Measurements Of Median Nerve Research Articles

Anatomic Variation of the Hamate Hook as a Potential Risk in Endoscopic Carpal Tunnel Release

The purpose of this study was to investigate the incidence of anomalies in patients who underwent endoscopic carpal tunnel release and their relationship with clinical outcomes. This retrospective study included 65 hands of 57 patients (8 men and 49 women; mean age, 64.9 years) who underwent endoscopic carpal tunnel release for carpal tunnel syndrome at our hospital between March 2016 and April 2022. The patients were diagnosed with carpal tunnel syndrome based on clinical observations and electrophysiological studies. On T2-weighted magnetic resonance axial images, the height of the hook of the hamate was measured from the bottom to the tip of the hook, and the total height of the hamate was measured from the dorsal surface of the hamate to the tip of the hook. A hook-to-height ratio of less than 0.34 was defined as hypoplastic, and its incidence was investigated. In addition, electrodiagnostic testing of sensory and motor nerve conduction of the median nerve and patient-reported outcome measurements, including Quick Disabilities of the Arm, Shoulder and Hand score, Boston carpal tunnel questionnaire, and visual analog scale score, were investigated at 6 months after surgery. Adverse events were collected from patient records. The mean hook-to-height ratio was 0.40. Hypoplasia with a ratio ≤0.34 was observed in seven hands (10.8%), and adverse events were observed only in the two cases that had a hypoplastic hook of the hamate (3.07%). The patient-reported outcome measurements and the result of electrodiagnostic testing at 6 months after surgery did not correlate with the height of the hook of the hamate. The incidence of a hypoplastic hook of the hamate is common in patients with carpal tunnel syndrome, and preoperative evaluation of the morphology of the hooks and indications for endoscopic carpal tunnel release in cases of hypoplastic hooks may help predict adverse events. Therapeutic Ⅳ.

Ultrasonographic measurement of median nerve and wrist skin thickness in patients with carpal tunnel syndrome: relationship with clinical, electrophysiologic and functionality.

The study aimed to investigate the relationship between the proximal and distal cross-sectional area (CSA) of the median nerve and wrist skin thickness measured by ultrasound in patients with carpal tunnel syndrome (CTS), demographics, disease characteristics, electrophysiological measurements, symptom severity, functionality, and symptom severity. 98 patients with electrophysiological diagnoses of CTS in the dominant hand were included in the study. Proximal and distal CSAs of the median nerve and wrist skin thickness were measured ultrasonographically. Demographic and disease characteristics of the patients were recorded. Patients were evaluated with the Historical-Objective scale (Hi- Ob) for clinical staging, the Functional status scale (FSS) for functional status, and the Boston symptom severity scale (BSSS) for symptom severity. Ultrasonographic findings were correlated with demographic and disease characteristics, electrophysiological findings, Hi-Ob scala, Functional status scale (FSS), and Boston symptom severity scale (BSSS). Proximal median nerve CSA median was 11.0 (7.0-14.0) mm2, distal median nerve CSA median was 10.5 (5.0-18.0) mm2, and wrist skin thickness was measured 1.10 (0.6-1.40) mm. Median nerve CSAs were positively correlated with the CTS stage and FSS, negatively correlated with the sensory nerve action potential of the median nerve (SNAP) and the compound muscle action potential of the median nerve (CMAP) ( p<0.05). Wrist skin thickness was positively correlated with disease characteristics, including the presence of paresthesia and loss of dexterity and FSS and BSSS levels. Ultrasonographic measurements in CTS are associated with functionality rather than demographics. Especially the increase in wrist skin thickness leads to an increase in symptom severity.

