke. LEVEL: Advanced. ACCREDITATION: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.The Association of Academic Physiatrists designates this Journal-based CME activity for a maximum of 1.0 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

Palmar Digital Neuropathy With Anatomical Variation of Median Nerve: Usefulness of Orthodromic Technique: A Case Report.

Anatomic variation of palmar digital nerve pathways were reported in several cases. Selective exploration of palmar digital nerves with a nerve conduction study has been challenging, because of technical issues. We report a patient who received bilateral carpal tunnel release operation, complaining of a tingling sensation, and hypoesthesia on the middle and ring fingers. An electrodiagnostic study revealed a sensory neuropathy of palmar digital nerve of the left median nerve, supplying the ulnar side of the middle finger, and radial side of the ring finger. She underwent re-operation of open left carpal tunnel release, and a branching site of common digital nerves of the median nerve was identified not at the palm, but at a far proximal site around the distal wrist crease. Usefulness of an orthodromic sensory conduction study was clarified to eliminate volume conducted response or co-activation of nearby nerves in the patient with selective involvement of palmar digital nerve.

Early Detection of Diabetic Polyneuropathy Using Paired Stimulation Studies of the Sensory Nerves.

OBJECTIVE: This study seeks to use the relative refractory period, a sensitive parameter for detecting early change in peripheral polyneuropathies, as a tool for early detection of diabetic polyneuropathy. DESIGN: The relative refractory period of the median and sural sensory nerves was measured in 57 diabetic patients (male 31, female 26) and 23 healthy controls (male 16, female 7). The shortest interstimulus interval, where the latency of the response to the second stimulus recovers to normal, was defined as the relative refractory period. RESULTS: The relative refractory period of the median and sural nerves were significantly longer in diabetic patients (3.6 msec, P < 0.001, and 3.8 msec, P < 0.001, respectively) than in the control group (3.0 msec in both nerves). Relative refractory period values of both nerves were also significantly prolonged compared with the control group, even in diabetic patients without diabetic polyneuropathy based on conventional conduction studies (3.3 msec, P = 0.002, for median nerve; 3.5 msec, P < 0.001, for sural nerve) or without any clinical symptoms and signs (3.3 msec, P = 0.007, for median nerve; 3.5 msec, P = 0.001, for sural nerve). CONCLUSIONS: The relative refractory period was prolonged in diabetic patients even before other electrophysiologic abnormalities or clinical findings appeared. These results suggest that the relative refractory period can be a possible early indicator of diabetic polyneuropathy.

Complex Regional Pain Syndrome of Non-hemiplegic Upper Limb in a Stroke Patient: A Case Report.

Complex regional pain syndrome (CRPS) type I in stroke patients is usually known to affect the hemiplegic upper limb. We report a case of CRPS presented in an ipsilesional arm of a 72-year-old female patient after an ischemic stroke at the left middle cerebral artery territory. Clinical signs such as painful range of motion and hyperalgesia of her left upper extremity, swollen left hand, and dystonic posture were suggestive of CRPS. A three-phase bone scintigraphy showed increased uptake in all phases in the ipsilesional arm. Diffusion tensor tractography showed significantly decreased fiber numbers of the corticospinal tract and the spinothalamic tract in both unaffected and affected hemispheres. Pain and range of motion of the left arm of the patient improved after oral steroids with a starting dose of 50 mg/day.

Sonography of Carpal Tunnel Syndrome According to Pathophysiologic Type: Conduction Block Versus Axonal Degeneration.

OBJECTIVES: The purpose of this study was to investigate sonographic findings according to the pathophysiologic type in patients with carpal tunnel syndrome. METHODS: We retrospectively reviewed the records of 80 patients (148 hands) with carpal tunnel syndrome. Patients were classified into 3 groups according to electrophysiologic findings: (1) conduction block and conduction delay; (2) axonal degeneration; and (3) mixed. We used sonographic evaluations to assess the cross-sectional area at the distal wrist crease and the distal forearm and the wrist-to-forearm ratio of the median nerve. RESULTS: Patients with axonal degeneration had significantly larger cross-sectional areas and wrist-to-forearm ratios than those with a conduction block (P < .05). The increased wrist-to-forearm ratio correlated with a reduced amplitude of the sensory nerve action potential, which reflects the degree of axonal degeneration. CONCLUSIONS: The cross-sectional area and wrist-to-forearm ratio were associated with the pathophysiologic type of carpal tunnel syndrome, with larger nerve swellings seen in patients with axonal degeneration compared with those with demyelinating lesions. In addition to helping in the localization of the nerve lesion, sonography may indicate the type of nerve lesion.

