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114: OA, Infections and Tumors & How to Know When You’re Done Studying

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Osteoarthritis

Normal X-ray of the b/l knees. Normal join spaces and no osteophytes
Advanced arthritis with narrowing of the joint spaces and clear medial osteophytes on the both knees.
  • A degenerative joint disease characterized by a loss of cartilage, bony reformation and a narrowing of the joint space.
  • May occur in any joint including the knees, hips, ankles, hands, spine, shoulder and so on.
  • Most commonly occurring in patients over 40 years old and increasing incidence with age.
  • Trauma to a joint may result in osteoarthritis as well. When considering trauma remember
    • Gout
    • Rheumatoid arthritis
    • Joint infection
    • Chronic steroid use
    • Sickle cell

Clinical Presentation

  • Joint pain and stiffness
  • Often worse in the morning or after not using the joint for some time.
  • Joint swelling

Labs, Studies and Physical Exam Findings

  • Physical exam findings
  • Decreased range of motion
  • Joint effusion
  • Crepitus
  • Obvious deformity like significant varus or valgus
  • X-rays
    • Narrowing of joint spaces
    • Osteophytes – bony overgrowth

Treatment

  • Losing weight may decrease symptoms and arrest progression of disease
  • Physical Therapy to maintain flexibility and strength
  • Continue movement!
  • Medications
    • Acetaminophen
    • Tramadol
    • NSAIDS
      • Ibuprofen
      • Naproxen
      • COX-2 inhibitors like Celebrex
    • Intra-articular steroid injection provides temporary pain relief
    • Hyaluronic acid injections – Viscosupplementation
  • Surgical
  • Removal of osteophytes
  • Joint replacement
  • Joint fusion

Acute/chronic osteomyelitis

  • Bone infection
  • Hematogenous- spread through the blood. These are most commonly pediatric cases and long bones are most commonly affected.
  • Exogenous – Typically from an open wound or surgery
  • Staph Aureus the most common pathogen
  • Salmonella is the most common cause of osteomyelitis in a patient with sickle cell anemia
  • Chronic osteo comes and goes. It is treated with antibiotics and then it may come back months or years later.

Clinical Presentation

  • Pain, warm, red, tender
  • Open oozing wound
  • Foul smelling wound
  • Difficulty using limb

Labs, Studies and Physical Exam Findings

  • Warm, red, tender area
  • Swelling
  • X-ray will only show advanced stage disease
  • MRI
  • Bone scan
  • Bone biopsy

Treatment

  • At least 6 weeks of antibiotics
  • Surgical debridement
  • Remove hardware if there is any – plates, screws, anchors etc.

Septic arthritis

  • Infection in the joint
  • Medical emergency as the joint may be destroyed in a relatively short time.
  • Can occur by
    • Hematogenous pathway from another infection site
    • Penetrating trauma
  • Staph Aureus is the most common cause

Clinical Presentation

  • Pain and swelling in the joint
  • Fever

Labs, Studies and Physical Exam Findings

  • Joint is
  • Swollen
  • Red
  • Tender
  • Decreased ROM
  • C reactive protein and erythrocyte sedimentation rate are elevated
  • X-ray
  • MRI
  • Aspiration (arthrocentesis) is necessary for diagnosis with WBC count over 50,000 but usually much higher

Treatment

  • IV antibiotics
  • Surgical washout of the affected joint within hours
  • Removal of any hardware is often necessary

Neoplasm

  • Multiple myeloma is the most common primary malignant bone tumor
  • The most common primary malignancies which metastasize to the bone are prostate, breast and lung. Bone is the third most common area for metastasis.
  • Osteosarcomas occur most commonly between the ages of 10 & 20 years old
  • Sarcoma = cancer of cells which are mesenchymal in origin including bone, fat and vascular cancers. Breast, lung and colon cancer originate from epithelial cells and are usually carcinomas.

Clinical Presentation

  • Pain
  • Fatigue
  • Fever
  • Weight loss
  • Pathologic fracture

Labs, Studies and Physical Exam Findings

  • Alkaline phosphatase is elevated when bone is being remodeled.
  • X-ray
    • Lytic lesions are areas of the bone which appear to be eaten away. They may have sharp edges and no clear border.
    • Sunburst lesion on x-ray = osteosarcoma or Ewing’s sarcoma
  • CT/MRI
  • Bone scan
  • PET

Treatment

  • Chemotherapy and radiation work well on Ewing’s sarcoma
  • Surgical resection of the tumor often including an amputation