Lateral-medial balance defined:
- "Balance" implies symmetry between the lateral and medial halves of the hoof.
- "Imbalance" implies asymmetry between the two halves.
- This definition recognizes that the medial wall should be slightly straighter than the lateral wall
Evaluating lateral-medial balance:
- Viewing the foot from the front:
- Compare the height of the hoof wall at the quarters.
- Compare the angle of the hoof wall at the quarters.
- The coronary band should be level to the ground.
- Viewing the foot from beneath (i.e. the bearing surface):
- Compare the medial and lateral halves, dividing the foot along the central sulcus of the frog.
- Compare the bars and height of the wall at the heels.
- Viewing the foot from the back - compare the height and angle of the heels.
A 14-yr-old sport horse used for dressage (training at 3rd level) had developed over the past several months a severe, bilateral lateral-medial imbalance, worse in the RF than in the LF. Previously, 18 months prior, during a Preventive Foot evaluation, the coronary bands were level, although the medial wall of the RF was more upright than the lateral wall. Hoof wall angles (angle of dorsal hoof wall in relation to bearing surface) and foot widths were similar between left and right feet and had not changed over the past 18 months. The horse's forelimb conformation was good with no obvious angular deviation in either limb. At the time of examination, the following measurements were recorded for wall height at the quarters:
|Right Front||Left Front|
|8.4 cm||7.1 cm||7.6 cm||8.1 cm|
Dorsopalmar radiographs illustrate the extent of the imbalance:
(Note: The white line overlying the pastern is wire taped to the coronary band.)
Currently, the horse is not lame and is working well. The owner is concerned that any radical changes might cause lameness.
Which Treatment Would You Choose?
- Trim the feet conservatively and simply use the shoe to support the medial quarter/heel?
- Trim the excess 1.3 cm (1/2 inch) of wall on the lateral quarter of the RF and the excess 0.5 cm (1/4 inch) of wall on the lateral quarter of the LF?
- Remove half of the excess at this shoeing and remove the remainder in 4 to 5 weeks?
The selected treatment plan was (#3 above) to remove only half of the excess wall at this shoeing and repeat the radiographs. Measurements of wall height at the quarters after trimming were as follows:
|Right Front||Left Front|
|7.5 cm||7.0 cm||7.6 cm||8.0 cm|
The medial lateral imbalance was completely corrected in 3 shoeings, with no lameness shown throughout this time.