EMERGENCY MANAGEMENT OF EQUINE ORTHOPEDIC INJURIES

“Field First-Aid & Emergency Transport”Dane M. Tatarniuk, DVM

December 10th, 2013

Equine Musculoskeletal First-Aid Overview:- Considerations for management of orthopedic emergencies - Classification of fractures - Forms of external stabilization for transport from the field to

hospital setting

Communication/History:- Things to identify during your history:

o What type of injury is sustained?o Is it known how the injury occurred?o Is it known when the injury occurred?o How lame is the horse? Weight bearing?o Is there any ongoing bleeding?

- Maintain composure, keep the owner calm, speak directly- If horse is lame, keep it confined- Verbalize a clear estimate of how much time it will take for

you to arrive- Ask the owner to organize hooking-up a trailer, if referral to

your hospital is a potential outcome- Give owner any specific recommendations for immediate

management (ie, bandaging wound, give phenylbutazone, etc.) based on the information you have available

Supplies to consider bringing in the vet-truck:- Sedatives, IV anesthetics (ketamine), antibiotics, pain

medication, radiograph machine, ultrasound machine, clippers, surgical instruments & suture, bandaging material, splinting material, cast material, euthanasia solution

On-farm Examination:- Assess status of the horse?

o QAR, BAR, weight bearing, recumbent, painful, anxious/stressed, adequately restrained, etc.

- Assess environment?o In pasture/stall/barn, electricity present, horse trailer

available, how did horse injure itself, etc.

1

- Maintain safety of those involved (owners, assistants, bystanders)

o Sedate if necessary- Physical exam

o HR often elevated (60+ bpm) with fractures, less commonly elevated with lacerations

o Systemic compromise – not very common but look for signs of shock, neurological symptoms, etc.

Hypovolemic shock – HR, mucus membranes, CRT

Can measure systemic lactate if you have hand-held meter in truck

Give hypertonic saline followed by isotonic crystalloids, stop ongoing bleeding

Certain fractures can lacerate large arteries Illiac artery from pelvic fracture Femoral/Popliteal artery from

femoral/proximal tibia fracture Abdominal trauma -> splenic rupture ->

hemoabdomeno Don’t miss a colic – horses can thrash around and

lacerate/fracture themselves due to gastrointestinal pain.

- Musculoskeletal examo Where is the injury – instability, swelling, laceration

present, what anatomical structures are in the area, contamination present, etc.

- Formulate a plano Further diagnostics (x-ray, synoviocentesis, etc.)

needed?o Discussion with owner regarding injury, prognosis for

return to athletic function, potential complications, estimate of cost incurred

If unsure, contact referral hospital for further clarification

o Management On-farm therapy (ie, laceration repair) On-farm stabilization of injury for referral (ie,

splinting) Euthanasia

Differentials for non-weight bearing lameness:- Fracture(s)- Foot abscess- Cellulitis

2

- Septic synovial structure(s)o Joint, tendon sheath, bursa

- Solar puncture- Lacerated tendon(s)

Clinical features of fractures:- Visualization of displaced, open fracture- Instability on flexion/extension/palpation- Crepitus + swelling- Pain- If not non-weight bearing lame, significant (grade 3+)

lameness

Avoid:- Avoid performing nerve blocks, as horse may place excessive

weight/force on limb, which can lead to further displacement of fracture and damage to soft tissues

- Avoid moving horse around until fracture is stabilized

Challenges of Fracture Repair:- Size:

o It takes a significant force to break a horse bone Soft tissue damage is common

o Implants placed must be strong enough to withstand forces applied

Most bone plates are manufactured for humanso Horses are not graceful during anesthetic recovery

Risk of bending or breaking plate, or re-fracturing limb during anesthetic recovery

o Secondary complications can occur from compensation Overload other limbs -> laminitis Prolonged recumbancy -> myopathy, neuropathy,

sores- Cost / Management:

o If the fracture is amendable to internal fixation repair, the cost is usually significant ($3000 to $10000) and hospitalization is prolonged due to aftercare.