Neural substrates of lower extremity motor, balance, and gait function after supratentorial stroke using voxel-based lesion symptom mapping.

INTRODUCTION: Stroke impairs motor, balance, and gait function and influences activities of daily living. Understanding the relationship between brain lesions and deficits can help clinicians set goals during rehabilitation. We sought to elucidate the neural substrates of lower extremity motor, balance, and ambulation function using voxel-based lesion symptom mapping (VLSM) in supratentorial stroke patients. METHODS: We retrospectively screened patients who met the following criteria: first-ever stroke, supratentorial lesion, and available brain magnetic resonance imaging (MRI) data. MRIs of 133 stroke patients were selected for VLSM analysis. We generated statistical maps of lesions related to lower extremity motor (lower extremity Fugl-Meyer assessment, LEFM), balance (Berg Balance Scale, BBS), and gait (Functional Ambulation Category, FAC) using VLSM. RESULTS: VLSM revealed that lower LEFM scores were associated with damage to the bilateral basal ganglia, insula, internal capsule, and subgyral white matter adjacent to the corona radiata. The lesions were more widely distributed in the left than in the right hemisphere, representing motor and praxis function necessary for performing tasks. However, no associations between lesion maps and balance and gait function were established. CONCLUSION: Motor impairment of the lower extremities was associated with lesions in the basal ganglia, insula, internal capsule, and white matter adjacent to the corona radiata. However, VLSM revealed no specific lesion locations with regard to balance and gait function. This might be because balance and gait are complex skills that require spatial and temporal integration of sensory input and execution of movement patterns. For more accurate prediction, factors other than lesion location need to be investigated.

Reappraisal of Supraorbital Sensory Nerve Conduction Recordings: Orthodromic and Antidromic Techniques.

OBJECTIVE: To establish a supraorbital nerve sensory conduction recording method and assess its usefulness. METHODS: Thirty-one healthy subjects without a history of trauma or neurological disease were recruited. For the orthodromic procedure, the recording electrode was attached immediately superior to the supraorbital notch. The stimulation electrode was placed on points along the hairline which evoked the largest sensory nerve action potentials (SNAPs). The antidromic sensory response was recorded after switching the recording and stimulating electrodes. The measured parameters were onset latency, peak latency, and baseline to peak amplitude of the SNAPs. The electrophysiological parameters of the bilateral supraorbital nerves were compared. We also recruited two patients who had sensory deficits on one side of their foreheads because of laceration injuries. RESULTS: The parameters of orthodromically recorded SNAPs were as follows: onset latency 1.21±0.22 ms (range, 0.9-1.6 ms), peak latency 1.54±0.23 ms (range, 1.2-2.2 ms), and baseline to peak amplitude 4.16±1.92 µV (range, 1.4-10 µV). Those of antidromically recorded SNAPs were onset latency 1.31±0.27 ms (range, 0.8-1.7 ms), peak latency 1.62±0.29 ms (range, 1.3-2.2 ms), and baseline to peak amplitude 4.00±1.89 µV (range, 1.5-9.0 µV). There was no statistical difference in onset latency, peak latency, or baseline to peak amplitude between the responses obtained using the orthodromic and antidromic methods, and the parameters also revealed no statistical difference between the supraorbital nerves on both sides. CONCLUSION: We have successfully recorded supraorbital SNAPs. This conduction technique could be quite useful in evaluating patients with supraorbital nerve lesions.

Relationship of Vascular Factors on Electrophysiologic Severity of Diabetic Neuropathy.

