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366 Cards in this Set
- Front
- Back
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With a forelimb lameness what sort of gait abnormalities would be seen?
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The horse throws its weight upwards when the lame leg is moved forward and catches the weight on the sound limb. - "Head goes down on sound"
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What happens with a hind limb lameness?
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The hip rises when the lame leg is used
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Which is the best gait for lameness evaluation?
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Trot
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In a subtle lameness which joint does not extend (drop) fully?
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The fetlock
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Most lameness involves which limbs?
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The forelimbs
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What tool can you use to examine the foot?
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Hoof testers
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What tests will temporarily make the lameness worse and help identify it?
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Flexion tests
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TRUE OR FALSE
Back soreness is rare in rear limb lameness |
FALSE
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What is the preferred local anaesthetic to use for nerve blocks in the horse?
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Mepivicaine - less irritating and lasts longer
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What must you always remember with regional nerve blocks?
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To start at the most distal point
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What block numbs the palmer 1/3 of the foot and sole?
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Palmer digital
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What are does a foot block cover?
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When combined with the PDN block - all structures within the hoof
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Which block numbs all structures distal to the mid pastern including the pastern joint?
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Abaxial sesamoid block
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Where are the injections made in a low four point block?
Where does it block? |
Level with the distal end of metacarpal/tarsal 2 and 4
It blocks all areas distal to injection site |
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What is it called when the injections are made at the proximal level of the matacarpus?
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High 4 point block
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What is the difference between high and low blocks in the rear limbs?
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A 6 block is used instead of 4
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Why is an injection into the navicular bursa not very practical?
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Asepsis is difficult and you need to be guided in radiographically
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What block can you perform instead of a navicular bursa?
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A Distal interphalangeal (coffin) joint
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What is thrush?
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A degenerative condition of the frog characterised by a black necrotic smelly material
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What is the etiology of thrush?
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Filthy conditions
Failure to clean the foot properly Lack of frog pressure interferes with natural cleaning |
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What are the clinical signs?
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Discharge
Frog may be undermined Sometimes involves sensitive tissue and causes lameness |
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What can be used to treat it?
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Coppertox, formalin, hydrogen peroxide
If the frog is involved then trim off the tissue and apply mild disinfectants as a wet dressing and bandage daily |
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What is a corn?
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Bruising of the sole at the angle of the wall and the bar. Usually in the front foot
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What are the 3 classifications of corns?
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Dry - reddened sole
Moist - serum under sole Suppurating - secondary infection |
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What is the most common reason for corns?
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Improper shoeing or leaving the shoes on for too long
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How can it be managed?
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Remove offending shoe - put on a bar shoe
Trim the sole Provide drainage if it is infected Rest and NSAIDs Can be a long recovery if severe |
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What is a bruised sole?
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Same as corn except any area of the sole except the angle of the wall and bar
As a result of rough terrain etc. Same tx as corns |
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What is an inflammatory condition involving the third phalanx resulting in a loss of density in P3?
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Pedal osteitis
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What sort of things can cause it?
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Severe repeated sole bruising
Laminitis Chronic subsolar abscess |
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Which feet are usually affected and why?
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Front feet as they bear more weight. Usually bilateral, short choppy gait
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How can it be treated?
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Wide web shoe +/- pads
Rest from forced exercise but stable rest is not necessary or desired |
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What is the prognosis?
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Guarded, foot protection for up to a year might be needed
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An abscess under the sole of the foot which is the most common cause of lameness is what?
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A subsolar abscess
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What will happen if the abscess is not drained?
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When close to the white line it will drain at the coronary band "gravel"
When at or near the frog it drains at the heel |
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How is it diagnosed?
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Usually severe lameness
Increased reaction to hoof testers, tapping on the wall of the hoof Increased pulse in digital arteries |
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How can it be treated?
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Thoroughly pare out all discoloured areas of sole until find pus
Ventral drainage is most important make a hole at least 2.5cm and maintain drainage until sole is healthy ~ 1wk |
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What drugs will you use?
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Abx not usually necessary in adults but suggested in foals to prevent osteomyelitis
Tetanus prophylaxis |
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How is tetanus prophylaxis usually given?
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If no hx of tetanus toxiod administration and horse is under 2yrs give toxoid and antitoxoid
If horse has had tetanus toxoid or is older just give another dose of toxoid |
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What condition is caused by improper foot wear or trimming?
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Sheared heels or wry heels
A marked difference in the length of the hoof wall at the heels resulting in variation of pressure applies to each side of the foot |
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When would you not bother to treat?
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If the horse isn't lame, just shoe the horse don't try to correct
If lame, trim the foot to balance the weight and put on a bar shoe |
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What is it called when the heels are closer together than normal?
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Contracted heels
- the result of the animal not bearing enough weight on the heels due to pain, long feet, casts |
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How can this be managed?
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By proper shoeing and trimming, slipper shoes, wide shoes
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What makes up the navicular apparatus?
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Navicular bone
Collateral ligaments of the navicular bone Distal sesmoidean ligament (impar lig.) Navicular bursa DDF tendon Distal annular ligament |
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At what age is navicular disease most common?
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Age 4-9 yrs
Most common in quarter horses and in geldings |
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What could be the etiology?
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Abnormal mechanical forces
- hard work, small feet, upright pasterns and shoulders Circulatory disturbances not now thought to be that significant |
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What are the clinical signs of navicular disease?
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Usually front foot lameness
Usually bilateral with one foot worse Short choppy gait Horse has sore shoulders (sternomandibularis muscle myositis) Foot worn at toe and horse "points" foot and they tend to stumble |
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How is it confirmed?
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If the lameness if reduced with a distal interphalangeal joint block and a palmer digital block
50% will not have radiographic changes Changes are a lollipop appearance to vascular channels on distal border of navicular bone, spurs or periosteal proliferation |
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How can it be managed?
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Most horses will have pasture soundness
Have foot trimmed/shod to maximise heel expansion, consider egg bar shoes |
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What medical therapy is available for navicular disease?
