Muscular Abnormalities Research Articles

SY. EMG in myositis

Summary1.The clinical findings in a case of myotonia congenita (Thomsen's disease) are presented.2.Attempts at demonstrating a myotonia-inducing substance in the bloodof the patient are described. These attempts were unsuccessful.3.The myotonic pattern of response was uninfluenced by complete curarizationof the patient. The significance of this in the localization of the muscular abnormality is discussed.

Magnetic resonance imaging of the normal and pathologic muscular system

Evaluation of the muscular system with magnetic resonance (MR) was conducted: (1) to assess the capability of MR to depict muscular abnormalities; (2) to evaluate the ability of MR to discriminate between various types of muscular pathologies based on relaxation parameters; and (3) to determine the optimal spin echo (SE) sequence that produced optimal contrast. Retrospective analysis was performed on 59 consecutive patients with a variety of muscular abnormalities. MR muscle analysis included visual inspection of contour and size; muscle intensity changes in relation to various TR TE combinations; measurement of T1 and T2 relaxation and spin density; and calculation of percent contrast variation with different SE imaging combinations. Contour and size abnormalities were not reliable for detection of muscular pathology. For each individual subject intensity and relaxation times of all muscles involved by pathology differed from normal muscle. Although all pathologies caused increase in signal intensity of muscle, the alterations in relaxation times were variable. Fatty atrophy caused a decrease in T1 and increase in T2; while post-surgical changes, infection, acute intramuscular hemorrhage, and tumor invasion caused an increase in both T1 and T2. Percent contrast indicated that the optimum sequence for evaluation of fatty atrophy was a short (0.5 sec) repetition time (TR) and echo delay time (TE) of 56 msec, while for demonstration of the remaining muscular abnormalities, including post-surgical changes, infection, acute intramuscular hemorrhage, and tumor invasion, a long TR (TR = 2.0 sec) and TE (56 msec) was optimal. Differentiation between various benign and malignant muscular abnormalities (excluding fatty atrophy) was not possible using either quantitative intensity values or relaxation times.

Misplaced epithelium in ulcerative colitis and Crohn's disease of the colon and its relationship to malignant mucosal changes.

The presence of misplaced mucosal epithelium was studied in the colectomy specimens from 30 patients with Crohn's disease, 30 patients with ulcerative colitis, 15 patients with ulcerative colitis complicated by carcinoma and 30 patients with non-colitic colorectal carcinoma. Misplaced epithelium was present in 21 (70%) of the resection specimens with Crohn's disease, 20 (66.7%) with ulcerative colitis and 12 (80%) with ulcerative colitis complicated by carcinoma. None of the specimens with non-colitic colorectal adenocarcinoma showed misplaced foci of epithelium. Two pathogenetic mechanisms for epithelial misplacement are proposed: (1) the effects of mucosal inflammation and repair; and (2) muscular abnormalities in inflammatory bowel disease. The proposed mechanisms and patterns of epithelial misplacement are discussed and illustrated. The importance of its recognition is emphasized because, when associated with mucosal dysplasia, difficulties in interpretation arise in distinguishing it from 'early' invasive adenocarcinoma. Epithelial misplacement is common in patients with longstanding ulcerative colitis and may be a factor in increasing the significance of pre-existing mucosal dysplasia and promoting the development of adenocarcinoma. This may explain the unusual growth pattern encountered in ulcerative colitis, of submucosal cancer underlying a flat, non-dysplastic mucosa.

Elastosis in diverticular disease of the sigmoid colon.

Diverticular disease of the sigmoid colon is an increasingly common clinical problem in the ageing population of western industrialised countries but the mechanism by which the disease develops remains unknown. The muscular abnormality is the most striking and consistent feature and this has been studied by light and electron microscopy in 25 surgical specimens of uncomplicated diverticular disease and in 25 controls. This is the first ultrastructural study of human colonic muscle to be published and shows that the muscle cells in diverticular disease are normal; neither hypertrophy nor hyperplasia is present. There is, however, an increase in the elastin content of the taeniae coli by greater than 200% compared with controls: elastin is laid down between the muscle cells and the normal fascicular pattern of the taeniae coli is distorted. There is no alteration in the elastin content of the circular muscle. As elastin is laid down in a contracted form, this elastosis may be responsible for the shortening or 'contracture' of the taeniae which in turn leads to the characteristic concertina-like corrugation of the circular muscle. Such a structural change could explain the altered behaviour of the colon wall in diverticular disease and its failure to change on treatment with bran.

