Splint Bone and Proximal Sesamoid Bone Fractures Flashcards
Which splint bone has minimal articulation and weight transfer with the tarsal bones?
MT4
Provide axial support to carpus and tarsus
Splint bones
Is the accessory carpal bone medial or lateral?
Lateral
Is MT4 medial or lateral?
Lateral
What causes closed splint bone fractures?
Hyperextension of the fetlock
What causes open splint bone fractures?
External trauma
What may cause persistent lameness assoc. w/splint bone fractures?
Suspensory desmitis
How do you treat a proximal splint bone fracture?
Remove loose fragments and internal fixation
How much of a residual distal splint bone can you remove?
Less than 2/3
If you remove more than 2/3 of the distal splint bone, what other stabilization do you need?
Internal fixation of proximal fragment
What soft tissue is most commonly injured along with splint bones?
Suspensory ligament
When plating a splint bone fracture, why should you not engage MC3 with the plate?
Micomotion will cause persistent lameness
If you do have to engage MC3 with a plate, when must the plate be removed?
3-4mo later
Occurs in MC2 of young horses d/t direct trauma or ligamenous inflammation
Splint exostosis
What is the most common cause of splint exostosis?
One forelimb hits the inside of the other leg
How can you reduce inflammation at a splint exostosis site?
Local DMSO, infiltration w/steroids
How do you surgically treat exostosis?
Linear incision over site w/en bloc removal
There are no muscles or neurovascular structures directly over the splint bone between which landmarks?
Middle of splint bone to button
What are the 3 places to get a pulse on a horse?
Facial, transverse facial, and dorsal metatarsal artery
Where does the dorsal metatarsal artery run?
Between MT3 and MT4
Caused by bucked shins, dorsal metacarpal disease, or stress fractures
Periostitis and fracture of dorsal MC
Usually occurs in 3yr olds w/bucked shins as 2yr olds
Stress fractures
How can you prevent bucked shins with exercise modification?
Regular short distance breezing and less long distance galloping
What is the best treatment for a stress fracture?
Osteostixis w/screw
When should an osteostixis screw be removed?
60d post-op
How far apart are osteostixis holes?
10mm
What is the px for bucked shins for return to racing?
Good
What are the 6 types of proximal sesamoid bone fractures?
1: apical
2: mid-body
3: basal
4: abaxial
5: sagittal (axial)
6: comminuted
What causes a proximal sesamoid bone fracture?
Excessive tension from SL, trauma
What type of proximal sesamoid bone fracture is the most common?
Apical
What breeds are most commonly diagnosed w/proximal sesamoid bone fractures?
Racing breeds
How do you treat an apical (type 1) sesamoid fracture?
Arthroscopic removal or internal fixation if large
How do you treat a mid-body (type 2) sesamoid fracture?
Internal fixation w/lag screw or circumferential cerclage wire
Which breeds is cerclage wire used for mid-body sesamoid fractures?
Standardbred
Which internal fixation method is more superior for mid-body sesamoid fracture treatment?
Arthroscopic screw fixation
What radiographic view do you need for dx of abaxial (type 4) sesamoid fractures?
60* skyline view
How do you treat an abaxial sesamoid fracture?
Athroscopic removal if intra-articular, otherwise conservative management
Which type of sesamoid fracture involves origin of all distal sesamoidean ligaments and therefore carries a poor prognosis
Basilar (type 3) sesamoid fractures
