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PubMed1982

Slowly progressive congenital myopathy with cytoplasmic bodies--report of two cases and a review of the literature.

Observations on two patients from unrelated families are reported. Both patients were 32 years old and suffered from a congenital affection of the skeletal muscles. In one (case 2) congenital paresis of the dilator muscle of pupil and cardiomyopathy were also present. In both cases muscle biopsy showed pathologic variations of muscle fiber caliber, and in case 1 atrophic fibers were grouped in some places. Inclusions consisting of dense granular and fine filamentous components were found in skeletal muscle fibers, in about a third of the fibers in case 1 and in about a tenth of the fibers in case 2. The shape and submicroscopic structure of these inclusions were consistent with so-called cytoplasmic bodies. Surrounding or apart from the inclusions, the streaming of Z disks or their disintegration were observed. In addition, pure filamentous bodies occurred in the subsarcolemmic position in both cases. Although cytoplasmic bodies are a nonspecific type of inclusion, they were the outstanding structural anomaly in both cases. A basic defect of myofilament biosynthesis is considered to be the cause of the disorder. It is presumably evoked by a neurogenic factor affecting the trophic influence of the neuron on the muscle cell. The course of the disease may (case 1) but need not (case 2) terminate in severe impairment of skeletal muscle function.

Adult↗

PubMed2001

Expression of the lysosome-associated membrane proteins in myopathies with rimmed vacuoles.

Lysosome-associated membrane proteins (LAMPs) are structural glycoproteins located on the lysosomal membrane and are thought to have an important role in protein degradation. Increased lysosomal activity is associated with the formation of rimmed vacuoles, which are observed in various muscle disorders such as inclusion body myositis (IBM) and distal myopathy with rimmed vacuole (DMRV). In the present study, we examined LAMP-1 and LAMP-2 in biopsied muscle specimens from four cases of sporadic IBM and two of DMRV, as well as six of myopathies without rimmed vacuoles. In all cases of IBM and DMRV, immunohistochemistry showed accumulation of LAMPs in the rimmed vacuoles and the subsarcolemmal portion of the vacuolated fibers. Immunoreactivities of LAMPs in the vacuolated fibers were often associated with those of cathepsin D; however, cathepsin D was not expressed on some LAMP-positive fibers. Further, atrophic muscle fibers were sometimes positive for LAMPs expression. These findings were more prominent in LAMP-2 than in LAMP-1. Thus, LAMP-2 may play an important role in the increased protein degradation in diseased muscle fibers. The increased expression of LAMPs in the vacuolated muscle fibers may be associated with the formation of rimmed vacuoles in IBM and DMRV.

Adult↗

PubMedDate not supplied

Disorders of the long head of the biceps tendon.

Without a clear understanding of the functional role of the biceps tendon, treatment recommendations have been a subject of controversy. An objective review of the available information would suggest that some humeral head stability may be imparted through the tendon. However, the magnitude of this function is likely to be small and possibly insignificant. In contrast, the symptomatic significance of the long head of the biceps is less controversial, and it has become increasingly recognized as an important source of persistent shoulder pain when not specifically addressed. When present, persistent pain from the long head of the biceps is likely to have more negative functional consequences than loss of the tendon itself. Given these concerns, evaluation and treatment of patients with long head of the biceps disorders should be individualized, based on the likelihood that biceps-related pain will resolve. Although not universally accepted, we recommend tenodesis of the long head of the biceps in those cases in which there are either chronic inflammatory or structural changes, which would make it unlikely that the pain would resolve. These clinical situations in which tenodesis would be required include greater than 25% partial thickness tearing of the tendon, chronic atrophic changes of the tendon, any luxation of the biceps tendon from the bicipital groove, any disruption of associated bony or ligamentous anatomy of the bicipital groove that would make autotenodesis likely (i.e., 4-part fracture), and any significant reduction or atrophy of the size of the tendon that is more than 25% of the normal tendon width. Relative indications for biceps tenodesis also include biceps disease in the context of a failed decompression for rotator cuff tendinitis. It should be emphasized that routine tenodesis is not recommended during operative treatment for the rotator cuff. Rather, we avoid tenodesis whenever it is believed that inflammatory changes to the biceps tendon are reversible. Because of this, tenodesis is not required in most cases.

