Seung Nam Yang | 8 Articles |
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Objective
To evaluate the relationship between the palmar cutaneous branch of median nerve (PCBMN) and surrounding anatomical structures by using high-resolution ultrasound (HRUS) to assess the risk of PCBMN injury. Methods The PCBMN course and the characteristics of bilateral distal forearms and wrists of 30 healthy volunteers were identified. The distance between PCBMN and other anatomical structures at three different levels along its course were measured using HRUS. Moreover, the depth of PCBMN from skin and its cross-sectional area (CSA) were measured. Results HRUS showed the PCBMN in all subjects. PCBMN branched off from the radial aspect of the median nerve (MN) at 4.69±0.89 cm proximal to the bistyloid line (BSL) and extended radially toward the flexor carpi radialis (FCR) tendon. PCBMN was within the ulnar edge of FCR tendon sheath, and became more superficial and perforated the antebrachial fascia between the FCR tendon laterally and the palmaris longus (PL) tendon medially. PCBMN was located at 4.08±0.72 mm on the ulnar aspect of the FCR tendon and 4.78±0.36 mm radially on the PL tendon at BSL. At the distal wrist crease level, the PCBMN was located at 5.68±0.58 mm on the ulnar side of the FCR tendon. The PCBMN depth from skin at BSL and its branching point was 1.92±0.41 and 7.95±0.79 mm, respectively. The PCBMN CSA was 0.26±0.15 mm2 at BSL. Conclusion HRUS can be used to identify PCBMN and its relationship with other anatomical structures. Our data can be used to predict PCBMN location, and prevent complications associated with invasive procedures involving the wrist. Citations Citations to this article as recorded by
To evaluate the risk of phrenic nerve injury during ultrasound-guided stellate ganglion block (US-SGB) according to sonoanatomy of the phrenic nerve, and determine a safer posture for needle insertion by assessing its relationship with surrounding structure according to positional change. Twenty-nine healthy volunteers were recruited and underwent ultrasound in two postures, i.e., supine position with the neck extension and head rotation, and lateral decubitus position. The transducer was placed at the anterior tubercle of the C6 level to identify phrenic nerve. The cross-sectional area (CSA), depth from skin, distance between phrenic nerve and anterior tubercle of C6 transverse process, and the angle formed by anterior tubercle, posterior tubercle and phrenic nerve were measured. The phrenic nerve was clearly identified in the intermuscular fascia layer between the anterior scalene and sternocleidomastoid muscles. The distance between the phrenic nerve and anterior tubercle was 10.33±3.20 mm with the supine position and 9.20±3.31 mm with the lateral decubitus position, respectively. The mean CSA and skin depth of phrenic nerve were not statistically different between the two positions. The angle with the supine position was 48.37°±27.43°, and 58.89°±30.02° with the lateral decubitus position. The difference of angle between the two positions was statistically significant. Ultrasound is a useful tool for assessing the phrenic nerve and its anatomical relation with other cervical structures. In addition, lateral decubitus position seems to be safer by providing wider angle for needle insertion than the supine position in US-SGB. Citations Citations to this article as recorded by
To investigate whether an audible cracking sound during shoulder manipulation following distention arthrography is clinically significant in patients with adhesive capsulitis of the shoulder. A total of 48 patients (31 women, 17 men) with primary adhesive capsulitis of the shoulder completed the study. All participants underwent C-arm-guided arthrographic distention of the glenohumeral joint with injections of a corticosteroid and normal saline. After distention, we performed flexion and abduction manipulation of the shoulder. The patients were grouped into sound and non-sound groups based on the presence or absence, respectively, of an audible cracking sound during manipulation. We assessed shoulder pain and disability based on a Numeric Rating Scale (NRS), the Shoulder Pain and Disability Index (SPADI), and passive range of motion (ROM) measurements (flexion, abduction, internal and external rotation) before the procedure and again at 3 weeks and at 6 weeks after the intervention. The patients were divided into two groups: 21 were included in the sound group and 27 in the non-sound group. In both groups, the results of the NRS, SPADI, and ROM assessments showed statistically significant improvements at both 3 and 6 weeks after the procedure. However, there were no significant differences between the two groups except with respect to external rotation at 6 weeks, at which time the sound group showed a significant improvement in external rotation when compared with the non-sound group (p<0.05). These findings showed that manipulation following distention arthrography was effective in decreasing pain and increasing shoulder range of motion. In addition, the presence of an audible cracking sound during manipulation, especially on external rotation, was associated with better shoulder range of motion. Citations Citations to this article as recorded by
