Shoulder Girdle Muscles Research Articles

Body postures and asymmetries in frontal and transverse planes in the trunk area in table tennis players

The aim of this research was to assess the body posture within the trunk area in table tennis players and to estimate the correlations between the specific body posture types, their asymmetries and table tennis practice (training experience). To evaluate body posture the photogrammetric method based on the Moire phenomenon with equipment by CQ Electronic was applied. Tests of significance of difference and correlation were used to estimate the correlation of the observed asymmetries with the training experience. 40 table tennis players and 43 subjects not practising sports participated in the research. The analysis of the results revealed that table tennis players, unlike non-players, are characterized by kyphotic body posture. It probably results from a specific trunk, head and limb position during table tennis matches. Thus, many asymmetries in frontal and transverse planes were observed in the examined table tennis players. Perhaps table tennis, which is characterized by intensive and one-sided trunk muscle work during its performance, is in favour of creating asymmetries. The majority of subjects did not reveal any statistically significant correlations between the observed body posture types, their asymmetries and training experience. However, it was observed that training experience is significantly related to the considerable asymmetry of the inclination angle of shoulder line (KLB). It may result from the negative influence of very intensive, one-sided work and constant work of the shoulder girdle muscles of the playing limb with negligence of exercises of the second limb.

Hypertrophy of the Subclavius Muscle Accompanied by Atrophy of the Pectoralis Muscles Post‐mastectomy

Musculoskeletal impairments of the upper extremity following mastectomy are well documented, although the cause of these impairments is not always known. In this case study, asymmetry of the shoulder girdle musculature was found during anterior chest wall dissection of a female cadaver with a history of a left mastectomy at age 45 (age at death: 96). The left pectoralis major and minor muscles were markedly smaller than the contralateral pectoralis muscles, while the converse was apparent for the subclavius muscles (i.e. left larger than right).In situ measurements of the depth of the bellies of the subclavius muscles at distances of 5 and 7 cm from the sternoclavicular joint demonstrated that the left subclavius depth was nearly twice that of the right (at 5 cm: R=5mm, L=10mm; at 7 cm: R=8mm, L=15 mm). Measurements of the length and wet weight of the muscles confirmed both the increased size and mass of the left subclavius (length: R=8.5 cm, L=10.5 cm; weight: R=1.2 g, L=3.3 g).The pattern of atrophy of the pectoralis muscles suggests that the medial pectoral nerve was damaged during surgery or during post‐operative treatment. How this led to the apparent hypertrophy of the left subclavius muscle is unclear. It is possible that because of the atrophy and associated weakness of the left pectoralis muscles, the left subclavius muscle took on a greater role in shoulder girdle stabilization, increasing in size and mass over time.

Visual Vignette

Case Presentation: A 30-year-old man presented with progressively worsening weakness of both shoulder girdle muscles associated with wasting for a period of 1 year. The patient had initially noticed muscle aches followed by easy fatigability in using both arms and also difficulty in climbing stairs. There was no history to suggest involvement of the distal muscles of the extremities or pharyngeal, neck, trunk, or ocular muscles. He indicated that he had gained 4 kg during a 1-year period and had periorbital puffiness.

Musculotopic organization of the motor neurons supplying forelimb and shoulder girdle muscles in the mouse

We identified the motor neurons (MNs) supplying the shoulder girdle and forelimb muscles in the C57BL/6J mouse spinal cord using Fluoro-Gold retrograde tracer injections. In spinal cord transverse sections from C2 to T2, we observed two MN columns (medial and lateral) both with ventral and dorsal subdivisions. The dorsolateral column consisted of the biceps brachii, forearm extensors, forearm flexors, and hand MNs, and the ventrolateral column consisted of the latissimus dorsi, trapezius, teres major, deltoid, and triceps MNs. The supraspinatus muscle MNs were located in the dorsomedial column, and pectoralis major and serratus anterior MNs were located in the ventromedial columns. MNs of the dorsolateral column innervated the biceps brachii in mid-C4 to mid-C7, forearm extensors in caudal C4 to mid-T1, forearm flexors in rostral C5 to mid-T1, and hand muscles in mid-C8 to mid-T2 segments. The MNs innervating the trapezius were located in mid-C2 to mid-C4, triceps brachii in mid-C6 to rostral T1, deltoid in rostral C4 to mid-C6, teres major in rostral C5 to mid-C8, and latissimus dorsi in mid-C5 to caudal C8. In addition, MNs innervating the supraspinatus were located from rostral C4 to caudal C8, pectoralis major in mid-C6 to mid-T2, and serratus anterior in rostral C5 to caudal C7/rostral C8 segments. While the musculotopic pattern of MN groups was very similar to that documented for other species, we found differences in the position and cranio-caudal extent of some MN pools compared with previous reports. The identification of mouse forelimb MNs can serve as an anatomical reference for studying degenerative MN diseases, spinal cord injury, and developmental gene expression.