Prognosis for fracture repair:- With surgical repair, some fractures have poor prognosis,

while others have excellent prognosis- Depends on many variables:

o What bone is fracturedo Configuration of fractureo Open vs. Closed

3

o Duration of fractureo Soft tissue or vascular damageo Articular vs. non-articularo Purpose of horse

Athlete vs. pasture sound peto Age, breed, weight of horse

- If unsure, best option is to contact referral center and speak to an surgical specialist

Fracture Classification:1. Complete vs. Incomplete2. Displaced vs. Non-displaced3. Open vs. Closed

a) Type 1 – Less than 1cm skin perforated by sharp piece of bone; little contamination & skin damage.

b) Type 2 – Larger skin laceration, but minimal loss of soft tissue, minimal bone exposure & minimal contamination

c) Type 3 – Extensive laceration, massive skin defect, gross contamination evident4. Configuration

– Transverse, oblique, spiral, comminuted, avulsion5. Location

– Bone(s) & Limb– Diaphysis, epiphysis, metaphysis, physis

Goals of Fracture Stabilization:1. Prevention of damage to neurovascular structures2. Keeping fractured bone from penetrating skin and becoming an open fracture3. Protect an open fracture from contamination through skin opening4. Stabilize the limb to relieve patient anxiety and minimize further fracture displacement5. Minimize further damage to the ends of bone (& soft tissue)

Restraint & Analgesia for Fracture Stabilization:- Want to restrain the painful & anxious horse for proper

placement of bandage/splint- Don’t want to increase incoordination or ataxia- Options

o Alpha-2 agonists Xylazine, romifidine, detomidine

o Acepromazine No analgesia

4

May be contra-indicated in hemodynamically unstable patient due to induced hypotension

o Butorphanol Only in combination with alpha-2 agonist,

otherwise will be excitatory Decent analgesia

- If horse is still painful following administration of NSAID and sedation, can add other opioid

o ie, Morphine (0.1 mg/kg intramuscular, TID)o Use judgment – don’t want to make them feel ‘too’ good

on the limb -> more weight bearing, less protection

Splints:- Characteristics:

o Economicalo Can be applied in a field setting, on a standing horse o Neutralizes forces on the fractureo Does not impede the horse from moving

- Materials:o Bandage

Sheet or roll cotton, combine Brown gauze, vetwrap, Elasticon

o Splint PVC pipe, wood, hockey stick, broom handle,

metal baro Cast

Cast over the bandage = bandage casto Pre-made splints

‘Kimzey Leg Saver’ splints available

Biomechanical Forces:- Some specific considerations:

o Extensor muscles can abduct the limbo Suspensory apparatus

Instead of flexion at the fetlock joint, bending forces will be placed at the fracture site (in distal limb fractures)

Need to keep fetlock angle neutral (straight) during stabilization

o Reciprocal apparatus Fractures of the tibia & tarsus can be displaced

by flexion of the stifle Can’t necessary prevent stifle flexion with

splinting, but can minimize amount of flexion that occurs

5

Splinting Methodology:- Splinting is based on the biomechanical forces imparted on

the fracture, as well as ability to counter-act those forces- Therefore, different fractured bones require different types of

splints:

6

Area SplintForelimb Phalanx Dorsal

Metacarpus Lateral & PalmarRadius Lateral to withers,

palmar to elbowCalcaneus Palmar to elbowHumerus None

Hindlimb Phalanx PlantarMetatarsus Lateral, Plantar

Tarsus, Tibia Lateral up to tuber coxae, plantar

Stifle, Femur None

Recumbent Horse:- Utilize sedation- If horse very unsafe, consider IV anesthetics (ketamine)- Stabilize the limb in routine fashion- Can slide horse onto tarp and then move tarp into trailer

Transport in Trailer:- Think about momentum when you brake- If forelimb fracture, face the horse backwards, so hind-end is

at the front of the trailer- If hindlimb fracture, face the horse forwards, as normal

Conclusions:- At some point in your equine career, you will have to manage

an orthopedic (fracture) emergency. - The best you can do is to be prepared to recognize and

diagnose the injury, stabilize the fracture, communicate to the owner the prognosis of the injury, and ensure safe transportation of the horse to a hospital setting.

7