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NSAIDs
Isoxsuprine hydrochoride - increases blood flow Intra-articular corticosteroid therapy into coffin joint |
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Is there any surgical therapy?
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Palmar digital neurectomy - need to keep leg in bandages and strict rest for at least a month to prevent neuroma formation
Desmotomy of suspensory ligaments of navivular bone |
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What is the prognosis?
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It cannot be cured, surgery just makes sure that the horse doesn't feel the pain, horse is more inclined to stumble
Many animals are fine for several years follwoing treatment |
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What are the 4 types of fracture of the navicular bone?
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Avulsion
Frontal Comminuted Simple body |
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Does a fractured navicular bone present with clinical signs?
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Yes - acute severe weight bearing lameness
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What can be confusing in a radiograph of the navicular bone?
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If it is bipartite (2 ossification centres)
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What are the two ways of dealing with a navicular fracture?
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Conservative - apply an elevated bar shoe and rest up to 1yr
Surgical - insertion of lag screw - need special training and 6-8mths rest |
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How should acute laminitis be handled?
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AS AN EMERGENCY!
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What are the clinical signs of chronic laminitis?
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Marked evidence of foot pain, reluctance to move and turn, increased digital pulse, resists picking up the foot and marked resistance to hoof testers/foot tapping
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How can it be managed?
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Judicious use of NSAIDs
Maintain normal blood pressure Comfortable stall with soft bedding Not excessive feed |
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What surgical options are there?
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Maintain frog support - heart bar shoes, rail shoes
Removal of dorsal hoof wall DDF tenotomy - reduces pull on lamina Inferiour check ligament desmotomy |
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Where can the DDF tenotomy be performed without opening up the tendon sheath?
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At the mid metacarpus - any lower and the sheath has to be opened and the animal recumbant
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What is the prognosis?
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Always guarded for chronic laminitis
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What kinds of hoof cracks can a horse get?
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Toe, quarter, heel and transverse
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Which cracks cause lameness?
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Deep cracks involving the sensitive lamina
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How can cracks be managed?
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Superficial
Cut a horizontal groove that extends to the white line slightly proximal to the crack Drill a hole down to white line at top of crack Cross nailing Perforating cracks Clean out thoroughly, seal with hoof acrylic, metal or leather patch Put on a bar shoe and trim the hoof so no weight bearing on the crack itself |
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What is a keratoma?
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A tumourous mass that develops in the dorsal aspect of the hoof wall
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What are the clinical signs?
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Bulging of the hoof wall beginning at the coronary band, usually not painful until it grows big enough to put pressure on the lamina
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What are keratomas occasionally associated with?
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The development of conical plugs of abnormal horn extending upward from the sole surface
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What is the best way to manage it?
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Remove the hoof wall over the keratoma and debride to completely remove all abnormal tissue
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How do you look after the wound?
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Apply a bar shoe with clips to stabilize hoof wall
Maintain under bandage until wound becomes healthy Reset shoe every 6 weeks until hoof grows down to floor |
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What is a common cause of and infection in the navicular bursa?
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Puncture wounds through or close to the frog
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When should you start thinking that a horse might have an infection?
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If the animal is still significantly lame after drainage and treatment for a subsolar abscess
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How can you manage a navicular bursa infection?
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It needs to be flushed!
Cut down through the frog and DDF tendon Or can now use arthroscopic guidance - better Px |
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What are the types of fractures that can occur in the 3rd phalanx?
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1. Abaxial fracture w/o joint
2. Abaxial fracture with joint 3. Axial fractures with joint 4. Fractures of extensor process 5. Multifragment with joint 6. Solar margin fractures |
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How can these fractures occur?
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Acute trauma - kicking a hard structure
Excessive hard or fast work |
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What is the method of diagnosis?
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Usually acute lameness = sole abscess. If no response after a few days of soaking take some radiographs
It is normally easier to see fracture lines a few days after |
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What are some of the ways it can be managed?
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i) Fragment removal (type 4)
ii) Stabilisation with cast (1&2) iii) Bar shoe w/ clips and 9mths stall rest (type 3 <3yrs) iv) Compression screw (type 3 >3yrs) v) Stall rest for 4mths (type 6) vi) PD neurectomy on side of fx (type 1) vii) In foals stall rest, attach wooden block to foot |
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With the exception of type 5 at what age does the prognosis of these fractures go from good to guarded?
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At 3yrs of age - after this it is unlikely that older animals will return to competition
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A type 4 fracture (involving the extensor process) requires different management, what can be done?
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Small chips can be removed with an arthroscope
Large chips can either be left alone (run risk of low ring bone) or they can be stabilised with a screw |
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Why is the prognosis guarded if the fragment is large and must be stabilised?
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Limited room and access to the area means that only one screw can be placed. If stabilisation isn't complete there is a good chance low ring bone will occur
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By what other name is Periostitis of the Extensor Process of P3 know as?
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Low Ring Bone
A periosteal proliferation secondary to fractures of the extensor process or hard work on hard surfaces |
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When bony proliferation is extensive what can happen?
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It causes the anterior hoof wall to bulge out
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What can be done for low ring bone?
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No effective treatment
Animal should be pasture sound |
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What are Side Bones?
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Ossification of the lateral cartilages
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Which is more commonly affected lateral lateral or medial lateral?
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Lateral lateral
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What are the clinical signs?
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Often no lameness and they are an incidental finding
Animal may be lame when ossification is occurring or they might fracture one |
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How can it be managed?
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Roll the toe and expand the heels
Remove small chips and leave large ones Correct any imbalance in the foot |
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What is the term for infection and then necrosis of the lateral cartilage?
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Quittor
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What is the aetiology?
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Most commonly as a result of a wound involving the lateral cartilage
Possible complication of sub-solar abscess |
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What is the treatment?
