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  1. <Health Topics
    Bone, Joint, and Muscle Disorders
    Biology of the Musculoskeletal System
    • Introduction to the Biology of the Musculoskeletal System
    • Bones
    • Muscles
    • Tendons and Bursae
    • Ligaments
    • Joints
    • Effects of Aging on the Musculoskeletal System
    Symptoms of Musculoskeletal Disorders
    • Introduction to Symptoms of Musculoskeletal Disorders
    • Musculoskeletal Pain
      • Causes
      • Evaluation
        • Testing
      • Treatment
    • Difficulty Moving
      • Causes
        • Joint disorders
        • Weakness
      • Diagnosis
      • Treatment
    • Joint Stiffness
    • Joint Noises
    • Joint Pain: Single Joint
      • Causes
        • Common causes
        • Less common causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
      • Key Points
    • Joint Pain: Many Joints
      • Causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
      • Essentials for Older Adults
      • Key Points
    Diagnosis of Musculoskeletal Disorders
    • Medical History and Physical Examination in Musculoskeletal Disorders
      • Medical History
        • Pain
        • Stiffness
        • Fatigue
        • Joint instability
      • Physical Examination
      • Bones and joints
      • Muscles and nerves
    • Tests for Musculoskeletal Disorders
      • Laboratory Tests
      • Imaging Tests
        • X-rays
        • Bone scanning
        • Computed tomography (CT) and magnetic resonance imaging (MRI)
        • Dual-energy x-ray absorptiometry (DXA)
        • Ultrasonography
      • Other Diagnostic Procedures
        • Arthroscopy
        • Joint aspiration (arthrocentesis)
        • Nerve and muscle tests
    Systemic Rheumatic Diseases
    • Idiopathic Inflammatory Myopathies
      • Types
      • Symptoms
        • Muscle weakness
        • Joint aches and inflammation
        • Internal organ problems
        • Skin changes
      • Diagnosis
        • Blood tests
        • Electromyography and imaging tests
        • Biopsy
        • Other tests
      • Treatment
      • Prognosis
    • Eosinophilic Fasciitis
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
    • Mixed Connective Tissue Disease (MCTD)
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
    • Relapsing Polychondritis
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
    • Sjögren Syndrome
      • Symptoms
      • Diagnosis
        • Established criteria
        • Tear and saliva tests
        • Blood tests
      • Treatment
      • Prognosis
      • More Information
    • Overview of Systemic Rheumatic Diseases
      • Symptoms
      • Diagnosis
      • Treatment
    • Systemic Lupus Erythematosus (SLE)
      • Cutaneous lupus
      • Symptoms
        • Joint problems
        • Skin and mucous membrane problems
        • Lung problems
        • Heart problems
        • Lymph node and spleen problems
        • Nervous system problems
        • Kidney problems
        • Blood problems
        • Gastrointestinal tract problems
        • Pregnancy problems
      • Diagnosis
        • Laboratory tests
      • Treatment
        • Mild to moderate lupus
        • Severe lupus
        • Maintenance medications
        • Other medical conditions and pregnancy
      • Prognosis
      • More Information
    • Systemic Sclerosis
      • Symptoms
        • Skin changes
        • Joint changes
        • Gastrointestinal system changes
        • Lung and heart changes
        • Kidney changes
        • CREST syndrome
      • Diagnosis
      • Treatment
        • Skin and joint problems
        • Gastrointestinal problems
        • Lung and heart problems
        • Kidney problems
      • Prognosis
      • More Information
    Bone and Joint Infections
    • Artificial Joint Infectious Arthritis
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
      • Prevention
    • Osteomyelitis
      • Causes
        • Spread through the blood
        • Direct invasion
      • Spread from nearby structures
      • Symptoms
      • Diagnosis
      • Treatment
        • Antibiotics and antifungal medications
        • Surgery and drainage
      • Prognosis
      • More Information
    • Infectious Arthritis
      • Acute infectious arthritis
      • Chronic infectious arthritis
      • Causes
      • Acute infectious arthritis