Muscular abnormalities in experimental hypothyroidism of rats with special reference to the mounding phenomenon

The mounding phenomenon was examined in vitro on the excised extensor digitorum longus or soleus muscle of hypothyroid rats. The mounding phenomenon was more prominent and lasted longer in hypothyroid muscles than in controls. In single skinned muscle fibers of both type 1 and type 2 from hypothyroid animals, the maximum tension produced by Ca ion was reduced and activity of Ca uptake by the sarcoplasmic reticulum was also decreased, judging from the response to caffeine. Decreased Ca uptake might retard the relaxation of contracture, thereby rendering the mounding more prominent. Morphological studies of both extensor digitorum longus and soleus muscles showed an increase of type 1 muscle fiber population as well as mild changes in arrangement of the internal membrane system. However, there was no muscle necrosis or other derangements. These results supported the idea that functional abnormality of the sarcoplasmic reticulum could be the basis of the exaggeration of the mounding phenomenon in hypothyroidism.

Abnormalities of muscle fibers in maple syrup urine disease.

Muscle fiber abnormalities are described in three cases of neonatal maple syrup disease. There were important variations in fiber diameters. Lesions consisted in focal or diffuse destruction of myofibrils. In view of recent biochemical and clinical data, a direct relation between elevated branched-chain amino acid levels and the muscular abnormalities seems improbable.

Bovine progressive degenerative myeloencephalopathy ('weaver') of Brown Swiss cattle II

An epidemiological survey of this nervous disorder of the Brown Swiss breed in the USA did not implicate any geographical or environmental factors. There was no sex predilection. The number of recorded cases increased from four in 1972-76 to 46 in 1977-81. There were 32 cases in 1982-83. Breeding records from over half the cases indicated a familial pattern involving five sires. Studies on 32 affected purebred Brown Swiss cattle obtained from dairy farms throughout the USA are described. Owners supplied histories and breeding records, and blood typing was carried out to confirm parentage. The criteria used to establish a clinical diagnosis were: onset of bilateral hind leg weakness and ataxia between 5 and 8 months of age; deficient proprioceptive reflexes, normal motor and sensory reflexes, with no other clinically detectable neurological abnormality; and absence of clinically significant skeletal or muscular abnormality. Familial relationship was also taken into account. Laboratory studies included at least one blood count, routine serum chemistry, serum enzyme levels, and analysis of CSF, and selected cattle were screened for toxicological abnormalities. Three sires were incriminated in 48.6% of the cases, and one was incriminated in 31.4%. Laboratory analyses revealed no abnormal haematological parameters. Although increased activities of certain serum enzymes were found, these were not considered specific. CSF samples from two cases showed CPK activity. Toxicological analyses of cholinesterase activity and blood Cu levels were not significant.

Bovine progressive degenerative myeloencephalopathy ('weaver') of Brown Swiss cattle I

An epidemiological survey of this nervous disorder of the Brown Swiss breed in the USA did not implicate any geographical or environmental factors. There was no sex predilection. The number of recorded cases increased from four in 1972-76 to 46 in 1977-81. There were 32 cases in 1982-83. Breeding records from over half the cases indicated a familial pattern involving five sires. Studies on 32 affected purebred Brown Swiss cattle obtained from dairy farms throughout the USA are described. Owners supplied histories and breeding records, and blood typing was carried out to confirm parentage. The criteria used to establish a clinical diagnosis were: onset of bilateral hind leg weakness and ataxia between 5 and 8 months of age; deficient proprioceptive reflexes, normal motor and sensory reflexes, with no other clinically detectable neurological abnormality; and absence of clinically significant skeletal or muscular abnormality. Familial relationship was also taken into account. Laboratory studies included at least one blood count, routine serum chemistry, serum enzyme levels, and analysis of CSF, and selected cattle were screened for toxicological abnormalities. Three sires were incriminated in 48.6% of the cases, and one was incriminated in 31.4%. Laboratory analyses revealed no abnormal haematological parameters. Although increased activities of certain serum enzymes were found, these were not considered specific. CSF samples from two cases showed CPK activity. Toxicological analyses of cholinesterase activity and blood Cu levels were not significant.

Immunological abnormalities in a family with progressive external ophthalmoplegia

The authors report the muscular and humoral immunological abnormalities found in a family with progressive external ophthalmoplegia (PEO) of the “pure” form. Serum circulating immune complexes as determined by the polyethylen glycol (PEG) test and double radial immunodiffusion (DRID) were positive for IgG in both cases studied and for IgM and Clq for the propositus. In the latter circulating auto-antibodies against smooth muscle were also present. Immunohistochemical studies on striated muscle of the propositus showed positive perivascular IgG and IgM staining and IgG in the sarcolemma-basement membrane complex. It is suggested that in this family a genetically inherited abnormal immune response to the muscular blood vessel wall has induced vascular injury and ultimately chronic ischemic muscular damage. This is consistent with the view that PEO is a clinical syndrome, i.e. the expression of various defects affecting primarily or secondarily the energy metabolism of the muscular tissue.