OBJECTIVE: To investigate the impact of vascular factors on the electrophysiologic severity of diabetic neuropathy (DPN). METHODS: Total 530 patients with type 2 diabetes were enrolled retrospectively. We rated severity of DPN from 1 (normal) to 4 (severe) based on electrophysiologic findings. We collected the data concerning vascular factors (including brachial-ankle pulse wave velocity [PWV], ankle brachial index, ultrasound of carotid artery, lipid profile from the blood test, and microalbuminuria [MU] within 24 hours urine), and metabolic factors of diabetes (such as glycated hemoglobin [HbA1c]). We analyzed the differences among the four subgroups using χ(2) test and ANOVA, and ordinal logistic regression analysis was performed to investigate the relationship between significant variables and severity of DPN. RESULTS: The severity of DPN was significantly associated with duration of diabetes, HbA1c, existence of diabetic retinopathy and nephropathy, PWV, presence of plaque, low density lipoprotein-cholesterol and MU (p<0.05). Among these variables, HbA1c and presence of plaque were more significantly related with severity of DPN in logistic regression analysis (p<0.001), and presence of plaque showed the highest odds ratio (OR=2.52). CONCLUSION: Our results suggest that markers for vascular wall properties, such as PWV and presence of plaque, are significantly associated with the severity of DPN. The presence of plaque was more strongly associated with the severity of DPN than other variables.

Efficacy of Optimal Recording Electrode Placement for Median-Lumbrical and Ulnar-Interossei/Lumbrical Distal Latency in the Diagnosis of Carpal Tunnel Syndrome.

PURPOSE: This study is to determine the diagnostic utility of optimal recording electrode placement for distal latency comparison of median-second lumbrical and ulnar-interossei/third lumbrical (M2L-UI3L) in carpal tunnel syndrome. METHODS: Sixty-five hands of control and 75 hands of 62 clinically suspected carpal tunnel syndromes were used for the M2L-UI3L and standard conduction studies. To obtain optimal M2L-UI3L, the recording active electrode (E1) was placed at the midpalm over the third metacarpal bone, whereas the reference electrode (E2) was attached to the palmar digital crease area. Then, median and ulnar nerves were stimulated on the wrist each at 8 cm proximal to E1. M2L-UI3L and standard nerve conduction studies were performed. Sensitivity and specificity of M2L-UI3L were measured in the diagnosis of mild carpal tunnel syndrome. RESULTS: For statistical analysis, the receiver operating characteristics and Student t-test were used. The area under the receiver operating characteristic curve of M2L-UI3L was 0.993. Diagnostic cutoff value of M2L-UI3L greater than 0.6 milliseconds yields sensitivity of 93% and specificity of 97%. The distal median motor latency to the second lumbrical alone showed the area under the curve of 0.998, and the diagnostic cutoff value greater than 3.4 milliseconds yields sensitivity of 96% and specificity of 100%. CONCLUSIONS: This technique for M2L-UI3L shows high sensitivity and specificity compared with the previous reports on the diagnosis of carpal tunnel syndrome. Furthermore, the values of median-second lumbrical motor latency alone have higher sensitivity and specificity, comparable with the median sensory conduction study across the wrist segment.

Correlation between Ultrasonography Findings and Electrodiagnostic Severity in Carpal Tunnel Syndrome: 3D Ultrasonography.

BACKGROUND AND PURPOSE: To determine the correlation between the cross-sectional area (CSA) of the median nerve measured at the wrist using three-dimensional (3D) ultrasonography (US) and the electrophysiological severity of carpal tunnel syndrome (CTS). METHODS: We prospectively examined 102 wrists of 51 patients with clinical CTS, which were classified into 3 groups according to the electrodiagnostic (EDX) findings. Median nerve CSAs were measured using 3D US at the carpal tunnel inlet and at the level of maximal swelling. RESULTS: Ten wrists were negative for CTS. Of the 92 CTS-positive wrists, 23, 30, and 39 were classified as having mild, moderate, and severe CTS, respectively. The median nerve CSA differed significantly between the severe- and moderate-CTS groups (p=0.0007 at the carpal tunnel inlet and p<0.0001 at the maximal swelling site). There was a correlation between median nerve CSA and EDX parameters among those wrists with severe and mild CTS (p<0.0001 at both sites). CONCLUSIONS: The median nerve CSA as measured by 3D US could provide additional information about the severity of CTS, as indicated by the strong correlation with standard EDX findings.

Sonography of the median nerve in carpal tunnel syndrome with diabetic neuropathy.

