Ch 51: Alterations in Musculoskeletal Function; Trauma, Infection, and Disease

What is osteomyelitis?

• Severe pyogenic infection of bone and local tissue

• Inflammation (itis) of the bone (osteon) marrow (myelo)

Describe the ways that the organism can reach the bone? Provide examples.

• Bloodstream → infectious agent is introduced by blood from infection elsewhere in the body

• Adjacent soft tissue → caused by burns, sinus disease, trauma, malignant tumor necrosis, periodontal infection, infected pressure ulcer

• Direct introduction of organism → direct infection causes open fracture, penetrating wounds, surgical contamination, or insertion of prostheses, metal plates, or screws

In which type of diseases or populations can you expect osteomyelitis to occur?

• Children < 16 y/o (avg age 6 y/o) and elderly

• IV drug users

• Indwelling intravascular catheters/central line

• Diseases:

  • Sickle cell anemia

  • Chronic granulomatous disease (Sarcoidosis, Chron’s disease, TB, etc.)

What are the most common pathogens for osteomyelitis?

Staphylococcus aureus followed by Streptococcus Pneumoniae

What are the clinical manifestations for children with osteomyelitis?

High fever and pain at the sight of bone development

What is Brodie abscess?

Subacute osteomyelitis → localized infection enclosed by fibrotic tissue

What are the clinical manifestations for adults with osteomyelitis?

• Fever

• Malaise

• Anorexia

• Night sweats

• Weight loss

What are the potential healing complications with osteomyelitis?

• If osteomyelitis not managed or if treatment not sufficient → necrotic bone separates from healthy bone into dead segments → sequestra → chronic osteomyelitis

• Abscess, or chronic infection may occur

• Involucrum → prevents successful effects of antibiotics

What is the treatment for osteomyelitis?

• 4 to 6 weeks of antibiotic therapy (IV)

• Abscess formation may require debridement

• Amputation

What is scoliosis?

• Lateral curvature of the spine (10° or higher)

• S- or C-shaped

• Idiopathic or

• Consequence of

  • Congenital disorder (Hemi-vertebrae)

  • Connective tissue disorder (Marfan’s Sx)

  • Neuromuscular disorder (Cerebral palsy)

What are the clinical manifestations for scoliosis?

Appears after puberty

• Asymmetry of shoulders, hips, chest wall

• Possible respiratory problems

• GI dysfunctions

Describe nonstructural scoliosis.

• Resolves when the patient bends to the affected side

• No vertebral rotation or bony deformity of the vertebrae is present

• Can be related to postural problems, inflammation, or compensation due to leg discrepancy

Describe structural scoliosis.

• Fails to correct itself on forced bending against the curvature and has vertebral rotation

• Involves deformity of the vertebrae and asymmetric changes in hip, shoulder, and rib cage positions

Is scoliosis progressive? (note: one classification is progressive and the other is not)

• Nonstructural scoliosis → NOT progressive

• Structural scoliosis → PROGRESSIVE

What is the treatment for scoliosis?

• Bracing

• Exercises

• Surgical interventions with spinal alignment

  • ≥ 40-50 °

What is the most common metabolic bone disease?

Osteoporosis

What influences the rate of bone loss?

• Genetics

• Estrogen level

• Family Hx

When does osteoporosis occur?

When the rate of one resorption is greater than that of bone formation

• Normal osteoblastic and osteoclastic balance is disrupted

• Mineral and protein matrix components are decreased

• Leads to fragile bone → fractures

What are the risk factors of osteoporosis?

• Family history

• Estrogen deficiency

• Small frame

• Caucasian or Asian race

• Menopause

• Disease (Cushing dx, scurvy [vit. C. def.)

What are the clinical manifestations of osteoporosis?

• Shortened stature

• Muscle wasting

• Back muscle spasms

• Difficulty bending over

• Fractures ( Colles fracture of wrist, vertebral compression fracture)

• Kyphosis

How is osteoporosis diagnosed?

• Based on graduations of bone mineral density (BMD)

• Measured by dual energy x-ray absorptiometry (DXA)

  • T-scores

What does a T score of greater than or equal to -2.5 indicate?

Presence of osteoporosis

What does a T score between -1.0 and 2.5 indicate?

Osteopenia (low bone density/mass)

How is osteoporosis treated?

• Calcium and vitamin D supplements

• Exercise (weight-bearing)

• Bisphosphonates (Alendronate → antiresorptive agent)

• Recombinant human parathyroid hormone (anabolic agent/building)

What is the difference between rickets and osteomalacia?

