Exam 2: Splint Bone and Proximal Sesamoid Bone Fractures

Question 1

Metacarpus/Metatarsus 2 and 4

are better known as

Answer 1

Splint bones

Question 2

Most splint bones articulate with carpal and tarsal bones,

except for ______,

which has minimal articulation and weight transfer

with the 4th tarsal bone

Answer 2

MT4

Question 3

What are the causes of closed splint bone fractures?

Answer 3

Hyperextension of the fetlock

Question 4

What are the causes of open splint bone fractures?

Answer 4

External trauma

Question 5

T/F:

Many splint bone fractures can be treated

successfully with rest alone

Answer 5

TRUE

Question 6

_______ desmitis (inflammation of the ligament)

can be related to splint bone fractures and

can result in PERSISTENT LAMENESS

Answer 6

Suspensory

Question 7

Why is it important to evaluate splint bone fractures

using serial ULTRASOUND?

Answer 7

Because suspensory desmitis can be related to the fracture

and cause persistent lameness

Question 8

What is the most common location for

a splint bone fracture?

Answer 8

DISTAL 1/3 of the bone

Question 9

How are splint bone fractures diagnosed?

Answer 9

RADS + U/S

Question 10

What type of radiograph is required for

dx of splint bone fracture?

Answer 10

DLpmo

Question 11

What type of surgical procedure is indicated for

select cases of splint bone fracture?

Answer 11

Segmental Ostectomy

removal of fracture fragments and residual distal splint bone

Question 12

During segmental ostectomy,

DO NOT REMOVE MORE THAN _________

of the DISTAL splint bone

Answer 12

2/3

Question 13

Fracture of this splint bone is the

exception to the rule, and more than 2/3 of the distal splint

bone can be removed via segmental ostectomy

Answer 13

MT4

Question 14

If you must remove greater than 2/3 of the distal splint bone,

_________ of the proximal fragment is necessary

Answer 14

internal fixation

Question 15

If plating a splint bone fracture,

DO NOT ENGAGE ________,

because there is micromovement between them

and this will result in persistent lameness

Answer 15

MC3

Must remove plate within 3 months if MC3 is engaged

Question 16

This radiographic view is used to diagnose

splint bone fractures

Answer 16

DLpmo

Question 17

What’s your dx?

Answer 17

Splint bone fracture

Question 18

A a benign outgrowth of cartilaginous tissue on a bone

is known as

Answer 18

exotosis

Question 19

Splint exotosis is most common in

_____ horses, and usually affects

this particular splint bone

Answer 19

Splint exotosis is most common in

young horses, and usually affects

MC2

Question 20

Splint exotosis usually occurs on the

______ aspect of the limb

Answer 20

medial

Question 21

What can cause the condition seen on this radiograph?

Answer 21

Splint exotosis:

Direct trauma

Ligament inflammation (desmitis)

Question 22

What are your conservative treatment options for

treatment of splint exotosis/proliferative periostitis?

Answer 22

Rest

NSAIDs

Local DMSO

Infiltration with CORTICOSTEROIDS

Question 23

En bloc removal is the surgical option for treatment of

splint exotosis/proliferative periostitis.

The most important aspect of post-op treatment is

Answer 23

EXCELLENT bandaging

or may recur

Question 24

For en bloc removal of splint exotosis/proliferative periostitis,

a tourniquet is placed proximally,

and an incision is made directly over the splint bone.

Why must you be careful not to move off of the

splint bone?

Answer 24

Because NEUROVASCULAR bundle is deep to it

Question 25

What 3 places are used to find a pulse in a horse?

Answer 25

Facial artery Transverse Facial artery Dorsal Metatarsal artery

Question 26

Describe the location of the ## Footnote *dorsal metatarsal artery*

Answer 26

Runs between the lateral splint bone MT4 and MT3

Question 27

What is your diagnosis?