Profound Hypokalemia in Continuous Ambulatory Peritoneal Dialysis

Symptomatic hypokalemia is not known to complicate continuous ambulatory peritoneal dialysis (CAPD), although this treatment is associated with continuous peritoneal potassium losses. Severe hypokalemia and muscular abnormalities associated with potassium loss developed in a patient undergoing CAPD, illustrating that oral supplementation and/or intraperitoneal potassium administration may be needed to treat patients with chronically poor nutritional intake or increased gastrointestinal potassium losses. Intraperitoneal potassium administration may be indicated in patients who cannot tolerate oral potassium supplements.

Benign X-linked myopathy with acanthocytes (McLeod syndrome). Its relationship to X-linked muscular dystrophy.

Two healthy men with McLeod syndrome, a rare X-linked recessive phenotype characterized by acanthocytosis and weakened red blood cell antigenicity in the Kell blood group system, have been investigated. Both men showed raised blood creatine kinase levels, with myopathic EMG abnormalities. Biopsies of the quadriceps muscle showed the features of an active myopathy although there was no clinical evidence of muscular abnormality. The combination of the association of membrane abnormalities in red blood cells and a myopathy in both McLeod phenotype and Duchenne muscular dystrophy suggests that these syndromes may be due to related genetic abnormalities. The genetic locus for McLeod phenotype is situated near the end of the short arm of the X chromosome. The locus for Duchenne muscular dystrophy is unknown but it has been postulated that it is also situated on the short arm of the X chromosome at Xp 21. The occurrence of a subclinical X-linked myopathy with acanthocytosis (McLeod phenotype) thus raises the possibility of a new approach to genetic investigations in Duchenne muscular dystrophy, and in the related milder forms of this disease.

A Psychophysiological Investigation of Tension Headache

SYNOPSISIn a psychophysiological investigation of tension headache cases (n = 23) with migraine headache controls (n = 10) and non‐headache controls (n = 30), both tonic and phasic activity of the key muscles (frontalis and temporalis) and the temporal artery pulse were examined. Although all headache cases had significantly elevated levels of temporalis tension, tension headache sufferers were not differentiated from migraine in this respect. A substantial subgroup of tension sufferers (30%) had no detectable muscular or arterial abnormality associated with their severe pain. Idiosyncratic stress stimuli evoked significant frontalis reactivity in all headache cases (tension and migraine). These responses were triggered only by potent stimuli. Migraine cases had higher level of temporal artery abnormality at rest, in response to stress, and during pain episodes than tension cases. The implications of these results were discussed with respect to the prevailing view of tension headaches. An alternative model of this disorder was considered.

An unusual extraocular muscle anomaly in a patient with Crouzon's disease.

A 29-year-old female suffering from Crouzon's disease was admitted to hospital with retinal detachment in the right eye. At operation agenesis of 4 extraocular muscles (superior and inferior recti and obliquus) was found, together with abnormal insertion of the 2 horizontal muscles. The same extraocular muscular abnormalities were found in the left eye. We suggest here a new surgical treatment in such cases and discuss the reasons for the limitation of ocular motility in such cases.

IS FETAL RESPIRATORY FUNCTION A MAJOR DETERMINANT OF PERINATAL SURVIVAL?

A high proportion of infants who die in the perinatal period have undersized lungs of reduced weight and DNA content relative to body weight. Failure of formation or leakage of amniotic fluid causes a spectrum of changes varying from severe failure of growth and maturation of the lung to a predominantly maturational deficiency. The changes are associated with narrow airways suggesting a failure to secrete or retain lung liquid. Conditions in which there is reduction of thoracic volume, or certain neural and muscular abnormalities, are associated with failure of lung growth without impaired maturation. Studies in animals indicate that liquid secretion into the fetal airways and breathing movements are essential for normal lung growth. Such functions are readily inhibited by operations, drugs, or non-specific forms of stress. The success or failure of adaptation to extrauterine respiration may often be determined by the balance of factors influencing respiratory function in early fetal life.

The pronator teres syndrome

Thirty-nine patients with a clinical diagnosis of the pronator teres syndrome were seen during a seven-year period. They typically complained of aching discomfort in the forearm, weakness in the hand, and numbness in the thumb and index finger. Cyclic stress usually brought on the symptoms. The distinctive physical finding was tenderness over the proximal part of the pronator teres, which was aggravated by resisted pronation of the forearm, flexion of the elbow, and occasionally by resisted contraction of the flexor superficialis of the long finger. Electrophysiological testing of the median nerve showed abnormalities in a few patients, but localization of the abnormality was possible only rarely. Intraoperative recordings showed some improvement shortly after release of the median nerve in six of the ten forearms that were tested. Surgical exploration of thirty-six forearms in thirty-two patients showed intramuscular tendinous bands in the pronator, indentation of the muscle belly of the flexor superficialis in most forearms. Vascular and muscular abnormalities were seen occasionally. Of the thirty-six operations, twenty-eight gave good or excellent results; five, fair; and in three patients the symptoms were unchanged. The cause of failure was either inadequate decompression or misdiagnosis.

