BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease involving both upper and lower motor neurons with no effective cure. Electrophysiological studies have found decremental responses during low-frequency repetitive nerve stimulation (RNS) except for diffused neurogenic activities. However, the difference between ALS and generalized myasthenia gravis (GMG) in terms of waveform features is unclear. In the current study, we explored the variation trend of the amplitudes curve between ALS and GMG with low-frequency, positive RNS, and the possible mechanism is discussed preliminarily. METHODS: A total of 85 ALS patients and 41 GMG patients were recruited. All patients were from Peking Union Medical College Hospital (PUMCH) between July 1, 2012 and February 28, 2015. RNS study included ulnar nerve, accessory nerve and facial nerve at 3 Hz and 5 Hz stimulation. The percentage reduction in the amplitude of the fourth or fifth wave from the first wave was calculated and compared with the normal values of our hospital. A 15% decrease in amplitude is defined as a decrease in amplitude. RESULTS: The decremental response at low-frequency RNS showed the abnormal rate of RNS decline was 54.1% (46/85) in the ALS group, and the results of different nerves were 54.1% (46/85) of the accessory nerve, 8.2% (7/85) of the ulnar nerve and 0% (0/85) of the facial nerve stimulation, respectively. In the GMG group, the abnormal rate of RNS decline was 100% (41/41) at low-frequency RNS of accessory nerves. However, there was a significant difference between the 2 groups in the amplitude after the sixth wave. CONCLUSIONS Both groups of patients are able to show a decreasing amplitude of low-frequency stimulation RNS, but the recovery trend after the sixth wave has significant variation. It implies the different pathogenesis of NMJ dysfunction of these 2 diseases.
Action Potentials ; physiology ; Adult ; Aged ; Amyotrophic Lateral Sclerosis ; physiopathology ; therapy ; Electric Stimulation Therapy ; Electromyography ; Female ; Humans ; Male ; Median Nerve ; physiology ; Middle Aged ; Motor Neurons ; physiology ; Muscle, Skeletal ; physiology ; Myasthenia Gravis ; physiopathology ; therapy ; Retrospective Studies ; Ulnar Nerve ; physiology

PURPOSE: Simple decompression of the ulnar nerve has outcomes similar to anterior transposition for cubital tunnel syndrome; however, there is no consensus on the proper technique for patients with an unstable ulnar nerve. We hypothesized that 1) simple decompression or anterior ulnar nerve transposition, depending on nerve stability, would be effective for cubital tunnel syndrome and that 2) there would be determining factors of the clinical outcome at two years. MATERIALS AND METHODS: Forty-one patients with cubital tunnel syndrome underwent simple decompression (n=30) or anterior transposition (n=11) according to an assessment of intra-operative ulnar nerve stability. Clinical outcome was assessed using grip and pinch strength, two-point discrimination, the mean of the disabilities of arm, shoulder, and hand (DASH) survey, and the modified Bishop Scale. RESULTS: Preoperatively, two patients were rated as mild, another 20 as moderate, and the remaining 19 as severe according to the Dellon Scale. At 2 years after operation, mean grip/pinch strength increased significantly from 19.4/3.2 kg to 31.1/4.1 kg, respectively. Two-point discrimination improved from 6.0 mm to 3.2 mm. The DASH score improved from 31.0 to 14.5. All but one patient scored good or excellent according to the modified Bishop Scale. Correlations were found between the DASH score at two years and age, pre-operative grip strength, and two-point discrimination. CONCLUSION: An ulnar nerve stability-based approach to surgery selection for cubital tunnel syndrome was effective based on 2-year follow-up data. Older age, worse preoperative grip strength, and worse two-point discrimination were associated with worse outcomes at 2 years.
Adult ; Cubital Tunnel Syndrome/*diagnosis/physiopathology/*surgery ; Decompression, Surgical/*methods ; Female ; Follow-Up Studies ; Hand/surgery ; Hand Strength ; Humans ; Male ; Middle Aged ; Neurosurgical Procedures/*methods ; Prospective Studies ; Recovery of Function ; Surveys and Questionnaires ; Treatment Outcome ; Ulnar Nerve/physiopathology/*surgery ; Young Adult

BACKGROUNDDysfunctional spinal circuit may play a role in the pathophysiology of amyotrophic lateral sclerosis (ALS). The purpose of this study was to use F waves for assessment of segmental motoneuronal excitability following upper motor neuron (UMN) dysfunctions in ALS.

METHODSWe studied the F waves of 152 ulnar nerves recorded from abductor digiti minimi in 82 patients with ALS. Two groups of hands were defined based on the presence or absence of pyramidal signs in the same upper limb. The group with pyramidal signs in the upper limbs was designated as the P group, and the group without pyramidal signs in the upper limbs was designated as the NP group.