1106 The clinical phenotypic spectrum of GFPT1 associated congenital myasthenic syndrome

We report on the clinical features of a distinct group of DOK 7 negative limb girdle congenital myasthenic syndrome (LG-CMS), the cause of which has only recently been unravelled. Congenital...

The effect of clavicle malunion on shoulder biomechanics; A computational study

BackgroundClavicle malunion affects the biomechanics of the shoulder joint. The purpose of this study is to establish the abduction, flexion, and internal (medial) rotation biomechanics of the shoulder after clavicle malunion. MethodsA computational study was performed utilizing a three-dimensional, validated computational model of the upper extremity. Sequential shortening of the clavicle up to 20% was simulated. Muscle forces, moment arms, and moments were calculated for the surrounding musculature through a range of flexion, abduction, and internal rotation during the simulated shortening. FindingsShortening of the clavicle decreases the shoulder elevation moments of the upper extremity muscles during abduction. Internal rotation moments are also decreased with shortening. Flexion moments were affected less through physiologic range of motion. The observed effects are due to a combination of changes in moment arms of the individual muscles as well as a decrease in the force generating capacity of the muscles. Additionally, shortening of the clavicle increases coronal angulation of the clavicle at the sternoclavicular joint. InterpretationShortening causes a decrease in the moment generating capacity as well as the total force generating capacity of the shoulder girdle muscles. The clinical significance of these computational results, which are consistent with recent clinical studies, is validation of the proposed functional deficit caused by clavicle malunion.

Endurance to physical strain in patients with temporomandibular disorders: a case-control study

Objective. The hypothesis tested was whether patients with temporomandibular disorders (TMD) have an impaired endurance to motor tasks, under physical strain. Material and methods. The study population included 81 cases with TMD and 75 controls. After giving their informed consent, the participants filled out a questionnaire and performed five endurance trials. Each trial was measured in seconds from start to termination. The tests included: (a) holding the arm in a straight out position with a 2 kg weight in the hand, (b) lifting and lowering the arm with a 2 kg weight in the hand, (c) opening and closing the mandible repeatedly against a resistance of 1.6 kg during the jaw-opening phase, (d) protruding and retracting the mandible repeatedly against a resistance of 1.6 kg during the protruding phase and (e) unilateral chewing of three pieces of chewing gum. Analysis of differences between cases and controls for endurance were evaluated with Mann-Whitney U-test. A p-value < 0.05 was considered statistically significant. Results. The cases had statistically significantly (p < 0.0001) lower endurance time than controls for all tests. Conclusions. Patients with TMD compared to those without signs and symptoms of TMD have an impaired capacity to endure motor tasks that involve physical demand of the jaw muscles and shoulder girdle muscles.

AAV6-mediated Systemic shRNA Delivery Reverses Disease in a Mouse Model of Facioscapulohumeral Muscular Dystrophy

Treatment of dominantly inherited muscle disorders remains a difficult task considering the need to eliminate the pathogenic gene product in a body-wide fashion. We show here that it is possible to reverse dominant muscle disease in a mouse model of facioscapulohumeral muscular dystrophy (FSHD). FSHD is a common form of muscular dystrophy associated with a complex cascade of epigenetic events following reduction in copy number of D4Z4 macrosatellite repeats located on chromosome 4q35. Several 4q35 genes have been examined for their role in disease, including FRG1. Overexpression of FRG1 causes features related to FSHD in transgenic mice and the FRG1 mouse is currently the only available mouse model of FSHD. Here we show that systemic delivery of RNA interference expression cassettes in the FRG1 mouse, after the onset of disease, led to a dose-dependent long-term FRG1 knockdown without signs of toxicity. Histological features including centrally nucleated fibers, fiber size reduction, fibrosis, adipocyte accumulation, and inflammation were all significantly improved. FRG1 mRNA knockdown resulted in a dramatic restoration of muscle function. Through RNA interference (RNAi) expression cassette redesign, our method is amenable to targeting any pathogenic gene offering a viable option for long-term, body-wide treatment of dominant muscle disease in humans.

