Page 664 - Adams and Stashak's Lameness in Horses, 7th Edition

630 Chapter 5

In older horses, a caudal application of a plate using
the tension band principle is necessary. 12,18,19,57 A con-
VetBooks.ir limbs showed that DCP application was more biome-
trolled study of different repair types in adult cadaver
chanically sound than pins and wires. Plates are
33
applied to the caudal aspect of the olecranon and ulna
to counteract the tension of the triceps brachii muscle
(Figure 5.37). The plate may be contoured over the top
of the olecranon if the fracture is proximally located.
Depending upon the size of the horse, a narrow or wide
DCP can be applied; a broad DCP is applied in horses
greater than 500 kg. More recently the LCP has been
65
used in repairs of the olecranon and may be indicated if
possible. 37,47 In most adult horses the 4.5‐mm‐narrow
LCP is likely to be adequate.

Prognosis
The prognosis for conservative management of non-
displaced fractures and nonarticular fracture types I and
IV of the ulna is considered good. Nondisplaced artic-
92
ular fractures, especially the type VI fracture, also
respond well to conservative treatment. One retrospec-
tive study reported 70% of affected horses becoming
sound. 92
The prognosis for internal fixation of displaced types
III, IV, V, and VI is also considered to be good. 19,21,24
Internal fixation of type I and II fractures in younger
foals has a good prognosis when a hook plate is used,
63
with 7 of 10 foals becoming athletes. Type II fractures
Figure 5.36. Two 4.5‐mm cortical screws with washers and in young horses also do very well when repaired with
figure‐8 wires used to create a tension band for a type I ulnar 81
fracture. Source: Courtesy of Dr. Gary Baxter. DCP, with 16 out of 24 horses returning to athleticism.
In another study of pins and tension band wiring, 13 of
22 horses were reported to be athletically sound, and 18
fractures were considered to be repaired successfully.
61
In a recent prospective study using LCP in 16 horses
with 18 fractures, complete fracture healing was
achieved in 13 horses. Twelve fractures were type II and
six type IV. Post‐discharge complications of implant
infection and lameness were resolved with implant
removal. 37

Luxation and Subluxation of the Elbow Joint
Subluxation or luxation of the radiohumeral joint
with or without a concomitant fracture has been
reported, although it is an uncommon injury. 17,42,71,73,82
Subluxation commonly occurs with rupture or partial
tear of the medial collateral ligament. Complete luxa-
76
tions often occur in conjunction with a fracture 46,82 ,
but luxation without fracture has also been reported
(Figure 5.38). 17,42

Etiology
Severe, forceful limb abduction such as getting a leg
caught in a fence is often associated with subluxations
of the elbow, whereas severe falls have been reported to
cause complete luxations. 17

Figure 5.37. Type III ulnar fracture repaired with a narrow DCP Clinical Signs
applied to the caudal aspect of the ulna. The fracture was in an
older horse; therefore, the distal screws penetrated the radius. Swelling in the axilla of the affected side and a non‐
Source: Courtesy of Dr. Katie Seabaugh. weight‐bearing lameness are the commonly reported