This experiment was designed to explore the correlation between the mechanism of immobilization-induced skeletal muscle atrophy and the apoptosis of muscular cells. The models of skeletal muscle atrophy induced by immobilization for different length of time were established according to Sievanen II methods. 24 rabbits, each of them having one hind leg fixed by the tubal plaster and the other one free as control, were randomly divided into four groups depending on time of fixation (3, 7, 14, and 28 days respectively). The animals were sacrificed by the end of fixation. TdT-mediated d-UTP nick end labeling (TUNEL) was used to investigate the apoptotic muscle cells in the animal's bone. By comparing the apoptotic muscle cells with the morphology of the skeletal muscle, the correlation between cell apoptosis and skeletal muscle atrophy were analyzed. Apoptotic muscle cells did appear after immobilization in the atrophied skeletal muscle. In various groups, some cells with false positive stained TUNEL were found in the atrophic muscle, which could be distinguished from apoptotic cells by their characteristics. In conclusion, cell apoptosis participates in the process of skeletal muscle atrophy induced by immobilization; the amount of apoptotic cells is strongly associated with the time of immobilization, its peak appears on the 14th day of immobilization; the distribution of apoptotic skeletal muscle cell varies with the time of fixation. The severity of skeletal muscle atrophy is associated with the degree of the muscle cell apoptosis.
Animals ; Apoptosis ; physiology ; Immobilization ; In Situ Nick-End Labeling ; Muscle, Skeletal ; pathology ; Muscular Atrophy ; etiology ; Rabbits

Angiotensin II ; metabolism ; Animals ; Male ; Muscle, Skeletal ; Muscular Atrophy ; etiology ; metabolism ; pathology ; Rats ; Rats, Sprague-Dawley

Bilateral suprascapular nerve entrapment syndrome is very rare. It presents with shoulder pain, weakness and atrophy of the supraspinatus and infraspinatus muscles. We present a twenty-year old man having a history of bilateral shoulder pain associated with weakness. Electromyographic studies revealed signs of a lesion that caused a neupraxic state of the left suprascapular nerve, moderate axonal loss of the right suprascapular nerve and denervation of the right suprascapular muscle. The patient was treated with physical and medical therapy. Due to worsening of the symptoms, a surgical operation was performed by the excision of the transverse scapular ligaments bilaterally. His pain, weakness and atrophy had diminished on examination six weeks later. Suprascapular nerve entrapment should be considered in patients with shoulder pain, particularly those with weakness and atrophy of the supraspinatus and infraspinatus muscles.
Adult ; *Back ; Human ; Magnetic Resonance Imaging ; Male ; Muscle Weakness/etiology/*pathology ; Muscular Atrophy/etiology/*pathology ; Nerve Compression Syndromes/complications/*pathology ; Pain/etiology/pathology ; *Shoulder

OBJECTIVESTo compare the paravertebral muscle (such as multifidus, erector spinae, psoas muscle) changes between the patients with degenerative lumbar instability and normal person by MRI and to observe the degeneration of paravertebral muscles. To analyze the relationship between paravertebral muscle degeneration and lumbar curvature of degenerative lumbar instability.

METHODSSixty patients with degenerative lumbar instability were retrospectively enrolled from December 2011 to July 2013 as degeneration group, meanwhile 60 health persons with no degenerative lumbar instability were selected as control group. No significant differences were found in the gender, age and body mass index between the two groups. The cross-sectional area(CSA) and percentage of fat infiltration area (FIA) of the paravertebral muscles at the L4-S1 levels were measured using T2-weighted axial MRI and Image J soft ware. And the lumbar curvature(expressed as lumbar lordosis angle) of all the patients in lumbar X-ray were measured in the two groups. The measured data were analyzed with independent samples t-test.

RESULTSThe difference of multifidus cross-sectional area and the percentage of fat infiltration in the patients of degenerative lumbar instability at the L4-L5, L5-S1 level, compared with the control group, was statistically significant (t = 2.768, t = 6.216, P < 0.05). Between the two groups, the percentage of fatty infiltration in erector spinae showed significant differences (t = 5.862, P < 0.05). The cross-sectional area of erector spinae and the degeneration of the psoas muscle between the two groups was not statistically significant. The lumbar lordsis angle in the patients with degenerative lumbar instability was (43.9 ± 15.6)°, which was higher than the (39.3 ± 14.2)° in control group (t = 2.915, P < 0.05).

CONCLUSIONSCompared with the control group, patients with degenerative lumbar instability exists erector spinae and multifidus muscle degeneration, and erector spinae is more obvious. The degeneration among psoas muscle, erector spinae and multifidus muscle are inconsistent, which may be related to the increasing of the lumbar lordosis angle in the patients with degenerative lumbar instability.