RESULTSThe mean (P < 0.001), median (P < 0.001) and maximum (P = 0.035) F wave amplitudes, mean (P < 0.001), median (P < 0.001) and maximum (P = 0.003) F/M amplitude ratio, index repeating neuron (P < 0.001) and index repeater F waves (P < 0.001) of the P group were significantly increased compared with the NP group. No significant differences were identified for F wave chronodispersion (P = 0.628), mean F wave latency (P = 0.151), minimum F wave latency (P = 0.211), maximum F wave latency (P = 0.199), F wave persistence (P = 0.738), F wave duration (P = 0.152), F wave conduction velocity (P = 0.813) and number of giant F waves (P = 0.072) between the two groups.

CONCLUSIONSIn this study, increased F wave amplitude, F/M amplitude ratio and number of repeater F waves reflected enhanced segmental motoneuronal excitability following UMN dysfunctions in ALS.

Adult ; Aged ; Amyotrophic Lateral Sclerosis ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Motor Neuron Disease ; physiopathology ; Motor Neurons ; physiology ; Neural Conduction ; physiology ; Ulnar Nerve ; physiology

BACKGROUNDTo study lesions' location and prognosis of cubital tunnel syndrome (CubTS) by routine motor nerve conduction studies (MNCSs) and short-segment nerve conduction studies (SSNCSs, inching test).

METHODSThirty healthy subjects were included and 60 ulnar nerves were studied by inching studies for normal values. Sixty-six patients who diagnosed CubTS clinically were performed bilaterally by routine MNCSs and SSNCSs. Follow-up for 1-year, the information of brief complaints, clinical symptoms, and physical examination were collected.

RESULTSSixty-six patients were included, 88 of nerves was abnormal by MNCS, while 105 was abnormal by the inching studies. Medial epicondyle to 2 cm above medial epicondyle is the most common segment to be detected abnormally (59.09%), P < 0.01. Twenty-two patients were followed-up, 17 patients' symptoms were improved. Most of the patients were treated with drugs and modification of bad habits.

CONCLUSIONS(1) SSNCSs can detect lesions of compressive neuropathy in CubTS more precisely than the routine motor conduction studies. (2) SSNCSs can diagnose CubTS more sensitively than routine motor conduction studies. (3) In this study, we found that medial epicondyle to 2 cm above the medial epicondyle is the most vulnerable place that the ulnar nerve compressed. (4) The patients had a better prognosis who were abnormal in motor nerve conduction time only, but not amplitude in compressed lesions than those who were abnormal both in velocity and amplitude. Our study suggests that SSNCSs is a practical method in detecting ulnar nerve compressed neuropathy, and sensitive in diagnosing CubTS. The compound muscle action potentials by SSNCSs may predict prognosis of CubTS.

Adult ; Aged ; Cubital Tunnel Syndrome ; physiopathology ; Electromyography ; Electrophysiology ; Female ; Humans ; Male ; Middle Aged ; Neural Conduction ; physiology ; Ulnar Nerve ; physiology

OBJECTIVETo identify whether there is significant changes between the cervical neutral F-waves and cervical flexion F-waves in the patients with Hirayama disease.

METHODSThis study was performed on 25 normal subjects and 22 male patients with identified Hirayama disease (age: 15 to 44 years; height: 165 to 183 cm; duration: 6 to 240 months) between May 2010 and March 2014. Both cervical flexion F-wave (cervical flexion 45 °, 30 minutes) and conventional F-waves to median nerve stimulation and to ulnar nerve stimulation were performed in all subjects bilaterally.

RESULTSwere analyzed by t-test or Fisher exact probability.

RESULTSIn the normal subjects, all measurements of the bilateral F-waves didn't have any difference between the cervical flexion position and the cervical neutral position. On the cervical neutral position, the persistence (t = 5.209, P = 0.000), average latencies (t = 4.731, P = 0.022) and minimal latencies (t = 23.843, P = 0.006) of ulnar F-wave on the symptomatic heavier side from the patients with identified Hirayama disease were significantly lower or longer than those from the normal subjects, and the repeat F-waves were found in 3 patients (13.6%). On the symptomatic lighter side, the ulnar F-waves only had lower persistence (t = 22.306, P = 0.001) along with 5 repeat F-waves. Only lower persistence were found in the median F-wave on the both side (higher side t = 23.696, P = 0.000; lighter side t = 23.998, P = 0.000), along with 5 (22.7%) repeat F-waves on the symptomatic heavier side and 6 (27.3%) ones on the symptomatic lighter side. After cervical flexion maintaining 30 minutes, the increased maximal amplitudes (t = -2.552, P = 0.019), average amplitudes (t = -3.322, P = 0.003), duration (t = -3.323, P = 0.00), persistence (t = -2.604, P = 0.017) and frequency of repeat F-waves (9/22, 41%) (P = 0.044) were found on the symptomatic heavier side of ulnar F-wave, and 5 of 10 absent ulnar F-wave on the cervical neutral position were also recover. The median F-wave on the symptomatic heavier side mainly had increased maximal amplitude (t = -3.847, P = 0.001), average amplitudes (t = -2.188, P = 0.040) and persistence (t = -2.421, P = 0.025), and 1 of 6 absent median F-wave on the cervical neutral position were also recover after cervical flexion.