The Morphometric Measurements of Median and Anterior Interosseous Nerve in Entrapment Syndromes in South Indian Population – An Anatomical Guide

Aim: To study the parameters that can help release the median nerve and its branch, the anterior interosseous nerve from entrapment neuropathies and various other lesions warranting surgical correction and infective and traumatic disorders of adjacent structures of the region. Materials and methods: Sixty four upper limbs belonging to South-Indian population were carefully dissected using the Cunningham’s Manual of Practical Anatomy, the axillary region was exposed, the cords of brachial plexus were traced and median nerve was identified with its relation to axillary artery. The upper limbs used were all disarticulated. The median nerve was further traced and exposed in the arm and forearm. Acromion process and medial epicondyle were considered as prominent bony landmarks for median and anterior interosseous nerves respectively. Measurements were taken using a non-stretchable thread and scale with the arm consistently placed in supine position. Results: The formation of the median nerve by the union of the lateral and medial roots was 11.83±2.36 cm and 11.58±2.057 cm on the right and left sides respectively located distal to the acromion process. The distance between the origin of the anterior interosseous nerve and the medial epicondyle was 8.946±1.084 cm on the right side and 8.875±1.109 cm on the left side. Conclusion: The knowledge of the level of union of two roots of median nerve and the origin of anterior interosseous nerve can be of use to surgeons and anatomists while marking the median nerve on the surface and also releasing the median and anterior interosseous nerves to relieve from various entrapment syndromes. The present study provides data that can facilitate easy identification of the prominent landmarks of the nerve during surgical procedures.

Ultrasonography for carpal tunnel syndrome in pregnancy: a prospective cross-sectional study

Confirmation of carpal tunnel syndrome (CTS) diagnosis with sonographic measurement of the median nerve cross sectional area (MN-CSA) is increasing in popularity. We aimed to analyse the ultrasonography (USG) values of MN-CSA in pregnant women with and without CTS symptoms. MN-CSAs of third trimester pregnant women were measured with USG and they were asked about the presence of CTS symptoms. Symptomatic participants were assigned to the CTS group and remaining participants were assigned to the Control group. The groups were compared according to MN-CSA. Twenty-five participants were grouped in CTS group and the remaining 64 participants were grouped in Control group. The MN-CSA was higher in the CTS group (9.44 ± 2.68) than in the Control group (7.20 ± 1.99), p = .00004. Obstetricians can use USG measurement of MN-CSA to confirm CTS diagnosis and consequently can offer conservative management, which is the widely accepted treatment modality in this cohort. Impact statement What is already known on this subject? CTS is the most common mononeuropathy of pregnancy, with up to 62% prevalence rates. The American Association of Neuromuscular & Electrodiagnostic Medicine practice guideline for the diagnosis of CTS recommends sonographic measurement of median nerve swelling at the carpal tunnel inlet as an accurate diagnostic test (Level A). What do the results of this study add? We found that a simple sonographic measurement of median nerve cross sectional area (MN-CSA) at the wrist appears to be a convenient method to confirm clinical CTS diagnosis in pregnant women. This study offers to use USG to confirm clinical CTS diagnosis in third trimester pregnant women before delivery. What are the implications of these findings for clinical practice and/or further research? This study will help to raise awareness of obstetricians about CTS during pregnancy. USG can be an effective first-line confirmatory test for CTS diagnosis in the pregnant population, but further research is necessary to determine a clear cut-off value for MN-CSA. We advise obstetricians to use sonographic measurement of MN-CSA in pregnant women with typical CTS symptoms, which will increase uniformity for consensus development. Obstetricians can offer advice for conservative management of CTS during pregnancy, which is the widely accepted treatment in this cohort.

Cross-Sectional Area Reference Values of Nerves in the Upper and Lower Extremities using Ultrasonography in the Indian Population.