Aged ; Case-Control Studies ; Female ; Humans ; Joint Instability ; diagnosis ; etiology ; pathology ; Lumbosacral Region ; physiopathology ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Muscle, Skeletal ; pathology ; Muscular Atrophy ; complications ; diagnosis ; pathology

Spinal and bulbar muscular atrophy (SBMA) is a rare X-linked motor neuron disease with significant phenotypic viability. Here, we present a genetically identified SBMA family without bulbar paralysis or androgen insensitivity. All four male patients presented with progressive lower motor neuron paralysis in all limbs, with distal extremities more dominant. None of them had bulbar palsy or androgen insensitivity. A consistently mild elevated blood creatine phosphokinase (CPK) levels were detected in all patients and the EMG showed a chronic neurogenic damage. Muscle biopsy of propositus indicated a typical neurogenic amyotrophy. Genetic testing for SMA of mutation in SMN1 was negative, while for SBMA of androgen receptor showed the increased CAG repeat in exon 1, suggesting that although bulbar symptoms and androgen insensitivity are characteristic symptoms of SBMA, they are not obligatory for the diagnosis. In adult males with a chronic motor neuron syndrome without upper motor neuron signs, even in absence of the classical features of androgen insensitivity or bulbar findings, genetic testing for SBMA should be strongly considered.
Adult ; Bulbo-Spinal Atrophy, X-Linked ; complications ; diagnosis ; genetics ; Creatine Kinase ; blood ; Genetic Testing ; Humans ; Male ; Motor Neurons ; pathology ; Muscular Atrophy ; etiology ; Mutation ; genetics ; Paralysis ; diagnosis ; etiology ; Pedigree ; Receptors, Androgen ; genetics

In this study, we compared the paramedian interfascial approach (PIA) and the traditional midline approach (MA) for lumbar fusion to determine which approach resulted in the least amount of postoperative back muscle atrophy. We performed unilateral transforaminal posterior lumbar interbody fusion via MA on the symptomatic side and pedicle screw fixation via PIA on the other side in the same patient. We evaluated the damage to the paraspinal muscle after MA and PIA by measuring the preoperative and postoperative paraspinal muscle volume in 26 patients. The preoperative and postoperative cross-sectional area, thickness, and width of the multifidus muscle were measured by computed tomography. The degree of postoperative paraspinal muscle atrophy was significantly greater on the MA side than on the contralateral PIA side (-20.7% and -4.8%, respectively, p<0.01). In conclusion, the PIA for lumbar fusion yielded successful outcomes for the preservation of paraspinal muscle in these 26 patients. We suggest that the success of PIA is due to less manipulation and retraction of the paraspinal muscle and further studies on this technique may help confirm whether less muscle injury has positive effects on the long-term clinical outcome.
Adult ; Aged ; *Bone Screws ; Female ; Humans ; Lumbar Vertebrae/*surgery ; Male ; Middle Aged ; Muscle, Skeletal/pathology ; Muscular Atrophy/etiology/pathology ; Postoperative Complications/etiology/pathology ; Reproducibility of Results ; Retrospective Studies ; Spinal Fusion/adverse effects/instrumentation/*methods ; Tomography, X-Ray Computed

To study the effects of ciliary neurotrophic factor (CNTF) on denervated skeletal muscle atrophy and to find a new approach to ameliorate atrophy of denervated muscle, a model was established by cutting the right sciatic nerve in 36 Wistar mice, with the left side serving as control. Then they were divided into two groups randomly. CNTF (1 U/ml) 0.1 ml was injected into the right tibial muscle every day in experimental group, and saline was used into another group for comparison. The muscle wet weight, muscle total protein, Ca2+, physiological response and morphology were analyzed on the 7th, 14th and 28th day after operation. Our results showed that compared to control group, there was a significant increase in muscle wet weight, total protein, Ca2+, muscle fiber cross-section area in CNTF group (P < 0.05). CNTF could ameliorate the decrease of tetanic tension (PO), post-tetanic twitch potentiation (PTP), and the prolonged muscle relaxation time (RT) caused by denervation (P < 0.05). The motor end-plate areas 7 days and 14 days after denervation was similar (P > 0.05), but significantly larger 28 days after the denervation (P < 0.05). Our results suggest that CNTF exerts myotrophic effects by attenuating the morphological and functional changes associated with denervation of rat muscles and has protective effects on denervated muscle and motor end plate.
Animals ; Ciliary Neurotrophic Factor ; pharmacology ; Male ; Motor Endplate ; pathology ; physiopathology ; Muscle Denervation ; adverse effects ; Muscle, Skeletal ; innervation ; pathology ; physiopathology ; Muscular Atrophy ; etiology ; prevention & control ; Random Allocation ; Rats ; Rats, Wistar ; Sciatic Nerve ; surgery