Elastisch stabile intramedulläre Nagelung nach Korrekturosteotomie von symptomatisch fehlverheilten Klavikulafrakturen

To restore alignment and length of the clavicle, to relieve typical symptoms of malunion, and to improve functional outcome and aesthetic results. Symptomatic malunion after clavicular fractures, including local pain and tenderness, weakness and rapid fatigability of the shoulder girdle muscles, impairment of overhead mobility, numbness, parasthesia, and pain of the arm and fingers during overhead movements due to brachial plexus irritation (thoracic outlet syndrome), and dissatisfaction with the appearance of the shoulder girdle. Atrophic nonunions, osteoporosis, asymptomatic malunion. A 5-cm skin incision is made above the deformity of the malunited clavicle. The osteotomy plane is determined under fluoroscopic guidance, within the callus separating the two original main fracture fragments. Under fluoroscopic guidance, the medullary canal is reopened on both sides with a 2.7mm drill bit. Afterwards a 1.5cm skin incision is made just above the sternal end of the clavicle. The anterior cortex is drilled and a titanium nail (diameter 2.5mm) is introduced. Under rotational movement, the nail is advanced to the osteotomy site. The nail is inserted into the lateral fragment. Then the inserted nail is cut back as far as possible on the medial entry point. Wound closure. No immobilization, movement not restricted. Patients are encouraged to use the arm in daily activities. Heavy weight bearing is not allowed until osseus consolidation. In 5patients (3men, 2women) with a mean age of 34years (range, 23-44years) with symptomatic malunion after clavicular fractures, a corrective osteotomy and elastic stable intramedullary nailing (ESIN) was performed. After 6months (mean 4.4months), all osteotomies were healed and the nails were removed. There were no complications. At final follow-up (12months), the DASH and Constant scores were significantly improved compared to preoperative values. Patients were significantly more satisfied with the appearance of the shoulder girdle and overall outcome.

FSHD myoblasts fail to downregulate intermediate filament protein vimentin during myogenic differentiation

Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant hereditary neuromuscular di- sorder. The clinical features of FSHD include weakness of the facial and shoulder girdle muscles followed by wasting of skeletal muscles of the pelvic girdle and lower extremities. Although FSHD myoblasts grown in vitro can be induced to differentiate into myotubes by serum starvation, the resulting FSHD myotubes have been sho- wn previously to be morphologically abnormal. Aim. In order to find the cause of morphological anomalies of FSHD myotubes we compared in vitro myogenic differentiation of normal and FSHD myoblasts at the protein level. Methods. We induced myogenic differentiation of normal and FSHD myoblasts by serum starvation. We then compared protein extracts from proliferating myoblasts and differentiated myotubes using SDS-PAGE followed by mass spectrometry identification of differentially expressed proteins. Results. We demonstrated that the expression of vimentin was elevated at the protein and mRNA levels in FSHD myotubes as compared to nor- mal myotubes. Conclusions. We demonstrate for the first time that in contrast to normal myoblasts, FSHD myo- blasts fail to downregulate vimentin after induction of in vitro myogenic differentiation. We suggest that vi- mentin could be an easily detectable marker of FSHD myotubes.

O.19 Facioscapulohumeral muscular dystrophy: Muscle running out of control

Facioscapulohumeral muscular dystrophy (FSHD) is a common muscular dystrophy characterized by progressive and often asymmetric weakness and wasting of facial, shoulder girdle and upper arm muscles. FSHD is caused by a local the chromatin relaxation of the D4Z4 repeat array which results in the transcriptional derepression of the DUX4 retrogene. The chromatin relaxation can be initiated by contraction of the D4Z4 repeat array (FSHD1), or by a yet unknown chromatin modifier (FSHD2), but only leads to detectable levels of DUX4 when the repeat array is localized on a specific permissive genetic background of chromosome 4q.