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As the lateral cartilages have very little blood supply the only solution is to remove all diseased cartilage
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How can you help to identify the diseased cartilage in an effort to preserve coronary band?
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Infuse dilute methylene blue into draining tracts
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How can you avoid the coffin joint?
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Maximal extension of the coffin joint retracts the joint capsule
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If the involved cartilage extends distal to the coronary band (usually does) how can that be managed?
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Thin or drill a hole in the hoof wall to remove tissue and create a ventral draining tract
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DISTAL TO THE CARPUS AND TARSUS
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DISTAL TO THE CARPUS AND TARSUS
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How do fractures of the 2nd phalanx occur most commonly?
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Due to abnormal internal stress
e.g. horses in western games that are turning at high speed |
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Which limbs are most often affected?
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70% in the HIND limbs
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Which type of fracture causes a severe leg carrying lameness?
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Comminuted
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When applying a bandage to a broken leg what must you try to do?
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Include the joint above and below the fracture - not always possible
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What type of bandage can be used?
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A Robert Jones bandage
This can also be used with a splint |
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How should an animal with a break be transported?
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Minimise the space either side
Make sure the involved leg is toward the rear of the trailer |
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How are chip fractures of P2 best handled?
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Arthroscopic removal
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When is internal fixation indicated?
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When distal interphalangeal joint is involved
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If only the proximal interphalangeal joint is involved what is indicated?
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Arthrodesis (fusion) of the joint
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When placing a cast what must be monitored?
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Daily observation:
Lameness?, cast intact?, swollen?, smell? flies?, BAR? Any abnormality change the cast |
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What happens in osteochondrosis of the pastern joint?
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Associated with small cysts rather than cartilage flaps
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Is there a severe lameness?
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No only mild
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What is the usual management?
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Arthrodesis of the pastern joint
Although it is possible to drill out the cyst |
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What and where is high ring bone?
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Osteoarthritis of the proximal interphalangeal joint (pastern joint)
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What is the aetiology?
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Horses that make fast turns and stops
Wear and tear 2nd to chip fractures and osteocondrosis |
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When does lameness increase?
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Chronic lameness which increases with increasing work
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Will you be able to see bony proliferation in the joint early on?
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No just at the site of joint capsule attachments
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How is it diagnosed?
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Enlarged joint
Pain with digital flexion/torsion Radiographs showing joint involvment |
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What are the management options?
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Conservative
- NSAIDs and intra articular steroids Surgical - Arthrodesis of pastern joint - use screws of a drill to do this |
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What kind of fractures can occur in P1?
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Axial
Frontal Slightly displaced Severely comminuted |
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Where do most of these occur?
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Front limbs of racing animals
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What must be done if you suspect this type of fracture?
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Take radiographs before doing a complete work up as you may make it worse
Suspect when you have slight lameness after a race esp. when palpation and torsion of pastern causes increased pain |
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When will lag screws not fix the problem?
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If the fracture is severely comminuted - consider euthanasia
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Small chip fractures off the proximal dorsal margin of the 1st phalanx are common in which joint?
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Metacarpal phalangeal joint of race horses
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What is the main cause?
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Trauma as a result of marked extension of fetlock joint
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How are these fractures managed?
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Small fractures are covered by synovial membranes rapidly and a lot heal without intervention
Surgical removal with an arthroscope if bigger |
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What are the types of fractures which occur on the caudal proximal border of P1?
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1 - fx involve axial palmar or plantar rim
2 - fx involve abaxial palmar or plantar rim |
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Fractures of the caudal proximal border of P1 typically occur in which limbs?
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Rear limbs
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Type 2 fractures are not normally removed except when?
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When they are large and definitely the result of external trauma - removed or stabilised with a bone screw
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What is the proper name for "osslets" - periosteal proliferation at the attachment of the joint capsule of the fetlock?
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Osteoarthritis of the fetlock joint
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What are the clinical signs?
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Initially - heat, effusion and pain with flexion
Distended fetlock joint Marked reduction in range of motion |
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How can it be managed?
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If it is still at the early stage of synovitis and capsulitis
- NSAIDs, steroids, hyaluronan Stand horse in ice water before race In severe cases arthrodesis to get pasture sound |
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When trying to manage OCD in the fetlock joint where is the injury surgically inaccessible?
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On the palmar/plantar aspect = permanent lameness
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How is OCD treated?
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By debriding the lesions
Small cystic lesions treated with hyaluronan |
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What occurs secondary to rupture of the medial or lateral collateral ligament?
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Luxation of the fetlock
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What is the prognosis?
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Poor
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Sesamoiditis is diagnosed how?
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Pain on flexion and pressure
Proliferative response Lack of density in sesamoids |
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How is it treated?
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Rest and free pasture exercise
NSAIDs |
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What type of fractures can the proximal sesamoids get?
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Apical
Mid-body Basilar Abaxial Axial Comminuted |
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How are they managed?
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Apical fractures involving <1/3 of the bone are removed
Mid-body - lag screw or cerclage wire Basal - is small and not the complete width remove If it extends to the width poor px as distal sesamoid ligaments are involved Abaxial - remove or rest Sagittal - wire |
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In a basal fracture why are screws contraindicated?
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The bone will fragment
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When is an arthrodesis of the fetlock joint indicated?
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A break down injury where the suspensory apparatus has been destroyed
Chronic painful condition that wont respond to therapy |
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How is it performed?
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Scrape off the cartilage and fix the joint with a plate
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When arthrodesing a joint how long must the cast remain?
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Replaced after 3 weeks and maintained until there is radiographic evidence of bone proliferation
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What is the prognosis?
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Pasture soundness only
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Where is the most frequent site of OCD in the fetlock?
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Dorsal sagittal ridge
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Why?
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Failure of endochondral ossification
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Management?
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Rest is best in the young
Curretage with arthroscope best in older animal |
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What is chronic proliferative synovitis otherwise known as?
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Villonodular synovitis
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What is it?
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Proliferation of the synovial membrane of the metacarpal phalangeal joint
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What are the primary and secondary causes?
