Muscle weakness

For patient information, click here

Muscle weakness
Muscle wasting in HIV. Image courtesy of Professor Peter Anderson DVM PhD and published with permission © PEIR, University of Alabama at Birmingham, Department of Pathology

WikiDoc Resources for Muscle weakness
Articles
Most recent articles on Muscle weakness Most cited articles on Muscle weakness Review articles on Muscle weakness Articles on Muscle weakness in N Eng J Med, Lancet, BMJ
Media
Powerpoint slides on Muscle weakness Images of Muscle weakness Photos of Muscle weakness Podcasts & MP3s on Muscle weakness Videos on Muscle weakness
Evidence Based Medicine
Cochrane Collaboration on Muscle weakness Bandolier on Muscle weakness TRIP on Muscle weakness
Clinical Trials
Ongoing Trials on Muscle weakness at Clinical Trials.gov Trial results on Muscle weakness Clinical Trials on Muscle weakness at Google
Guidelines / Policies / Govt
US National Guidelines Clearinghouse on Muscle weakness NICE Guidance on Muscle weakness NHS PRODIGY Guidance FDA on Muscle weakness CDC on Muscle weakness
Books
Books on Muscle weakness
News
Muscle weakness in the news Be alerted to news on Muscle weakness News trends on Muscle weakness
Commentary
Blogs on Muscle weakness
Definitions
Definitions of Muscle weakness
Patient Resources / Community
Patient resources on Muscle weakness Discussion groups on Muscle weakness Patient Handouts on Muscle weakness Directions to Hospitals Treating Muscle weakness Risk calculators and risk factors for Muscle weakness
Healthcare Provider Resources
Symptoms of Muscle weakness Causes & Risk Factors for Muscle weakness Diagnostic studies for Muscle weakness Treatment of Muscle weakness
Continuing Medical Education (CME)
CME Programs on Muscle weakness
International
Muscle weakness en Espanol Muscle weakness en Francais
Business
Muscle weakness in the Marketplace Patents on Muscle weakness
Experimental / Informatics
List of terms related to Muscle weakness

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-In-Chief: M.Umer Tariq [2]

Overview

Muscle weakness (or "lack of strength") is a direct term for the inability to exert force with ones muscles to the degree that would be expected given the individual's general physical fitness. A test of strength is often used during a diagnosis of a muscular disorder before the etiology can be identified. Such etiology depends on the type of muscle weakness, which can be true or perceived as well as variable topically. True weakness is substantial, while perceived rather is a sensation of having to put more effort to do the same task. On the other hand, various topic locations for muscle weakness are central, neural and peripheral. Central muscle weakness is an overall exhaustion of the whole body, while peripheral weakness is an exhaustion of individual muscles. Neural weakness are somewhere between.

Muscle weakness can be a result of vigorous exercise but abnormal fatigue may be caused by barriers to or interference with the different stages of muscle contraction.

In a broader sense, muscle weakness is the physical part of fatigue (medical).

Classification

True vs. Perceived

The term subsumes two other more specific terms, true weakness and perceived weakness.

• True weakness (or "objective weakness") describes a condition where the instantaneous force exerted by the muscles is less than would be expected. For instance, if a patient suffers from amyotrophic lateral sclerosis (ALS), motor neurons are damaged and can no longer stimulate the muscles to exert normal force.

• Perceived weakness (or "subjective weakness") describes a condition where it seems to the patient that more effort than normal is required to exert a given amount of force. For instance, in some people with chronic fatigue syndrome (CFS) who may struggle to climb a set of stairs when feeling especially fatigued, their muscle strength when objectively measured (eg, the maximum weight they can press with their legs) is essentially normal, though this is not true for CFS patients who may be disabled through post-exertional weakness/malaise etc. and in severe cases may not be able to climb a flight of stairs.

In some conditions, such as myasthenia gravis muscle strength is normal when resting, but true weakness occurs after the muscle has been subjected to exercise. This is also true for some cases of CFS, where objective post-exertion muscle weakness with delayed recovery time has been measured and is a feature of some of the published definitions.

