Evaluation of characteristics and surgical outcomes in cervical spondylotic amyotrophy

Background:

Cervical spondylotic amyotrophy (CSA) is a rare clinical syndrome resulting from cervical spondylosis. Surgical treatment includes anterior cervical decompression and fusion (ACDF), and laminoplasty with or without foraminotomy. Some studies indicate that ACDF is an effective method for treating CSA because anterior decompression with or without medial foraminotomy can completely eliminate anterior and/or anterolateral lesions. We retrospectively evaluated outcome of surgical outcome by anterior cervical decompression and fusion (ACDF).

Materials and Methods:

28 CSA patients, among whom 12 had proximal type CSA and 16 had distal type CSA, treated by ACDF, were evaluated clinicoradiologically. The improvement in atrophic muscle power was assessed by manual muscle testing (MMT) and the recovery rate of the patients was determined on the basis of the Japanese Orthopedic Association (JOA) scores. Patient satisfaction was also examined.

Results:

The percentage of patients, who gained 1 or more grades of muscle power improvement, as determined by MMT, was 91.7% for those with proximal type CSA and 37.5% for those with distal type CSA (P < 0.01). The JOA score-based recovery rates of patients with proximal type and distal type CSA were 60.8% and 41.8%, respectively (P < 0.05). Patient satisfaction was 8.2 for those with proximal type CSA and 6.9 for those with distal type CSA (P < 0.01). A correlation was observed among the levels of improvement in muscle power, JOA score based recovery rate, patient satisfaction and course of disease (P < 0.05).

Conclusion:

ACDF can effectively improve the clinical function of patients with CSA and result in good patient satisfaction despite the surgical outcomes for distal type CSA being inferior to those for proximal type CSA. Course of disease is the fundamental factor that affects the surgical outcomes for CSA. We recommend that patients with CSA undergo surgical intervention as early as possible.     

失神经支配骨骼肌的实验观察

目的切断新西兰大白兔腓肠肌神经后,观察肌内神经、肌梭、运动终板带、肌湿重等的变化,探讨其规律。方法将25只新西兰大白兔随机分成对照组（5只）和神经切断组（20只）。术后2,4,8,12,16周,称肌湿重后用S ihler’s肌内神经染色法染色肌内神经;用乙酰胆碱脂酶整肌染色法染肌运动终板;用HE染色法染肌梭。结果①失神经2周肌湿重为正常的65%,两组比较P〈0.05,肌内神经染色变浅,运动终板带及断面切片上显示数目正常,肌梭形态及梭内肌纤维无改变;②4周肌湿重为正常的53.2%,运动终板带变模糊,数目与正常比较无差别,肌内神经三级分支消失,肌梭数量正常,部分肌梭出现变形;③8周肌肉大量纤维化,湿重为正常的43.97%,运动终板带不连续,数目减少为正常76.2%,两组比较P〈0.05,肌内神经二、三级均无染色,仅留有鞘管样结构,肌梭大部分变形,数量为正常的81%,与正常组比较P〈0.05;④12周肌湿重为正常的42%,与8周相比P〉0.05,运动终板更加分散,形态不规则,数目为正常的54.4%,肌内仅一级神经有部分淡染,肌梭仅为正常的50%。⑤16周肌湿重为正常的41.6%,与12周相比P〉0.05,运动终板无聚合态,一级神经淡染存在,肌梭为正常的48.6%,与12周相比P〉0.05。结论新西兰大白兔腓肠肌失神经支配后,肌湿重、肌内神经、运动终板、肌梭变化有一定规律性,肌萎缩发生最早。     

A case of myasthenia gravis with neurogenic amyotrophy

Summary A 60-year-old woman affected by myasthenia gravis with onset at 27 years is described. At the age of 54 years the patient showed amyotrophy of the shoulders and of the legs with bilateral steppage. There was a gradual worsening and progression of the atrophy to other muscles. The nature of the disease is discussed following EMG and histologic data.

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Zusammenfassung Es wird eine 60jährige Frau, die an Myasthenia gravis leidet, beschrieben. Die Krankheit begann, als sie 27 Jahre alt war. Mit 54 Jahren zeigte die Patientin eine Myatrophie der Schulter und der Beine mit bilateralem Steppengang. Zunehmende Verschlechterung und Übergreifen der Atrophie auf andere Muskelgebiete. Die Natur der Krankheit wird auf der Basis der EMG und der histologischen Befunde besprochen.

