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Osteoarthritis
- 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