To verify the utility of the lateral femoral cutaneous nerve (LFCN) ultrasound-guided conduction technique compared to that of the conventional nerve conduction technique. Fifty-eight legs of 29 healthy participants (18 males and 11 females; mean age, 42.7±14.9 years) were recruited. The conventional technique was performed bilaterally. The LFCN was localized by ultrasound. Cross-sectional area (CSA) of the LFCN and the distance between the anterior superior iliac spine (ASIS) and the LFCN was measured. The nerve conduction study was repeated with the corrected cathode location. Sensory nerve action potential (SNAP) amplitudes of the LFCN were recorded and compared between the ultrasound-guided and conventional techniques. Mean body mass index of the participants was 23.7±3.5 kg/m2, CSA was 4.2±1.9 mm2, and the distance between the ASIS and LFCN was 5.6±1.7 mm. The mean amplitude values were 6.07±0.52 µV and 6.66±0.54 µV using the conventional and ultrasound-guided techniques, respectively. The SNAP amplitude of the LFCN using the ultrasound-guided technique was significantly larger than that recorded using the conventional technique. Correcting the stimulation position using the ultrasound-guided technique helped obtain increased SNAP amplitude. Citations Citations to this article as recorded by
Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal dominantly inherited disorder that affects peripheral nerves by repeated focal pressure. HNPP can be diagnosed by clinical findings, electrodiagnostic studies, histopathological features, and genetic analysis. Ultrasonography is increasingly used for the diagnosis of neuromuscular diseases; however, sonographic features of HNPP have not been clearly defined. We report the sonographic findings and comparative electrodiagnostic data in a 73-year-old woman with HNPP, confirmed by genetic analysis. The cross-sectional areas of peripheral nerves were enlarged at typical nerve entrapment sites, but enlargement at non-entrapment sites was uncommon. These sonographic features may be helpful for diagnosis of HNPP when electrodiagnostic studies are suspicious of HNPP and/or gene study is not compatible. Citations Citations to this article as recorded by
To investigate the factors which affect the motor evoked potential (MEP) responsiveness and parameters and to find the correlation between the function of the upper extremities and the combined study of MEP with a diffusion tensor tractography (DTT) in patients with stroke. A retrospective study design was used by analyzing medical records and neuroimaging data of 70 stroke patients who underwent a MEP test between June 2011 and March 2013. MEP parameters which were recorded from the abductor pollicis brevis muscle were the resting motor threshold, latency, amplitude, and their ratios. Functional variables, Brunnstrom stage of hand, upper extremity subscore of Fugl-Meyer assessment, Manual Function Test, and the Korean version of Modified Barthel Index (K-MBI) were collected together with the biographical and neurological data. The DTT parameters were fiber number, fractional anisotropy value and their ratios of affected corticospinal tract. The data were compared between two groups, built up according to the presence (MEP-P) or absence (MEP-N) of MEP on the affected hand. Functional and DTT variables were significantly different between MEP-P and MEP-N groups (p<0.001). Among the MEP-P group, the amplitude ratio (unaffected/affected) was significantly correlated with the Brunnstrom stage of hand (r=-0.427, p=0.013), K-MBI (r=-0.380, p=0.029) and the time post-onset (r=-0.401, p=0.021). The functional scores were significantly better when both MEP response and DTT were present and decreased if one or both of the two studies were absent. This study indicates MEP responsiveness and amplitude ratio are significantly associated with the upper extremity function and the activities of daily living performance, and the combined study of MEP and DTT provides useful information. Citations Citations to this article as recorded by
Lofgren's syndrome is an acute form of sarcoidosis characterized by erythema nodosum, bilateral hilar lymphadenopathy (BHL), and polyarthralgia or polyarthritis. This syndrome is common among Caucasians but rare in the Korean population. A 44-year-old woman was admitted to our hospital complaining of polyarthralgia. A chest radiograph revealed BHL and nodular shadows. Angiotensin-converting enzyme levels were within the normal range. Tissue biopsy from a mediastinum lymph node showed noncaseating granulomas. We diagnosed her with Lofgren's syndrome, an acute form of sarcoidosis. Citations Citations to this article as recorded by
True neurogenic thoracic outlet syndrome (TOS) is an uncommon disease and is difficult to diagnose at the early stage and then completely cure. We experienced a case of true neurogenic TOS with typical clinical symptoms and electrophysiologic findings as a result of repetitive habitual sleep posture. A 31-year-old woman who had complained of progressive tingling sensation on the 4th and 5th fingers with shoulder pain was diagnosed of brachial plexopathy at the lower trunk level by electrodiagnostic studies. There was no other cause of brachial plexopathy except her habit of hyperabduction of shoulder during sleep. This case demonstrated that the habitual abnormal posture can be the only major cause of neurogenic TOS. It is of importance to consider TOS with the habitual cause because simple correction of the posture could stabilize or even reverse disease progress. Citations Citations to this article as recorded by
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