Shoulder Arthrodesis for Treatment of Flail Shoulder in Children With Polio

Poliomyelitis in children can cause paralysis of shoulder girdle muscles leading to a flail shoulder. Shoulder arthrodesis is indicated as a possible treatment for these children in order to stabilize the shoulder. This retrospective study reviewed all shoulder arthrodesis surgeries owing to complications of polio performed at a major medical institution between 1981 and 1996 to assess position of fusion, radiographic evidence of fusion, complications, and patient satisfaction. A review of medical records identified 11 patients undergoing 13 shoulder arthrodesis procedures, with a mean age of 14.7 years at the time of the procedure. Internal fixation was achieved with large cancellous screws in 8 patients and a Dynamic Compression Plate (DCP) plate in 5 procedures. Average follow-up period was 41 months. Eight patients were placed into a spica cast and 5 used a sling postoperatively. Shoulder arthrodesis surgery in this cohort resulted in an average position of fusion with 42.3 degrees of abduction, 23.8 degrees of flexion, and 26.2 degrees of internal rotation. Twelve of the 13 procedures assessed for radiographic union demonstrated fusion. The most common complications were malrotation and nonunion. Of the 13 procedures, 2 underwent humeral osteotomies for malrotation, and 1 with 6.5 mm cancellous screws required revision with a DCP plate owing to nonunion. Six patients underwent hardware removal, 3 of which were specifically owing to complaints of painful hardware. At final follow-up, no patient reported pain and all expressed satisfaction with their results and improved shoulder function after repair. This study is the largest series of shoulder arthrodesis surgeries for treatment of patients with a flail shoulder from polio to date, providing a more thorough analysis of its efficacy as an indicated treatment. Level III-Retrospective Comparative Study.

Anti-Signal Recognition Particle Myopathy in the First Decade of Life

Autoantibodies to signal recognition particle have been associated with juvenile and adult-onset necrotizing myopathy. However, only a few teenage patients with anti-signal recognition particle myopathy have been reported, and to date, to our knowledge, no patient younger than 10 years has been documented. We describe 2 Japanese girls with anti-signal recognition particle myopathy who developed symptoms from the ages of 5 and 9 years, respectively. Both patients had progressive muscle weakness and atrophy without myalgia. Facioscapulohumeral muscular dystrophy was initially suspected because of asymmetric shoulder girdle muscle involvement in one patient, and limb girdle muscular dystrophy due to proximal limb muscle weakness in the other. There were no extramuscular manifestations, including fever or arthritis. Serum creatine kinase levels were elevated to 2,467-4,629 IU/L. Results of muscle biopsy revealed necrotizing myopathy with minimal to mild endomysial fibrosis but without inflammatory infiltrates. Immunosuppressive agents were not effective for muscle weakness, resulting in marked disability. Anti-signal recognition particle myopathy can occur in the first decade of life and should be included in the differential diagnosis for children with progressive limb girdle muscle weakness and high creatine kinase levels.

Shoulder impairments and their association with symptomatic rotator cuff disease in breast cancer survivors

Over 2.6 million breast cancer survivors currently reside in the United States. While improvements in the medical management of women diagnosed with breast cancer have resulted in a 5-year survival rate of 89%, curative treatments are associated with a high prevalence of shoulder and arm morbidity, which, in turn, can negatively impact a woman’s quality of life. Breast cancer survivors frequently experience shoulder and arm pain, decreased range of motion, muscle weakness, and lymphedema. These symptoms can lead to difficulties with daily activities ranging from overhead reaching and carrying objects to caring for family and returning to work. Despite health care professionals awareness of these problems, a significant number of breast cancer survivors are confronted with long-term, restricted use of their affected shoulder and upper extremity. This problem may partially be explained by: (1) an incomplete understanding of relevant impairments and diagnoses associated with shoulder/arm pain and limited upper extremity use, and (2) the limited effectiveness of current rehabilitation interventions for managing shoulder pain and decreased upper extremity function in breast cancer survivors. Because breast cancer treatment directly involves the neuromusculoskeletal tissues of the shoulder girdle, it is understandable why breast cancer survivors are likely to develop shoulder girdle muscle weakness and fatigue, decreased shoulder motion, altered shoulder girdle alignment, and lymphedema. These impairments can be associated with diagnoses such as post-mastectomy syndrome, adhesive capsulitis, myofascial dysfunction, and brachial plexopathy, all of which have been reported among breast cancer survivors. It is our belief that these impairments also put women at risk for developing symptomatic rotator cuff disease. In this paper we set forth the rationale for our belief that breast cancer treatments and subsequent impairments of shoulder girdle neuromusculoskeletal tissues place breast cancer survivors at risk for developing symptomatic rotator cuff disease. Additionally, we identify knowledge gaps related to the current understanding of relevant shoulder girdle impairments and their association with symptomatic rotator cuff disease in breast cancer survivors. Ultimately, information from studies designed to meet these gaps will provide a scientific basis for the development of new, or refinement of existing, examination, intervention, and prevention techniques, which should lead to improved clinical outcomes in this population.