In addition to true/perceived, muscle weaknes can also be central, neural and peripheral. Central muscle weakness manifests as an overall, bodily or systemic, sense of energy deprivation, and peripheral weakness manifests as a local, muscle-specific incapacity to do work. Neural weakness can be both central and peripheral.

Complete Differential Diagnosis of Causes of Muscle weakness

(In alphabetical order)

3-Methylglutaconic aciduria 3-Quinuclidinyl benzilate Acamprosate Accessory nerve disorder Acitretin Acute intermittent porphyria Acute peripheral neuropathy Acute viral nasopharyngitis (common cold) Addison's disease Adrenal carcinoma Alcoholic polyneuropathy Aluminum Hydroxide Amiloride and Hydrochlorothiazide Amiodarone Oral Amyotrophic lateral sclerosis Anorexia nervosa Arnold-Chiari malformation Arthrogryposis Autism Bassen-Kornzweig syndrome Becker's muscular dystrophy Beclomethasone Oral Inhalation Benztropine Mesylate Oral Bezafibrate Botulism Brachial plexus injury Brompheniramine Budesonide Inhalation Powder Bulimia nervosa Cadmium poisoning Carnitine palmitoyltransferase I deficiency Chloroquine Phosphate Oral Chlorothiazide Chlorpheniramine Chlorthalidone Chronic fatigue syndrome Chronic inflammatory demyelinating polyneuropathy Ciclesonide Nasal Spray Cirrhosis Clofibrate Colistimethate Injection Congenital muscular dystrophy Congenital myasthenic syndrome Congenital myopathy Connective tissue disease Cushing's syndrome Cyanocobalamin Injection Cyproheptadine Cytarabine Daptomycin Decompression sickness Dejerine Sottas syndrome Dermatomyositis Desipramine Devic's disease Dexamethasone Oral Dextroamphetamine and Amphetamine Diabetic amyotrophy Diabetic neuropathy Dicamba Dicyclomine Diphenhydramine Oral Donepezil Dorzolamide and Timolol Ophthalmic Doxazosin Doxylamine Duchenne muscular dystrophy Emery-Dreifuss Muscular Dystrophy Engelmann syndrome Epidural hematoma Exercise intolerance Ezetimibe Facioscapulohumeral muscular dystrophy Fexofenadine and Pseudoephedrine Fludrocortisone Acetate Flunisolide Nasal Inhalation Fluoride poisoning Fluticasone and Salmeterol Oral Inhalation Fluvastatin Frailty syndrome Friedreich's ataxia Galantamine Gemeprost Glucocorticoids Glutaric aciduria type 1 Glycogen storage disease type II GM1 gangliosidoses Graves' Disease Group A streptococcal infection Guanidinoacetate methyltransferase deficiency Guillain-Barre syndrome Hereditary inclusion body myopathy Hereditary spastic paraplegia Herpes zoster Hexane-2,5-dione HIV Hopkins syndrome Hydrochlorothiazide Hydrocortisone Injection Hydrocortisone Oral Hydroxychloroquine Hydroxyzine Hyperaldosteronism Hypercalcemia Hyperkalaemic periodic paralysis