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Primary
Repeated hyperextension of the fetlock and trauma to synovial membrane Secondary Dorsal phalangeal fractures that are not removed and cause irritation and proliferation of synovial membrane |
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What are the clinical signs?
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Firm enlargement of dorsal aspect of joint
Mod-severe lameness More common in Standardbreds |
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What does it look like on radiographs?
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Bone lysis on dorsal aspect of the distal metacarpus adjacent to synovial mass
Often contrast will show a filling defect |
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How is primary chronic proliferative synovitis managed?
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Remove synovial mass
Injection of joint with steroids and hyaluronan will allow continued use but not cure |
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What is a valgus deformity?
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An angular limb deformity where the feet stick out laterally - "knock-kneed"
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What is a varus deformity?
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Medial deviation - "bow legged"
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What should you do if the deformity is due to a weakness of the supporting structures?
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Stall rest, walking, swimming
NO casts/splints |
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What if it is due to hypoplasia of the carpal bones?
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Stall rest if not severe
If not casts or splints until normal ossification |
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What if the deformity is due to metaphysial dysplasia?
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4-6wks stall rest
Splints Braces Trimming the feet Surgery |
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What does periosteal stripping do?
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Stimulates bone growth on the concave side of the limb
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What does physial irritation do?
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Stimulates growth on the side that the physis is irritated i.e. concave side
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What are the age limits on growth stimulation?
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Distal radius - 6 months
Distal tibia - 4 months Distal MC/MT and proximal P1 - 2 months |
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Surgery can also be used to retard growth, what are the age limitations?
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Distal radius - 12 months
Distal tibia - 8 months Distal MC/MT and proximal P1 - 4 months |
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How can growth be retarded?
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Screws and wire
Staples Bone plates One transphyseal |
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What must you be careful to look out for?
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When leg looks straight again - take out the hardware!
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What does it mean if a leg that was straight suddenly becomes deformed?
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Look for lameness in the other limb
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If the animal has epiphyseal dysplasia what can be done?
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Doesn't respond well to stimulation or retardation of physeal growth
Animal won't perform well |
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If there is a congenital flexural deformity what can be done?
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Can give large doses of tetracycline IV
Splints to stretch flexor tendons Casting the limbs will cause relaxation of tendons Toe extensions Inferior check ligament desmotomy is seldom needed |
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What are the 2 types of acquired flexural deformity?
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Coffin and pastern joint flexion (club foot)
Hyperflexion of fetlock |
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What is type I and type II coffin and pastern joint flexion?
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I - hoof wall angle with sole surface is <90 degrees
II - angle is >90 degrees |
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Why do these deformities occur?
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Secondary to pain - if full weight is not born when limb is growing tendons don't stretch
Nutritional - excess energy = rapid bone growth |
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What are the clinical signs in a foal that is less than 5 months?
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Club foot
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What if the foal is older than 5 months?
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Upright fetlock may even buckle forward
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Why should you manage a lameness aggressively in a young animal?
|
Because it only takes 2 weeks of lameness for an angular limb deformity to develop
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How can shoeing cure a club foot?
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Shorten the heels and extend the toe
- increases tension on digital flexor tendons |
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How can shoeing cure hyperflexion of the fetlock?
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Elevate the heel and extend the toe
- takes pressure off DDF tendon and increases tension on SDF |
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What surgeries can be performed?
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Club foot
Inferior check ligament desmotomy Upright pastern/hyperflexion Superior check ligament desmotomy |
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Which check ligament do the DDF and SDF attach to the skeleton via?
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DDF = inferior
SDF = superior |
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Why should you manage a lameness aggressively in a young animal?
|
Because it only takes 2 weeks of lameness for an angular limb deformity to develop
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How can shoeing cure a club foot?
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Shorten the heels and extend the toe
- increases tension on digital flexor tendons |
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How can shoeing cure hyperextension of the fetlock?
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Elevate the heel and extend the toe
- takes pressure off DDF tendon and increases tension on SDF |
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What surgeries can be performed?
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Club foot
Inferior check ligament desmotomy Upright pastern/hyperextension Superior check ligament desmotomy |
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Which check ligament do the DDF and SDF attach to the skeleton via?
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DDF = inferior
SDF = superior |
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In a metacarpal/tarsal fracture where does the break most commonly occur?
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The lateral condyle of the distal metacarpal/tarsal condyles
85% of condylar fractures |
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What would happen if the medial condyle was fractured?
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Often the fracture extends up the metacarpus/tarsus and may completely disrupt the bone
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How are these fractures classified?
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Incomplete - not all the way through the cortex
Complete non displaced Complete displaced Fractures that propagate up through diaphysis |
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How are lateral fractures managed?
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Compression bandage until repair is ok
Non-displaced fractures can be managed with stall rest otherwise use internal fixation of at least 2 screws Displaced fractures often require open reduction |
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How can a medial fracture be repaired?
|
Evaluate for dorsal propagation - very common to have sagittal or spiral fractures extending proximally
Best way to repair = 2 bone plates |
|
|
What is the most common long bone fracture?
|
A displaced fracture of metacarpal/tarsal 3
|
|
|
Why is it quite common for this to be a compound fracture?
|
Little soft tissue
|
|
|
What does the repair involve?
|
Internal fixation with 2 bone plates
Guarded prognosis |
|
|
What is the name of the condition where there is an osteitis involving the dorsal surface of the 3rd metacarpal bones which affects 2yo race horses?
|
Dorsal metacarpal disease
"Bucked shins" |
|
|
What is the aetiology?
|
Too much of the incorrect work at an early age - jogging and galloping trying to develop stamina
They should have increased sessions at racing speed |
|
|
In the US which limb is most affected and why?
|
The left metacarpus as in the US they always race anti-clockwise
|
|
|
What kind of fracture must you rule out in radiographs?
|
Rule out "saucer" fractures of the metacarpus
|
|
|
How is it managed?
