Foreign body that does not penetrate the hoof capsule

Hoof abscess

Acute, severe lameness is possible; the digital artery pulse is increased and the hoof feels warmer, possibly with diffuse swelling in the distal part of the leg. If an abscess has developed as a result of a misdirected nail during shoeing, the entry site will be underneath the horseshoe. A hoof abscess may result from a penetrating foreign body which was missed in the acute stage (and which had not remained lodged in the hoof).

Further reading: Chapter 'Hoof abscess'

Bruised sole

Acute, severe lameness, but with no visible entry hole or damage to the horn of the sole. A radiograph reveals nothing of note.

Further reading: Chapter 'Bruised sole & Corns'

Corns

No puncture channel is detectable. The horn of the sole shows local discoloration and, in some cases, is of poor quality. Occasionally, there may be a discharge of old, dark blood from a haematoma, or even a discharge of pus. In general, the lameness develops gradually.

Further reading: Chapter 'Bruised sole & Corns'