     

Amyotrophic cerebellar hypoplasia

Summary Lower motor neuron degeneration, cerebellar hypoplasia, atrophy of pons, olives, and cerebellum, sclerosis of thalamus and pallidum, and deficient myelination were found in a 2-months-old baby with laryngeal paralysis, mental retardation, progressive amyotrophy, and slow nerve conduction velocity. Such changes seem characteristic of an unusual syndrome previously referred to as cerebellar hypoplasia in Werdnig-Hoffmann disease, or anterior horn cell disease with pontocerebellar hypoplasia. Although the pathologic changes in lower motor neurons are indistinguishable from those in other cases of infantile spinal muscular atrophy, the consistent reproducibility of a complex pathologic pattern suggests that this is probably a manifestation of a separate disease process. The term amyotrophic cerebellar hypoplasia (ACH) is a convenient designation for the syndrome.Supported in part by National Institutes of Health grant no. RR75     

Neurological phenotypes in spinocerebellar ataxia type 2: Role of mitochondrial polymorphism A10398G and other risk factors

BackgroundSpinocerebellar ataxia type 2 (SCA2) is due to a CAG expansion (CAGexp) at ATXN2. SCA2 presents great clinical variability, alongside characteristic ataxia with saccadic slowness.AimsTo study parkinsonism, dementia, dystonia, and amyotrophy as subphenotypes of SCA2, and to explore the effect of CAG repeats at different loci and of mitochondrial polymorphism A10398G as modifiers of phenotype.MethodsSymptomatic subjects were classified by presence/absence of neurological signs mentioned above; SARA and NESSCA scores were obtained. CAG repeats at ATXN1, ATXN2, ATXN3, CACNA1A, ATXN7 and RAI1, and polymorphism A10398G at mtDNA were established. Group characteristics were compared, with a p < 0.05.ResultsForty-eight SCA2 individuals were included. Age at onset, CAGexp, and disease duration explained 53% and 43% of SARA and NESSCA variations, respectively. CAGexp of subjects with and without parkinsonism were different (medians of 42 and 39 repeats) as well as of subjects with and without dystonia (44 and 40 repeats). Amyotrophy was not significantly related to any variable under study. Concerning polymorphism A10398G, 83% of subjects with and 34% of those without cognitive decline carried 10398G at (p = 0.003).DiscussionTreating the four phenotypic subgroups as outcomes was a valid strategy to identify modifiers of disease. Among correlations found, some confirmed previous reports, such as that between dystonia and CAGexp. Of note was the association between cognitive decline and the variant G at mitochondrial polymorphism A10398G, a variant formerly related to earlier ages at onset in SCA2.     

Hirayama disease in unilateral and bilateral forms-3 case reports

Hirayama disease is a benign, nonprogressive motor neuron disease affecting the upper limbs. It is secondary to an abnormal anterior displacement of the posterior dura with secondary compression of the lower cervical spinal cord. It should be suspected in young male patients with a chronic history of weakness and atrophy involving the upper extremities followed by clinical stability in few years. The involvement is usually unilateral but may be bilateral. MR imaging is the best way to make the diagnosis but it necessitates the use of both extension/flexion and post contrast studies.     

Pathophysiology and treatment for cervical flexion myelopathy

Previous studies have suggested that spinal cord compression by the vertebral bodies and intervertebral discs during neck flexion cause cervical flexion myelopathy (CFM). However, the exact pathophysiology of CFM is still unknown, and surgical treatment for CFM remains controversial. We examined retrospectively patients with CFM based on studies of the clinical features, neuroradiological findings, and neurophysiological assessments. The objectives of this paper are to investigate the pathophysiology of CFM, and to examine an optimal surgical treatment. Twenty-three patients (20 male, three female) with age of onset ranging from 11 to 23 years (mean 15.7 years) were examined for the study. All patients were inspected by magnetic resonance imaging (MRI), myelogram, or computed tomographic myelogram (CTM) of the cervical spine. In eight patients, dynamic motor evoked potentials (MEP) studies were performed. Five patients underwent surgical treatment; two patients had cervical duraplasty with laminoplasty, two patients had musculotendinous transfer, one patient had both of these procedures, and the remaining 18 patients were treated conservatively. Amyotrophy of the hand intrinsic and flexor muscle group of the forearm except the brachioradial muscle was observed hemilaterally in 20 patients and bilaterally in three patients. In three patients, T1-weighted MRI with neck flexion showed linear high intensity regions in the epidural space. In all patients, axial MRI/CTM demonstrated flattening of the spinal cord with the posterior surface of the dura mater shifting anteriorly. The amplitude of MEPs decreased after cervical flexion in two patients with progressive muscular atrophy. In three patients, dysesthesia of the upper extremities disappeared following cervical duraplasty. Musculotendinous transfer for three patients significantly improved the performance of their upper extremity. The findings of this study suggest that degenerative changes of the dura mater may be a characteristic pathology of CFM. Cervical duraplasty with laminoplasty is effective for cases at an early stage, and musculotendinous transfer should be selected in patients at a late stage.     

