Lameness

While lameness in the horse is generally the domain of the veterinarian it is not unusual for a farrier to be asked to give an opinion on an individual. On occasion you will have to make an assessment of a horse prior to shoeing, if there is a question of unsoundness . Having a good understanding of the most common sites of lameness in the fore and hind limbs and how lameness may exhibit will help you to arrive at a useful conclusion.

Terms Blemish: Observable abnormality, does not interfere with the intended use of the horse. Cosmetic Sound: Excellent health. Unsound: Deviation from the norm, may or may not interfere with the intended use, may or may not predispose to, or be a pathological condition. Lame: Deviation from the ideal, stance or gait, due to pain or mechanical dysfunction. A sign of a pathological condition. Not sound.

Lesion: Specific damage or pathology causing pain or discomfort Lesion: Specific damage or pathology causing pain or discomfort. Lameness may result from a lesion. Acute: Short term, severe, characterized by pain, heat, swelling. Chronic: Long standing, less severe than acute, may follow acute. Often recurring, less obvious than acute. Congenital condition: Acquired during development in the womb, includes hereditary. Hereditary condition: Acquired at conception from genetic material of parents.

Types of lameness Supporting leg lameness: The period of time weight is borne on the supporting, affected, leg is shorter than normal. Or absent in severe cases. Swinging leg lameness: Alterations in the phase of flight, shortening, as well as changes in the arc of flight. Mixed lameness: Combination of the above types. Difficulty advancing the affected limb and weight bearing.

Guidelines Swinging leg lameness usually located high up and are accentuated when the horse is circled with the affected leg on the outside. Supporting leg lameness usually located from the carpus and tarsus on down the leg. Accentuated when the affected leg is placed on the inside of the circle.

Analysis of motion Supporting leg lameness. The phase of contact is shortened. Swinging leg lameness. In mild cases the first half of the phase of flight is normal while the second half is shortened or absent.

Obtain an accurate history Lameness exam Obtain an accurate history When first went lame, duration, progression of lameness. Circumstances that may be the cause. Character of the lameness, continuous, on-off, warm out of it, warm into it. Present use of the horse, past use. Characteristics of lameness when in use, way of going, terrain a factor.

Visual Exam Stand back and OBSERVE Temperament Conformation Physical condition Obvious deformities

Fore Limb Lameness Horse will nod the head downward when weight is borne by the sound limb. Horse will nod the head upward when weight is borne by the lame limb. Observe the horse from in front. If the examiner moves his/her head in time with the horse that may assist on leg selection. Observation from the side will show alteration of flight pattern of the limb

Lameness of the Hind Limb The hip will drop on the sound limb, while the lame limb and hip will be carried higher. Observe the horse from behind to see this effect. Observing the horse from the side will show alterations of limb/hoof flight.

Observing the horse at the trot will locate the lame leg Observing the horse at the trot will locate the lame leg. The next step is to locate the site of the lameness. To do this the examiner will employ the following. Palpate and use passive movements. Use a hoof pick and hoof knife. Use hoof testers Compare leg pairs

General conditions Disease of the dorsal area of the hoof will cause the hoof to land heel first and shorten the breakover phase of the stride. e.g. Laminitis Disease of the palmar/plantar area of the hoof will cause a toe landing stance. e.g. Navicular disease. Shoulder lameness is rare.

General guidelines The majority of lameness conditions are found from the carpus/tarsus to the foot. If lameness is severe check for an abscess or foreign body in the hoof. Do not be misled by the presence of another blemish or healed lesion. Obtain an accurate history. Use a systematic routine

Obel classification of lameness Difficult to observe, not consistently apparent. Difficult to observe at walk or trot in straight line, consistently apparent under special circumstances. Consistently apparent at all circumstances. Obvious lameness, head nodding, shortened stride. Minimal weight bearing, motion or rest, inability to move.

Useful Information Resting pulse rate 44 beats per minute Temperature 99 – 101F. 38C Feces Every 3 hours Urine Every 6 hours