Jianyuan Jiang

Electrophysiological differences between Hirayama disease, amyotrophic lateral sclerosis and cervical spondylotic amyotrophy

BackgroundHirayama disease (HD), amyotrophic lateral sclerosis (ALS) or cervical spondylotic amyotrophy (CSA) may result in atrophy of intrinsic hand and forearm muscles. The incidence of HD is low, and it is rarely encountered in the clinical setting. Consequently, HD is often misdiagnosed as ALS or CSA. It is important to differentiate these diseases because HD is caused by a benign focal lesion that is limited to the upper limbs.MethodsThe thenar and hypothenar compound muscle action potential (CMAP) amplitude of the upper limbs of 100 HD, 97 ALS and 32 CSA cases were reviewed; 35 healthy individuals were included as controls. Seventy-eight percent, 38% and 69% of patients with HD, ALS or CSA had unilateral involvement; the remaining patients were affected bilaterally. Thenar and hypothenar CMAP amplitude evoked by ulnar stimulation was compared with CMAP evoked by median stimulation.ResultsThe ulnar/median CMAP ratio was found to be lower in HD (0.55 ± 0.41, P < 0.0001), higher in ALS (2.28 ± 1.15, P < 0.0001) and no different in CSA (1.21 ± 0.53, P > 0.05) compared with the normal range from previous studies (0.89-1.60) and with the healthy controls (1.15 ± 0.23). Conduction velocities of the sensory and motor nerves, the amplitude of the sensory nerve action potential, and the CMAP amplitude of the unaffected limb were all normal.ConclusionsThe hand muscles were differentially affected between patients with HD, ALS and CSA. The ulnar/median CMAP ratio could be used to distinguish these three diseases.

SIRT1 Plays a Protective Role in Intervertebral Disc Degeneration in a Puncture-induced Rodent Model.

Study Design. Experimental animal study of treatment of intervertebral disc (IVD) degeneration. Objective. This report aims to evaluate the in vivo effects of SIRT1 on IVD biology and to explore its potential mechanism. Summary of Background Data. Silent mating type information regulator 2 homolog 1 (SIRT1) has attracted immense attention because of its functions in a variety of aging-related diseases. Despite previous studies indicated that SIRT1 showed a unique expression with degeneration in some in vitro study, there is no in vivo research on the role SIRT1 plays in IVD and its mechanism. Methods. Coccygeal discs were punctured to induce disc degeneration. Sixteen C57BL/6J mice received either Carboxy methocel (Vehicle) or Resveratrol (RES) gavage. Eight SIRT1+/− mice and their SIRT1+/+ littermates were also used in this study. At 2 and 6 weeks after puncture, magnetic resonance images were obtained. The mice were subsequently killed, and the spine was extracted for further evaluation. Results. Coccygeal disc puncture caused IVD degeneration in the mice. A SIRT1 activator, RES, markedly ameliorated this pathological change, as demonstrated by stronger signal intensity in the T2-weighted images, as well as a significantly lower magnetic resonance imaging grade (at 2 wk vs. Vehicle group P < 0.001). Histological analysis also revealed an improvement in the RES group compared with the Vehicle group (P < 0.05). Genetic ablation of 1 allele significantly enhanced the level of damage relative to the wild-type mice. In addition, SIRT1 activation suppressed the expression of p16 and at the same time, promoted proliferating cell nuclear antigen and type II collagen expression in disc cells, whereas genetic ablation of 1 allele SIRT1 exhibited the opposite consequence. Conclusion. The SIRT1 activator RES protects against puncture-induced disc injury whereas SIRT1 deficiency aggravates tissue injury; the protective role of SIRT1 is partly mediated by suppressing p16, which plays a role in elevating the decreased proliferative ability of the senescent nucleus pulposus cells. Level of Evidence: N/A

Efficacy of anterior cervical decompression and fusion procedures for monomelic amyotrophy treatment: a prospective randomized controlled trial: clinical article.