Zastosowanie manualnych technik fizjoterapeutycznych w rehabilitacji dysfonii pourazowej

As a result of laryngeal injures an abnormal phonation is frequently observed. It is the consequence of structural and functional changes of the laryngeal tissues directly and indirectly responsible for the voice emission. Physiotherapy enables the normalization of the tension and function of the anatomical structures changed after trauma. Presentation of the results of the physiotherapy and voice rehabilitation treatment established for patient with voice disorders, occurred after cranio-cerebral trauma. The 47 year old man two years after cranio-cerebral trauma was presented, which voice was hoarse, produced with a strong neck and shoulder girdle muscle tension. Phonation time was significantly shortened. During the manual examination the abnormal of mobility, range of movement and soft tissue tension in neck, head and upper trunk area has been observed. The systematic rehabilitation program was started 2 years after injury and it was continued for four months. The individual program contains physiotherapy, osteopathic and speech therapy treatment. The phoniatric examination was performed before and after rehabilitation After four months of treatment and after self-therapy exercises the significant changes were observed. Patient's voice became no more strain, but stronger and socially effective. The application of an individual therapy which contained osteopathic manual muscle-fascial techniques allows a subjective and objective improvement of voice in a examined patient. This procedure is an effective complement to logopedic and phoniatric therapy for patients after trauma of the larynx.

Case Study: Use of the Dynamic Movement Orthosis to Provide Compressive Shoulder Support for Children With Brachial Plexus Palsy

Children with obstetric brachial plexus palsy often present with shoulder alignment issues. Shoulder subluxation may occur as a result of shoulder girdle muscle weakness and overstretching of the ligamentous support structure around the glenohumeral joint. Optimal alignment and support of the glenohumeral joint is essential for active functional shoulder movement and distal control. Shoulder support options are limited for children, because materials may not be suitable for daily wear and compliance is often poor. The purpose of this case study was to evaluate the effectiveness of a custom-fitted shoulder orthosis, the Dynamic Movement Orthosis (DMO), and its ability to support and improve upper limb function during active wear. The Wolf Motor Function Test assesses 17 tasks (2 strength based, measured by weight lifted and grip, and 15 function based, measured using time to completion). This test was used to objectively quantify active shoulder and elbow movements with and without the use of a custom-fitted DMO. This case study suggests that the DMO supported the shoulder during functional task and optimized active strength distally in the wrist and elbow. (J Prosthet Orthot. 2011;23:159‐164.) KEY INDEXING TERMS: shoulder orthosis, brachial plexus palsy, shoulder weakness, shoulder subluxation, shoulder brace, obstetric brachial plexus palsy

Congenital Acquired Atrophy of the Shoulder Girdle Muscles in a Patient with Sprengel's Deformity

INTRODUCTION Sprengel’s deformity is a congenital anomaly of the shoulder girdle which results in elevation of the scapula (congenital high scapula) and limitation of movement of the shoulder. Sprengel’s deformity is the most common congenital malformation of the shoulder girdle, with a male to female ratio of 3:1. It is frequently associated with cervical spine malformations, absent or hypoplastic periscapular musculature, and abnormalities in the cervicothoracic vertebrae or thoracic rib cage: absent or fused ribs, chest wall asymmetry, Klippel-Feil syndrome, cervical ribs, congenital scoliosis, and cervical spina bifida. The hallmark of Sprengel’s deformity is shoulder asymmetry with restriction of shoulder abduction. The elevation of the scapula is accompanied by its rotation to various positions. Clinically, the affected scapula is usually elevated 2 to 10 cm, adducted, and its inferior pole is medially rotated. The left side is more commonly affected but may sometimes be bilateral, in which case it is more functionally disabling, although it is cosmetically much more acceptable. No satisfactory explanation exists regarding the pathogenesis of Sprengel’s deformity. It is thought to be the consequence of teratogenic exogenous or endogenous harmful agent affecting mesenchymal tissue in the fourth to fifth week of embryogenesis. There may be hereditary forms. There is underdevelopment and degeneration of the shoulder girdle muscles and creation of abnormal omovertebral fibrous, cartilaginous or osseous connection, such as the presence of an omovertebral bone seen in approximately one-third of patients. The hypoplastic scapula is usually tethered to the spine and posterior ribs by tight bands or by the omovertebral bone, which restricts scapular movements, and therefore abduction of the arm. The diagnosis of Sprengel’s deformity is based on clinical examination and radiological findings. It is uncommon to identify an adult with untreated Sprengel’s deformity, like the patient who presented here. Most patients with Sprengel’s deformity receive surgical treatment as children or adolescents. Adult patients with childhood polio, an acquired cause of weakness of the shoulder girdle, may present later in life with symptoms and signs of thoracic outlet syndrome with worsening of the weakness. The accompanying pain and sensory symptoms such as tingling and “numbness” would mitigate against a diagnosis of post polio syndrome in these patients.

