RT 208 Pathology Flashcards
Vitamin D
Absorption of calcium in the intestine. Activated by ultraviolet radiation
Vitamin A
Needed for bone resorption that occurs during normal development. Retarded development of bone occurs without it.
Vitamin C
needed for synthesis of collagen which is used by osteoblasts to make osteoid.
Pituitary Gland
Human Growth Hormone
Stimulates reproduction of cartilage cells in epiphyseal plates
Thyroid Hormone
Thyroid Gland -T3 and T4 stimulates the replacement of cartilage in epiphyseal plates. Excessive secretion halts bone growth. A deficiency causes stunted growth.
Calcitonin
calcium storage in bone
Sex hormones
Androgens (testosterone), and Estrogens . Testes, ovaries and adrenal gland (zona reticularis of adrenal cortex).
Parathyroid Gland
parathormone. Stimulates osteoclasts to release calcium into the blood stream.
Minerals
Calcium 25% Phosphorus 12% Magnesium 0.37% Potassium 0.7% Zinc .009% Copper .0009%
Protein
for Osteoid production
Etiology:
Vitamin C deficiency leading to inadequate production of collagen
S/S
Internal bleeding into joints, periosteum and mucus membranes, petechiae, ecchymoses, anemia, pallor, bleeding gums and loose teeth.
Tx
Restore vitamin C intake. 100-200 mg p.o. daily
Etiology:
Rate of bone resorption increases while rate of bone formation slows down causing loss of bone mass.
Lack of estrogens and androgens in post-menopausal women
and androgens in post-menopausal women
Nutritional disorders
not enough protein or calcium in diet
Disuse
Lack of exercise which is necessary for osteoid formation. “Atrophy”of disuse.
Example: patient’s whose extremities have been in a cast for six weeks.
Osteoporosis Treatment
Basically symptomatic and try to prevent additional fractures Estrogens to decrease bone resorption Fluoride to stimulate bone formation Calcium and Vitamin D Teach patient good body mechanics
Symptoms of Osteomalacia - Rickets
Etiology:
Sunlight stimulates ergosterol
Renal Rickets
Etiology
Vitamin D deficiency either due to inadequate dietary intake, malabsorption in gastrointestinal tract or too little sunlight.
Sunlight stimulates ergosterol in the skin and makes vitamin D active.
Vitamin D is necessary for the absorption of calcium and phosphorus in the GI tract.
Renal Rickets
kidney injury causes retention of phosphorus in the body which stimulates the parathyroid gland to release parathormone and increase calcium levels in the blood by removing calcium from the bone.
Osteomalacia
There is plenty of osteoid but no calcium to provide strength. Bow legs, knock knees result
Hyperparathyroidism - Primary
is where one or more of the parathyroid glands enlarge and increase the secretion of PTH (parathormone). Parathyroid adenoma accounts for 80% of this problem
Hyperparathyroidism - Secondary
Excessive compensatory production of PTH because of high levels of phosphorus in the blood due to renal problems. Hypocalcemia from inadequate dietary calcium can cause it too.
S/S
Kidney stones, chronic back pain from fx, neuromuscular and CNS (personality disturbances, depression, psychosis, and coma)
Osteitis DeformansPaget’s Disease
a slowly progressive metabolic disorder characterized by an initial phase of bone resorption (osteoclastic phase), followed by a reactive phase of abnormal bone formation (osteoblastic phase).
Osteitis DeformansPaget’s Disease - Etiology
exact cause is unknown but it is thought that viral infection (mumps) may trigger it years after the exposure. 5% of patient’s with Paget’s disease develop osteosarcoma.
Paget’s Disease
Paget’s disease occurs worldwide but is rare in Asia, Middle East, Africa and Scandinavia.
In United States approximately 2.5 million people over the age of 40, mostly men have the disease
.
S/S: Early stages patient may be asymptomatic. Pain may occur from impingement of abnormal bone on spinal cord. Cranial enlargement (frontal and occipital bones) involved.
Pagetic sites are warm, tender and susceptible to pathologic fracture.
