SA Conditions of the Foot

Question 1

Causes of lameness localised to the foot in the dog and cat.

Answer 1

Joints:
- Dislocation
– metacarpophalangeal, metatarsophalangeal, interphalangeal.
- Inflammatory
– infection such as paronychia that can extend to the bone.
–> osteomyelitis.
- Musculotendinous
– tendon rupture or collateral ligament rupture –> dislocation.
Bones (GIFT):
- Growth plates – rarely cause problem.
- Inflammatory – osteomyelitis.
- Fractures – metacarpal / metatarsal bones and phalanges, sesamoids.
- Tumours – SCC, malignant melanoma, metastatic carcinoma (cats - lung digit syndrome).
Soft tissues
- Pads – corns, plasma cell pododermatitis, wound, FB,
- Interdigital – FB / grass awns / paronychia.

Question 2

CE, further investigations of lameness localised to foot.

Answer 2

Pads / interdigital area / nails / wounds (think tendons).
Imaging - radiography, CT for fractures, dislocations etc.

Question 3

Fractures…
1. Aetiology.
2. Signalment.
3. Clinical signs and Dx.
4. Tx.

Answer 3

1. Trauma.
2. Any.
3. Swelling/pain/lameness.
   Imaging - x-ray or CT.
4. Sx recommended if:
   - >2 bones affected.
   - fragments displaced.
   - base of MC/MT affected.
   - articular surface affected.
   - the small bones are pinned (intramedullary pinning or toggle pinning) or occasionally plated.
   If no Sx needed can heal with external coaptation (splinting).

Question 4

Sesamoid fractures.

Answer 4

Can fracture and cause lameness.
Tx = removal.
CT is the best imaging modality to see this.
Also see incidental fragmentation that does not cause lameness, particularly in rottweilers.

Question 5

Toe dislocation.

Answer 5

Large breed athletic dogs.
Rupture of collateral ligaments and joint capsule.
Tx:
- closed reduction and conservative (rest/bandage/short nail).
- open reduction and collateral ligament prosthesis.
- closed reduction and external skeletal fixation).

Question 6

Corns.

Answer 6

In sighthounds.
Focal area of hyperkeratinisation.
Aetiopathogenesis = focal pressure on pad seen due to little SC fat.
Clinical signs - painful pad, focal lesion – usually pad III/IV forelimbs but can affect any pad.
Tx = superficial digital flexor tenectomy.
Px = guarded for recurrence after corn removal, good following tenotomy.