      • Chronic infectious arthritis
      • Symptoms
        • Acute infectious arthritis
        • Chronic infectious arthritis
      • Diagnosis
      • Treatment
        • Antibiotics
        • Removal of pus
        • Splinting and physical therapy
      • Prognosis
      • More Information
    Foot and Ankle Problems
    • Achilles Tendinopathy
    • Sever Disease
      • Treatment
    • Achilles Tendon Bursitis
      • Symptoms
        • Posterior Achilles tendon bursitis
        • Anterior Achilles tendon bursitis
      • Diagnosis
      • Treatment
    • Achilles Tendon Enthesopathy
      • Diagnosis
      • Treatment
    • Bunion
      • Symptoms
      • Diagnosis
      • Treatment
    • Damage to Nerves in the Foot
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Freiberg Disease
      • Symptoms
      • Diagnosis
      • Treatment
    • Hammer Toe
      • Diagnosis
      • Treatment
    • Inferior Calcaneal Bursitis
    • Medial and Lateral Plantar Nerve Entrapment
      • Symptoms
      • Diagnosis
      • Treatment
    • Metatarsal Joint Pain
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Pain in the Ball of the Foot (Metatarsalgia)
    • Plantar Fasciitis
      • Symptoms
      • Diagnosis
      • Treatment
    • Plantar Fibromatosis
    • Sesamoiditis
      • Symptoms
      • Diagnosis
      • Treatment
    • Overview of Foot and Ankle Problems
      • Essentials for Older Adults: Foot Problems
      • Treatment
    • Tarsal Tunnel Syndrome
      • Symptoms
      • Diagnosis
      • Treatment
    • Tibialis Posterior Tendinosis and Tibialis Posterior Tenosynovitis
      • Symptoms
      • Diagnosis
      • Treatment
    Gout and Calcium Pyrophosphate Arthritis
    • Gout
      • Causes
      • Symptoms
      • Tophi
      • Complications of gout
      • Diagnosis
      • Treatment
        • Relieving acute flares of gout
        • Preventing further flares of gout
        • Lowering blood levels of uric acid
        • Mobilization flares
        • Other treatments
      • Prognosis
    • Calcium Pyrophosphate Deposition Disease
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
    • Basic Calcium Phosphate (BCP) Crystal Deposition Disease
      • Symptoms
      • Diagnosis
      • Treatment
    Hand Disorders
    • Boutonnière Deformity
      • Treatment
    • Carpal Tunnel Syndrome
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Cubital Tunnel Syndrome
      • Symptoms
      • Diagnosis
      • Treatment
    • De Quervain Syndrome
      • Symptoms
      • Diagnosis
      • Treatment
    • Dupuytren Contracture
      • Symptoms
      • Diagnosis
      • Treatment
    • Felon
      • Treatment
    • Hand Abscess
      • Treatment
    • Hand Infections Caused By Bites
      • Diagnosis
      • Treatment
    • Herpetic Whitlow
      • Treatment
    • Infection of the Tendon Sheath in the Fingers
      • Diagnosis
      • Treatment
    • Kienböck Disease
      • Symptoms
      • Diagnosis
      • Treatment
    • Osteoarthritis of the Hand
      • Diagnosis
      • Treatment
    • Radial Tunnel Syndrome
      • Treatment
    • Trigger Finger
      • Treatment
    • Overview of Hand Disorders
      • Hand and finger deformities
      • Hand and finger infections
      • Nerve compression syndromes of the hand
    • Ganglia
      • Symptoms
      • Diagnosis
      • Treatment
    • Swan-Neck Deformity
      • Treatment
    IgG4-Related Disease
    • IgG4-Related Disease
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
    Joint Disorders
    • Neuropathic Arthropathy
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
      • Prevention
    • Rheumatoid Arthritis (RA)
      • Symptoms
      • Diagnosis
        • Blood tests
      • Treatment
        • Medications
        • Lifestyle measures
        • Physical treatments
        • Surgery
      • Medications for Rheumatoid Arthritis
        • Disease-modifying antirheumatic drugs (DMARDs)
        • Other immunosuppressive agents
        • Nonsteroidal anti-inflammatory drugs (NSAIDs)
        • Corticosteroids
      • Prognosis
      • More Information
    • Overview of Spondyloarthritis
    • Ankylosing Spondylitis
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
      • More Information
    • Osteoarthritis (OA)
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