OBJECTIVE: The aim of this study was to determine the criteria for ultrasonographic measurement of the cross-sectional area (CSA) of the median nerve and differential diagnosis of patients with carpal tunnel syndrome (CTS) with or without diabetic polyneuropathy (DPN). DESIGN: One hundred eighty-seven patients were divided into five groups: healthy controls, CTS, diabetes with CTS but without DPN, DPN only, and both DPN and CTS. The CSAs of the median nerve were measured at four levels, and cutoff values to diagnose CTS with DPN were obtained. RESULTS: All the CSAs were larger in the DPN group compared with those in the control group. The CSAs of the median nerve at the wrist revealed no significant differences among the groups with CTS; however, these groups demonstrated larger CSAs at the wrist and a higher wrist/forearm ratio compared with the DPN only group. The cutoff value for the CSA at the wrist that yielded the highest sensitivity and specificity was 11.6 mm. CONCLUSIONS: The CSA of the median nerve at the wrist and the wrist/forearm ratio could be useful for diagnosing the comorbidity of CTS with DPN.

Ultrasonography of palm to elbow segment of median nerve in different degrees of diabetic polyneuropathy.

OBJECTIVE: To identify the relationship between the ultrasonographic cross-sectional area (CSA) of the median nerve and electrophysiologic findings in diabetic patients. METHODS: Sixty diabetic patients, 30 patients with carpal tunnel syndrome (CTS) and 30 healthy volunteers participated. The participants were divided into 4 groups: Control Group; Group I, diabetic patients without diabetic polyneuropathy (DPN); Group II, diabetic patients with DPN; and Group III, patients with CTS. Group II was subdivided into II-1 and II-2 according to DPN severity. The median nerve CSA was measured at 4 levels, and the wrist-to-forearm ratio (WFR) was calculated. RESULTS: The median nerve CSAs were larger in Group II than in Group I and the Control Group. There were significant differences in the CSA between Group I and Group II-2 and between Group II-1 and II-2. There was no significant difference in the WFR among these groups. The CSAs at the wrist levels and WFR were significantly greater in Group III. CONCLUSIONS: The median nerve CSA was greater in patients with DPN and was related to DPN severity. Diffuse increase in median nerve CSA without change in the WFR might be compatible with DPN. Ultrasonography could be applied for the diagnosis of DPN, especially in advanced cases. SIGNIFICANCE: Ultrasonography might have value in the differential diagnosis of DPN and entrapment neuropathy.

Diagnosis of zygomaticus muscle paralysis using needle electromyography with ultrasonography.

A 22-year-old woman visited our clinic with a history of radiofrequency volumetric reduction for bilateral masseter muscles at a local medical clinic. Six days after the radiofrequency procedure, she noticed a facial asymmetry during smiling. Physical examination revealed immobility of the mouth drawing upward and laterally on the left. Routine nerve conduction studies and needle electromyography (EMG) in facial muscles did not suggest electrodiagnostic abnormalities. We assumed that the cause of facial asymmetry could be due to an injury of zygomaticus muscles, however, since defining the muscles through surface anatomy was difficult and it was not possible to identify the muscles with conventional electromyographic methods. Sono-guided needle EMG for zygomaticus muscle revealed spontaneous activities at rest and small amplitude motor unit potentials with reduced recruitment patterns on volition. Sono-guided needle EMG may be an optimal approach in focal facial nerve branch injury for the specific localization of the injury lesion.

Nerve conduction studies of median motor nerve and median sensory branches according to the severity of carpal tunnel syndrome.

OBJECTIVE: To evaluate each digital branch of the median sensory nerve and motor nerves to abductor pollicis brevis (APB) and 2nd lumbrical (2L) according to the severity of carpal tunnel syndrome (CTS). METHODS: A prospective study was performed in 67 hands of 41 patients with CTS consisting of mild, 23; moderate, 27; and severe cases, 17. Compound muscle action potentials (CMAPs) were obtained from APB and 2L, and median sensory nerve action potentials (SNAPs) were recorded from the thumb to the 4th digit. Parameters analyzed were latency of the median CMAP, latency difference of 2L and first palmar interosseous (PI), as well as latency and baseline to peak amplitude of the median SNAPs. RESULTS: The onset and peak latencies of the median SNAPs revealed significant differences only in the 2nd digit, according to the severity of CTS, and abnormal rates of the latencies were significantly lower in the 2nd digit to a mild degree. The amplitude of SNAP and sensory nerve conduction velocities were more preserved in the 2nd digit in mild CTS and more affected in the 4th digit in severe CTS. CMAPs were not evoked with APB recording in 4 patients with severe CTS, but obtained in all patients with 2L recording. 2L-PI showed statistical significance according to the severity of CTS. CONCLUSION: The branch to the 4th digit was mostly involved and the branch to the 2nd digit and 2L were less affected in the progress of CTS. The second digit recorded SNAPs and 2L recorded CMAPs would be valuable in the evaluation of severe CTS.