|
Rest, physical therapy, NSAIDs
Once horse isn't sore have more emphasis on racing speeds |
|
|
Where do stress fractures of the 3rd metacarpus develop?
|
On the anterior lateral aspect
|
|
|
How can healing be encouraged?
|
Cortical drilling and screw placement
|
|
|
Splints are what?
|
Exostosis (formation of new bone on bone) on the 2nd and 4th metacarpal/tasal bones
Routinely associated with straining of the interosseous ligament attaching these bones to the 3rd MC/T and the resulting periosteal proliferation |
|
|
Which splint bone is most commonly involved?
|
2nd metacarpal
|
|
|
At what age does the risk of getting classical splints go away?
|
Animals over 4yo as this is when ligament normally ossifies
|
|
|
What is the difference between acute and chronic splints?
|
Acute - lameness w/ swelling and pain on palpation
Chronic - firm bony swelling, commonly no lameness or pain |
|
|
What happens if exercise is continued during the acute stage?
|
Periosteal proliferation will be stimulated
Usually 3-4wks of stall rest is adequate |
|
|
When would surgery be indicated?
|
If proliferation gets so much it impinges on the suspensory apparatus
|
|
|
How are splint fractures caused?
|
External trauma - kicks
Internal stress - hyperextension of digit |
|
|
How is it managed?
|
Conservatively
Remove fragment Bone plate and screws (not into 3rd MC) |
|
|
What are "bowed tendons"?
|
SDF tendonitis
|
|
|
What is the difference between high bow, mid bow, low bow and pastern bow?
|
High = within carpal sheath
Mid = b/w carpal and digital sheaths Low = within digital sheath Pastern = caudal to P1 |
|
|
Which limbs are most commonly involved?
|
SDF tendons of front legs
Caudal distension of tendon |
|
|
How is it initially managed?
|
Ice, NSAIDs, steroids, bandages
Perform U/S |
|
|
Long term?
|
Aim is to allow tendon to heal with minimal scarring and proper collagen
Stem cells Injection of hyaluronan Polysulfated glycosaminoglycan Rest Slow return to exercise |
|
|
What can be done surgically?
|
Transection of superior (proximal) check ligament
Division of volar annular ligament Tendon splitting - not great |
|
|
What is Suspensory desmitis?
|
An inflammation of the interosseous muscle (suspensory ligment)
|
|
|
Aetiology?
|
Trauma associated with exercise
Impingement of enlarged splint bones |
|
|
Management?
|
Rest
NSAIDs Splitting the fibres - esp if involve sesamoid branches Shock waves Injection of the origin with bone marrow |
|
|
What does the limb look like if the SDF tendon is lacerated?
|
Fetlock is dropped but sole of foot is on the ground
|
|
|
DDF?
|
Sole of the foot isn't on the ground and the toe is raised
|
|
|
Both SDF and DDF?
|
Palmar/plantar aspect of the fetlock is on the ground
|
|
|
How is it treated?
|
Control the bleeding with pressure bandages
Suture tendons & soft tissue after evaluation and debridement of wound (loop lock best) Repair must be supported by a cast or splint min 8wks Following cast/splint a support shoe/brace will be necessary to stretch out tendons |
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|
What conservative management is there?
|
If laceration is distal to fetlock involving only DDF - raised trailer shoe reduced over 8wks
If above fetlock with just SDF - fetlock will be dropped but no support needed If above fetlock and involves both tendons - Leg brace/board splint |
|
|
What is a major complication?
|
Laminitis in contralateral limb - can cast this limb also to help support weight
|
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|
What will the horse look like if it has lacerated it's extensor tendons?
|
Will be walking on the front of it's fetlock
|
|
|
Management?
|
Splint and support bandage
Take measures to limit excessive granulation tissue |
|
|
Flexor tendon weakness occurs at what age?
|
In new born foals - rock back on the bulbs of their heels and don't bear weight on the sole of the foot
|
|
|
How can it be fixed?
|
Rasp the heel to flatten it and use hoof acrylic to attach a piece of hardwood or plastic to the sole so it acts like a trailer show (extends caudally)
Casts or support bandages are NOT indicated |
|
|
What would you expect if you saw a considerable swelling on the anterior aspect of the carpus in a young foal?
|
Common digital extensor tendon rupture
|
|
|
Why does this occur?
|
Foal is in the field with mum and runs after her to the point of exhaustion
|
|
|
What can be done?
|
Stall rest and compression bandage to control effusion
Use support bandages or casts if knuckeling is occuring Don't allow free exercise at pasture for several weeks after birth |
|
|
Where is it most common to have problems in the carpus?
|
The radial carpal and 3rd carpal bones
|
|
|
What is a degenerative disease of the carpal joints called?
|
Carpitis
|
|
|
How is it predisposed?
|
Exercise to fatigue
Poor conformation - 'back at the knee' Poor shoeing - toe grabs |
|
|
What else may cause it?
|
Chip fractures
Osteochondral defects in the cartilage Fractures of carpal bones |
|
|
How is it diagnosed?
|
Lameness, distension of carpal joint capsule, radiographs showing fractures
|
|
|
Where are the most common areas of chip fractures in thoroughbred and racing quarter horses?
|
Distal radial carpal bone - most common
then: Proximal 3rd carpal Craniolateral aspect of distal radius Proximal intermediate CB Slab fractures of 3rd CB |
|
|
Standardbreds do not commonly have fractures where?
|
Distal radius involving the radiocarpal joint
|
|
|
Which joints communicate in the carpus?
|
Radial carpal joint - no communication
Middle carpal and carpometacarpal joints communicate |
|
|
What can carpitis develop into?
|
Chronic synovitis
DJD |
|
|
A flexural deformity of the carpus can be primary at birth or secondary to what?
|
Pain - prevents full extension
Rupture of common digital extensor |
|
|
How can you correct it?