OBJECT Monomelic amyotrophy (MMA) is a benign, self-limiting lower motor neuron disease. Optimal surgical strategies-discectomy decompression and fusion (DDF) or corpectomy decompression and fusion (CDF)-for patients with aggravated symptoms (within 6 months of presentation) are controversial, particularly in those who are ineligible for conventional treatment. These 2 methods of anterior cervical decompression and fusion for MMA in patients unwilling or unable to wear a conventional cervical collar long term were evaluated. METHODS Anterior cervical decompression and fusion were performed in 48 male patients with MMA between September 2007 and September 2010. Patients were randomly treated with anterior cervical discectomy decompression with autologous iliac crest bone grafting and internal plate fixation (DDF group: 24 patients) or anterior cervical corpectomy, posterior longitudinal ligament resection, autologous iliac crest bone grafting, and internal plate fixation (CDF group: 24 patients). Subjective symptom assessments and electromyography (EMG) examinations were conducted both preoperatively and postoperatively. RESULTS Subjective assessments and EMG studies (mean follow-up duration 25.9 months) indicated improvement in 64.6% and 60% of patients, respectively. No significant correlations between the effectiveness of surgery and age at symptom onset, preoperative symptom duration, or postoperative follow-up time were found. CONCLUSIONS The lack of a significant difference in effectiveness between DDF and CDF favors DDF as more clinically applicable because of its lower procedural risks. As a second-line alternative to cervical collar treatment, surgical anterior cervical decompression and fusion via DDF or CDF may prevent further deterioration and produce good short-term therapeutic effects in patients with MMA; however, cervical collar treatment is recommended for eligible patients because of its lower associated risks.

Lumbar spinal stenosis induced by rare chronic tophaceous gout in a 29-year-old man.

Spinal gout is rare in patients younger than 45 years, occurring most commonly between ages 45 and 80 years. This article describes a 29-year-old man with a history of gout initially observed more than 20 years previously who presented with lower back pain and left lower limb weakness. Computed tomography and magnetic resonance imaging revealed severely damaged facet joints and laminae surrounding L4-S1, and materials with a granular, yellow, cheese-like appearance were observed under direct vision. Postoperative histological examination confirmed spinal gout. Complete posterior decompression was performed concurrently with interbody fusion at L4-L5 and L5-S1. Seventeen-month follow-up revealed good recovery.The mechanism by which urate crystals form preferentially in the spine as opposed to more common soft tissue sites is not well understood. Most reported spinal gout cases were located at L4-S1, which were believed to be the segments with high stresses. These cases occurred in older patients with degenerative spinal diseases and had trauma as indicators. The current authors presume that gout is more likely to exist in the mobile regions with high pressure, such as L4-S1, even in individuals with an initially healthy spine, especially with a long period of abnormal renal dysfunction. Although it is often overlooked in young patients, this condition may be more common than the literature suggests due to the high potential for misdiagnosis in relatively young patients.

A study of dynamic F-waves in juvenile spinal muscular atrophy of the distal upper extremity (Hirayama disease)

OBJECTIVE The study aimed to analyse changes in the upper limb F-waves during neck flexion in patients with Hirayama disease (HD). MATERIAL AND METHODS This study included 41 healthy subjects, 38 HD patients and 24 patients with amyotrophic lateral sclerosis (ALS). Bilateral F-waves were consecutively recorded 20 times with the neck both in the standard position and after persistent neck flexion for 30min. The persistence, minimal latencies, chronodispersion, F/M ratios and amplitudes of the F-waves and repeater F-waves were compared between the standard neck and neck flexion positions. RESULTS During neck flexion, repeater F-waves were found in more HD patients, the percentage of both the ulnar and median repeater F-waves increased significantly, and higher F/M ratios were observed on the symptomatic side (P<0.05). No differences in the F-waves were observed in the healthy subjects or the ALS patients during neck flexion (P>0.05). DISCUSSION HD might be more likely to present as a position-related dysfunction rather than a spinal cord-intrinsic disease. Thus, HD patients could be counselled to avoid neck flexion for long periods of time to prevent further damage, especially in the progressive stage of the disease.

