The coronary grove is situated in the coronary body which is a half round fibro-cartilaginous
roll, this gives some flexibility and also absorbs some concussive forces in the
coronary band area, it also reduces in thickness towards the heels as does the thickness
The coronary corium is covered in long papillae which grow distally. This corium
supplies the papillae with nutrition so the horn can be produced. From around the
base of the papillae tubular horn is made which grow distally to the grounds surface.
Figure 1: Showing the coronary cushion, perioplic corium and the long papillae.
These grow distally in a multi layered, alternating spiral structure. This structure
gives great strength, good shock absorbency and resists wear reasonably well.
Inter tubular horn
This grows from the germative layer of the epidermis within the coronary corium from
the hollows between the papillae; it acts like cement and totally encases the tubular
Intra tubular horn
This grows from the tip of the papillae; they act as moisture conveyers maintaining
the flexibility of the horn.
The horn tubules are spaced further apart on the more internal area of the hoof wall
becoming more closely packed towards the external part of the wall. This is due to
the way the hoof transfers weight. Tubular horn resists compressive forces effectively
whilst inter tubular horn is more effective dealing with tensile forces.
Figure 2: Cross section of the dorsal wall including the laminae and distal phalanx.
There are 2 types of laminae: Primary and Secondary.
There are 2 types of primary laminae:
1. Dermal (sensitive) laminae - this is produced from the laminar corium and surrounds
the parietal surface of the distal phalanx to which it is attached to via a modified
periosteum. The sensitive laminae also contain a network of blood vessels which supply
the insensitive laminae.
2. Epidermal (insensitive) laminae - this is produced from the coronary corium and
grow distally with and at the same rate as the horny wall, it detaches and reattaches
to the dermal laminae in a ratchet like motion as the horn grows down.
There are about 500 to 600 primary laminae leaves which each have 100 to 200 secondary
laminae leaves interlocking both the dermal and epidermal laminae together. This
is known as interdigitation between the two laminae.
Blood travels down the limb around the circumflex artery at the distal phalanx, up
the sensitive laminae where it is fed to the laminae corium and the insensitive laminae.
The blood continues proximally to the coronary band where it is fed to the papillae
which produce the horn cells.
Figure 3:The hoof wall from a shire horse. Shire horses are well known for the quantity
and quality of hoof they produce.
Growth of the horny wall
Paul Conroy BSc(Hons) AWCF &
Sam Ratcliffe Dip WCF
The wall grows from the dermis of the coronary corium, which is situated in the coronary
grove on the internal proximal boarder of the hoof wall.