Background and Purpose:Cross-sectional area (CSA) is the most important parameter to study peripheral nerves by high-resolution ultrasonography. The aim was to acquire normative data of CSA of the main upper and lower limb nerves in the Indian population.Methods:CSA of nerves was determined in 100 healthy volunteers at 11 predetermined sites: median and ulnar at the wrist, mid-forearm, elbow; radial (spiral groove); tibial (popliteal fossa, medial malleolus); common peroneal (CPN, fibular head) and sural (lateral malleolus).Results:The mean age of participants was 40.7 ± 13.0 years (range: 18-79). Fifty were < 40 years of age. The mean height, weight and BMI were 161.5 ± 8.3 centimeters (range: 145—179), 58.6 ± 10.1 kilograms (range: 32-90) and 22.4 ± 3.2 kilogram/square meter (range: 14.03-30.44), respectively. The median and ulnar nerve measurements were non-uniform throughout its course, and the CSA was largest at the elbow and ulnar groove, respectively. With advancing age, there was a significant difference for median and ulnar nerves at the wrist (median P = 0.002, ulnar P = 0.009) and tibial nerve (popliteal fossa, P = 0.045, medial malleolus, P = 0.005), CPN (P = 0.047). Men had greater CSA of upper limb nerves and tibial nerves at popliteal fossa (P < 0.05) as compared to women. A positive correlation was noted with weight.Conclusion:It is apt for every defined population to have its own set of normative data of CSA as it varies with ethnicity, age, and the built of individuals. We provide a valuable set of CSA data for nerves in the Indian population, which can be used for comparison while investigating peripheral nerve disorders.

Assessing the Effects of Scapular Positioning on the Morphology of the Median Nerve During Upper Limb Tension Test 1 (ULTT1)

Research Objectives To determine if there is a significant difference in median nerve morphology of the ULTT1 between resting and two scapular testing positions. Design Cross-sectional study utilizing diagnostic ultrasound to view the median nerve. Diagnostic ultrasound is a non-invasive method of viewing certain anatomical structures, as allowed by the ultrasound frequency. Setting Private University research facility. Participants Thirty healthy males and females between age 18-65 were recruited from a sample of convenience. Exclusion criteria: neck, shoulder, elbow, wrist, or back pain; range of motion deficits that would prevent them from doing the testing positions; or neurological symptoms of the upper quarter. Interventions Subjects were tested using the ULTT1 in both blocked and depressed scapular positions with the height and width of the median nerve measured by diagnostic ultrasound. Main Outcome Measures Investigators used the ultrasound unit calipers to measure the height and width of the median nerve in resting and each scapular position. Results Paired t-tests with a p-value of < 0.05 were utilized to compare median nerve measurements in resting and each scapular position. No significant difference in height or width was found between resting, blocked, or depressed scapular positioning, with p-values >0.05. Conclusions Scapular position did not affect the morphology of the median nerve in this study. Author(s) Disclosures No financial gain from this study. To determine if there is a significant difference in median nerve morphology of the ULTT1 between resting and two scapular testing positions. Cross-sectional study utilizing diagnostic ultrasound to view the median nerve. Diagnostic ultrasound is a non-invasive method of viewing certain anatomical structures, as allowed by the ultrasound frequency. Private University research facility. Thirty healthy males and females between age 18-65 were recruited from a sample of convenience. Exclusion criteria: neck, shoulder, elbow, wrist, or back pain; range of motion deficits that would prevent them from doing the testing positions; or neurological symptoms of the upper quarter. Subjects were tested using the ULTT1 in both blocked and depressed scapular positions with the height and width of the median nerve measured by diagnostic ultrasound. Investigators used the ultrasound unit calipers to measure the height and width of the median nerve in resting and each scapular position. Paired t-tests with a p-value of < 0.05 were utilized to compare median nerve measurements in resting and each scapular position. No significant difference in height or width was found between resting, blocked, or depressed scapular positioning, with p-values >0.05. Scapular position did not affect the morphology of the median nerve in this study.

The correlation between pre-operative ultrasonographic median nerve evaluation and the operative procedure in CTS

BackgroundUltrasonography is a convenient non-invasive diagnostic tool with wide availability and cost effectiveness. Musculoskeletal ultrasonography is a growing field used for diagnosis of many musculoskeletal disorders; carpal tunnel syndrome (CTS) could be one of these disorders. The purpose of this study was to assess the impact of median nerve ultrasonography in carpal tunnel syndrome on surgical management, and its added value in operative techniques selection, and in tailoring the surgical steps. Thirty patients with CTS and thirty normal subjects underwent superficial ultrasonography. The cross-sectional area at different levels and flattening ratios were measured on both groups. The patients who had failed conservative treatment had surgical carpal tunnel release.ResultsThere was significant positive correlation between the need for external neurolysis with increased flattening ratio with cutoff values > 4, and between the need for approach extension with increased cross-sectional area difference between pisiform level and pronator quadratus level with cutoff values of cross-sectional area difference > 7.ConclusionsUltrasonographic measurements of median nerve in CTS could be helpful in selection and modification of operative procedure including the surgical approach and need for neurolysis.

