Muscle Disorders

Introduction

Muscle Disorders are the diseases and disorders that affect the human muscle system and their main manifestation is skeletal muscle weakness. The terms ‘muscular dystrophy’, ‘neuromuscular conditions’ and ‘neuromuscular disorders’ fall under the umbrella of the term 'Muscle Disorders'. These disorders are a large group of conditions which affect either the muscles, such as those in the arms and legs or heart and lungs, or the nerves which control the muscles[1]. Disorders of muscle may cause weakness or paralysis in the presence of an intact nervous system. 

Classification

Muscle disorders can be classified on the basis of :

  1. Primary or secondary : Diseases and disorders as a result of direct abnormalities of the muscles are considered primary muscle diseases, Eg. Polymyositis. And Diseases that are secondary to another condition and may have caused muscle damage, Eg. diseases due to endocrine issues .
  2. Genetic or Acquired
  3. Neuromuscular or Myopathies

Etiology

Causes of muscle disorders include[1]:

  • Age, hereditary
  • Injury or overuse, such as sprains or strains, cramps or tendinitis
  • A genetic disorder, such as muscular dystrophy
  • Some cancers
  • Inflammation, such as myositis
  • Diseases of nerves that affect muscle
  • Infectious Diseases
  • Certain medicines
  • Metabolic causes and Endocrine causes
  • Autoimmune disorders
  • Etiology may not be known at times

Symptoms

Symptoms vary with the different types of muscular disorder.

Symptoms may include:

  1. Muscle weakness that slowly gets worse.
  2. breathing issues, especially dyspnea (shortness of breath)
  3. dizziness,
  4. Fatigue
  5. Muscle wasting, loss of strength
  6. high fever,
  7. a stiff neck. 
  8. Numbness, tingling, or painful sensations
  9. Double vision
  10. Droopy eyelids
  11. Problems with swallowing—dysphagia
  12. Difficulty using one or more muscle groups, muscle weakness,
  13. Problems walking, balance and frequent falls[2]

Types Of Muscle Disorders

Common types of Muscle Disorders include

  1. Myopathies eg Polymyositis, Dermatomyositis, Duchenne Muscular Dystrophy, Steroid induced myopathy
  2. Cramp: prolong painful involuntary contraction of skeletal muscles
  3. Fibrositis: Inflammation of fibrous connective tissues in muscles.it also effect muscles of trunk and back.[3]
  4. Myasthenia Gravis
  5. Rhabdomyolysis
  6. Cardiac Myopathy: Coronary Artery Disease
  7. Amyotrophic Lateral Sclerosis
  8. Sarcopenia: This muscle disease can be primary or secondary. Sarcopenia causes muscle mass loss and muscle strength loss.

Diagnosis

Usually it is first suspected because of symptoms: a muscle weakness is noticed by the patient, family or a doctor.[4]

Muscle Disorders may be diagnosed using one or more of the following tests:

  1. An electromyography (EMG) - this is a recording of the electrical activity in a muscle. It can diagnose muscle disorders, nerve and motor problems, and degenerative diseases.
  2. A blood test : measuring specific muscle enzymes and antibodies that may be specific to one disorder or many
  3. A muscle biopsy - this involves taking a small sample of muscle under local anaesthetic. The sample is examined under the microscope and the muscle chemicals (proteins) may be tested.
  4. Genetic analysis - this involves testing a person's DNA using a blood sample. It can detect many (not all) cases of MD.
  5. MRI: to show abnormal muscle areas
  6. Muscle ultrasound is used to look for suspected CMD.

Treatment

There is currently no cure for muscular disorders, but a variety of treatments can help manage the condition.[5] The goals of treatment for muscle diseases may include:

  1. treating symptoms,
  2. delaying disease progression, and
  3. improving quality of life.

Medical Management

Corticosteroids taken by mouth are sometimes prescribed for reducing cramping and spasms. Immunosuppressants—drugs inhibit or prevent the overactivity of the immune system—may be given for some muscle and nerve diseases, and conditions that affect both the nerves and muscles.

  • Surgical corrections may be advised if needed.
  • The person should be as active as possible. Complete inactivity (such as bedrest) can make the disease worse.[6]

Physiotherapy Management

The physical therapist is part of multidisciplinary team and management of such disorders is long-term.

The Physical therapy goals may include:

Reference

  1. 1.0 1.1 A service of the U.S. National Library of Medicine. From the National Institutes of HealthNational Institutes of Health http://www.nlm.nih.gov/medlineplus/muscledisorders.html
  2. Sarnat HB. Muscular dystrophies. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics . 19th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 601.
  3. ivyrose holistic http://www.ivy-rose.co.uk/HumanBody/Muscles/Muscular_Disorders.php
  4. Individual & Caretaker Workbook Simple and Easy Instructionshttp://myhealth.patient.co.uk/
  5. http://www.nhs.uk/Conditions/Muscular-dystrophy/Pages/Treatment.aspx
  6. Bushby RF, Birnkrant DJ, Case LE, Clemens PR, Cripe L, Kaul A, et al. Diagnosis and management of Duchenne muscular dystrophy. Lancet Neurol . 2010;9:77-93. http://www.nytimes.com/health/guides/disease/muscular-dystrophy/overview.html