Treatment - Paget’s Disease
Drug therapy: Calcitonin given sc or IM or etidronate given p.o. to retard bone resorption
Mithramycin (cytoxic antibiotic) to decrease calcium loss, urinary hydroxypoline and serum alkaline phosphatase
Surgery: to repair fracture sites or correct deformities
Other tx: aspirin, ibuprofen for pain (symptomatic)
Tumors of the Bone -Primary
originate in bone or bone components
Tumors of the Bone - Secondary
metastatic tumors from other cancers (breast, prostate, etc.) that spread to the bone via the blood stream (nutrient artery and branches) or by direct invasion (proximity). The cancer usually will appear in the metaphysis (area between diaphysis and epiphysis) where the nutrient artery enters the bone. Cancer cells get trapped in the capillary beds of the bone and start growing.
Primary tumor of the bone - Osteoma
Benign Age of patient - any Common site -Skull, ear, sinuses Etiology -Bony outgrowth in EAM. Bilateral, multiple lesions Tx: Surgical Excision
Primary tumor of the bone - Fibroma
Benign
Age of patient - any
Common site -Fibrous bone tissues
Etiology -Displaces bone cells
Primary tumor of the bone - Osteochondroma
Benign
Age of patient - Age 15 to 25
Common site Lower femur
Etiology -Most common benign tumor
Primary tumor of the bone - Chondroma
Benign
Age of patient - any
Common site = Phalanges of hands and feet
Etiology = Develops from cartilage
Primary Malignant Bone Tumors -Osteosarcoma
Age of patient - 10-25 Location - Metaphysis of long bones Femur Tibia Humerus
Comments - Most common
15% 5 year survival rate
Treatment - 1. Surgery:
(a) resection
(b) Amputation
2. XRT
3. Chemo
Primary Malignant Bone Tumors -Fibrosarcoma
Age of patient -Males
30 to 40
Location - Fibrous tissue surrounding bone
1. Flat bones
Comments - Vary rare tumor
Nonosseous origin
Treatment -
- Surgery:
a. Amputation - XRT
- Chemo
Primary Malignant Bone Tumors -Chondrosarcoma
Age of patient -Males
30 to 50
Location - Pelvis Femur Ribs Shoulder
Comments - Develops From cartilage Painless, slow growing
Treatment -
Surgery
XRT for palliation
Chemo
Primary Malignant Bone Tumors -Ewings Sarcoma
Age of patient -Males 10 to 20
Location - Lower ext. Femur Pelvis Tib/Fib Vertebrae
Comments -Bone marrow Poor Px Mets to lung
Treatment -
Surgery
XRT
Chemo
Primary Malignant Bone Tumors -Giant Cell Tumor
Age of patient - Females 18-50
Location -
Long bones
Knee area
Comments -Benign tumor that becomes malignant
Treatment -
Surgery
Curettage
Scraping away material from cavity or surface
Inflammatory Lesions of the Bone - Osteomyelitis
a pyogenic infection of bone that may be acute or chronic.
Etiology:
(a) Complication of an acute localized infection
(b) Hematogenous dissemination- bacteremia
(c) Traumatic implantation: GSW, compound fx
Most common bacteria is Staph Aureus, E. Coli, Proteus vulagaris Pseudomonas Aeruginosa
Terms:
(a) Sequestrum: dead bone that collects and drains
its way out through an abscess or sinus tract
(b) Involucrum: Necrotic bone stimulates periosteum to create new
bone at the site of the infection.
S/S: Patient may have pain, tenderness, heat, swelling and restricted movement in the infected bone.
Dx: History of injury
Blood Tests: leukocytosis, elevated Erythrocyte Sedimentation Rate (ESR)
Blood cultures:
Hematogenous dissemination
bacteremia
Traumatic implantation
GSW, compound fx
Osteomyelitis -Most common bacteria
Staph Aureus, E. Coli, Proteus vulagaris Pseudomonas Aeruginosa
Sequestrum
dead bone that collects and drains its way out through an abscess or sinus tract
Involucrum
Necrotic bone stimulates periosteum to create new
bone at the site of the infection.
Osteomyelitis: S/S
Patient may have pain, tenderness, heat, swelling and restricted movement in the infected bone.