|
Congenital - IV tetracycline, proper nutrition, tube casts
Acquired - correct primary problem Surgery can be performed - tenotomy but has a poor Px |
|
|
What happens when there is radial nerve paralysis?
|
Inability to extend the carpus and the digit
|
|
|
What could be the cause of paralysis?
|
Trauma to the nerve at the humerous
Overstretching - hyperextension of the elbow Prolonged lateral recombancy with no padding Laceration of the nerve |
|
|
What does the horse look like?
|
Cannot advance limb
Stands with anterior fetlock on the ground and elbow droppedd If the foot is placed under the animal it can bear weight - unless it is more severe and involves the brachial plexus |
|
|
How is it managed?
|
Protective bandages on limb
Stall rest Cast/splint Surgery if lacerated |
|
|
What are the clinical signs of fracture of the olecranon?
|
Usually severe lameness
Swelling and crepitation Stand with elbow lower and carpus flexed |
|
|
Why is stall rest for 8 weeks not the best treatment?
|
Complications:
Flexor contracture Atrophy of triceps Non union DJD Valgus limb deformitity and laminitis in the other limb |
|
|
What surgical options are there for <6 months?
|
Pins and wire
|
|
|
>6months?
|
Bone plate attached to caudal aspect of olecranon
|
|
|
How do you know if the repair has been successful?
|
The animal should be able to bear some weight while in recovery
|
|
|
What are the surgical complications?
|
Unstable repair - won't bear weight
Destruction of implants during recovery Infection Arthritis of elbow Prognosis is good if no joint involvement |
|
|
What can irritation of the bicipital bursa cause? what horses are most at risk?
|
Bicipital bursitis
In draft horses that are pulling heavy loads |
|
|
How do you treat non-infectious bursitis?
|
Rest
NSAIDs Intrabursal steroids |
|
|
Infectious bursitis?
|
Culture and sensitivity
Abx Drainage and flushing |
|
|
What is osteochondrosis of the shoulder joint?
|
Disturbance in endochondral ossification resulting in defects in subchondral bone and abnormal overlying cartilage
|
|
|
What is the aetiology?
|
Rapid growth
Excess energy intake in young growing animals |
|
|
How is it treated?
|
Extensive rest
Arthroscopic curettage to remove unhealthy cartilage |
|
|
What aetiologies can cause athritis of the shoulder joint?
|
OCD
Fractures Secondary to haematogenous infection of the joint (young animals) |
|
|
What is "Sweeny"?
|
Suprascapular paralysis
No nerve supply to supraspinatus and infraspinatus muscles resulting in marked atrophy Caused by trauma to the point of shoulder |
|
|
What happens in the early stages before atrophy develops?
|
Lateral movement of the entire shoulder joint when limb bears weight
Often corrects after 6-7mths |
|
|
If atrophy occurs what can be done?
|
Nerve can be cut free from scar tissue
If atrophy has been present for >10months Px is poor for return of muscle mass |
|
|
When a horse has a fractured humerus what is the best treatment?
|
Stall rest!
Repair themselves after a few months |
|
|
REAR LIMB
|
REAR LIMB
|
|
|
Of the four tarsal joints which ones communicate?
|
Tarsocrural (tibiotarsal) and the proximal intertarsal communicate
In most horses neither the distal intertarsal or the tarsometatarsal communicate |
|
|
What is the name of the condition which involved osteoarthritis of the distal 3 hock joints?
|
Bone spavin
|
|
|
Bone spavin is a chronic condition and increased work for several days usually increases the lameness. What tends to happen during a session of work?
|
There is reduced flexion of the hock and the toe gets dragged.
The horse warms up and out of the lameness |
|
|
Does the horse move the lame leg closer to or further away from the midline?
|
Closer to midline
|
|
|
How is bone spavin diagnosed?
|
Hx, reaction to flexion tests, never and joint blocks, Rx
|
|
|
What will happen is the animal is continually exercised?
|
DJD will become so severe that ankylosis will occur and the animal will become using sound
|
|
|
Is excessive rest a good idea?
|
Not really
Can be managed medically with NSAIDs, steroids etc. |
|
|
What are the other means of treatment?
|
Shockwave therapy
Corrective shoeing Cunean tenotomy Surgical arthrodesis of distal hock joints - manually or by injecting irritants e.g. ethyl alcohol |
|
|
What is bog spavin?
|
A synovial distension of the tibiotarsal joint
|
|
|
Many times the horse isn't lame and the condition develops acutely - what can be seen?
|
The joint is most obviously distended on the anterior medial aspect of the joint
|
|
|
If there is no other problems the condition is just cosmetic, what must you do to rule out other conditions?
|
Radiographs
Culture of synovial fluid |
|
|
What can be used to reduce the swelling?
|
Remove the fluid
Intra articular injections - steroid, atropine, progesterone Pressure bandage |
|
|
When are you likely to see tarsal bone necrosis and collapse?
|
In the neonatal foal
|
|
|
What are the signs?
|
Swelling, pain and excessive angularity of the hock
Rx show degeneration of 3rd tarsal bone |
|
|
What can be done in these cases?
|
Tube casts might work but they don't routinely respond so euthanasia
|
|
|
What is the name for a desmitis of the plantar ligament on the plantar aspect of the hock?
|
Curb
Usually from excessive kicking or poor conformation |
|
|
What will be seen clinically?
|
A firm swelling over the plantar aspect of the hock and lameness and pain over the area
|
|
|
Curb can be treated medically, what is the prognosis?
|
Animal normally returns to athletic soundness but it is common for swelling to persist
|
|
|
What is OCD of the tarsus?
|
Unhealthy subchondral bone resulting in unhealthy cartilage
|
|
|
What is the most common area of the tarsus affected by DJD?
|
Cranial distal aspect of the intermediate ridge of the tibia
then Lateral trochlear ridge of talus then Medial trochlear ridge of talus |
|
|
When is arthroscopic surgery to remove fragments and curette indicated?
|
If the horse is lame or of there is effusion of tibiotarsal joint
|
|
|
What is a "Capped" hock?