Rickets:

• Deficits in mineralization of newly formed one matrix in the growing skeleton (children)

• Before puberty

Osteomalacia:

• Deficits in mineralization of newly formed bone matrix in the mature skeleton (adults)

• After puberty

What are the clinical manifestations of rickets and osteomalacia?

• Kyphosis (hunchback)

• Genu valgum → knock knee (inward knees)

• Genu varum → bow leg

• Pain in adults

What causes rickets and osteomalacia?

Inadequate concentration of

• Vitamin D

• Calcium or phosphorus

• Poor vitamin D metabolism

• Renal disease

How are rickets and osteomalacia treated?

Supplementation with vitamin D, calcium, and/or phosphorus

What is multiple myeloma?

• The most common primary tumor of bone

• Slowly growing bone marrow malignancy

What organs/systems does multiple myeloma affect?

• Kidneys

• Immune system

• Circulatory system

What are the clinical manifestations of multiple myeloma?

• Bone pain is a predominant symptom

• Pathologic fractures & hypercalcemia

• Kidney dysfunction

• Neurologic symptoms

• Unexplained anemia

How is multiple myeloma diagnosed?

• Homogenous immunoglobulin is present in urine and serum

• Bone marrow aspiration and biopsy

• Imaging tests

How is multiple myeloma treated?

• Aggressive combination chemotherapy

• Local radiation

• Survival >2-3 years → <10%

What is muscular dystrophy?

• Group of genetically determined myopathies characterized by progressive muscle weakness and degeneration

• Muscle tissue is replaced by fat and fibrous connective tissue

How is muscular dystrophy classified?

• Classified by the pattern of

  • Inheritance

  • Age of onset

  • Distribution of muscular weakness

What is the etiology and pathogenesis of Duchenne muscular dystrophy?

• Inherited as X-linked trait (only in MALES, especially boys)

• Muscle cells deficient in the protein dystrophin → weakens cell membrane → allows extracellular fluid to leak into cell → muscle necrosis and degeneration

What are the clinical manifestations for Duchenne muscular dystrophy?

• Diseases begins at birth and is usually apparent by age of 3

• Calf muscles enlarged due to

  • Infiltration of fat cells and

  • Degeneration of muscle fibers

• Distal muscle involvement leads to:

  • Frequent falling by the age of 5 or 6

  • Most children are confined to a wheelchair by ages 12-14 years old

How is Duchenne muscular dystrophy treated?

• Appropriate education of patient and family

• Corticosteroid therapy and preservation of function

What is myasthenia gravis?

• A chronic autoimmune disease

• Affects neuromuscular function of voluntary muscles

• Characterized by muscle weakness and fatigability

What is the etiology of myasthenia gravis?

• Acetylcholine receptor antibodies are produced → destroys or blocks acetylcholine receptors of the muscle end-plate of neuromuscular junction → impair the transmission of acetylcholine activity across the junction → muscle weakness and fatigability

What is the pathogenesis of myasthenia gravis?

Myasthenia crisis

• A complication of myasthenia grave that can result from insufficient medication, emotional stress, trauma, infection, or surgery

• Sudden increase in BP and pulse

Is myasthenia gravis more common in men or women?

Women

What age is the peak onset of myasthenia gravis?

20-30 years old

What are the clinical manifestations of myasthenia gravis?

• Painless muscle weakness

  • Begins with ocular and cranial muscles

  • Proximal limb muscles

  • Improves by rest and exacerbated by repetitive use

What is the treatment for myasthenia gravis?

• Anticholinesterase inhibitors

• Corticosteroids

• IV immunoglobulin

• Plasmapheresis

• Immunosuppressive agents

• Thymectomy if no response to medications

What is myasthenia crisis?

A complication of myasthenia gravis

What is the etiology of myasthenia crisis?

• Insufficient medication

• Emotional stress

• Trauma

• Infection

• Surgery

What are the clinical manifestations of myasthenia crisis?

Sudden increase in BP and pulse

What is cholinergic crisis?

A complication of myasthenia gravis

What is the etiology of cholinergic crisis?

Excessive medication being given to patients with myasthenia gravis

What are the clinical manifestations for cholinergic crisis?

• Fasciculations, especially around the mouth

  • Involuntary rapid muscle twitches that are two weak to move a limb but are easily felt by patients and seen or palpated by clinicians

Do you know SLUDGE?