PURPOSE: The purpose of this study was to examine the effects of cerebral ischemia on Type I(soleus) and Type II(plantaris, gastrocnemius) muscles, and to determine the effects of isometric contraction training by electrostimulation on Type I andII muscles in cerebral ischemia model rats. METHOD: Twenty-five male Sprague-Dawley rats were randomly divided into four groups: ST(stroke), STES(stroke+electrostimulation), SH(sham) and SHES (sham+electrostimulation). The ST and STES groups received a transient right middle cerebral artery occlusion operation. The SH and SHES groups received a sham operation. The STES and SHES groups had daily isometric contraction training by electrostimulation(100Hz, 45mA, 7.5V) on hindlimb muscles for 7days. RESULT: Plantaris and gastrocenmius muscle weight, myofibrillar protein contents of soleus and gastrocnemius, and the muscle fiber cross-sectional area of gastrocnemius in the ST group significantly decreased compared with the SH group. Soleus, plantaris, gastrocnemius muscle weight, myofibrillar protein contents of soleus and gastrocnemius, and the Type I muscle fiber cross-sectional area of soleus and the Type II muscle fiber cross-sectional area of gastrocnemius in the STES group significantly increased compared with the ST group. CONCLUSION: Hindlimb muscle atrophy occurs after acute stroke and isometric contraction training by electrostimulation during early stages of a stroke attenuates muscle atrophy of Type I and Type II muscles.
Animals ; Body Weight ; Brain Ischemia/*complications ; Disease Models, Animal ; Electric Stimulation ; Hindlimb ; *Isometric Contraction ; Male ; Muscle Proteins/analysis ; Muscle, Skeletal/metabolism/pathology/*physiopathology ; Muscular Atrophy/*etiology/pathology/physiopathology ; Myofibrils/chemistry ; Rats ; Rats, Sprague-Dawley ; Stroke/*complications

PURPOSE: The purpose of this study was to examine the effect of DHEA (Dehydroepiandrosterone) on muscle weight and Type I and II fiber cross-sectional area of affected and unaffected hindlimb muscles in rats with neuropathic pain induced by unilateral peripheral nerve injury. METHODS: Neuropathic pain was induced by ligation and cutting of the left L5 spinal nerve. Adult male Sprague-Dawley rats were randomly assigned to one of two groups: The DHEA group (n=10) had DHEA injections daily for 14 days, and the Vehicle group (n=10) had vehicle injections daily for 14 days. Withdrawal threshold, body weight, food intake and activity were measured every day. At 15 days all rats were anesthetized and soleus, plantaris and gastrocnemius muscles were dissected from the both hindlimbs. Body weight, food intake, activity, muscle weight and Type I, II fiber cross-sectional area of the dissected muscles were measured. RESULTS: The DHEA group showed significant increases (p<.05), as compared to the vehicle group for muscle weight of the unaffected plantaris, and in Type II fiber cross-sectional area of the gastrocnemius muscle. The DHEA group demonstrated a higher pain threshold than the vehicle group whereas total diet intake and activity score were not significantly different between the two groups. CONCLUSION: DHEA administration for 14 days attenuates unaffected plantaris and gastrocnemius muscle atrophy.
Animals ; Body Weight ; Dehydroepiandrosterone/*administration & dosage ; Disease Models, Animal ; Eating/drug effects ; *Hindlimb ; Male ; Muscle Fibers, Skeletal/*drug effects/pathology ; Muscle, Skeletal/drug effects ; Muscular Atrophy/*drug therapy ; Pain/etiology ; Pain Measurement ; Peripheral Nerves/*injuries ; Rats ; Rats, Sprague-Dawley

PURPOSE: The purpose of this study was to identify muscle atrophy in critically ill patients on ventilators. A comparison was made between limb circumferences and muscle areas on the day of admission to an intensive care unit (ICU) and on the 8th day after admission. METHODS: The data were collected from 30 critically ill patients using ventilators at S hospital ICU in Seoul during the period from October 2005 to April 2006. Limb circumferences and skinfold thickness were measured on the day of admission and on the 8th day after admission to the ICU. Limb circumferences and skinfold thickness were measured on the right mid-arm, right mid-thigh, and right mid-calf using a measuring tape and a skinfold calipers. Limb muscle areas were calculated by an equation after measuring limb circumferences and skinfold thickness. The data were analyzed by paired t-test and independent t-test. RESULTS: 1) Mid-arm circumference, mid-thigh circumference and mid-calf circumference on the 8th day after admission to the ICU were significantly less than those on the day of admission to the ICU, 2) Mid-arm muscle area, mid-thigh muscle area and mid-calf muscle area on the 8th day after admission to the ICU were significantly less than those on the day of admission to the ICU, 3) Steroid and vecuronium medication didn't affect changes in limb circumferences (mid-arm, mid-thigh, mid-calf) and muscle areas (mid-arm, mid-thigh, mid-calf) on the 8th day after admission to the ICU compared to the day of admission. CONCLUSION: Limb muscle atrophy may occur on the 8th day after admission to the ICU in critically ill patients using ventilator.
Adult ; Aged ; Critical Illness ; Data Interpretation, Statistical ; Extremities/physiology ; Female ; Humans ; Intensive Care Units ; Male ; Middle Aged ; Muscle, Skeletal/pathology ; Muscular Atrophy/*diagnosis/etiology/therapy ; Skinfold Thickness ; Steroids/administration & dosage ; *Ventilators, Mechanical