Answer 27

Dorsal cortical fracture of MC3

Question 28

Dorsal cortical fractures of MC3 are categorized as \_\_\_\_\_\_\_\_\_ fractures

Answer 28

stress

Question 29

Young horses with bucked shins are at risk for this type of fracture

Answer 29

Dorsal cortical fracture of MC3

Question 30

How do you prevent bucked shins which can help to avoid dorsal cortical stress fractures of MC3?

Answer 30

Gait and Speed Training *Less **long distance** galloping*

Question 31

How are dorsal cortical stress fractures of MC3 treated medically?

Answer 31

rest, NSAIDs, exercise programs

Question 32

How are dorsal cortical stress fractures of MC3 treated surgically?

Answer 32

**Osteostixis** (alone or in combo with a screw) BEST is combination with screw removal at **60 days**

Question 33

What is the mechanism of action of osteostixis in the treatment of dorsal cortical stress fractures of MC3?

Answer 33

Creates holes to bring **mesenchymal cells** from the **medullary canal** to the surface

Question 34

For osteostixis, you must drill _______ to the fracture and place a single \_\_\_\_\_\_\_\_\_ **22mm** positional screw

Answer 34

For osteostixis, you must drill _perpendicular_ to the fracture and place a single _unicortical_ **22mm** positional screw

Question 35

6 - 8 osteostixis holes are drilled \_\_\_\_\_mm apart and drilled towards the MEDULLARY CANAL

Answer 35

10 mm

Question 36

What is a **saucer fracture**?

Answer 36

A type of bucked shin fracture in which a saucer shaped piece of bone is separated from the front of the cannon bone (MC3)

Question 37

What is this radiograph showing?

Answer 37

Osteostixis and screw placement for treatment of a dorsal cortical stress fracture of MC3

Question 38

Classify the proximal sesamoid bone fracture: What is 1?

Answer 38

Apical

Question 39

Classify the proximal sesamoid bone fracture: #2

Answer 39

Mid-Body

Question 40

Classify the proximal sesamoid bone fracture: #3

Answer 40

Basal

Question 41

Classify the proximal sesamoid bone fracture: #4

Answer 41

Abaxial

Question 42

Classify the proximal sesamoid bone fracture: #5

Answer 42

Sagittal (Axial)

Question 43

Classify the proximal sesamoid bone fracture: #6

Answer 43

Comminuted

Question 44

What is the most common type of proximal sesamoid bone fracture?

Answer 44

#1: APICAL

Question 45

What are the causes of proximal sesamoid bone fracture?

Answer 45

Excessive suspensory ligament tension Trauma

Question 46

proximal sesamoid bone fractures are most commonly seen in these types of horses

Answer 46

Racing breeds

Question 47

How are **Apical** sesamoid fractures treated? What is the prognosis?

Answer 47

**Arthroscopic removal** Prognosis = GOOD

Question 48

How are **mid-body** sesamoid fractures treated? What is the prognosis?

Answer 48

Internal fixation with **lag screw (best**) or cerclage wire + CAST

Question 49

How are **Abaxial (#4)** sesamoid fractures treated? What is the prognosis?

Answer 49

**Intra-**articular = Arthroscopic removal **Extra-**articular = Conservative management Prognosis = Fair to Good

Question 50

This type of sesamoid bone fracture can be easily missed on radiographs

Answer 50

Abaxial

Question 51

This type of radiograph is required in order to see if an abaxial sesamoid fracture is intra-articular

Answer 51

60 degree skyline oblique

Question 52

This type of sesamoid fracture has a POOR prognosis because it is the origin of all distal sesamoidean ligaments

Answer 52

BASAL (#3)

Question 53

A basal sesamoid fracture is also known as

Answer 53

BUST UP

Question 54

There is an inverse relationship between \_\_\_\_\_\_\_\_\_\_ length and return to racing in regards to basal sesamoid fractures

Answer 54

dorsopalmar