Orientation of the horse’s spine in a way that is not consistent with its trajectory (directional path of movement).
E
Eccentric Muscle Action: Relaxation or lengthening of muscle fibers.
Etiology: Cause or origin.
Excursion: Excessive up-and-down movement of one or more of the horse’s body parts.
Extrinsic: Originating from outside of the horse’s body or respective body part.
F
Fascia: A thin sheath of fibrous tissue encasing muscle or other organ.
Fibrocartilagenous Joint: Formed via the presence of an intervertebral disc.
Fibro-Osseous Junction: The site at which a ligament or tendon attaches to bone.
Fibrotic Myopathy: Pathologic condition characterized by the presence of scar (or fibrotic) tissue within one or more muscle bellies. Scar tissue can deleteriously affect the pliability of the muscle(s) within which it develops, thereby having the potential to precipitate biomechanical lameness.
Fibrotic Tissue/Fibrosis: Scarring that typically forms pursuant to an injury and local tissue damage.
Flexor Tendonitis: Inflammation of the superficial and/or deep digital flexor tendons.
Flexural Deformity: Excessive bending of one or more joints in response to disproportionate tension of the flexor apparatus.
Flight Path: The track of a limb or foot as it advances through the air during the non weight-bearing phase of the stride.
Flight Phase of Stride: The phase of a horse’s stride during which the respective limb is airborne (not in contact with the ground surface).
Forging: Striking of a forelimb with the ipsilateral hind limb (on the same side of the horse). Usually occurs as the toe of the hind foot strikes the heel of the ipsilateral forefoot at the trot. Also known as overreaching.
Fracture: A break or fragmentation. “Blunt trauma resulted in fracture of the underlying bone.”
Fusion: The coalescence of two or more structures to form a single entity.
G
Gateado: A smooth and supple quality possessed by superior-moving Peruvian Paso horses.
Greater Trochanteric Bursitis: Inflammation of the greater trochanteric bursa, which is a synovial sac that lubricates the middle gluteal muscle tendon as it courses over the greater trochanter of the femur just outside of the hip joint. This condition is often referred to as whorlbone in horses.
Ground Reaction Force (GRF): The force exerted by the ground surface on a horse’s limb that is in contact with it. Vertical (up-and-down), transverse (side-to-side), and sagittal (front-to-back) ground reaction forces are experienced by each limb during the latter’s respective stance phase of the stride.
H
Hyperflexion: Flexion of a joint beyond normal or expected limits.
Hypermetric: Movement (such as flexion of the limbs) beyond normal limits.
Hypoflexion: Flexion of a joint short of normal or expected limits.
Hypometric: Movement (such as flexion of the limbs) shy of normal limits.
I
Innervation: Nerve supply.
Interference: A lateral gait deficit in which one foot contacts the inside of the opposing limb during flight. This is most commonly observed in horses that wing-in or plait, due to the close proximity of contralateral limbs during this activity. Also known as brushing.
Inter-: Between.
Intermittency: Alternately appearing and disappearing.
Intermittent Upward Fixation of the Patella (IUPF): A condition characterized by inadvertent engagement (or locking) of the patella over the medial trochlear ridge of the femur (an action epitomizing the primary component of the hind stay apparatus).
Intermuscular: Between muscle bellies.
Interphalangeal: Between two phalanges.
The horse has three phalanges in each limb: the first phalanx (also known as the long pastern bone or P1), the second phalanx (also known as the short pastern bone or P2), and the third phalanx (also known as the coffin bone, pedal bone, or P3). There are two interphalangeal spaces: one between P1 and P2 and one between P2 and P3.
Intra-: Within.
Intramuscular: Within a single muscle belly.
Intrinsic: Originating from within the horse’s body or respective body part.
Ipsilateral: Located on the same side of the horse. “The right front limb is ipsilateral to the right hind limb.”
J
Joint: A point of articulation between two or more bones. Joints serve to absorb the force of impact, transfer the force via cartilage to bone, and to allow a variable degree of movement between bones.
K
Kinematics: The geometry of movement.
Kinesiology: The science of movement.
Kinetics: Forces that cause movement.
Kyphosis: Excessive ventroflexion of the spine, often referred to as a roached back.
L
Laminitis: Inflammation of the (laminar) tissues that bond the horse’s hoof to the underlying (pedal) bone. Laminitis is often bilateral and more commonly associated with the horse’s forelimbs.
Lateral: Away from the median plane. “When you look at a horse’s left
