Many of you will know my previous work on headcollar use and its potential dangers (if not, please follow this link to see more). Many headcollars will not break if a horse pulls back or gets caught in them, and this can lead to injury or worse. This is especially true for nylon or good-quality leather headcollars. The image below is of a horse that broke its neck and died when its foot got caught in its headcollar.


The effect of loading up to 300kg on the pressure under a nylon headcollar.

Effective poll pressure under a nylon headcollar with increasing loading
Headcollar didn’t break
Peak pressure of 1278 kPa – 50x higher than pressures thought to cause tissue damage
Typical pressures under saddles are 5-50kPa
Peak pressures above 31kPa believed to cause pain and tissue damage Nyikos S, von Rechenberg B, Werner D, et al.
Measurements
of saddle pressure in conjunction with back problems in horses. Pferdeheilkunde Equine Med 2005; 21(3): 187–198.
In a preliminary study of the pressure on the poll under a synthetic headcollar headpiece in a horse being led at walk and trot,
peak pressures of 50 kPa at walk and 60 kPa at trot were recorded (Godoy & Marlin, unpublished observations).
High pressure on the poll can damage…
- Auricular abductor muscles
- Auricular levitator muscles
- Scutularis muscles
- Complexus muscles
- Splenius muscles
- Rhomboid muscles
- As well as damage to nerves and blood vessels
For these reasons, we recommend using a safety headcollar in almost all situations.