|
A swelling involving a SQ bursa at the point of the hock - associated with "kickers"
|
|
|
How are acute and chronic cases managed?
|
Acute = Aspirate fluid, injections as in bog spavin, a snug bandage
Chronic = Draining and injecting or do nothing If there is excessive fluid - insert surgical drain Surgically remove all tissue |
|
|
What happens it the superficial flexor tendon gets luxated?
|
Marked swelling
Lameness Tendon movement |
|
|
What is the name for an idiopathic distension of the sheath of the deep flexor tendon (tarsal sheath)?
|
Thoroughpin
From chronic low grade trauma, usually no lameness and is a blemish |
|
|
What is Stringhalt?
|
Abnormal gait in which there are varying degrees of hyperflexion of the rear limb
|
|
|
What are the 2 forms of Stringhalt?
|
1. Associated with pastures with a high dandelion number (Australia) - dandelion toxicity
Commonly BIlateral 2. Sporadic - no definite aetiology Usually UNIlateral |
|
|
When is the hyperflexion usually worse?
|
Cold weather
When the horse backs When the horse turns After the horse has rested |
|
|
With dandelion toxicity just remove the source, what can be done for the sporadic type?
|
Lateral digital extensor tenectomy
|
|
|
What is Fibrotic and Ossifying Myopathy?
|
A condition which causes an alteration in the gait that is only seen when the animal is moving at the WALK
|
|
|
What is the aetiology?
|
Trauma and healing with fibrosis &/or ossification of the semitendinosis, semimembranosus &/or biceps femoris muscle
|
|
|
What does the gait look like?
|
When moving at a walk the affected limb is pulled to the rear just prior to the foot hitting the ground
|
|
|
What is the treatment?
|
Partial myectomy - NOT recommended too many complications
Transection of the insertion of the tendon of the semitendinosus muscle at the caudomedial aspect of the proximal tibia |
|
|
What are some of the proposed aetiologies of OCD lesions of the trochlear ridge of the femur?
|
Nutrition
Rapid growth Genetics Trauma Copper deficiency |
|
|
When do signs usually become apparent?
|
In young animals from 6mths to 2yo
- synovial effusion of femoropatellar joint - slight to moderate lameness |
|
|
When is the prognosis good?
|
If just the lateral ridge is involved
Less favourable if both medial and lateral ridges are involved |
|
|
How are cystic lesions of the medial femoral condyle treated?
|
Conservative - rest, proper nutrition
Surgical - curret the cystic lesion |
|
|
Why does upward fixation of the patella occur?
|
When the medial patella ligament becomes fixed proximal to the medial condyle of the femur
Hereditary, trauma with over-extension, poor conditioning |
|
|
What is more common, complete upward fixation - leg extended and cannot be flexed - or momentary fixation - slight hesitation in gait prior to foot leaving the ground?
|
Momentary upward fixation is more common
|
|
|
What can be done for acute upward fixation?
|
Back the horse up
Startle horse so it jumps backwards Pull leg forward while forcing patella medially and distally Medial patella desmotomy |
|
|
Momentary?
|
Slowly increase exercise to increase muscle tone
Inject patella ligaments with mild irritant Medial patella desmotomy Split patella ligaments |
|
|
FOOD ANIMAL
|
FOOD ANIMAL
|
|
|
Where is 90% of all lameness?
|
In the foot
|
|
|
When trimming the rear feet what claw should you start with?
|
The medial claw
Start with the lateral claw when trimming the front feet |
|
|
What is one of the most common causes of lameness in dairy cattle?
|
Digital dermatitis - "hairy heel warts"
|
|
|
What do the lesions look like?
|
2-6cm circumscribed lesions at the junction of skin and horn at the heel, midway between the claws
|
|
|
Treatment?
|
Parenteral or topical antibiotics
Copper sulphate foot bath |
|
|
What is heel erosion or "slurry heel"?
|
Marked pitting erosions of the heel
|
|
|
Why does slurry heel occur?
|
The soft horn at the bulb of the heels is weakened by exposure to excessive moisture (slurry) which softens the horn and allows bacteria and irritants to affect the hoof horn
|
|
|
Which feet are most commonly involved?
|
Rear feet
|
|
|
What is Screw Claw?
|
The phalanges show axial rotation
|
|
|
Which claws are most commonly involved?
|
Lateral claws of rear feet
Medial claws of fore feet |
|
|
When is the problem likely to develop?
|
Problem becomes obvious <3yo and unlikely >5yo
|
|
|
Can screw claw be corrected?
|
No but corrective trimming can reduce severity
Don't breed these animals |
|
|
How does a white line abscess occur?
|
When foreign material gains access to sensitive tissue at the junction of the wall and sole.
|
|
|
Where will purulent exudate drain if the abscess isn't treated?
|
At the white line
At the coronary band Under run the sole |
|
|
How are they managed?
|
Establish adequate ventral drainage and remove all undermined sole
Consider putting a block on the sound claw in severe cases |
|
|
What are reasons for getting a Sole Ulcer (pododermatitis circumscripta)?
|
Excessive weight bearing on sole surface
Subclinical laminitis Excessive moisture and wear of sole Sole pressure causing ischemic necrosis Poor claw trimming |
|
|
How are sole ulcers managed?
|
Amputation of granulation tissue
Remove undermined sole Trim affected claw to transfer weight onto healthy claw Some animals never recover and need trimming every few months |
|
|
What is another name for Interdigital necrobacillosis?
|
Foot Rot
Infection of soft tissue which can progress to bones and joints |
|
|
What organism is responsible?
|
Fusobacterium necrophorum
|
|
|
What are the clinical signs?
|
Sudden onset of very painful lameness
Might involve more than one limb Swelling above coronary band Red and swollen skin and soft tissue |
|
|
How do you treat it?
|
Antibiotics
Surgical removal of dead tissue Severe cases might need claw amputation/excessive drainage |
|
|
What are "corns" in ruminants?