近端肌萎缩型颈椎病11例的诊治分析

目的:探讨近端肌萎缩型颈椎病的临床特点、治疗方法及临床效果。方法:回顾性分析2016年9月至2020年12月治疗的11例近端肌萎缩型颈椎病患者,其中男7例,女4例,年龄38~68岁。分析其临床症状特点、MRI及神经电生理表现,分别采用保守治疗或颈椎前路减压融合手术进行治疗,治疗前后采用徒手肌力评定方法(manual muscle test,MMT)对患者进行疗效评价,同时随访患者满意度。结果:所有患者获得随访,时间6~19个月。11例均为单侧发病,主要表现以三角肌、冈上肌、冈下肌萎缩为主,早期可以伴有同侧颈肩痛;MRI显示以C_4,5、C_5,6节段病变多见,神经电生理检查表现为受累肌肉失神经支配,患侧支配神经复合肌肉动作电位(compound muscle action potential,CMAP)波幅较健侧降低。所有手术患者获得骨性融合,1例行颈椎体次切减压融合术(anterior cervical corpectomy and fusion,ACCF)术后出现对侧C₅神经根麻痹,经对症治疗10周后完全恢复。治疗后12个月时根据MMT疗效评估:保守治疗3例,优2例,良1例;手术治疗8例,优3例,良4例,可1例。结论:近端肌萎缩型颈椎病发病率低,表现为单侧近端肌肉萎缩,早期可以伴有同侧颈肩痛,结合MRI、神经电生理检查可以减少误诊。在发病早期尤其是髓核脱出导致神经压迫的可以采取保守治疗,当保守治疗无效或疼痛不能耐受时建议行前路减压手术,整体疗效满意。     

Pattern Differences of Small Hand Muscle Atrophy in Amyotrophic Lateral Sclerosis and Mimic Disorders

Background:

Amyotrophic lateral sclerosis (ALS) and some mimic disorders, such as distal-type cervical spondylotic amyotrophy (CSA), Hirayama disease (HD), and spinobulbar muscular atrophy (SBMA) may present with intrinsic hand muscle atrophy. This study aimed to investigate different patterns of small hand muscle involvement in ALS and some mimic disorders.

Methods:

We compared the abductor digiti minimi/abductor pollicis brevis (ADM/APB) compound muscle action potential (CMAP) ratios between 200 ALS patients, 95 patients with distal-type CSA, 88 HD patients, 43 SBMA patients, and 150 normal controls.

Results:

The ADM/APB CMAP amplitude ratio was significantly higher in the ALS patients (P < 0.001) than that in the normal controls. The ADM/APB CMAP amplitude ratio was significantly reduced in the patients with distal-type CSA (P < 0.001) and the HD patients (P < 0.001) compared with that in the normal controls. The patients with distal-type CSA had significantly lower APB CMAP amplitude than the HD patients (P = 0.004). The ADM/APB CMAP amplitude ratio was significantly lower in the HD patients (P < 0.001) than that in the patients with distal-type CSA. The ADM/APB CMAP amplitude ratio of the SBMA patients was similar to that of the normal controls (P = 0.862). An absent APB CMAP and an abnormally high ADM/APB CMAP amplitude ratio (≥4.5) were observed exclusively in the ALS patients.

Conclusions:

The different patterns of small hand muscle atrophy between the ALS patients and the patients with mimic disorders presumably reflect distinct pathophysiological mechanisms underlying different disorders, and may aid in distinguishing between ALS and mimic disorders.     

Hereditary Neuralgic Amyotrophy (HNA) is genetically heterogeneous

Hereditary Neuralgic Amyotrophy (HNA) is an autosomal dominantly inherited recurrent focal neuropathy affecting mainly the brachial plexus. Linkage to markers on chromosome 17q25 was found in 1996 and subsequent reports confirmed linkage of HNA to this locus. Recently a family with a chronic undulating rather than remitting-relapsing clinical course of HNA was described by a Dutch group. This family did not have linkage to the 17q25 locus. Here we describe for the first time clinically and genetically two families with classic remitting-relapsing HNA that are not linked to the previously described HNA locus on chromosome 17q25. These results demonstrate that clinically homogeneous classical HNA is genetically heterogeneous. Received: 24 January 2001, Received in revised form: 19 March 2001, Accepted: 4 April 2001