Correlation between Location of Brain Lesion and Cognitive Function and Findings of Videofluoroscopic Swallowing Study.

OBJECTIVE: To investigate whether patterns of swallowing difficulties were associated with the location of the brain lesion, cognitive function, and severity of stroke in stroke patients. METHOD: Seventy-six patients with first-time acute stroke were included in the present investigation. Swallowing-related parameters, which were assessed videofluoroscopically, included impairment of lip closure, decreased tongue movement, amount of oral remnant, premature loss of food material, delay in oral transit time, laryngeal elevation, delay in pharyngeal triggering time, presence of penetration or aspiration, and the amount of vallecular and pyriform sinus remnants. The locations of brain lesions were classified into the frontal, parietotemporal, subcortical, medulla, pons, and cerebellum. The degree of cognitive impairment and the severity of stroke were assessed by the Mini Mental Status Examination (MMSE) and the National Institute of Health Stroke Scale (NIHSS), respectively. RESULTS: An insufficient laryngeal elevation, the amount of pyriform sinus, and vallecular space remnant in addition to the incidence of aspiration were correlated with medullary infarction. Other swallowing parameters were not related to lesion topology. Lip closure dysfunction, decreased tongue movement, increased oral remnant and premature loss were associated with low MMSE scores. A delayed oral transit time were associated with NIHSS scores. CONCLUSION: In-coordination of the lip, the tongue, and the oropharynx were associated with the degree of cognitive impairment and the stroke severity rather than with the location of the lesion, whereas incomplete laryngeal elevation and aspiration were predominant in medullary lesions.

Ultrasonography of median nerve and electrophysiologic severity in carpal tunnel syndrome.

OBJECTIVE: To investigate the correlation of the ultrasonographic wrist-to-forearm median nerve area ratio (WFR) and cross sectional area of median nerve at the wrist (CSA-W) to the electrophysiologic severity in patients with carpal tunnel syndrome (CTS). METHOD: One hundred and ten wrists electrophysiologically graded as mild, moderate, and severe CTS and 38 healthy controls underwent ultrasonography of median nerve at the distal wrist crease and mid-forearm. WFR and CSA-W were analyzed according to the severity of CTS. RESULTS: WFR was 1.12±0.14, 1.91±0.33, 2.27±0.47 and 3.02±0.97 and the CSAs-W was 7.23±1.67 mm(2), 13.51±3.72 mm(2), 14.67±2.93 mm(2), and 18.74±6.01 mm(2) in controls, mild (n=28), moderate (n=46), and severe (n=36) CTS, respectively. CSA-W displayed significant differences between the control and the mild CTS, moderate CTS and severe CTS groups. However, there was no significant difference between mild CTS and moderate CTS groups. WFR revealed significant difference between all groups. The sensitivity and specificity of the WFR in grading the severity of CTS were higher than those of the CSA-W. CONCLUSION: Ultrasonography is a useful complementary tool for the evaluation of CTS. Both WFR and CSA-W are highly correlated with severity grade of CTS. However, WFR is superior to CSA-W for diagnosis and grading of the severity of CTS.

Carpal tunnel syndrome and peripheral polyneuropathy in patients with end stage kidney disease.

This study was designed to identify the causes of the development of carpal tunnel syndrome (CTS) associated with end stage kidney disease (ESKD). A total of 112 patients with ESKD, 64 on hemodialysis (HD) and 48 on peritoneal dialysis (PD), were enrolled. The duration of ESKD and dialysis, the site of the arteriovenous (A-V) fistula for HD, laboratory data such as blood urea nitrogen, creatinine, and beta-2-microglobulin were determined. Clinical evaluation of CTS and electrophysiological studies for the diagnosis of CTS and peripheral neuropathy were performed. The electrophysiological studies showed that the frequency of CTS was not different in the HD and PD groups (P = 0.823) and the frequency of CTS was not different in the limb with the A-V fistula compared to the contralateral limb (P = 0.816). The frequency of HD and PD were not related to beta-2-microglobulin levels, an indicator of amyloidosis. The frequency of CTS did not increase as the severity of the peripheral neuropathy and the duration of ESKD and dialysis increased (P = 0.307). The results of this study do not support that microglobulin induced amyloidosis or placement of an A-V fistula are associated with an increase in CTS.

