1. Ligament injury
    1. Anterior Cruciate Ligament Tear
    2. Posterior Cruciate Ligament Tear
  2. Meniscus Injury
    1. Medial Meniscus Injury
    2. Lateral Meniscus Injury
  3. Patella injury
    1. Patella subluxation
    2. Patella dislocation
  4. Intra-articular Fracture
  • Causes
  • Rheumatic Conditions
  1. Reiter's Syndrome
  2. Rheumatoid Arthritis
  3. Gout
  4. Pseudogout
  5. Osteoarthritis
  • Causes
  • Infectious Disease
  1. Gonorrhea
  2. Lyme Disease
  3. Tuberculosis
  4. Brucellosis
  • Causes
  • Malignant Tumor
  1. Hematologic Malignancy
  2. Chondroblastoma
  3. Eosinophilic Granuloma
  4. Giant cell tumor
  5. Ewing's Sarcoma
  6. Osteosarcoma
  7. Synovial Sarcoma
  • Causes
  • Benign Tumor
  1. Aneurysmal bone cyst
  2. Fibrous cortical defect
  3. Fibrous dysplasia
  4. Osteochondroma
  5. Osteoid Osteoma
  6. Pigmented villonodular synovitis