Subclinical peripheral neuropathy in patients with chronic obstructive pulmonary disease without hypoxemia

AIM: The aim of the study was to determine the prevalence of subclinical peripheral neuropathy (PNP) in stable chronic obstructive pulmonary disease (COPD) patients without severe hypoxemia. MATERIALS AND METHODS: Fifty-six (52 men and 4 women) patients with COPD without severe hypoxemia, 25 healthy smokers, and 24 healthy nonsmokers were included in the study. The latency, amplitude, and velocity measurements of right and left median motor nerve, tibial motor nerve, peroneal motor nerve, median sensory nerve, sural sensory nerve, right ulnar motor nerve, and right ulnar sensory nerve were performed. RESULTS: A high proportion of PNP was detected in the COPD group compared to the smoker and nonsmoker control groups (41.1%, 36.0%, and 33.3%, respectively). However, the difference between the groups was not statistically significant (P = 0.784). However, some of the electrophysiological measurements were statistically significantly worse in the COPD group (P 0.05). CONCLUSION: The present study demonstrates that the PNP may be an extrapulmonary manifestation of COPD. The physician should be aware of the possibility of PNP in COPD patients without severe hypoxemia.

Diagnostic potential of ultrasound in carpal tunnel syndrome with different etiologies: correlation of sonographic median nerve measures with electrodiagnostic severity

BackgroundCarpal tunnel syndrome (CTS) is the commonest entrapment neuropathy. The aim of this study was to assess the accuracy and validity of high resolution musculoskeletal ultrasound (US) in the diagnosis of CTS in the Saudi population.MethodsSixty patients were diagnosed clinically to have CTS involving 89 wrists that were confirmed by neurophysiologic studies. Each affected wrist was characterized as idiopathic or associated with either diabetes mellitus or hypothyroidism and were assigned a severity grade based on results of neurophysiologic studies. Seventy-six healthy wrists from fifty age, sex and BMI matched healthy subjects were included in the control group. High resolution ultrasound (US) was performed to assess median nerve cross sectional area distal (CSAd) at the entry to the carpal tunnel and proximally (CSAp) at the level of pronator quadratus muscle with a further calculation of their difference (ΔCSA) and their mean average or CSAd+CSAp/2 (CSApd).ResultsThere was a significant difference between both groups regarding mean ± SD of CSAd, CSAp, ∆CSA, and CSApd (p = 0.0001). A positive significant correlation was also found between the CSAd, ∆ CSA and the CSApd measurements with neurophysiologic severity grade of CTS (P = 0.001). A ∆CSA threshold of 2.5 mm2 showed the highest sensitivity and specificity to diagnose CTS in Saudis.ConclusionHigh resolution ultrasound is a valid and accurate diagnostic modality in carpal tunnel syndrome and correlated to CTS severity. A ∆CSA greater than 2.5 mm2 is considered a valid diagnostic value for CTS in our Saudi population. CTS in our patients with diabetes tend to have greater median nerve US measurement values.

Ultrasonographic imaging of the effects of continuous, pulsed or sham ultrasound treatments on carpal tunnel syndrome: A randomized controlled study.

