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Concept: Median nerve

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BACKGROUND: Variations in the major arteries of the upper limb are estimated to be present in up to one fifth of people, and may have significant clinical implications. CASE PRESENTATION: During routine cadaveric dissection of a 69-year-old fresh female cadaver, a superficial brachioulnar artery with an aberrant path was found bilaterally. The superficial brachioulnar artery originated at midarm level from the brachial artery, pierced the brachial fascia immediately proximal to the elbow, crossed superficial to the muscles that originated from the medial epicondyle, and ran over the pronator teres muscle in a doubling of the antebrachial fascia. It then dipped into the forearm fascia, in the gap between the flexor carpi radialis and the palmaris longus. Subsequently, it ran deep to the palmaris longus muscle belly, and superficially to the flexor digitorum superficialis muscle, reaching the gap between the latter and the flexor carpi ulnaris muscle, where it assumed is usual position lateral to the ulnar nerve. CONCLUSION: As far as the authors could determine, this variant of the superficial brachioulnar artery has only been described twice before in the literature. The existence of such a variant is of particular clinical significance, as these arteries are more susceptible to trauma, and can be easily confused with superficial veins during medical and surgical procedures, potentially leading to iatrogenic distal limb ischemia.

Concepts: Blood pressure, Muscle, Ulna, Forearm, Median nerve, Brachial artery, Muscles of the upper limb, Ulnar artery

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Brachial plexus injuries can permanently impair hand function, yet present surgical reconstruction provides only poor results. Here, we present for the first time bionic reconstruction; a combined technique of selective nerve and muscle transfers, elective amputation, and prosthetic rehabilitation to regain hand function.

Concepts: Surgery, Injury, Amputation, Median nerve, Brachial plexus, Axillary artery, Plexus, Brachial plexus injury

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The boom in computer use and concurrent high rates in musculoskeletal complaints and carpal tunnel syndrome (CTS) among users have led to a controversy about a possible link. Most studies have used cross-sectional designs and shown no association. The present study used longitudinal data from two large complementary cohorts to evaluate a possible relationship between CTS and the performance of computer work.

Concepts: Cross-sectional study, Syndromes, Computer, Computer program, Wrist, Carpal tunnel, Carpal tunnel syndrome, Median nerve

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Purpose: Snapping ulnar nerve syndrome (dislocation of the ulnar nerve over the medial epicondyle) is one of many causes of ulnar neuropathy at the elbow. This preliminary study was performed to search for sonographic signs suggesting the presence of this condition.Methods and Materials: We retrospectively investigated 11 patients with snapping ulnar nerve syndrome (SNAP) in comparison with an age-matched group of 20 patients with idiopathic cubital tunnel syndrome (SNU). Patients were grouped according to the presence of paretic or merely sensory deficits. Nerve cross section area (CSA) and thickness of outer epineurium (ET) was measured and correlated with neurological findings. Statistical differences were evaluated with the Mann-Whitney U-Test.Results: 5 SNAP (10 SNU) patients had sensory symptoms only, 6 SNAP (10 SNU) patients had paretic deficits. CSA in sensory SNU was 0.14 cm2, in paretic SNU 0.19 cm2, in sensory SNAP 0.15 cm2 and in paretic SNAP 0.14 cm2. ET in sensory SNU was 0.85 mm, 0.8 mm in paretic SNU, 1.05 mm in sensory SNAP and 1.1 in paretic SNAP. Differences in CSA were not significant depending on symptoms or group, differences in ET were not significant depending on symptoms but on group (SNAP versus SNU) at α = 0.05.Conclusion: A thickened, hyperechoic outer epineurium in a patient with ulnar neuropathy at the elbow might be a statistically significant differential feature of snapping ulnar nerve syndrome and should be involved in a further functional sonographic evaluation during flexion/extension of the elbow.

