Chapter 94 - Splint Bones

Question 1

1. What are the functions of the splint bones? (2)

Answer 1

• Support and stabilization
• Site for important carpal and tarsal ligament insertions

Question 2

2. Traumatic injuries of the splint bones are influenced by (3)

Answer 2

• Relative anatomic exposure
• Nature of the horse
• Equine management practices

Question 3

3. The proximal aspects of the splint bones articulate with the _________ bones and provide _____ support to these structures.

Answer 3

• Carpal/tarsal cuboidal bones
• Axial

Question 4

4. In the front limb, MC2 has a ______ shaped articulation and carries (more/less) weight than MC4 and its ______ configuration.

Answer 4

• Flat
• More
• Oblique

Question 5

5. What bones does MC2 articulate with?

Answer 5

• 2nd carpal bone
• 3rd carpal bone

Question 6

6. What bones does MC4 articulate with?

Answer 6

• 4th carpal bone

Question 7

7. The minimal articulation of splint bone ______ results in minimal weight bearing.

Answer 7

• MT4

Question 8

13. What structure of the hind limb is particularly at risk of injury following trauma to the 4th metatarsal bone?

Answer 8

• The lateral dorsal metatarsal artery

Question 9

8. What are the 3 soft tissue attachments of the splint bones?

Answer 9

• Metacarpal/tarsal interosseous ligament
• Palmar metacarpal fascia/plantar metatarsal fascia
• Distal ligament structure from the splint button to the condyle

Question 10

10. What ligament connects the splint bones to the respective cannon bone?

Answer 10

• The metacarpal/metatarsal interosseous ligament

Question 11

12. What tissue connects the distal end of the splint bone to the condyle

Answer 11

• Ligament of the button of the splint

Question 11

9. What bones does the metacarpal interosseous ligament connect?

Answer 11

• The MC3 and the MC4 and MC2 bones, respectively

Question 12

11. What is the connective tissue that attaches on the medial and lateral splint bones of a limb, covering the flexor tendons along the proximal extent of the limb?

Answer 12

• The palmar metacarpal fascia or plantar metatarsal fascia

Question 13

14. What is the cause of ‘splints’ in young horses?

Answer 13

• The small MC/MT bones are mobile relative to the adjacent MCIII/MTIII , and axial forces result in the stress and shearing of the interosseous ligament and periosteum. A synostosis between the splint bone and the MC3/MT3 results in stabilization and resistance to strain and shear

Question 14

16. Metacarpal fusion has an estimated prevalence of _____%

Answer 14

• 95%

Question 15

15. Which bone is most commonly affected by splints/exostosis and why?

Answer 15

• The MCII
• It has the larger articulation with the carpal bones and more extensive soft tissue attachments