Clinical and electrophysiological effects of therapeutic ultrasound (US) were researched in many studies on patients with CTS with conflicting results. To assess the effects of continuous and pulsed US treatments by ultrasonographic imaging in addition to clinical and electrophysilogical parameters in patients with carpal tunnel syndrome (CTS). Fifty-four patients with idiopathic CTS were randomly divided into three groups. All patients used night splints for two weeks. In addition to splint therapy, continuous, pulsed or sham US treatments were applied to patients 10min/session, 5sessions/week for two weeks. Clinical situation (pain, hand function, strength), electrophysiological studies (motor distal latency, MDL, sensorial distal latency, SDL), and ultrasonographic area measurements of median nerve were evaluated. All evaluations were applied at pretreatment (baseline), posttreatment (2nd week) and in the 6th week. Whereas significant differences were detected for clinical, functional and ultrasonographic imaging findings in each group in the 2nd week and 6th week compared to baseline (p< 0.0167 for both), no electrophysiological improvements were detected in pulsed-US (p> 0.0167) and only improvement for SDL in sham US group in the 2nd week evaluation (p< 0.0167). According to the results of this study, continuous, pulsed or sham US treatments combined with splinting had similar effects on clinical, electrophysiological and ultrasonographic imaging improvements. Additionally, ultrasonographic imaging may be a preferable objective evaluation tool to prove the early posttreatment clinical improvements when electrophysiological changes could not be detected.

Inter-Rater and Intra-Rater Reliability of Sonographic Median Nerve and Wrist Measurements.

Background:Electrophysiologic studies have been considered the “gold standard” in diagnosing carpal tunnel syndrome (CTS); however, reports of false-negative results, as well as discomfort for the patient during the procedure has paved the use of ultrasound, being a painless and cost-efficient tool, as an alternative means for its diagnosis. Various ultrasound parameters assessing the median nerve and wrist dimensions have been described, but description of landmarks to assess these in a reliable manner has been lacking.Methodology:A systematic search of different databases yielded data regarding ultrasound parameters for CTS diagnosis, the landmarks used, and presence of reliability testing. Based on this, three sonologists discussed the external and sonographic landmarks that will be used in measuring the median nerve measurements, bowing of the flexor retinaculum and the carpal tunnel dimensions. A pilot test with two consecutive healthy participants using the discussed ultrasound parameters was carried out, and results were subjected to inter- and intra-rater reliability testing. Modifications were accordingly made on the acquisition of ultrasound image using external landmarks. The reliability testing proper was done with ten consecutive healthy participants.Results:Based on the systematic review and the pilot study, external landmarks were used to locate the median nerve in the forearm, carpal tunnel inlet and outlet. For the forearm measurement, it was taken 10 cm proximal from the distal palmar crease. The distal palmar crease was the external landmark used for the carpal tunnel inlet, while for the carpal tunnel outlet; it was measured 1 cm distal to the distal palmar crease. Instead of using the inner edge of the hook of hamate and trapezium, the apices of these bones were used as the landmarks in measuring the carpal tunnel outlet dimensions. There was excellent intra-rater reliability (mid-forearm, carpal tunnel inlet and outlet) except for the following: cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet and outlet; and bowing of the flexor retinaculum. All the parameters had an excellent inter-rater reliability measured at the three levels (intraclass correlation [ICC]: Of 0.77–0.99) except for CSA of the median nerve at the levels of the forearm (fair-to-good with ICC of 0.71) and the carpal tunnel inlet (fair-to-good reliability of ICC: 0.43).Conclusion:There was an improved inter- and intra-rater reliability when external landmarks were used instead of sonographic landmarks.

Reliability of measurement of the carpal tunnel and median nerve in asymptomatic subjects with ultrasound

BackgroundMorphology 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. ObjectiveThe 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. DesignA cross-sectional methodological study. MethodsAspects measured were mediolateral and anteroposterior diameters, flattening ratio, circularity, perimeter and cross-section area of the carpal tunnel and median nerve. ResultsIntra-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. ConclusionIn the context of this study, ultrasound was a reliable instrument for measuring carpal tunnel and median nerve dimensions in asymptomatic subjects. Level of evidence1b

Morphologic change of nerve and symptom relief are similar after mini-incision and endoscopic carpal tunnel release: a randomized trial