Kinematic analysis of the lumbar spine by digital videofluoroscopy in 18 asymptomatic subjects and 9 patients with herniated nucleus pulposus.

OBJECTIVES: The purpose of this study was to use digital videofluoroscopy to identify motion patterns of the lumbar spine during coronal movement in asymptomatic (normal) subjects and patients with herniated nucleus pulposus (HNP). METHODS: Videofluoroscopic lumbar coronal motion was recorded in 18 asymptomatic volunteers and 9 patients with HNP. Measurements were made while patients bent laterally and rotated toward the right and left from a sitting position and then returned to their original position. Direction and degree of extension in the coronal plane at each motion segment and sacral descent were measured. Through the motion analysis software, the coupled pattern with lateral bending and rotation was analyzed in the asymptomatic subjects and patients with HNP. RESULTS: Lateral flexion movement was coupled with contralateral extension and ipsilateral sacral descent but with a different rotation pattern. Rotation movement was coupled with ipsilateral extension, ipsilateral sacral descent, and ipsilateral spinous process rotation. Patients with HNP and asymptomatic subjects had similar coupled patterns but differences in amount of motion. CONCLUSIONS: Digital videofluoroscopy showed coupled patterns during the lateral bending and rotation movements.

Application of 3-dimensional ultrasonography in assessing carpal tunnel syndrome.

OBJECTIVES: The aim of study was to assess the usefulness of 3D ultrasonography (3DUS) in the diagnosis of carpal tunnel syndrome. METHODS: Fifty patients with carpal tunnel syndrome confirmed by electromyography and 37 healthy control participants underwent 3DUS of the wrists. The mean times per participant for the 3DUS examination and review of the 3D volume set were recorded. The cross-sectional area at the proximal carpal tunnel and the maximum swelling point were measured. Data from patients and controls were compared for determination of statistical significance. The accuracy of the 3DUS diagnostic criteria for carpal tunnel syndrome was evaluated using receiver operating characteristic analysis, and changes in the median nerve shape, including the maximum swelling point, were assessed by review of the 3D volume data. RESULTS: The mean times for examination of a participant and review in each wrist were 56 seconds and 5.7 minutes, respectively. Significant differences were observed in the mean cross-sectional areas of the median nerve between patients and controls. The mean cross-sectional areas ± SD were 16.7 ± 6.7 mm(2) in patients and 8.3 ± 1.9 mm(2) in controls. Using the receiver operating characteristic curve, a cutoff value of greater than 10.5 mm(2) provided diagnostic sensitivity of 84% and specificity of 86%. In 42 of 73 wrists with carpal tunnel syndrome, the median nerve showed fusiform morphologic abnormalities and maximum swelling points. CONCLUSIONS: Our results show that 3DUS could markedly decrease scanning time, and measurement of the median nerve cross-sectional area combined with morphologic analysis using 3DUS is a promising supplementary method for the diagnosis of carpal tunnel syndrome.

Anatomical and electrophysiological myotomes corresponding to the flexor carpi ulnaris muscle.

This study was designed to investigate the incidence of lateral root of the ulnar nerve through cadaveric dissection and to analyze its impact on myotomes corresponding to the flexor carpi ulnaris (FCU) assessed by electrodiagnostic study. Dissection of the brachial plexus (BP) was performed in 38 arms from 19 cadavers, and the connecting branches between the lateral cord and medial cord (or between lateral cord and ulnar nerve) were investigated. We also reviewed electrodiagnostic reports from January 2006 to May 2008 and selected 106 cases of single-level radiculopathy at C6, C7, and C8. The proportion of abnormal needle electromyographic findings in the FCU was analyzed in these patients. In the cadaver study, branches from the lateral cord to the ulnar nerve or to the medial cord were observed in 5 (13.1%) of 38 arms. The incidences of abnormal electromyographic findings in the FCU were 46.2% (36/78) in C7 radiculopathy, 76.5% (13/17) in C8 radiculopathy and 0% (0/11) in C6 radiculopathy. In conclusion, the lateral root of the ulnar nerve is not an uncommon anatomical variation of the BP and the FCU commonly has the C7 myotome. Needle EMG of the FCU may provide more information for the electrodiagnosis of cervical radiculopathy and brachial plexopathy.