CONCLUSIONThe cervical flexion F-waves have significant regular changes compared to the cervical neutral F-waves in patients with Hirayama diseases, especially maximal and average amplitudes of F-waves.

Adolescent ; Adult ; Humans ; Male ; Neck ; Range of Motion, Articular ; Spinal Muscular Atrophies of Childhood ; physiopathology ; Ulnar Nerve ; Young Adult

Total elbow arthroplasty was initially used to manage the rheumatoid arthritis of elbow. With the developement of technology in recent decades, the indication of total elbow arthroplasty include the trauma associated unstable joint, traumatic arthritis and distal humerus fractures in elderly. But the high risk of complications, which includes infection, ulnar nerve deficit and tricep insufficiency, is still an unsolved issue. The most widely used approach nowadays is the Bryan-Morrey approach, while some authors also report triceps on approach recently. This article is an overview in approaches and biomechanical researches of total elbow arthroplasy by reviewing the domestic and overseas involved literatures.
Arthroplasty, Replacement, Elbow ; adverse effects ; methods ; Humans ; Muscles ; physiopathology ; Recovery of Function ; Ulnar Nerve ; injuries

Adult ; Aged ; Elbow ; innervation ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Nerve Compression Syndromes ; physiopathology ; surgery ; Recovery of Function ; Ulnar Nerve ; physiopathology ; surgery

BACKGROUND: The aim of this study was to evaluate the contribution of the proximal nerve stump, in end-to-side nerve repair, to functional recovery, by modifying the classic end-to-side neurorrhaphy and suturing the proximal nerve stump to a donor nerve in a rat model of a severed median nerve. METHODS: Three experimental groups were studied: a modified end-to-side neurorrhaphy with suturing of the proximal nerve stump (double end-to-side neurorrhaphy, Group I), a classic end-to-side neurorrhaphy (Group II) and a control group without neurorrhaphy (Group III). Twenty weeks after surgery, grasping testing, muscle contractility testing, and histological studies were performed. RESULTS: The grasping strength, muscle contraction force and nerve fiber count were significantly higher in group I than in group II, and there was no evidence of nerve recovery in group III. CONCLUSIONS: The contribution from the proximal nerve stump in double end-to-side nerve repair might improve axonal sprouting from the donor nerve and help achieve a better functional recovery in an end-to-side coaptation model.
Anastomosis, Surgical/methods ; Animals ; Axons/pathology ; Forelimb ; Hand Strength ; Male ; Median Nerve/pathology/*surgery ; Muscle Contraction ; Muscle, Skeletal/physiopathology ; Nerve Regeneration ; Nerve Transfer/*methods ; Rats ; Rats, Sprague-Dawley ; Recovery of Function ; Ulnar Nerve/pathology/*surgery

OBJECTIVE: This study aimed to clarify the morphology of the Martin-Gruber anastomosis (MGA) in Chinese. METHODS: One hundred and five Chinese upper limbs (36 males and 20 femalese) were dissected to find the connections between medial nerve and ulnar nerve. The MGA was classified as previously described by Lee. RESULTS: MGA was found in 24 cases (22.9%), in 11 of the 36 male and 5 of the 20 female. There was no obvious difference in the frequency of MGA in both upper limbs. Most MGA ulnar position was located at the medial and distal segment of the forearm. CONCLUSION MGA anatomy could play important role in forensic diagnosis of ulnar nerve injury in Chinese population.
Cadaver ; China/epidemiology* ; Expert Testimony/legislation & jurisprudence* ; Female ; Humans ; Male ; Median Nerve/pathology* ; Muscle, Skeletal/innervation* ; Nervous System Malformations/physiopathology* ; Ulnar Nerve/pathology* ; Upper Extremity/innervation*

OBJECTIVE: To study injuries involving brachial plexus and its branches. METHODS: 66 cases collected from 2003 to 2005 in our department were analyzed statistically. RESULTS: 94% of injuries involved young adult males; 94% were blunt force injuries; 34% involved both nerve and bone mainly involving ulnar nerve and ulnar bone (50%); 40% of the injured nerves received electromyogram and 15 nerves were diagnosed with injuries clinically. CONCLUSION Forensic determination on severity of brachial plexus injuries mainly depends on movement recovery of limb. The best time for forensic appraisal is 20 d post operation+L (length of nerve severed distally)/R (growth rate)+90 d.
Adult ; Brachial Plexus/physiopathology* ; Brachial Plexus Neuropathies/physiopathology* ; Electromyography ; Female ; Forearm Injuries/physiopathology* ; Forensic Medicine ; Humans ; Male ; Median Nerve/injuries* ; Trauma Severity Indices ; Ulnar Nerve/injuries* ; Young Adult