Osteoinductive Activity of ErhBMP-2 After Anterior Cervical Diskectomy and Fusion With a ß-TCP Interbody Cage in a Goat Model

Bone morphogenetic protein (BMP)-2 induces bone and cartilage tissue formation. Large amounts of BMP-2 are difficult to purify or to produce in vitro using eukaryotic cells. The goal of the present study was to assess the clinical use of Escherichia coli-derived recombinant human BMP-2 (ErhBMP-2) on bone fusion after cervical and lumbar spine surgery in a goat model, compared with the standard autogenous iliac bone grafting. Thirty-six goats were randomized to 3 groups: (A) autogenous iliac bone grafting, (B) cervical interbody fusion cage containing ß-tricalcium phosphate (ß-TCP), or (C) cervical interbody fusion cage containing ß-TCP+ErhBMP-2 (2.5 mg). Cervical bone repair was evaluated using radiographs and computed tomography scans at 0, 3, and 6 months. Histological analyses were performed on cervical samples. Two goats died from infection. The differences in intervertebral height among the groups were not significant 3 months postoperatively but became significant after 6 months between groups A vs B and C (P=.04); there was no difference between groups B and C at 6 months. Adding ErhBMP-2 significantly increased cervical fusion at 6 months (P=.04). Histological examinations showed that ß-TCP+ErhBMP-2 increased new bone area, material degradation rate, and depth of tissue penetration and decreased residual material area, all in a time-dependent manner. Escherichia coli-derived rhBMP-2 combined with an enhanced fusion cage containing ß-TCP induced bone formation in a goat model. Furthermore, its ability to promote bone fusion was similar to autogenous iliac bone grafting.

Stab wound with lodged knife tip causing spinal cord and vertebral artery injuries: case report and literature review.

Study Design. Case report and literature review. Objective. To report the case of a young patient who sustained a penetrating wound with a knife tip retained in his cervical vertebrae and to review the literature. Summary of Background Data. Stab wound with foreign body retained, associated with spinal cord injury and vertebral artery injury, is not commonly reported. The timing and approach of surgical intervention are still controversial. Methods. A 17-year-old boy with a wound in the neck presented with diminishing feeling and dysfunction of the left leg and arm. Radiographs demonstrated a foreign body at the C4 level, and possible spinal cord and vertebral artery injuries were detected by computed tomography. Digital subtracted angiography showed a small lateral opening of the injured artery, which was successfully embolized. The knife tip was removed from the original wound without severe cerebrospinal fluid leakage or bleeding, Results. The patient achieved immediate improvement after the operation. Conclusion. Cases of simultaneous spinal cord injury and vertebral artery injury in which the foreign body is retained are uncommonly reported. Digital subtracted angiography is necessary for cervical penetrating wounds and surgical approach should be individualized.

Role of Sirt1 Plays in Nucleus Pulposus Cells and Intervertebral Disc Degeneration.