Hyperkalemia Hypermagnesemia Hypermethioninemia Hyperpituitarism Hyperthyroidism Hypoglycemia Hypokalemic periodic paralysis Hypomagnesemia Hypophosphatemia Hypothyroidism Imiquimod Inclusion body myositis Influenza Interferon Beta-1b Injection Juvenile dermatomyositis Juvenile primary lateral sclerosis Kennedy disease Krabbe disease Lambert-Eaton myasthenic syndrome Leflunomide Letrozole Levalbuterol Oral Inhalation Limb-girdle muscular dystrophy Lisinopril and Hydrochlorothiazide Lithium Loprazolam Lormetazepam Lovastatin Low-carbohydrate diet Machado-Joseph disease Marinesco-Sjogren syndrome Mepyramine Metabolic acidosis Metachromatic leukodystrophy Methyclothiazide Methyldopa and Hydrochlorothiazide Methylprednisolone Oral Metolazone Mitochondrial trifunctional protein deficiency Motor neurone disease Multiple sclerosis Myasthenia gravis Nelson's syndrome Nemaline myopathy Nitrazepam Nitrofurantoin Oxcarbazepine Peripheral Arterial Disease Peripheral neuropathy Phosphofructokinase deficiency Poliomyelitis Polymyositis Postherpetic neuralgia Post-polio syndrome Pott's disease Pramipexole Pravastatin Prazosin and polythiazide Prednisone Primary carnitine deficiency Primary hyperparathyroidism Primary lateral sclerosis Procyclidine Pseudoephedrine and triprolidine Pyridostigmine Pyruvate carboxylase deficiency Reserpine, hydralazine, and hydrochlorothiazide Rhabdomyolysis Rhabdomyolysis Rheumatoid Arthritis Rhinovirus Riluzole Rosuvastatin Salmeterol oral inhalation Sandhoff disease Schilder's disease Scleroderma Selegiline Sjogren's Syndrome Small fiber peripheral neuropathy Somatization disorder Spinal cord injury Spinal disc herniation Spinal stenosis Spironolactone Spondylosis Sturge-Weber syndrome Tabes dorsalis Tamoxifen Telbivudine Temik Tension myositis syndrome Teriparatide (rDNA origin) Injection Thyrotoxicosis Tocopherol Topiramate Trastuzumab Triamcinolone Nasal Inhalation Triamterene Trimeprazine Uremia Variegate porphyria Vitamin D deficiency Walker-Warburg syndrome Zoledronic Acid Injection

Complete Differential Diagnosis of the Causes of Muscle weakness

(By organ system)

