This segment also incorporates parts of the neurologic assessment.
It includes observing the horse being led from its stall, at rest; and in hand on a hard surface—backing up, walking and trotting straight lines and circles.
Results of front and hind ﬂexion tests and others, eg, hind retraction tests, are recorded.
A positive response to front fetlock and pastern ﬂexion, with no other signs of lameness or pathology, is found in sound horses and should not be used as a sole criterion for evidence of a problem.4,5 Positive results of hind ﬂexion tests, supporting the leg above the fetlock, are usually a source of concern.
The horse must be relaxed and go with its head free to move.
If this cannot be accomplished by horsemanship, 25 to 100 mg of xylazine or 5 to 10 mg of acetylpromazine can be used without masking lameness.
Very small walk circles are performed to evaluate neurologic function.
If possible, the horse is walked and trotted up and down hill normally and with the head elevated and also backed uphill.
Next is longing at all three gaits on soft, deep footing.
The horse is ridden in its normal competition balance.
Along with normal gaits, I like to observe a reinback, changing diagonals every 10 steps on a straight line and in both circles, small ﬁgure eights at the trot with an abrupt change of bend, extended trot, tight canter circles, ﬂying changes and galloping on both leads.
The heart and lungs are then ausculted.
Other movements can be observed.
The horse is not jumped unless it is requested by the buyer or there is a question that might be elucidated by jumping.
Generally a horse jumps away from a sore front leg and Proceedings of the Annual Convention of the AAEP 1999 Reprinted in the IVIS website with the permission of AAEP Close window to return to IVIS lands going at an angle rather than straight ahead.
Hind-leg lameness customarily causes it to jump toward the sore limb.
Jumping and dressage prepurchase examinations should focus on the front feet and pasterns, hocks, front and hind suspensory ligaments, axial skeleton, locomotor muscles, and stiﬂes.
Less commonly a source of problems, but also important, are the fetlock joints, front superﬁcial ﬂexor tendons, splints, bicipital bursae, and check ligaments.
The front legs and feet are examined.
The type and quality of shoeing is noted, as is shoe wear.
An example of the many factors the veterinarian must consider before reaching a conclusion is demonstrated by an oddly shaped or small foot.
In this case, the following factors are relevant: history of previous lameness; conformation that may relate to the foot; musculoskeletal pathology in the leg; shape and quality of the hoof; wear of the shoe or foot; shoeing; response to hoof testers and percussion; the ﬂight of the leg and the foot landing and breaking over; evidence of lameness (especially in small circles on hard going, preferably on a slight incline); other tests (such as toe elevation prior to trotting); radiographic ﬁndings; the veterinarian’s knowledge of the intended discipline; and consideration of the buyer’s circumstances, eg, quality of the farrier (a good farrier might be needed to maintain difficult feet), schooling surface, probable show schedule and show footing.
Slight differences in size and shape of the feet are common and not necessarily abnormal.
Some variation may result from the left handedness in most horses.
An upright foot (‘‘club foot’’) can be functional depending on radiographic changes and shoeing.
Foot lameness is usually more apparent on hard going and frequently accentuated by circling.
This ranges from a minor sole bruise to irreversible ‘‘navicular disease.’’ International regulations prohibit any sort of nerving.
Navicular disease includes several variants.
Radiographs do not always correlate with clinical signs, but certain lesions are cause for concern to the author, ie, multiple large lollipops, central radiolucent areas, radiolucencies that can be shown on the skyline view to break through the cortex, and large well-deﬁned cysts.
Many horses with mild navicular disease, if shod and managed well, are acceptable for pleasure riding and easy competition, but jumping big jumps is not compatible with navicular sensitivity.
Dressage riding surfaces are forgiving of foot problems, but a tendency to shorten stride is not a good thing in a dressage horse.
Corners, zig zags, extended trot, and tempo changes are movements in which navicular disease may degrade performance.
Hunters can compete with mild navicular disease provided that the gallop stride is naturally long and the going is forgiving.
Some horses with caudal hoof pain have a laminar tearing rather than an internal foot problem.
Pedal osteitis and deep bruising may sometimes reside in the subchondral bone of the third phalanx (P-3).