Hypothyroidism presenting as muscle stiffness and pseudohypertrophy: Hoffmann's syndrome

There is a spectrum of muscular abnormalities that occurs in patients with hypothyroidism. Alterations in deep tendon reflexes are commonly observed although more extensive muscle disease is less frequently seen. Two patients who demonstrated increased muscle mass, muscle stiffness with variable degrees of muscle weakness and low levels of serum thyroxine (Hoffmann's syndrome) are described. At the time of presentation, the serum creatinine phosphokinase level was more than 10 times greater than normal, and electromyography revealed repetitive positive waves. After therapy with thyroid hormone, there was complete resolution of the muscle abnormalities, and laboratory studies were performed. In this report, we review the clinical syndrome of muscle dysfunction that can be seen with the more severe forms of hypothyroid myopathy.

The treatment of tension headache—I. Muscular abnormality and biofeedback

The specificity and efficacy of a short EMG biofeedback treatment were assessed in a selected group of chronic tension-headache cases—those having significantly elevated levels of muscle tension. The effects of training patients to raise/maintain EMG levels were compared to those obtained from patients who were trained to lower tension levels. The results showed little evidence of increased self-control of the muscle despite successful EMG control during six bio-feedback sessions. A progressive and significant reduction in resting level was found only in the groups trained to reduce EMG levels. The treatment proved ineffectual in reducing headache. The implications of the dissociation of muscle tension and headache are discussed both with respect to current views of tension headaches and the role of biofeedback in their treatment.

The treatment of tension headache—II. EMG ‘normality’ and relaxation

A selected group of patients complaining of severe and chronic tension headache (without muscular abnormality) were given a short 3-week course of relaxation treatment. Half of the subjects received progressive relaxation instructions, while the other half received relaxation plus calming imagery. Both groups showed substantial improvements in pain behaviour and in pain experience. The improvements were synchronous and still present at the 6–8 week follow-up assessment. Although no significant differences were found between the groups, the addition of imagery appeared to produce larger improvements on a number of measures. These results were compared with those reported obtained in a previous biofeedback study and the implications of both the studies were discussed with respect to tension headache and its treatment.

Muscular and other abnormalities in a case of Edwards' Syndrome (18‐trisomy)

This paper describes the anatomical variations observed in a specimen exhibiting Edwards' Syndrome (18-trisomy). The clinical and autopsy data are compared with those reported in earlier literature. Aside from having a tracheoesophageal fistula, the viscera were characterized by abnormalities of the heart, lungs, liver and kidneys. The facial musculature was relatively undifferentiated. Only a few abnormalities were recorded in the otomandibular and suprahyoid structures. The infrahyoid region had three pairs of supernumerary muscles, including the "sternohyoideus azygos." The bluk of abnormalities were found in the muscles and nerves of the upper limb. These included the absence of the palmaris longus and brevis, the subclavius and the extensor digiti quinti proprius; the presence of supernumerary muscles, e.g., the "rhomboideus occipitalis," the "latissimocondyloideus," and the "subclavius posticus." The deltoid and the pectoralis major were fused to form the "deltopectoral" complex. A definitive musculocutaneous nerve was found in the right arm only. In the lower extremity supernumerary muscles included the "tenuissimus," "peroneus quinti digiti," and the "extensor primi internodii hallucis."

HISTOMETRIC AND ELECTRON CYTOCHEMICAL STUDY OF MUSCLE IN THE DYSTROPHIC MOUSE *

A histometric analysis of the alterations at the motor end plate in dystrophic Bar Harbor mice has been performed. In both forms of mouse dystrophy, simplification and focal atrophy of the junctional folds and retraction of the nerve terminal represented the significant changes. The postsynaptic alterations were similar to those described in Duchenne dystrophy. In constrast, the presence of presynaptic alterations in these mice indicated the presence of both a neural and a muscular abnormality. The wedge-shaped focal lesions in the muscle of dystrophic mice were demonstrated by both in vitro and in vivo HRP tracer techniques. These focal degenerative changes in muscle were similar to those described in Duchenne dystrophy. Employing the technique of extracellular space tracing, a comparison was made of the appearance of the transverse tubular system in the various types of dystrophic muscle fibers.