High prevalence of shoulder girdle muscles with myofascial trigger points in patients with shoulder pain

BackgroundShoulder pain is reported to be highly prevalent and tends to be recurrent or persistent despite medical treatment. The pathophysiological mechanisms of shoulder pain are poorly understood. Furthermore, there is little evidence supporting the effectiveness of current treatment protocols. Although myofascial trigger points (MTrPs) are rarely mentioned in relation to shoulder pain, they may present an alternative underlying mechanism, which would provide new treatment targets through MTrP inactivation. While previous research has demonstrated that trained physiotherapists can reliably identify MTrPs in patients with shoulder pain, the percentage of patients who actually have MTrPs remains unclear. The aim of this observational study was to assess the prevalence of muscles with MTrPs and the association between MTrPs and the severity of pain and functioning in patients with chronic non-traumatic unilateral shoulder pain.MethodsAn observational study was conducted. Subjects were recruited from patients participating in a controlled trial studying the effectiveness of physical therapy on patients with unilateral non-traumatic shoulder pain. Sociodemographic and patient-reported symptom scores, including the Disabilities of the Arm, Shoulder, and Hand (DASH) Questionnaire, and Visual Analogue Scales for Pain were compared with other studies. To test for differences in age, gender distribution, and education level between the current study population and the populations from Dutch shoulder studies, the one sample T-test was used. One observer examined all subjects (n = 72) for the presence of MTrPs. Frequency distributions, means, medians, standard deviations, and 95% confidence intervals were calculated for descriptive purposes. The Spearman's rank-order correlation (ρ) was used to test for association between variables.ResultsMTrPs were identified in all subjects. The median number of muscles with MTrPs per subject was 6 (active MTrPs) and 4 (latent MTrPs). Active MTrPs were most prevalent in the infraspinatus (77%) and the upper trapezius muscles (58%), whereas latent MTrPs were most prevalent in the teres major (49%) and anterior deltoid muscles (38%). The number of muscles with active MTrPs was only moderately correlated with the DASH score.ConclusionThe prevalence of muscles containing active and latent MTrPs in a sample of patients with chronic non-traumatic shoulder pain was high.

Fazioskapulohumerale Muskeldystrophie

The classic phenotype of the facioscapulohumeral muscular dystrophy (FSHD) includes an initially restricted pattern of asymmetric weakness of facial and shoulder girdle muscles. Disease progression is usually slow and typically accompanied by foot extensor muscle weakness and pelvic girdle weakness. Atypical patterns of FSHD that include isolated camptocormia and facial muscle sparing exceed current diagnostic criteria. No causal genetic lesion in FSHD has been identified yet. In the vast majority of cases, FSHD results from a heterozygous partial deletion of a critical number of repetitive elements (D4Z4) on chromosome 4q35 (4qA allele). Molecular diagnostic testing is appropriate to confirm the diagnosis of FSHD without need for muscle biopsy. Penetrance of this dominantly inherited disorder is high, exhibiting a great phenotypic variability in clinical pattern and disease progression even among affected members of the same family.

Lobulated fibers in a patient with 46‐year history of limb‐girdle muscle weakness

A 78-year-old man presented with a 46-year history of slowly progressive muscle weakness. He had a past medical history of hypertension but had no familial history of neuromuscular disorders. He first noticed mild muscle weakness affecting his thigh at the age of 32 when he could not keep up with others during mountain climbing. The proximal muscle weakness worsened gradually to difficulty in climbing stairs after the age of 40, and progressed to involve his upper extremities when he could not raise his arms after the age of 50. When he first visited the clinic at the age of 57, physical examination revealed proximaldominant and symmetric muscle weakness with atrophy in his four limbs, pelvic and shoulder girdle muscles. He had no facial muscle involvement or calf muscle hypertrophy. He neither had cardiac nor respiratory abnormality. Serum creatine kinase (CK) level was 1774 (normal <200) IU/L. Electromyography was reported to be myogenic. He was diagnosed by skeletal muscle biopsy and genetic analysis at the age of 58. It became increasingly difficult for him to stand up at the age of 63. He started using a wheelchair but still could walk with a hand-rail at the age of 66. He could drive a car until the age of 74. Since the age of 75, he has been wheelchair-bound.