Taken from Taber’s Medical Dictionary a trigger point or trigger zone is “an area of tissue that is tender when compressed and may give rise to referred pain and tenderness”. An active trigger point is ” A trigger point that is painful when the involved muscle is at rest.
Palpation will reproduce the patient’s symptoms”. Latent trigger points are ” Trigger points that are not symptomatic when the involved muscle is at rest, but produce pain during palpation. Range of motion and strength may also be affected.”
Identifying trigger points in the horse or dog is done through palpation of the tissues. The tissue that contains the trigger point will be hardened and there will be a taut band
of fibre present. Sometimes this hardened tissue is identified as a knot but muscles can not be tied in knots so a more accurate description would be an area of hardened or swollen tissue that may be hotter than the surrounding tissue though if chronic could be cold.