NOTES Ch 6-8: Problems or Conditions associated with

the Skeletal System & Joints

Imbalances between bone formation & resorption

1. Osteoporosis: bone resorption outpaces bone deposit

– Bone matrix remains normal but bones become more porous & lighter

– Spongy bone is most vulnerable (ex: head of femur, compression of vertebrae)

Treatments for Osteoporosis:

• Calcium & Vitamin D supplements

• Increased weight-bearing exercises

• HRT- hormone (estrogen) replacement therapy

Teenagers need at least 1200 mg. of calcium per day

• The recommended daily dietary allowance (RDA) for calcium, released in 1997 by the Institute of Medicine, varies by age group: – 0 to 6 months, 210 mg – 6 months to 1 year, 270 mg – 1 to 3 years, 500 mg – 4 to 8 years, 800 mg – 9 to 18 years, 1,300 mg – 19 to 50 years, 1,000 mg – 51 to 70 years, 1,200 mg

• Many nondairy foods are high in calcium, including the following: – Green vegetables, such as broccoli and kale (Swiss chard, spinach, and

rhubarb are not listed because the body cannot use their calcium content they contain substances called oxalates, which block calcium absorption)

– Fish with soft, edible bones, such as salmon and sardines – Yogurt with active cultures (may be a good source of calcium for many

people with lactose intolerance, as evidence shows that the bacterial cultures used in making yogurt produce some of the lactase enzyme required for proper digestion)

• Vitamin D is necessary for the body to absorb calcium, therefore a diet should provide an adequate supply of vitamin D. Sources of vitamin D include eggs and liver, as well as sunlight.

2. Osgood-Schlatter• Named for an American surgeon—Osgood and a

Swiss surgeon—Schlatter

• Caused by: an inflammation or partial separation of the quadricep tendon from the tibial tuberosity (caused by chronic irritation—usually from overuse of the Quadriceps muscle.)– May manifest as knee pain

• It is seen mostly in muscular, athletic adolescent boys who are in a growth spurt.

• Treatment: cut down on activity; avoid deep knee bending exercise; ice and elevate; wear braces

3. Rickets- “soft bones”• Bones are inadequately mineralized

in children– Osteoid is produced but calcium

salts are not deposited so bones soften & weaken

– Weight-bearing bones may fracture or bend & deform (symptom = pain when weight is put on the affected bone)

– Caused by: insufficient calcium and Vitamin D

4. Gigantism An abnormal condition

characterized by size and stature

It is most commonly caused by hypersecretion of growth hormone in early childhood.

There is excessive growth at the epiphyseal plates

*Robert Wadlow: the “Alton Giant”

*8 ft. 11 in (490 lbs.) when he died (from an infected blister)—tallest person ever recorded.

5. Acromegaly Excessive growth of

connective tissue and bone after the epiphyseal plates have closed

Caused by excess pituitary growth hormone

Characterized by a gradual growth in length of the bones of face, jaw and extremities

6. Dwarfism One type: Abnormally

low levels of pituitary growth hormone

This affects the whole body the whole body is

smaller but proportional

7. Achondroplastic dwarfism• This is the most common kind of

dwarfism.

– It is characterized by abnormal short limbs, a normal-sized trunk, large head with a depressed nasal bridge and small face

– Also, stubby hands and lordosis

– The condition results from an inherited defect in endochondral bone-forming tissue

– intelligence is normal!

8. Spina Bifida• Spina Bifida is one of the most common

birth defects of the brain and spinal cord.

• The bones of the spine do not completely form, and the spinal canal is incomplete.

• This allows the spinal cord and meninges (the membranes covering the spinal cord) to protrude out the child's back.

9. Abnormal Spine Curves

1) Scoliosis:– Scoliosis may start in infancy

but is most frequently seen in adolescence. It is more common in females by a 2:1 ratio.

– The cause of the most common form of scoliosis is unknown—genetics are a factor

– In mild forms, the condition may be barely noticed; whereas in severe forms there is significant disfigurement, back pain and postural fatigue.

2) Lordosis: An abnormal accentuated

arch in the lower back (“swayback”).

– Everyone has "lordosis". The term simply describes the curvature.

– People born with greater lordosis MAY be subject to more frequent backaches.

– The greater the degree of lordosis, the greater is the force that the lower spine structures have to contend with

3) Kyphosis: Kyphosis is the abnormal

curvature of the upper spine (hunched

shoulders/ “hunchback”).

– Kyphosis may occur in children, adolescents, or adults. Adolescent kyphosis, may result from growth retardation or a disorder in the vertebrae during periods of rapid growth.

– Other causes of kyphosis include infection, inflammation, disk degeneration, osteoporosis of the vertebrae, arthritis, polio, compression fractures of the vertebrae, cancer, tuberculosis, or poor posture.

