Describing a Fracture

Question 1

What is a complete fracture?

Answer 1

the bone is broken through its full circumference and two or more bone fragments are created as a result

Question 2

What is an incomplete fracture?

Answer 2

a fracture where the bone may only be broken part of the way around the circumference of the bone (not as common in older animals, aka “Greenstick Fracture”)

Question 3

Short vs. long oblique fractures–>

Answer 3

Long is more than 2x diameter of the bone and short is less than 2x the diameter of the bone
oblique means fracture is at an angle across the short axis of the bone

Question 4

Spiral oblique is a ____ oblique with a ____

Answer 4

Long oblique with a twist

Question 5

______ _____ fractures are intended to assess prognosis, a descriptive term, prognosis also implied. Originally a human pediatric term

Answer 5

Salter-Harris Fracture

Question 6

KNOW SALTER HARRIS FX PICS

Answer 6

!!!!

Question 7

What is the most common salter harris fx?

Answer 7

4

Question 8

Which salter harris fx has the worst prognosis because growth plates are damaged so stunted growth leading to angular limb deformity?

Answer 8

Salter harris 5

Question 9

Salter harris ___ and __ does not go across jt surface

Answer 9

Salter harris 1 and 2

Question 10

What are the different types of external coaptation?

Answer 10

Robert jones bandage, modified robert jones bandage, Splint (lateral)

Question 11

Robert jones bandage-

Answer 11

used to immobilization of fractures and injuries distal to elbow and stifle; decreases and prevents edema formation and is used short term. Protects the limb, use large volume of cotton +/- splint material

Question 12

Modified Robert Jones Bandage-

Answer 12

aka soft padded bandage, which has the same goals but is not as large, often for longer term immobilization and support

Question 13

Splinting-

Answer 13

lateral splints are usually used, mason meta splints are splints with palmar/plantar application aka “spoon splints”, not used as lateral support; used for additional support and protection to the injured site, they are placed between gauze and tertiary layer

Question 14

What are the different components of external coaptation? (2)

Answer 14

Axillary coaptation and definitive coaptation

Question 15

used post op, generally short term use for a day days to a week or two is referred to as _____ _____

Answer 15

Axillary coaptation

Question 16

What is definitive coaptation?

Answer 16

casts, splints, goal is to immobilize the joint proximal and distal!!! Good fit needed to prevent injury to soft tissues (like from cast sores), monitor closed because they will need to be protected from wet, and beware that it will shift/patient will grow, reduce patient’s activity in this coaptation

Question 17

What are the advantages of external coaptation?

Answer 17

protection, minimal risk of contamination, less expensive, easy to apply, great for greenstick aka incomplete fractures, useful when concurrent soft tissue injuries are present to decrease swelling

Question 18

What are the disadvantages of external coaptation?

Answer 18

Limited to only using in fractures distal to the stifle or elbow. Some false sense of security, increased risk of malunion or nonunion, requires frequent changes, “Fracture Disease” may occur which includes stiffness, osteoarthritis (OA), cast sores, or contracture

Question 19

What are the possible coaptation-related complications?

Answer 19

Monitor all case on rads q 4 wks, swelling and edema, odor, non-union or malunion, soft tissue injury from muscle contracture or skin abrasion and dermatitis, muscle atrophy

Question 20

Fracture severity from least to most—->

Answer 20

1. incomplete (less severe)
2. simple- 2 piece fracture
3. comminuted- 2 segments of long bone but multiple little bone fragments
4. segmental- 3 or more circumferentially intact segments

Question 21

_____ fractures are always considered severe due to ____ damage and long term arthritis

Answer 21

Articular; cartilage damage

Question 22

Difference between primary and secondary bone healing:

Answer 22

Primary healing involves not much strain/distance between the fragments of bone unlike secondary healing which does involve strain, and increased distance between bone ends +/- much movement between bones.
Influenced via interfragmentary strain across the fracture gap

Question 23

Occurs when larger gap, increased motion, or higher strain occurs. Blood supply is damaged in the center causing a fx hematoma = _____ bone healing

Answer 23

Secondary bone healing

Question 24

What are the events occuring during the phases of bone healing?

Answer 24

Inflammation phase, repair phase, callus formation, remodeling phase

Question 25

Describe the inflammation phase-

Answer 25

i. Fracture hematoma forms after trauma, contraction and thrombosis of affected vessels minimize blood loss, then ischemia from interruption of blood flow, then local loss of radio-opacity of bone on rads (resorption of fragment ends mediated via prostaglandins and macrophages clean up the site), then bone gap will reappear and widen in 5-7 days after injury due to formation of new collagen via Fibroblast Factor

Question 26

Describe the repair phase-

Answer 26

Granulation tissue formation within 2-4 d post-trauma, hematoma acts on osteoconductive spacer (scaffolding for osteoblasts, fibroblasts, and chondrocytes to grow on), fibroblasts and chondrocytes migrate to site and begin to lay down the callus which is like a big bone scab made of cartilage that will hold things together temporarily and then go away (takes weeks to form a callus)

Question 27

Describe callus formation-

Answer 27

Repair phase “soft” callus forms within first 3 weeks, loosely organized collagen fibers, then mesenchymal stem cells form periosteum, endosteum, bone marrow, and adjacent soft tissue differentiate into chondrocytes--> “bridging callus” --> “hard callus” after mineralization of periosteum which CAN be seen on rads unlike bridging callus

Question 28

Describe the remodeling phase--

Answer 28

takes months to years, characterized by osteoclastic resorption and osteoblastic deposition of new bone, external callus gradually disappears and new bone is re-built via cutting cones which move across the fracture ends and produce osteoid which mineralizes to form longitudinally-oriented lamellar bone known as Haversian Remodeling

Question 29

What is biological healing and what is its goal?

Answer 29

Open but do not touch method, preserve the environment and do not disrupt the fx hematoma, goal is to align the fracture while minimally disrupting the surrounding extraosseous blood supply to maintain intraosseous bf and limit disruption of endosteum and periosteum

Question 30

What results from biological healing?

Answer 30

Secondary bone healing with earlier formation of callus

Question 31

BPM's and growth factors include...

Answer 31

Bone morphogenetic proteins and platelets, WBCs, Prostaglandins and interleukins and TNFs

Question 32

___ stimulates stem cells to differentiate into chondrocytes or osteoblasts

Answer 32

BMP's

Question 33

We can speed up bone healing by inserting ____ in the fracture at time of surgery to accelerate the healing process

Answer 33

BMPs

Question 34

What are some graft sources?

Answer 34

Autograft (from same p), allograft (from same species), xenograft (from diff. species), synthetic (non living source, commonly used)