Osteomyelitis: Dx:
History of injury
Legg-Calve Perthes – Coxa Plana
Etiology: Spontaneous vascular interuption causes necrosis of femoral head in 1-3 weeks
New blood supply causes bone resorption and deposition of new bone cells. Deformity may result from pressure on weakened area (6 mo)
New bone replaces necrotic bone (2-3 years)
S/S: Persistent limp that becomes more severe especially during second stage of disease.
Mild pain (hip, thigh or knee) that is aggravated by activity and relieved by rest. Severely restricted abduction and rotation of hip.
Osteomyelitis: Blood Tests
leukocytosis, elevated Erythrocyte Sedimentation Rate (ESR) Blood cultures:
Inflammatory Lesions of the Bone - Legg-Calve Perthes Disease (Coxa Plana)
It is a disease where vascular interruption of the blood supply to a bone causes ischemic necrosis of the head of the femur. This causes the femoral head to flatten. It occurs most frequently in boys aged 4 to 10. The disease runs it’s course in 3 to 4 years. It may lead to premature osteoarthritis in later life due to misalignment of the acetabulum and flattened femoral head.
Legg-Calve Perthes – Coxa Plana Etiology
Spontaneous vascular interuption causes necrosis of femoral head in 1-3 weeks
Legg-Calve Perthes S/S
Persistent limp that becomes more severe especially during second stage of disease. Mild pain (hip, thigh or knee) that is aggravated by activity and relieved by rest. Severely restricted abduction and rotation of hip.
Legg-Calve Perthes – Coxa Plana - DX
- Physical exam and history
- Hip x-ray taken every 3-4 months
- Aspiration and culture of synovial fluid
to rule out joint sepsis
Tx: Protect femoral head from further damage by containing it within the acetabulum.
3 months of bed rest with reduced weight traction then hip abduction splint or cast
Inflammatory Lesions of the Bone - Osgood-Schalatter Disease
Is a painful, incomplete separation of the epiphysis of the tibial tubercle from the tibial shaft. It is most common in adolescent boys and affects both knees.
Osgood-Schalatter Disease - Etiology
Trauma before the complete fusion of the epiphysis to the main bone. It may be a single violent trauma or repeated knee flexion against a tight quadraceps muscle or a deficient blood supply and or caused by genetic factors.
It occurs between the ages of 10 to 15 years old.
Osgood Schlatter Disease - S/S
Constant aching, pain and tenderness below the knee cap which worsens during any activity that causes forceful contraction of the patellar tendon on the tubercle.
Soft tissue swelling, heat and tenderness may be present
Osgood Schlatter Disease - DX
Physical exam: examiner forces the tibia into internal rotation while slowly extending the patient’s knee from a 90 degree flexion. At about 30 degrees flexion there is pain that subsides immediately with external rotation of the tibia
X-rays may be normal or show epiphyseal separation and soft tissue swelling for up to six months after onset.
TX: 6 to 8 weeks of immobilization through reinforced elastic knee support, plaster cast or splint. This allows revascularization and
re-ossification of the tubercle and minimizes the pull of the quadriceps muscle.
(2) Supportive treatment may include activity restrictions and cortisone injections into the joint to relieve tenderness.
(3) Surgery in extreme cases. It may be necessary to remove or “fix” the epiphysis or drill holes through the tubercle of the main bone for form vascular channels
Inflammatory Lesions of the Bone -Aseptic Necrosis
Etiology: Death of bone with secondary irritation and low grade inflammation
(a) Idiopathic: no known cause
(b) Associated trauma
S/S: The age group is between 5 to 15 years old.
Symptoms: pain, muscle spasm, and postural disorders. It is usually self limited and spontaneously regenerates. It is a slow process.
Common sites: Small bones of the wrist and ankle
NOTE: Scaphoid bone of the wrist is most common which is why we do a PA wrist with ulna deviation.
Treatment: Immobilization
Treatment: Immobilization and analgesics
Aseptic Necrosis - Etiology
Death of bone with secondary irritation and low grade inflammation
(a) Idiopathic: no known cause
(b) Associated trauma
Aseptic Necrosis - S/S
The age group is between 5 to 15 years old.
Symptoms: pain, muscle spasm, and postural disorders. It is usually self limited and spontaneously regenerates. It is a slow process.