Elbow Joint↗

PubMedDate not supplied

[Respiratory system elastance and resistance measured by proportional assist ventilation in patients with respiratory muscle weakness].

OBJECTIVE: Non-invasive ventilatory therapy has prolonged survival of myopathy patients with hypoventilation. Efficacy of non-invasive ventilation depends on both elastance and resistance of the respiratory system. Although these parameters are important in the prescription of respiratory management, conventional respiratory function test does not show the appropriate answer in patients with severe respiratory muscle weakness. In muscular dystrophy, muscle tends to be shortened due to its fibrosis, when muscle becomes atrophic and weak; fibrosis of respiratory muscle tissues presumably causes high thoracic elastance. We evaluated the total respiratory system elastance and resistance during proportional assist ventilation (PAV) in myopathy patients. METHODS: In PAV with 100% assist, using BiPAP Vision ventilator, airway pressure exceeds 20 cmH2O or tidal volume exceeds 1.5 liter (run-away phenomenon) when the volume assist or the flow assist is higher than the individual elastance or the resistance, respectively. Twenty myopathy patients with ventilatory failure and 7 healthy controls were evaluated, including 7 patients with Duchenne muscular dystrophy (DMD), 2 patients with congenital myopathy (CM), 1 patient with limb-girdle muscular dystrophy (LG), 6 patients with myotonic dystrophy (MyD) and 4 patients with acid maltase deficiency (AMD). Seventeen patients used a nasal mask and 3 patients had a tracheostomy tube. Fifteen patients used a pressure-preset ventilator, and 3 patients used a volume-preset ventilator. RESULTS: In all patients with DMD, CM and LG, respiratory system elastance was higher than 20 (cmH2O/L) and than in all patients with AMD and MyD except 1 MyD patient. Follow-up measurement after half a or one year showed increase of respiratory system elastance in 2 DMD patients and 1 CM patient, but almost no change in 3 AMD patients. The elastance measured during PAV was consistent with the clinical impression of muscle shortening. One exceptional MyD patient showed extremely high elastance (more than 58 cmH2O/L), which reflected the fixed thoracic spine and increase of abdominal visceral fat. Resistance was normal in all patients except a LG patient with pulmonary aspergillosis and a history of pulmonary tuberculosis who showed 14 (cmH2O/L/s). In a CM patient who developed emphysema, resistance increased from 5 to 12 (cmH2O/L/s) in a year, although forced expiratory volume 1.0% (FEV1.0/FVC) remained normal. Respiratory system resistance measurement was useful to detect a lung disease, because obstructive disorder is underestimated with FEV1.0/FVC when vital capacity is low. CONCLUSION: The respiratory system elastance and resistance measured during PAV are useful parameters in evaluation of mechanical features of the lung, thorax and airway. It is recommended to keep both parameters normal in patients who may require ventilatory assist due to progression of respiratory muscle weakness.

Adult↗

PubMed1984

[Disorders of venous blood flow during surgery and the postoperative period as a pathomechanism of venous thrombosis of the legs].

An increased risk of thrombosis is given in slowed movement of blood, damaged vascular wall as well as changed blood composition. The frequency of venous thrombi during and after operative interventions speaks in favour of the importance of the reduced venous return to the heart. In the operative phase the reversible negative inotropic effect of numerous anaesthetics causes a blood stasis with an increase of the filling pressure of the heart (preload) and a reduction of the effect of the Frank-Starling mechanism. While the spontaneous respiration promotes the physiological venous return to the heart, this blood flow is partly inhibited by positive pressure breathing and during opening of the thoracic cage. Also changes of the blood volume have an influence on the venous return to the heart. Additional influences are the reduced muscle tone due to anaesthetics and to muscle relaxants as well as as mechanical injury of the skeletal muscles which led to a retarded blood flow. Apart from these factors in the postoperative phase are additionally present chronic stasis appearances in front of the right heart as well as a reduction of the sensitivity of atrial receptors in the insufficient heart. Also the therapeutic use of vasoactive substances as well as the presence of a varicosis influence the flow rate in the veins. An increased risk for thrombosis also exists after bed confinement because of atrophic changes of the skeletal and vascular muscles.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia↗