Ossiﬁcation of the collateral carti- lages (sidebones) is frequent, especially in horses with draft blood.
It is rarely associated with lameness; nor do asymmetrical ossiﬁcations relate to uneven foot loading.6,7 However, navicular spurs can result from extremely uneven hoof loading.
Laminitis/founder have so many variables that each case must be evaluated on its own merit.
The front and hind proximal interphalangeal joints frequently show slight radiographic remodeling of the dorsoproximal articulation of P-2 as well as changes of shape of the hind pastern bones.
This seems to be more frequent in warmbloods.
Although these changes are usually of no clinical signiﬁcance, proximal interphalangeal degenerative joint disease (DJD) develops occasionally.
Distal interphalangeal DJD that is demonstrated radiographically, is quite serious.
Short, upright pasterns predispose to interphalangeal joint disease.
A small, smooth, radio-opaque density at the apex of the extensor process is, by itself, usually benign.
Suspensory apparatus disorders include high suspensory disease (HSD), suspensory body and branch desmitis, lesions of the sesamoid bone, and distal sesamoidian ligament injuries.
Front-leg HSD— which the author suggests is primarily an attachment desmopathy with or without signiﬁcant desmitis—is very common in sport horses.
Horses with mild lameness from front-leg HSD, surprisingly, can compete satisfactorily over big fences, frequently with little or no increase in lameness.
Once the lameness has resolved, about 20% of jumpers have a recurrence.
It is a late-bearing lameness that is most easily observed with the horse circling at the trot in deep going, with the affected leg on the outside of the circle, or trotting down a slight grade.
Work tends to decrease the lameness.8 Proximal suspensory ligament involvement of the hind leg behaves clinically and therapeutically quite differently from front-leg HSD, and it is one of the most serious and difficult conditions with which to contend.
Chronicity and recurrence are frequent and are exacerbated by collection.
This lameness is characterized by limited protraction at the trot and may ﬁrst be evident in the extended trot, especially when the horse is turning.
Unlike front HSD, in hind HSD the lameness usually increases during a riding session and seriously detracts from jumping and dressage.
Grand Prix dressage horses may have to be retired.
This condition tends to be associated with a straight hock, but it is found in other conformations.
Sue Dyson has suggested that the lameness is the result of a chronic neuritis,a which would explain the clinical signs better than a desmitis.9 Front or hind suspensory body and branch lesions are frequent in athletic horses and are the most common cause of athletic retirement in jumpers.
Ultrasonographic evidence of ﬁbrosis between the hind branches connotes a poor prognosis.9 Stretching of the suspensory ligament, which permits greater pastern translation, can lead to a AAEP PROCEEDINGS 9 Vol. 45 / 1999 7 Proceedings of the Annual Convention of the AAEP 1999 Reprinted in the IVIS website with the permission of AAEP Close window to return to IVIS IN DEPTH: PURCHASE EXAMINATION progressive debility and loss of athletic use.
Straight hocks and sloping pasterns are associated with branch and body stretching.
While this usually develops in old mares, it can affect horses in their prime as well.
Radiographic evidence of sesamodititis does not seem to inﬂuence soundness.
Sesamoid fractures are rare, except in ex-racehorses, but can be signiﬁcant.
Only severe radiographic sesamoiditis is usually associated with lameness.
Fetlock DJD is more prevalent in warmbloods than in Thoroughbreds (except for racehorses) and can involve the hind joints as well.
Small, smooth ‘‘chips’’ associated with dorsoproximal P-1 are usually unimportant if the joint is otherwise not remarkable.
Larger and multiple lesions are cause for concern.
Even without obvious lameness, metatarsophalangeal joint disease can affect jumping.
Healed superﬁcial digital ﬂexor tendinitis (bowed tendon) is usually well tolerated by sport horses, except for elite jumpers competing over large fences (World Championship, Olympic Games).
In the 1960s and 1970s, when the jumps were considerably larger, the incidence of bows and rebows approached that of race horses.
However, most affected horses were able to compete again.
Palpable, nonsensitive thickening of the distal check ligament is occasionally felt.
Usually this has not caused past lameness, nor is it necessarily a cause for concern.
