The influence of head and neck position on kinematics of the back in riding horses at the walk and trot.
BACKGROUND
A common opinion among riders and in the literature is that the positioning of the head and neck influences the back of the horse, but this has not yet been measured objectively.


OBJECTIVE
To evaluate the effect of head and neck position on the kinematics of the back in riding horses.


METHODS
Eight Warmblood riding horses in regular work were studied on a treadmill at walk and trot with the head and neck in 3 different predetermined positions achieved by side reins attached to the bit and to an anticast roller. The 3-dimensional movement of the thoracolumbar spine was measured from the position of skin-fixed markers recorded by infrared videocameras.


RESULTS
Head and neck position influenced the movements of the back, especially at the walk. When the head was fixed in a high position at the walk, the flexion-extension movement and lateral bending of the lumbar back, as well as the axial rotation, were significantly reduced when compared to movements with the head free or in a low position. At walk, head and neck position also significantly influenced stride length, which was shortest with the head in a high position. At trot, the stride length was independent of head position.


CONCLUSIONS
Restricting and restraining the position and movement of the head and neck alters the movement of the back and stride characteristics. With the head and neck in a high position stride length and flexion and extension of the caudal back were significantly reduced.


CONCLUSIONS
Use of side reins in training and rehabilitation programmes should be used with an understanding of the possible effects on the horse's back.
Rhodin
M
M
Department of Anatomy, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden.
Johnston
C
C
Holm
K Roethlisberger
KR
Wennerstrand
J
J
Drevemo
S
S
D000054:Acceleration; D000818:Animals; D001415:Back / Q000502:physiology*; D001696:Biomechanical Phenomena; D005080:Exercise Test / Q000662:veterinary; D005260:Female; D005684:Gait / Q000502:physiology*; D006257:Head / Q000502:physiology*; D006736:Horses / Q000502:physiology*; D008297:Male; D009068:Movement / Q000502:physiology; D009333:Neck / Q000502:physiology*; D016138:Walking / Q000502:physiology