Concepts: Statistics, Statistical significance, Humerus, Upper limb anatomy, Ulnar nerve, Median nerve, Cubital tunnel, Ulnar nerve entrapment

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OBJECTIVE: To compare ultrasound measurement of median nerve cross-sectional area (CSA) at different anatomical landmarks and to assess the value of power Doppler signals within the median nerve for diagnosis of carpal tunnel syndrome (CTS). METHODS: A prospective study of 135 consecutive patients with suspected CTS undergoing two visits within 3 months. A final diagnosis of CTS was established by clinical and electrophysiological findings. CSA was sonographically measured at five different levels at forearm and wrist; and CSA wrist to forearm ratios or differences were calculated. Intraneural power Doppler signals were semiquantitatively graded. Diagnostic values of different ultrasound methods were compared by receiver operating characteristic curves using SPSS. RESULTS: CTS was diagnosed in 111 (45.5%) wrists; 84 (34.4%) had no CTS and 49 (20.1%) were possible CTS cases. Diagnostic values were comparable for all sonographic methods to determine median nerve swelling, with area under the curves ranging from 0.75 to 0.85. Thresholds of 9.8 and 13.8 mm(2) for the largest CSA of the median nerve yielded a sensitivity of 92% and a specificity of 92%. A power Doppler score of 2 or greater had a specificity of 90% for the diagnosis of CTS. Sonographic median nerve volumetry revealed a good reliability with an intraclass correlation coefficient of 0.90 (95% CI 0.79 to 0.95). CONCLUSIONS: Sonographic assessment of median nerve swelling and vascularity allows for a reliable diagnosis of CTS. Determination of CSA at its maximal shape offers an easily reproducible tool for CTS classification in daily clinical practice.

Concepts: Diagnosis, Medical ultrasonography, Wrist, Ulnar nerve, Carpal tunnel, Carpal tunnel syndrome, Median nerve, Carpus

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The aim of our study was to describe a dorsal distal radius vascularized bone graft pedicled on the posterior interosseous artery (PIA), and its clinical application in 2 cases of ulnar nonunion. We studied the surgical technique in 5 freshly injected cadavers. The 4th extensor compartment artery originates from the anastomotic arch between the posterior division of the anterior interosseous artery and the PIA and provides periosteal branches to supply the dorsal distal radius metaphysis. A 2-cm vascularized bone graft can be harvested from the radius, and dissection of the PIA enables a long pedicle with a wide arc of rotation able to reach the ulnar diaphysis. The approach is limited to the forearm and distal radius and has minimal donor morbidity.

Concepts: Surgery, Forearm, Median nerve, Pronator quadratus, Arteries of the upper limb, Common interosseous artery, Anterior interosseous artery, Posterior interosseous artery

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The term ‘exploded hand syndrome’ refers to a specific type of crush injury to the hand in which a high compressive force excessively flattens the hand leading to thenar muscle extrusion through burst lacerations. Out of 89 crushed hands seen over a period of seven years, only five had exploded hand syndrome. They were all male industrial workers ranging in age between 24 and 55 years. All patients had thenar muscle extrusion. Other concurrent injuries included fractures/dislocations, compartment syndrome, and ischaemia. All patients were treated by excision of the extruded intrinsic muscles, as well as primary management of concurrent injuries. All patients had functional assessment including: motor power and sensory testing, range of motion of hand joints, and the quick DASH score. Objective testing showed reduced sensibility in the thumb, reduced grip strength (mean 52% of contralateral hand), reduced pinch strength (mean of 27% of contralateral hand), reduced thumb opposition (the mean Kapandji Score was 5 out of 10), and deficits in the range of motion of the metacarpophalangeal and interphalangeal joints of the thumb. The quick DASH score ranged from 11 to 49 and only two patients were able to go back to regular manual work.