|
Hyperplasia of skin in the interdigital space
|
|
|
In which animals are corns a greater problem?
|
In large heavy cows and beef bulls
|
|
|
How is it managed?
|
Surgically remove the tissue
Bandage foot Wire claws together |
|
|
When should you remove a horizontal hoof crack?
|
If there is pain the segment below the crack should be removed
|
|
|
If an animal has fractured the P3 of a medial claw, how will it stand?
|
Cross-legged
|
|
|
How are P3 fractures managed?
|
Wood block on the sound claw
Wire fractured claw to the wooden block with digit slightly flexed Stall rest ~8wks |
|
|
A long bone fracture is usually a result of external trauma and present with acute lameness, when would you not bother to repair?
|
If the animal can't stand on three legs
|
|
|
How are fractures of the lower leg (below carpus and tarsus) managed?
|
Full limb cast
- consider transfixation pins and cast |
|
|
Radius and tibia?
|
Splint immobilisation - poor px
|
|
|
Femur and humerus?
|
Stall rest
|
|
|
What can you use for rear limb fractures or stifle joint trauma?
|
A Walker Splint
|
|
|
What will an animal look like with upward fixation of the patella?
|
It will have a straight rear limb
|
|
|
Clinical signs?
|
Catching in the gait just after full extension of the rear leg
Sometimes complete locking of the patella dorsal to the medial femoral condyle |
|
|
What procedure needs to be performed?
|
Medial patella desmotomy
On BOTH legs as the other leg will have the same problem eventually |
|
|
SURGERY OF INTEGUMENT
|
SURGERY OF INTEGUMENT
|
|
|
Define abrasion
|
A wound that does not extend through the dermis
|
|
|
Define laceration
|
Tearing without extreme loss of tissue
|
|
|
Define incision
|
Cut from a sharp instrument or scalpel
|
|
|
Define avulsion
|
Tearing wound with considerable loss of tissue
|
|
|
Define contusion
|
No break in the skin but deeper damage i.e. a bruise
|
|
|
What is the first thing that should be done when presented with a bleeding wound?
|
Control haemorrhage - apply pressure, ligate if needed
|
|
|
How must a wound be assessed?
|
Assess it initially - location, depth, vital structures, contamination
Detailed exam - Clean the wound, KY jelly and clip Explore depths of wound - fractures, foreign bodies, vessels |
|
|
How many units of tetanus antitoxin will provide immediate protection?
|
1500 units
|
|
|
Can toxoid and antitoxin be given together?
|
Yes - provides long term as well as immediate protection
|
|
|
Which animals are more susceptible to tetanus?
|
Horses then sheep & goats but cattle and swine are not that susceptible at all
|
|
|
What must you be cautious of when giving tetanus antitoxin to older horses?
|
Serum Hepatitis (Theiler's Disease)
|
|
|
When would a wound need antibiotics?
|
If it is severe give Abx for 3-4 days to control cellulitis
Or in wounds involving synovial structures |
|
|
What are the purposes of bandages?
|
Prevent dirt contaminating wound
Reduce irritation Reduce motion |
|
|
When can a wound be closed by primary surgical closure?
|
Age - <10hrs
Degree of contamination - clean! Location - movement of wound edges must be minimal Tissue remaining Blood supply General condition of the animal |
|
|
When would you consider using delayed primary closure?
|
Must have all criteria for primary closure except that it may be heavily contaminated and a number of hours old.
|
|
|
What is the technique for delayed primary closure?
|
Thoroughly debride and cleanse wound
Parenteral antibiotics Wound is medicated and bandaged to control infection for ~3days After that time it is debrided and closed primarily |
|
|
If there isn't enough tissue to use a primary closure what technique can be used?
|
Facilitated wound contraction
Place continuous horizontal interdermal sutures and tighten them daily and it will stretch the skin |
|
|
When are skin grafts mainly used?
|
For lower leg wounds to increase speed of wound epithelialization
|
|
|
What are autographs?
|
Skin is transferred from another site on the same animal
|
|
|
What is required for the graft to take?
|
A healthy non-infected granulation tissue bed
|
|
|
When can the tissue bed be slightly infected and the graph will still take?
|
Pinch, punch or tunneled grafts
|
|
|
What types of grafts are there?
|
Full thickness
Split thickness Mesh Pinch Punch Tunnel |
|
|
Where are the common donor sites?
|
Pectorals or ventral abdomen
|
|
|
Which grafts take better?
|
Small and thin
|
|
|
What is presuturing used for?
|
Used to close a defect or remove a blemish
|
|
|
How can you diagnose if a joint is involved in a wound?
|
Look for synovial fluid in the wound
See if you can flush the joint by injecting sterile saline into the joint at a point away from the wound Evaluate synovial fluid - although negative culture doesn't mean it's not involved |
|
|
How do you manage a joint wound <8hrs old with minimal tissue loss?
|
Flush with several litres of saline and close under suture
Maintain parenteral Abx levels Consider limb perfusion |
|
|
How do you manage a joint wound >8hrs old with minimal tissue loss?
|
Thoroughly clean and debride wound
Bandage and maintain on Abx with daily bandage changes for 3 days Close with delayed primary closure and continue Abx |
|
|
What if the joint cannot be closed under suture?
|
Thoroughly clean and debride
Maintain with sterile dressing and Abx until joint capsule closes |
|
|
What is "proud flesh"?
|
Excessive granulation tissue
|
|
|
What are the predisposing factors for getting proud flesh?
|
Minimal muscle mass
Limited excess skin Continual irritation |
|
|
Why is proud flesh a problem?
|
It interferes with epithelialization and wound contraction
|
|
|
How can you remove it?
|
Surgically cut it out
Apply caustic substances |
|
|
How can you control development of excessive granulation tissue?
|
Reduce irritation and motion - bandage, splints and casts
Steroid containing ointments Mild caustic agents Enzyme preparations |