Cardiovascular	Peripheral Arterial Disease,
Chemical / poisoning	Cadmium poisoning, Dicamba, Fluoride poisoning, Hexane-2,5-dione, Temik,
Dermatologic	No underlying causes
Drug Side Effect	3-Quinuclidinyl benzilate, Acamprosate (patient information), Acitretin (patient information), Aluminum Hydroxide (patient information), Amiloride and Hydrochlorothiazide (patient information), Amiodarone Oral (patient information), Beclomethasone Oral Inhalation (patient information), Benztropine Mesylate Oral (patient information), Bezafibrate (patient information), Brompheniramine (patient information), Budesonide Inhalation Powder (patient information), Chloroquine Phosphate Oral (patient information), Chlorothiazide (patient information), Chlorpheniramine (patient information), Chlorthalidone (patient information), Ciclesonide Nasal Spray (patient information), Clofibrate (patient information), Colistimethate Injection (patient information), Cyanocobalamin Injection (patient information), Cyproheptadine (patient information), Cytarabine (patient information), Daptomycin, Desipramine (patient information), Dexamethasone Oral (patient information), Dextroamphetamine and Amphetamine (patient information), Dicyclomine (patient information), Diphenhydramine Oral (patient information), Donepezil (patient information), Dorzolamide and Timolol Ophthalmic (patient information), Doxazosin (patient information), Doxylamine (patient information), Ezetimibe (patient information), Fexofenadine and Pseudoephedrine (patient information), Fludrocortisone Acetate (patient information), Flunisolide Nasal Inhalation (patient information), Fluticasone and Salmeterol Oral Inhalation (patient information), Fluvastatin (patient information), Galantamine (patient information), Gemeprost, Glucocorticoids, Hydrochlorothiazide (patient information), Hydrocortisone Injection (patient information), Hydrocortisone Oral (patient information), Hydroxychloroquine (patient information), Hydroxyzine (patient information), Imiquimod (patient information), Insulin lispro injection (patient information), Interferon Beta-1b Injection (patient information), Leflunomide (patient information), Letrozole (patient information), Levalbuterol Oral Inhalation (patient information), Lisinopril and Hydrochlorothiazide (patient information), Lithium (patient information), Loprazolam, Lormetazepam, Lovastatin (patient information), Mepyramine, Methyclothiazide (patient information), Methyldopa and Hydrochlorothiazide (patient information), Methylprednisolone Oral (patient information), Metolazone (patient information), Nitrazepam, Nitrofurantoin (patient information), Oxcarbazepine (patient information), Pramipexole (patient information), Pravastatin (patient information), Prazosin and polythiazide (patient information), Prednisone, Procyclidine (patient information), Pseudoephedrine and triprolidine (patient information), Pyridostigmine (patient information), Reserpine, hydralazine, and hydrochlorothiazide (patient information), Riluzole (patient information), Rosuvastatin (patient information), Salmeterol oral inhalation (patient information), Selegiline (patient information), Spironolactone (patient information), Tamoxifen (patient information), Telbivudine (patient information), Teriparatide (rDNA origin) Injection (patient information), Tocopherol, Topiramate, Trastuzumab (patient information), Triamcinolone Nasal Inhalation (patient information), Triamterene (patient information), Trimeprazine (patient information), Zoledronic Acid Injection (patient information),
Ear Nose Throat	Acute viral nasopharyngitis (common cold),
Endocrine	Addison's disease, Cushing's syndrome, Graves' Disease, Hyperaldosteronism, Hyperpituitarism, Hyperthyroidism, Hypothyroidism, Kennedy disease, Thyrotoxicosis,
Environmental	No underlying causes
Gastroenterologic	Cirrhosis,
Genetic	Bassen-Kornzweig syndrome, Becker's muscular dystrophy, Carnitine palmitoyltransferase I deficiency, Dejerine Sottas syndrome, Devic's disease, Engelmann syndrome, Glutaric aciduria type 1, Glycogen storage disease type II, GM1 gangliosidoses, Hereditary inclusion body myopathy, Hereditary spastic paraplegia, Metachromatic leukodystrophy, Nemaline myopathy, Phosphofructokinase deficiency, Primary carnitine deficiency, Pyruvate carboxylase deficiency, Sandhoff disease, Walker-Warburg syndrome,
Hematologic	Acute intermittent porphyria, Variegate porphyria,
Iatrogenic	No underlying causes
Infectious Disease	Botulism, Group A streptococcal infection, HIV, Influenza, Polymyositis, Pott's disease, Rhinovirus,
Musculoskeletal / Ortho	Arthrogryposis, Congenital muscular dystrophy, Congenital myasthenic syndrome, Congenital myopathy, Dermatomyositis, Diabetic amyotrophy, Duchenne muscular dystrophy, Emery-Dreifuss Muscular Dystrophy, Facioscapulohumeral muscular dystrophy, Inclusion body myositis, Rhabdomyolysis, Spondylosis,
Neurologic	Accessory nerve disorder, Acute peripheral neuropathy, Amyotrophic lateral sclerosis, Arnold-Chiari malformation, Chronic inflammatory demyelinating polyneuropathy, Diabetic neuropathy, Epidural hematoma, Friedreich's ataxia, Guillain-Barre syndrome, Juvenile primary lateral sclerosis, Machado-Joseph disease, Marinesco-Sjogren syndrome, Motor neurone disease, Multiple sclerosis, Myasthenia gravis, Peripheral neuropathy, Sturge-Weber syndrome, Tabes dorsalis,
Nutritional / Metabolic	3-Methylglutaconic aciduria, Guanidinoacetate methyltransferase deficiency, Metabolic acidosis, Vitamin D deficiency,
Obstetric/Gynecologic	No underlying causes
Oncologic	Adrenal carcinoma,
Opthalmologic	No underlying causes
Overdose / Toxicity	Benztropine Mesylate Oral (patient information), Fexofenadine and Pseudoephedrine (patient information), Galantamine (patient information), Salmeterol oral inhalation (patient information), Topiramate,
Psychiatric	Anorexia nervosa, Bulimia nervosa, Tension myositis syndrome,
Pulmonary	Hopkins syndrome,
Renal / Electrolyte	Hypercalcemia, Hyperkalaemic periodic paralysis, Hypermagnesemia, Hypermethioninemia, Hypokalemic periodic paralysis, Hypomagnesemia, Hypophosphatemia, Uremia,
Rheum / Immune / Allergy	Congenital myasthenic syndrome, Graves' Disease, Krabbe disease, Lambert-Eaton myasthenic syndrome, Rheumatoid Arthritis, Scleroderma, Sjogren's Syndrome,
Sexual	No underlying causes
Trauma	Brachial plexus injury,
Urologic	No underlying causes
Miscellaneous	Alcoholic polyneuropathy, Chronic fatigue syndrome, Mitochondrial trifunctional protein deficiency, Spinal cord injury, Spinal disc herniation, Spinal stenosis,