Digital sheath enlargement (‘‘windgalls’’) usually is reasonably symmetrical and benign.
Extreme distention also involving the distal pouch can result from chronic inﬂammation.
If synovial proliferation and adhesions develop, they may cause lameness that is difficult to treat.
Palmar annular ligament constriction usually is multifactorial and may include thickening of the subcutaneous tissue, annular ligament thickening, chronic synovitis, superﬁcial or deep digital tendinitis or involvement of the encircling ring of the superﬁcial tendon.
Although these structures all can be involved, proliferative synovitis is the most frequent.
Thickening or stretching of the digital annular ligaments has similar causes, and thickening of distal ligament is an indication of deep digital ﬂexor (DDF) tendinitis.10 The most frequent location for pathologic DDF changes, including longitudinal tears, in both front and hind legs is within the digital sheath.
Therefore, healing is slow and there is a tendency to develop adhesions, which are serious.11 An ultrasound examination is necessary for accurate diagnosis in annular ligament and digital sheath conditions.
Splints are customary but usually of no clinical signiﬁcance.
Some, especially lateral splints, heal slowly and can occasion protracted lameness.
A large splint detracts from a conformation hunter.
Axial skeletal soundness is very important for jumping and dressage but not as important in hunters.
Mild back soreness may be acceptable for low-level jumpers and equitation horses, because limitation of back movement can make them easier 8 1999 9 Vol. 45 9 AAEP PROCEEDINGS for less skilled riders to sit on in the air.
With higher jumps, sore backs may manifest by ﬂat jumping, inadequate use of the hind end, inability to shorten to oxers, bucking and anxiety leading to disobedience.
Dressage horses with thoracolumbar pain have difficulty with zig zags, circles and piaffe.
The universal complaint is that a horse will not ‘‘come through,’’ ie, educated riders feel a lack of connection between the forehand and hindquarters.12 I examine the temporomanidublar joints, neck, forehand muscles, withers and back, including the area around the tuber sacrale, sacrum, pelvis, gluteal and hamstring muscles and the tail.
The neck is manipulated to evaluate ﬂexibility and pain.
Cervical muscle soreness is the most common condition, but facet joint arthritis, equine protozoal myeloencephalitis (EPM), vertebral stenosis and spinal root nerve impingement13 all can cause neck pain and in some cases changes in cutaneous sensation.
Healed fractured withers usually are of little signiﬁcance except for saddle ﬁt.
Back ﬂexibility and pain are evaluated visually by palpation of both the muscles and the vertebral processes and by incorporation of various maneuvers.
An effort is made to distinguish between muscular and skeletal pain.
Radiography (and nuclear scans) can be helpful if the latter is suspected.
Palpable pain in the lumbosacral space and lateral to the tuber sacrale (but not of the tubera) may indicate ‘‘sacroiliac’’ soreness.
It will cause reduced power pushing off and may also be evidenced by difficulty resisting with the hind legs in abrupt halts.
In more severe cases it causes mild lameness.
If the condition is chronic, it tends to recur with increased work and will degrade jumping and dressage.
Gluteal and hamstring soreness are common in athletic horses and, although usually transient, can be chronic.
This is especially true of gluteal myositis/tendinitis, ﬁrst described by Dr.
Edwin Churchill.14 Even without demonstrable lameness, gluteal soreness is likely to degrade jumping and extreme collection signiﬁcantly.
Coincident with examination of the axial skeleton, acupuncture points relative to the musculoskeletal system are palpated.
A healed, fractured tuber coxae (‘‘knocked down hip’’) usually has no effect.
Mechanical lameness results infrequently.
This does not usually impair jumping but may make the jog at international shows a sticking point.
Dressage judging penalizes any gait unevenness.
Inﬂammation of the distal intertarsal and tarsometatarsal joints affects more than 50% of all jumpers and grand prix dressage horses and requires treatment for maintenance of peak performance.
Usually the condition is bilateral but not symmetrical.
A combination of shoeing, management and medication generally is successful.
Many horses will require intra-articular injections.
Defective ﬂying changes are one of the ﬁrst signs of a problem.
The correlation between radiographic appearance Proceedings of the Annual Convention of the AAEP 1999
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