Page 180 - Canine Lameness

152 12 Distal Limb Region

DISTAL LIMB REGION

(A) (B) (C) (D)

Figure 12.4 Normal radiographs of the hindpaw: (A) lateral; (B) dorsoplantar; and (C) dorsolateral
plantaro-medial oblique (DLPMO); and (D) dorsomedial plantaro-lateral oblique (DMPLO) view. (a) Dorsal
sesamoid; (b) metatarsal I; (c) sesamoid 2, and (d) sesamoid 7; metatarsals 2–5 are labeled with roman
numerals (II–V).

12.2.3 Function, Posture, and Carriage
The metacarpal and digital pads should all touch the contact surface. Additionally, the digits
should be slightly splayed, dorsally angled relative to the metacarpals, with digits III and IV ele-
vated above and extending forward relative to digits II and V. The dorsal surface between the distal
interphalangeal joint and the nail bed should be slightly concave. The claws (nails) should curve
downwards, but if appropriately worn or trimmed, the tips should not touch the contact surface
while standing, but rather be suspended slightly above it, ending square as well as caudally bev-
eled. The metacarpophalangeal and metatarsophalangeal joint angles have been measured using
three-dimensional videography (Nielsen et al. 2003); however, they are infrequently measured
objectively in the clinical setting. With increasing velocity, the digits splay slightly more, the pads
expand, and the claws rotate distally into the contact surface. Reported normal range of motion
angles for the carpus and tarsus are described in Chapter 5.

12.3 Arthritis

Osteoarthritis of the lower limb region is poorly described. The condition can involve any joint,
although the metacarpophalangeal joints IV and V have a higher incidence than those of II and III as
well as the metatarsophalangeal joints (Franklin et al. 2009). Individual or multiple joints may be