Differential Diagnosis

Acute/Sub Acute

• Acute peripheral neuropathy
• Corticosteroids
• Coxsackie
• Dermatomyositis
• Herpes zoster
• HIV
• Hypercalcemia
• Hyperkalemia
• Hypermagnesemia
• Hypoglycemia
• Hypokalemia
• Hypophosphatemia
• Influenza
• Liver Disease
• Organophosphates
• Poliomyelitis
• Polymyositis
• Rabies
• Rhabdomyolysis
• Thyrotoxicosis
• Uremia

Chronic Muscle Weakness

• Acromegaly
• Adrenocorticol insufficiency
• Alcoholic myopathy
• Amyotrophic lateral sclerosis
• Charcot-Marie-Tooth Disease
• Chronic fatigue syndrome
• Chronic infection
• Chronic peripheral neuropathy
• Cushing's Syndrome
• Depression
• Dermatomyositis
• Diabetic neuropathy
• Drugs/toxins
• Duchenne's muscular dystrophy
• Eaton-Lambert syndrome
• Facioscapulohumeral
• Glycogen Storage Disease
• Hypercalcemia
• Hyperkalemia
• Hyperthyroidism
• Hyperparathyroidism
• Hypoglycemia
• Hypokalemia
• Hypophosphatemia
• Hypothyroidism
• Inflammatory myopathy
• Lipid storage disease
• Liver Disease
• Lupus erythematosus
• Malignant tumor
• Malnutrition
• Mitochondrial myopathy
• Mitral Regurgitation
• Mitral Stenosis
• Mixed Connective Tissue Disease
• Multiple Sclerosis
• Myasthenia gravis
• Myotonic
• Oculopharyngeal
• Physical deconditioning
• Polymyositis
• Rhabdomyolysis
• Rheumatoid Arthritis
• Sjogren's Syndrome
• Somatization syndrome
• Steroid myopathy
• Uremia
• Vitamin D deficiency

Associated conditions

Muscle weakness may be due to problems with the nerve supply, neuromuscular disease such as myasthenia gravis) or problems with muscle itself. The latter category includes polymyositis and other muscle disorders

• Amyotrophic lateral sclerosis
• Botulism
• Centronuclear myopathy
• Myotubular myopathy
• Dysautonomia
• Charcot-Marie-Tooth disease
• Hypokalemia
• Motor neurone disease
• Muscular dystrophy
• Myasthenia Gravis
• Progressive muscular atrophy
• Spinal muscular atrophy
• Cerebral palsy
• Infectious mononucleosis
• Herpes Zoster
• Vitamin D deficiency
• Fibromyalgia
• Celiac Disease
• Hypercortisolism (Cushing's syndrome)
• Hypocortisolism (Addison's disease)
• Primary hyperaldosteronism (Conn's syndrome)
• Ehlers-Danlos syndrome

See also

• Asthenia
• Paresis
• Debility
• Malaise
• Cataplexy
• Hypotonia
• Muscle atrophy
• Mononucleosis
• Dystrophy

Diagnostic Findings

Image courtesy of Professor Peter Anderson DVM PhD and published with permission © PEIR, University of Alabama at Birmingham, Department of Pathology

• 

  Spinal cord ependymoma

References

Template:WikiDoc Sources