10. Herniated (“slipped”) Disc• Involves rupture of the

annulus fibrosus followed by protrusion of the spongy nucleus pulposus– Treated with: traction, bedrest,

painkillers, or surgery

11. TMJ (“lock-jaw” syndrome)• Location: where the mandible

articulates with the temporal bone- temporomandibular joint

• Characterized by: dull pain around the ear, tenderness of jaw muscles, clicking/popping noise when opening or closing the mouth, headache, tooth sensitivity, abnormal wearing of teeth

• Treatment: application of moist heat or ice, soft diet, aspirin, muscle restraining, adjusting or reshaping the teeth, orthodontic treatment or surgery

12. Bursitis• Inflammation of bursa; usually

caused by direct injury or excessive friction but may result from bacterial infection– Ex: prolonged leaning on one’s

elbow student’s elbow

– Symptoms: pain made worse by joint movement, redness, & swelling

– Severe cases are treated by injecting anti-inflammatory drugs into the bursa or by needle aspiration to remove excess fluid

13. Tendonitis

• microscopic tears to tendon lead to inflammation of tendon sheaths– Typically caused by overuse

• Symptoms & treatment (rest, ice, & anti-inflammatory drugs)

14. Arthritis• Term “arthritis” includes

over 100 types of inflammatory or degenerative diseases that damage the joints– Depending on the specific

form, synovial membrane, articular cartilages, or articulating bones may be involved

• Initial symptoms: pain, stiffness, swelling of the joint

15. Rheumatoid arthritis• Autoimmune disease: body’s immune system

attacks its own tissues• RA begins with inflammation of the synovial

membrane of the affected joints; without treatment, synovial fluid accumulates and eventually leads to scar tissue on the articular cartilages that then become ossified and the bone ends fuse together– Usually arises between 40-50 yrs. but can be any age– 3x as many women as men– Occurs in more than 1% of Americans

16. Fractures• Fractures of the bones are classified in a number of ways.

– A simple fracture involves a single fracture line through a bone.

– A comminuted fracture is one in which the bone has been fractured into two or more fragments.

– An open or compound fracture is one in which the fractured bone penetrates the skin.

**Bone Marrow Transplants**PURPOSE: to treat cases of:1. Aplastic anemia (low blood cell count)2. Certain types of leukemia3. Severe combined immunodeficiency disease

(Inherited deficiency of infection fighting blood cells)

4. Hodgkin’s disease (cancer of lymphocytes)5. Non-Hodgkin’s lymphoma (cancer of different lymphocytes)6. Hemolytic anemia (RBC’s rupture faster than can be

replaced)7. Sickle-cell anemia8. Multiple myeloma (cancer of plasma-B cells)

GOAL: to replace unhealthy bone marrow stem cells with healthy ones

**Bone Marrow Transplants**PROCEDURE:• In order to transfer bone marrow from a donor to a patient; bone

marrow must be very closely matched to that of the recipient

1. Recipient is usually irradiated to destroy their own red marrow & immunosuppressive drugs are administered

2. Donor marrow is aspirated from the hip-bones, mixed with heparin (anticoagulant), then passed through screens; the suspension of bone marrow cells is treated to remove T-cells of the donor

3. These cells are then injected into a vein of the recipient; The cells in the suspension pass through the lungs, enter the general circulation, and hopefully reseed and grow in the marrow cavities of the recipient’s bones.

Common Joint Injuries Sprains• Occurs when the ligaments reinforcing a joint

are stretched or torn– Common in the ankle, knee, and lumbar region of

the spine– Sprains heal slowly because ligaments are poorly

vascularized– They also tend to be painful and immobilizing– A completely torn ligament requires surgery

• Must be performed quickly to prevent the ligament from turning to “mush”

• Important ligaments may also be replaced with other tendons or collagen bands

Cartilage Injuries• Usually involves tearing of the knee menisci, growth

plate fissures, and overuse damage to articular surfaces in other joints– May feel a snap or a pop– Cartilage injuries are becoming increasingly more common

in competitive young athletes

• Treatment– Cartilage is avascular so it does not repair itself– Cartilage fragments called “joint mice” can become loose

and interfere with the joint function and cause it to lock– Damaged cartilage is generally removed by arthroscopic

surgery – Removal of the meniscus does not impair joint function,

but causes the joint to be less stable

Dislocations• Occurs when bones are forced out of their normal

position at a joint– May also be accompanied by sprains, inflammation,

and joint immobilization– Common causes include a serious fall and contact

during sports

• Treatment– Dislocations must be “reduced”– This means a physician must realign the bones

 • Also, repeat dislocations are not uncommon

because the initial dislocation may stretch out the joint capsule and supporting ligaments