        • Physical measures
        • Medications
        • Surgery
        • Other treatments
      • More Information
    • Psoriatic Arthritis
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
      • More Information
    • Reactive Arthritis
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
      • More Information
    Low Back and Neck Pain
    • Herniated Disc
      • Symptoms
      • Diagnosis
      • Treatment
        • Measures to relieve pain
        • Surgery
      • Prevention
    • Sciatica
      • Symptoms
      • Diagnosis
      • Prevention
      • Treatment
        • Measures to relieve pain
        • Surgery
    • Lumbar Spinal Stenosis
      • Symptoms
      • Diagnosis
      • Treatment
        • Measures to relieve pain
        • Surgery
    • Spondylolisthesis
      • Symptoms
      • Diagnosis
      • Treatment
    • Cervical Spinal Stenosis
      • Symptoms
      • Diagnosis
      • Treatment
        • Measures to relieve pain
        • Surgery
    • Low Back Pain
      • Types of back pain
      • Causes
        • Common causes
        • Less common causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Prevention
      • Treatment
        • General measures for back pain
        • Treatment of chronic back pain
        • Surgery for back pain
        • Vertebral compression fractures
      • Key Points
    • Neck Pain
      • Causes
        • Common causes
        • Less common causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
        • General measures for neck pain
        • Other measures to reduce neck pain
        • Surgery for neck pain
      • Key Points
    Muscle, Bursa, and Tendon Disorders
    • Baker Cysts
      • Diagnosis
      • Treatment
    • Fibromyalgia
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
        • Improving sleep
        • Relieving pain
      • Prognosis
    • Introduction to Muscle, Bursa, and Tendon Disorders
    • Bursitis
      • Symptoms
      • Diagnosis
      • Treatment
    • Tendinitis and Tenosynovitis
      • Symptoms
      • Diagnosis
      • Treatment
      • Rotator Cuff Tendinitis
    Osteonecrosis
    • Osteonecrosis
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
        • Nonsurgical measures
        • Surgical procedures
      • Prevention
    Osteoporosis
    • Osteoporosis
      • Types of Osteoporosis
        • Primary osteoporosis
        • Secondary osteoporosis
        • Idiopathic osteoporosis
      • Symptoms
      • Diagnosis
        • Bone density testing
        • Other tests
      • Treatment
        • Calcium and vitamin D
        • Weight-bearing exercise
        • Medications
        • Treatment of pain and fractures
      • Prevention
      • More Information
    Paget Disease of Bone
    • Paget Disease of Bone
      • Causes
      • Symptoms
        • Complications
      • Diagnosis
      • Treatment
      • Prognosis
    Vasculitic Disorders
    • Behçet Disease
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
      • More Information
    • Overview of Vasculitis
      • Causes
      • Symptoms
      • Diagnosis
      • Prognosis
      • Treatment
        • Corticosteroids and other immunosuppressants
      • More Information
    • Polyarteritis Nodosa (PAN)
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
      • More Information
    • Giant Cell Arteritis
      • Symptoms
        • Headache and scalp pain
        • Blindness and visual disturbances
        • Jaw and tongue pain
        • Neurologic and cardiovascular problems
        • Polymyalgia rheumatica
      • Diagnosis
      • Treatment
      • More Information
    • Granulomatosis with Polyangiitis
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
      • More Information
    • Takayasu Arteritis
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
      • More Information
    • Eosinophilic Granulomatosis with Polyangiitis
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
      • More Information
    • Immunoglobulin A–Associated Vasculitis
      • Symptoms
      • Diagnosis
      • Treatment
      • More Information
    • Microscopic Polyangiitis
      • Symptoms
      • Diagnosis
      • Treatment
      • More Information
    • Polymyalgia Rheumatica
      • Symptoms
      • Diagnosis
      • Treatment
      • More Information
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