Worksheet: MSP Lab 1 - Fracture

Question 1

what is the normal organic:inorganic ratio for children?

Answer 1

1:1

Question 2

what is the normal organic:inorganic ratio for adults?

Answer 2

1:4

Question 3

what is the normal organic:inorganic ratio for elderly?

Answer 3

1:7

Question 4

what is elasticity in bone?

Answer 4

ability of bone to return to its original shape on removal of force

Question 5

what is plasticity in bone?

Answer 5

property of bone being permanently deformed by a force w/o breaking

Question 6

what does the yield point indicate?

Answer 6

point of stress where plastic deformation begins

Question 7

what happens when stress exceeds the ultimate yield point?

Answer 7

Fracture

Question 8

how does elasticity and plasticity change from normal adult bone to elderly bone?

Answer 8

decreases (amount of stress before yield point/ultimate yield point decreases)

Question 9

how does elasticity and plasticity change between normal adult bone and pediatric bone?

Answer 9

children have higher elasticity + plastcity; require increased stress to reach yield points compared to adults

Question 10

what Fxs in children are more common because of their elasticity/plasticity levels? give 2 examples of this type of Fx.

Answer 10

Incomplete Fxs; Greenstick; Torus

Question 11

The organic component of bone contributes to ___?

Answer 11

elasticity, plasticity, and tensile strength

Question 12

The inorganic component of bone contributes to ___?

Answer 12

rigidity and compressive strength

Question 13

an increased organic:inorganic ratio results in (increase/decrease) brittleness

Answer 13

decreased

Question 14

an decreased organic:inorganic ratio results in (increase/decrease) brittleness

Answer 14

increased

Question 15

(Station 2, Gross image 1) what stage of Fx repair is shown? what features can be seen in this stage? explain the cellular events that occur in this stage.

Answer 15

Inflammatory; Sharp, jagged fx line begins to smooth; Necrosis + macrophage activity, fibroblasts migrate, lay down cartilage, hematomas ‘filling gaps’, Procallus

Question 16

(Station 2, Gross image 2) what stage of Fx repair is shown? what features can be seen in this stage? explain the cellular events that occur in this stage.

Answer 16

Reparative; procallus conversion to boney callus produces “hazy cloud”, smoothes edges of fx; Neurovascularization/angiogenesis introduces O2 into anoxic cartilage/procallus, Osteoblasts migrate + convert procallus -> boney callus, Necrotic debri clean-up

Question 17

(Station 2, Gross image 3) what stage of Fx repair is shown? what features can be seen in this stage? explain the cellular events that occur in this stage.

Answer 17

Remodeling; adjusts strength + shape via Wolff’s law; Callus formed around fx begins remodeling

Question 18

(Station 3, CT scan) what stage of Fx repair is shown? what has NOT occured? describe the outcome of the Fx and the cellular events that are occuring.

Answer 18

Remodeling; Clinical union has NOT occured most likely due to inadequate formation of blood supply (lack of immobilization/stabilization); Pseudoarthrosis; Callus formation w/ osteoblastic activity (seals bone while Fx is unstable), Wolff’s law

Question 19

(Station 4, Radiograph 1) what specific name(s) apply to this Fx? what stage of Fx repair is shown? Explain the cellular events that are occuring,including the type of cells involved.

Answer 19

Complete, Transverse, Non-comminuted, Open (?); Inflammatory; Necrosis, ruptured BVs, hematoma, torn periosteum = pain; PMNs, Osteoclasts, Macrophages

Question 20

(Station 4, Radiograph 2) what specific name(s) apply to this Fx? what stage of Fx repair is shown? Explain the cellular events that are occuring,including the type of cells involved.

Answer 20

March Fx; Reparative; Osteoclasts + mononuclear cells clean-up debris, neovascularization/angiogenesis, callus begins = Hazy cloud osteoblastic activity

Question 21

(Station 4, Radiograph 3) what specific name(s) apply to this Fx? what stage of Fx repair is shown? Explain the cellular events that are occuring,including the type of cells involved.

Answer 21

Salter-Harris Fx Type II, Complete, Open; Inflammatory; Necrosis, ruptured BVs, hematoma, torn periosteum = pain; PMNs, Osteoclasts, Macrophages

Question 22

What is a March Fx?

Answer 22

Fatigue Stress Fx of 2nd or 3rd Metatarsals

Question 23

What is a Fatigue Fx?

Answer 23

Abnormal stress on normal bone (repetitive stress causes gradual micro-fracture formation)

Question 24

What is a Salter-Harris Fx?

Answer 24

Fx involving the Physis (growth plate)

Question 25

What type of Salter-Harris Fx goes straight across the physis?

Answer 25

Type I

Question 26

What type of Salter-Harris Fx goes across + above the physis?

Answer 26

Type II

Question 27

What type of Salter-Harris Fx goes across + lower/below the physis?

Answer 27

Type III

Question 28

What type of Salter-Harris Fx goes through the physis, or in other words splits the physis in two?

Answer 28

Type IV

Question 29

What type of Salter-Harris Fx creates an erasure of the physis/growth plate, or in other words crushes the physis?

Answer 29

Type V

Question 30

(Station 5, Case Study 1) A 71 year old woman reported to the ER w/ pain in her hip and thigh after stumbling at the grocery store. She has a Hx of Breast cancer that was treated and went into remission 40 years prior. She has also been receiving drug therapy for high blood pressure for the past 8 years. Examine radiograph 1. What evidence of bone abnormalities are seen? How would you treat this patient? She returns 12 days later citing continued pain in her hip and thigh along with mobility issues. Examine radiograph 2. Any alignment or bone abnormalities? What is the name for a Fx that isn’t initially visible radiographically? Additional tests confirm that she has osteoporosis; knowing this, what type of Fx is this?

Answer 30

(Gotta fill in when/if I have time); Occult Fx; Stress Insufficiency Fx

Question 31

What is an Occult Fx?

Answer 31

Fx that isn’t initially visible radiographically

Question 32

What is an Insufficiency Fx?

Answer 32

Normal stress on diseased bone (form of Pathological Fx)