BackgroundThe symptoms in carpal tunnel syndrome (CTS) can be ameliorated by open and endoscopic release of the transverse carpal ligament. It is unknown whether a mini-incision or endoscopic carpal tunnel release more effectively reverses the pathological changes that are observed in the median nerve in patients with CTS and these morphologic changes correlates with the subjective outcomes after carpal tunnel release. We hypothesized that (1) at 24 weeks after surgery, the subjective outcomes of mini-incision release and endoscopic release would not differ in patients with CTS; and (2) the ultrasonographic (US) morphology of the median nerve reverses similarly after mini-incision and endoscopic release; (3) the subjective outcomes correlates with these morphologic changes.MethodsBetween November 2011 and January 2013, 67 patients with CTS in their dominant wrist were randomized to either mini-incision (n = 32) or endoscopic (n = 35) release. Each patient was assessed by both the Boston Carpal Tunnel Questionnaire (BCTQ) and the Disabilities of the Arm, Shoulder, and Hand (DASH) pre-operatively and 24 weeks’ post-operation. An US examination was conducted at both time points to measure the cross-sectional area (CSA) at the inlet, middle, and outlet (CSA-I, CSA-M and CSA-O) and the flattening ratio (FR) at the middle and outlet (FR-M and FR-O) of the median nerve.ResultsThe post-operative mean BCTQ and DASH scores were improved significantly from the pre-operative scores in both groups (p < 0.001). The mean CSA-I decreased and CSA-M and CSA-O increased similarly in both groups (by 3.3, 3.0, and 3.8 mm2 in the mini-incision group and 2.9, 3.1. and 2.7 mm2 in the endoscopic group. The mean FR-M/FR-O decreased similarly from 3.6/4.2 to 3.2/3.0 in the mini-incision group and 3.8/4.3 to 3.2/2.9 in the endoscopic group. There were no significant differences in the subjective outcome scores or median nerve measures between the two groups. Improvement in the BCTQ-S only was significantly correlated with changes in the CSA at the inlet.ConclusionsMini-incision and endoscopic release both similarly relieved subjective symptoms and functions along with the pathological changes in the median nerve morphology along the carpal tunnel in patients with idiopathic CTS. Symptom relief after surgical decompression seems to correlate with reduced nerve swelling at carpal inlet and reversed nerve flattening inside carpal tunnel.Trial registrationThis study was retrospectively registered in “ClinicalTrials.gov” at Oct 18th, 2013, and the registration number was NCT01972165.

Determination of Electrophysiologically Moderate and Severe Carpal Tunnel Syndrome: Ultrasonographic Measurement of Median Nerve at the Wrist

ObjectiveTo establish the cutoff value of cross-sectional area (CSA) of the median nerve at the wrist, for determination of electrophysiologically moderate and severe carpal tunnel syndrome (CTS).MethodsThe prospective study was conducted among patients suspected of having CTS. A total of 106 patients (185 symptomatic wrists) received nerve conduction study (NCS) and ultrasonography. To establish a cutoff value, various diagnostic properties were calculated across a range of the CSA.ResultsA mean±standard deviation of CSA of the median nerve of normal and mild, moderate and severe CTS was 9.4±2.1, 12.0±2.7, 13.8±4.7, and 15.4±4.1 mm2, respectively. The positive relationship between CTS severities and CSA was observed (rs=0.56). A 14 mm2 CSA had sufficient power to rule in moderate and severe CTS, with a specificity of 91.4% and sensitivity of 42.3%. In addition, it showed a post-test probability (positive predictive value) of 86.3% as against a pre-test probability of 56.2%.ConclusionPatients who had ≥14 mm2 of median nerve CSA had very high probability of moderate to severe CTS.

Effects of grip force on median nerve deformation at different wrist angles.

