FMC Test 2 *Bone*

Question 1

What is the behavior of bones?

Answer 1

• Bones are influenced by diet hormones and biomechanics
• Cortical bone sustains load well
  -Bends but does not permanently deform
• Compressive forces shorten bone
  - Strongest
• Tensile forces elongates bone
  - Weakest

Question 2

What is the description of an Avulsion Fracture?

Answer 2

An injury to the bone where a tendon or ligament pulls off a piece of the bone

Question 3

What is the description of a Closed Fracture?

Answer 3

The fractured bone does not penetrate the skin, but may be seen under the skin, there is no contusion from external trauma

Question 4

What is the description of a Comminuted Fracture?

Answer 4

A Fracture that has more that two fragments of bone that have broken off. Its a highly unstable type of bone fracture with many fragments.

Question 5

What is the description of a Complete Fracture?

Answer 5

A Fracture in which the bone has completely fractured through its width

Question 6

What is the description of a Compound (Open) Fracture?

Answer 6

The bone breaks, and fragments of the bone penetrates though the body’s internal soft tissue and break though the skin from the inside. There is a high risk of infection if external pathogenic factors enter the interior of the body.

Question 7

What is the description of a Compression Fracture? Where does it generally occur?

Answer 7

Occurs when the bone is compressed beyond its limit of tolerance. (Generally occurs in the vertebral bodies due to a flexion injury or without trauma in patients with osteoporosis)

Question 8

What is the description of a Epiphyseal Fracture?

Answer 8

A fracture of the epiphysis and physis-growth plate. These injuries are classified using the Salter-Harris Classification.

Question 9

What is the description of a Greenstick Fraction?

Answer 9

A type of fracture that includes an incomplete fracture in which only one side of the bone breaks. The bone is usually “bent” and only fractures the outside of the bend. (Often seen in children, considered stable fracture)

Question 10

What is the description of a Hairline Fracture?

Answer 10

This bone fracture has minimal trauma to the bone and surrounding soft tissue. Its an incomplete fracture with no signifiant displacement and considered a stable fracture.

Question 11

What is the description of a Impaction Fracture?

Answer 11

Occurs when one fragment is driven into another. This type of fracture is common in tibial plateau fractures in adults

Question 12

What is the description of a Oblique Fracture?

Answer 12

A fracture that goes at an angle to the axis of the bone

Question 13

What is the description of a Pathologic Fracture?

Answer 13

Occurs when a bone breaks in an area that is weakened by another disease process. Causes can include: Tumors, infection, osteoporosis, or osteopenia and certain inherited bone disorders

Question 14

What is the description of a Spiral Fracture?

Answer 14

The bone was broken due to a twisting type motion. It is highly unstable and may be diagnosed as an oblique fracture. Resembles a corkscrew type that runs parallel with the axis of the broken bone.

Question 15

What is the description of a Stress Fracture? Where does it often occur?

Answer 15

Happens because of repeated microtrauma that disrupts bone formation process. This type of fracture is the most commonly seen by PTs, they often occur in the spine and lower extremities.

Question 16

What is the description of Bone Repair?

Answer 16

• Hematoma Formation (Inflammatory Stage)
• Soft Callus Formation (Repair Stage)3 level structure
  –Outer Proliferating Part
  –Cartilaginous Middle Part
  –Inner new boney trabecular part
• Hard Callus Formation (Remodeling Phase)
• Remodeling Phase
  –The bone is considered healed when the fracture line is no longer visible in an x-ray

Question 17

How does you determine if a bone needs surgical or non-surgical repair?

Answer 17

It depends on the degree of injury and involvement of supporting tissues

Question 18

What are some Surgical Repair options for Bones? (5)

Answer 18

• Percutaneous Pinning: Pins inserted through the skin to the cortex of the bone. (Pins can break)
• External Fixation: Pins proximal to distal to fracture to apply traction to decrease fraction while bars and wires outside of the skin allow for healing
• Open Reduction and Internal Fixation: Internal reduction of fracture then stabilized using plates and pins
• Locking Plates: Plates have threaded screw holes to fixate plate to bone
• Intramedullary Nailing: Pins or nails inserted into or through bones to provide stability

Question 19

What are some Non-Surgical Repair options for bones?

Answer 19

• Splints: Lie along the affected area aiming to immobilize the area (used for days to weeks)
• Casting: More rigid option, immobilizes while maintaining reduction of fracture
• Skeletal Traction: Usually used in the spine to override compressive action of the muscles of the area

Question 20

What are the effects of immobilizing a bone?

Answer 20

• Cartilage Degeneration (Without compression of a joint cartilage can soften)
• Decreased mechanical and structure of ligaments
• Decreased bone density
• Weakness or atrophy of muscles