Study Design. Experimental in vivo and in vitro study of intervertebral disc (IVD) degeneration and the mechanism exploration. Objective. This report aims to verify the expression of Sirt1 in IVD degeneration of different grades and explore its potential mechanism in human nucleus pulposus cells. Summary of Background Data. Silent mating type information regulator 2 homolog 1 (Sirt1) has draw immense attention because of its influence on a variety of aging-related diseases. The present study is a continuation and complement of our former in vivo study of Sirt1 and its role in puncture-induced rodent disc degeneration model. Methods. Sirt1 protein expression level and histological morphology were evaluated in the discs of different degeneration levels, which is graded according to the Pfirrmann grading scale. Then the mRNA and protein expression levels of type II collagen, MMP-13, ADAMTS-5, p21, p16, cell proliferation, and apoptosis ratio were tested in vitro nucleus pulposus cells that expressed different levels of Sirt1 by reverse transcription polymerase chain reaction, western blot analysis, CCK-8 assay, and flow cytometry analysis. Results. Sirt1 protein expression level decreased in the discs of high Pfirrmann grade and the score of histological morphology of human intervertebral disc is consistent with the Pfirrmann grade. Besides, when resveratrol activated Sirt1, nucleus pulposus cells proliferation increased while the cell apoptosis ratio decreased; the expression of type II collagen increased while MMP-13, ADAMTS-5 decreased. It showed the opposite results when the cells were transfected by Sirt1 siRNA. In addition, the expression of both p21 and p16 decreased when Sirt1 was activated. Conclusion. Sirt1 is a protective mediator in IVD degeneration and the expression of Sirt1 decreases in degenerative disc. Activation of Sirt1 works on suppressing cellular senescence, promoting cell proliferation, and restraining the apoptosis of nucleus pulposus cells. Level of Evidence: N/A

Compound Muscle Action Potential Decrement to Repetitive Nerve Stimulation Between Hirayama Disease and Amyotrophic Lateral Sclerosis.

Purpose: To compare repetitive nerve stimulation (RNS) between Hirayama disease (HD) and amyotrophic lateral sclerosis (ALS). Methods: The 3-Hz RNS test was performed on bilateral abductor pollicis brevis, abductor digiti minimi, middle deltoid, and upper trapezius muscles in 33 HD patients and 37 ALS patients. Results: In HD patients, none of tested muscles showed any abnormal decrements (≥10%). Significant decrements were observed in 73% of the ALS patients, and decrements were more frequently observed in proximal muscles (deltoid: 70.3%; trapezius: 48.6%). Illness duration did not correlate with decrement percentage in either patient group, and there was no relationship between decrement incidence and ALS diagnostic category (P > 0.05). Conclusions: The significantly different RNS results between ALS and HD patients support the application of RNS, especially performing RNS in proximal muscles, as a supplementary test in distinguishing these two diseases, even in the early stages. These results may also imply a difference in underlying pathophysiology between ALS and HD.

Diagnostic advantage of S1 foramen-evoked H-reflex for S1 radiculopathy in patients with diabetes mellitus

Hoffmann reflex to tibial nerve stimulation at the popliteal fossa (tibial H-reflex) is routinely used to evaluate S1 radiculopathy. However, it lacks sensitivity because other lesions along this reflex circuit affect the H-reflex bilaterally. This study was undertaken to determine whether the H-reflex evoked by stimulating proximally at the S1 foramen (S1 foramen H-reflex) could improve S1 root lesion evaluation sensitivity in patients with diabetes mellitus. A randomized paired study was designed to evaluate tibial and S1 foramen H-reflexes; bilateral H-M interval (HMI) and H-reflex latency were compared in 22 diabetic patients with unilateral S1 radiculopathy. Other electrophysiological evaluations included standard tibial conduction studies, sural conduction studies and needle electromyography (EMG). The S1 foramen H-reflex had a significantly higher sensitivity (91.0%, 20 of 22) in evaluating S1 radiculopathy than the conventional tibial H-reflex (63.6%, 14 of 22, p < 0.05). Bilateral tibial compound muscle action potential amplitudes were reduced in 3 patients, and sural sensory nerve action potential amplitudes decreased in 7 patients. Needle EMG revealed denervation restricted to the paraspinal muscle and myotomes supplied by the S1 nerve root on the ipsilateral side in 18 patients, and multiple lumbosacral nerve roots were involved bilaterally in the other 4 patients. Our results demonstrate that the S1 foramen H-reflex is a more sensitive assessment of S1 compressive radiculopathy in patients with diabetes mellitus.