The present study investigated the effects of grip on changes in the median nerve cross-sectional area (MNCSA) and median nerve diameter in the radial-ulnar direction (D1) and dorsal-palmar direction (D2) at three wrist angles. Twenty-nine healthy participants (19 men [mean age, 24.2 ± 1.6 years]; 10 women [mean age, 24.0 ± 1.6 years]) were recruited. The median nerve was examined at the proximal carpal tunnel region in three grip conditions, namely finger relaxation, unclenched fist, and clenched fist. Ultrasound examinations were performed in the neutral wrist position (0°), at 30°wrist flexion, and at 30°wrist extension for both wrists. The grip condition and wrist angle showed significant main effects (p < 0.01) on the changes in the MNCSA, D1, and D2. Furthermore, significant interactions (p < 0.01) were found between the grip condition and wrist angle for the MNCSA, D1, and D2. In the neutral wrist position (0°), significant reductions in the MNCSA, D1, and D2 were observed when finger relaxation changed to unclenched fist and clenched fist conditions. Clenched fist condition caused the highest deformations in the median nerve measurements (MNCSA, approximately −25%; D1, −13%; D2, −12%). The MNCSA was significantly lower at 30°wrist flexion and 30°wrist extension than in the neutral wrist position (0°) at unclenched fist and clenched fist conditions. Notably, clenched fist condition at 30°wrist flexion showed the highest reduction of the MNCSA (−29%). In addition, 30°wrist flexion resulted in a lower D1 at clenched fist condition. In contrast, 30°wrist extension resulted in a lower D2 at both unclenched fist and clenched fist conditions. Our results suggest that unclenched fist and clenched fist conditions cause reductions in the MNCSA, D1, and D2. More importantly, unclenched fist and clenched fist conditions at 30°wrist flexion and 30°wrist extension can lead to further deformation of the median nerve.

Ultrasonographic Assessment of Soft Tissues in Patients With Acromegaly

Objectives: This study aims to investigate ultrasound examination findings of cartilage, tendon and nerve structures in patients with acromegaly and assess whether imaging findings have any association with the clinical and laboratory features of the patients. Patients and methods: The study included 38 diagnosed acromegaly patients (18 males, 20 females; mean age 45.6±10.4 years; range 28 to 63 years) and 21 control subjects (8 males, 13 females; mean age; 43.1±7.4 years; range 29 to 58 years) similar for age, sex and body mass index. Patients’ clinical characteristics and laboratory parameters were recorded. The cross sectional area of median nerve, flexor pollicis longus and Achilles tendon, and humeral cartilage thickness were bilaterally assessed by ultrasound. Results: Arthralgia was present in 13 patients (34.9%) and 11 (28.9%) had paresthesia in the hands. Thickness of humeral cartilage and the cross sectional area of median nerve, flexor pollicis longus tendon and Achilles tendon was significantly higher in acromegaly patients compared with controls (p<0.001). While measurements performed with ultrasound were correlated among themselves, no significant correlation was present between ultrasound measurements and growth hormone and insulin-like growth factor-1. When acromegaly patients were analyzed as active (n=22) and inactive (n=16), no significant difference was determined in the parameters with the exception of median nerve measurements. Conclusion: Ultrasound examination revealed significantly different cartilage, tendon and nerve parameters in acromegaly patients compared to the control group. Median nerve cross sectional area was significantly greater in active patients compared to inactive patients.

THU0358 Gray Scale and Power Doppler Ultrasound Assessment of the Median Nerve: A Biomarker That Can Help in Setting A Treat to Target Approach Tailored for Carpal Tunnel Syndrome Patients

BackgroundThough there are various carpal tunnel syndrome (CTS) treatment options, their outcomes and long-term effects are still debatable. An accurate understanding of the predictive factors of CTS management outcomes would...

Screening for Carpal Tunnel Syndrome Using Sonography

The use of sonography in musculoskeletal research and clinical applications is increasing; however, measurement techniques for diagnosing carpal tunnel syndrome with sonography continue to be inconsistent. Novel methods of measurement using internal comparisons to identify swelling of the median nerve require investigation and comparison to currently used techniques. The flattening ratio of the median nerve, bowing of the flexor retinaculum, and cross-sectional area of the median nerve were collected in the forearm, at the radiocarpal joint, and at the level of the pisiform in both symptomatic patients and asymptomatic control participants. Electrodiagnostic testing was completed in symptomatic patients as a diagnostic standard. Median nerve measurements were collected from 166 wrists of symptomatic and asymptomatic participants. The flattening ratio did not show any correlation to electrodiagnostic testing and was identical between both symptomatic and asymptomatic participants. Moderate to strong correlations were noted between electrodiagnostic testing results and sonographic measurements of the cross-sectional area at the pisiform, retinacular bowing, and both the ratio and change of the cross-sectional area between the forearm and pisiform. The area under the curve was large for all receiver operating characteristic curves for each measurement (0.759-0.899), and sensitivity was high (80.4%-82.4%). Measurement of swelling through a ratio or absolute change had similar diagnostic accuracy as individual measurement of the cross-sectional area within the carpal tunnel. These measures may be useful for improving accuracy in more diverse clinical populations. Further refinement of protocols to identify the largest cross-sectional area within the carpal tunnel region and statistical methods to analyze clustered, multilevel outcome data are recommended to improve diagnostics.