Concepts: Injury, Hand, Median nerve, Hand strength, Grip strength, Thumb, Thenar eminence, Work hardening

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BACKGROUND: Contradictory reports have been published regarding the association of Carpal Tunnel Syndrome (C.T.S) and the use of computer keyboard. Previous studies did not take into account the cumulative exposure to keyboard strokes among computer workers. The aim of the present study was to investigate the association between cumulative keyboard use (keyboard strokes) and C.T.S. METHODS: Employees (461) of a Governmental data entry & processing unit accepted to participated in a cross-sectional study (response rate: 84.1%). A questionnaire was distributed to the participants with the aim to obtain information on socio-demographics, and risk factors for CTS. The participants were examined for signs and symptoms related to CTS and were asked about previous history or surgery for CTS. The cumulative amount of the keyboard strokes per worker per year was calculated by the use of payroll’s registry. Two case definitions for CTS were used. The first included subjects with positive personal history of CTS/surgery for CTS while the second included subjects that belonged to the first case definition plus cases identified through clinical examination. RESULTS: Multivariate analysis indicated-for both case definitions- that those employees with high cumulative exposure to keyboard strokes were at increased risk of CTS (case definition A: OR=2.23;95% CI=1.09-4.52 and case definition B: OR=2. 41; 95%CI=1.36-4.25). A dose response pattern between cumulative exposure to keyboard strokes and CTS has been revealed (p<0.001). CONCLUSIONS: The present study indicated a possible association between cumulative exposure to keyboard strokes and the development of CTS. Cumulative exposure to key-board strokes would be taken into account as an exposure indicator regarding exposure assessment of computer workers. Further research is needed in order to test the results of the current study and assess causality between cumulative keyboard strokes and development of CTS.

Concepts: Epidemiology, The Canon of Medicine, Avicenna, Wrist, Carpal tunnel, Carpal tunnel syndrome, Median nerve, Keystroke logging

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OBJECTIVE: This study aims to investigate the involvement of the peripheral nervous system in Ehlers-Danlos syndromes/hypermobility type patients with particular attention to entrapment syndromes. METHODS: We consecutively enrolled Ehlers-Danlos syndromes/hypermobility type patients. Patients underwent clinical, neurophysiological and ultrasound evaluations. Dynamic ultrasound evaluation was also performed in healthy subjects as control group. RESULTS: Fifteen Ehlers-Danlos syndromes/hypermobility type patients and fifteen healthy subjects were enrolled. Most of patients presented tingling, numbness, cramps in their hands or feet. Clinical evaluation was normal in all patients. One patient was affected with carpal tunnel syndrome and one with ulnar nerve entrapment at elbow. One patient had an increased and hypoechoic ulnar nerve at elbow at ultrasound evaluation. Dynamic ultrasound evaluation of ulnar nerve at elbow showed, in patients, twelve subluxations and three luxations. In the control group dynamic evaluation showed one case of ulnar nerve luxation. CONCLUSION: Statistical analysis showed a significant difference in the occurrence of ulnar nerve subluxation and luxation between patients and control subjects. SIGNIFICANCE: The study shows an inconsistency between symptoms and neurophysiological and ultrasound evidences of focal or diffuse nerve involvement. The high prevalence of ulnar nerve subluxation/luxation at elbow in Ehlers-Danlos syndromes/hypermobility type patients could be explained by the presence of Osborne ligament laxity.

Concepts: Nervous system, Syndromes, Paresthesia, Wrist, Carpal tunnel, Carpal tunnel syndrome, Median nerve, Ulnar nerve entrapment

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As carpal tunnel syndrome is more common in women, particularly around the menopause, female-related risk factors are suspected to play a role in its pathogenesis. We have assessed whether female hormone-related symptoms are associated with upper extremity disabilities in women undergoing carpal tunnel release. A total of 92 women with a mean age of 53 years scheduled for surgery for carpal tunnel syndrome were assessed preoperatively for female hormone-related symptoms using the menopausal rating scale and other female-related factors such as menopausal status, pregnancy number and serum female hormone levels. Upper extremity disability was evaluated using the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire. DASH scores had a moderate correlation with total menopausal rating scale scores, but not with other female-related factors assessed. This study suggests that female hormone-related symptoms are associated with subjective upper extremity disabilities in women with carpal tunnel syndrome. This information may be helpful in addressing patients' complex symptoms or interpretation of outcomes in women with carpal tunnel syndrome.

Concepts: Pregnancy, Menopause, Growth hormone, Upper limb, Wrist, Carpal tunnel, Carpal tunnel syndrome, Median nerve