Precision of Novice Sonographers Concerning Median Nerve and Achilles Tendon Measurements

The aim of this study was to quantify how precise the measurements of beginner sonographers (relative to an expert) are concerning small and large ellipsoid structures (median nerve and Achilles tendon). During a 4-day musculoskeletal ultrasonography course at a secondary-care center, 19 attendants and an expert physiatrist sonographer were enrolled. After the hand practice session, the physicians performed median nerve measurements (short axis, long axis, and cross-sectional area) at the level of carpal tunnel on the same subject. Repeat measurements were done at the end of the following day. Similarly, achilles tendon measurements were taken during 2 consecutive days (after the ankle-foot session). An expert sonographer also performed the same evaluations twice, together with the attendants. The mean values of the expert's measurements were used as the "test value" for each parameter. Median nerve long-axis values pertaining to the first trial were found to be smaller than that of the test value (P = 0.003), but those of the second trial were similar to the test value (P = 0.107). Median nerve short-axis and area measurements were not different from the test value in either trials (P > 0.05). Achilles tendon measurements were significantly larger than the test value (P < 0.05) at the first trial but were similar to the test value at the second trial (P > 0.05). Percentage deviations of the attendants' measurements (median nerve short and long axes) were negatively correlated with their sonography experience. We imply that novice sonographers tend to measure small structures smaller and large structures larger. Personal experience seems to play a role especially for small structures, and practice affects the precision of these measurements favorably.

The Effect of Symptoms of Carpal Tunnel Syndrome on Ultrasonographic Median Nerve Measures Before and After Wheelchair Propulsion

To quantify median nerve characteristics before and after strenuous wheelchair propulsion and relate them to symptoms of carpal tunnel syndrome (CTS). We hypothesized that persons with and without symptoms of CTS would have significantly different nerve characteristics at baseline and after propulsion. A repeated-measures design was used to obtain ultrasound images of the median nerve at 3 levels of the wrist (radius, pisiform, and hamate) before and after wheelchair propulsion. Investigators were blinded to subject history related to CTS. The 2007 and 2008 National Veterans Wheelchair Games and the Human Engineering Research Laboratories. Fifty-four participants between the ages of 18 and 65 years with a nonprogressive disability who used a manual wheelchair as their primary means of mobility completed this study. Participants completed questionnaires regarding demographics and the presence and severity of symptoms of CTS. Ultrasound images of the median nerve were obtained before and after a 15-minute strenuous wheelchair-propulsion task. Baseline values and post-propulsion changes were determined for median nerve cross-sectional area, flattening ratio, and swelling ratio. Differences in median nerve variables between symptomatic and asymptomatic groups were assessed. No significant differences between symptom groups were identified at baseline; however, persons with symptoms of CTS showed a significantly different percent change from baseline compared with the asymptomatic participants for cross-sectional area at pisiform (P = .014) and flattening ratio at hamate (P = .022), and they showed a strong trend toward a difference in swelling ratio (P = .0502). For each of these variables, the change in the symptomatic group was in the opposite direction of the change in the asymptomatic group. We found several median nerve responses to wheelchair propulsion associated with symptoms of CTS. These responses occurred even though no baseline ultrasound difference was found based on symptoms. Future research is necessary to determine how propulsion characteristics (ie, force, repetition, and posture) affect the median nerve response.