How to Stabilize Equine Fractures in the Field - AAEP · 2018-02-13 · How to Stabilize Equine Fractures in the Field Scott E. Palmer, VMD, Diplomate ABVP (Equine) Appropriate emergency

How to Stabilize Equine Fractures in the Field

Scott E. Palmer, VMD, Diplomate ABVP (Equine)

Appropriate emergency care of horses with unstable fractures is a challenging and life-savingveterinary procedure. Effective treatment requires a thorough understanding of the biomechanicalloads imposed on the fracture site and creation of an external support system that neutralizes theseforces and protects both bone and soft tissues at the fracture site. Author’s address: New JerseyEquine Clinic, 279 Millstone Road, Millstone Township, NJ 08535; e-mail: [email protected]. © 2012 AAEP.

1. Introduction

Emergency stabilization of fractures is an extremelyimportant procedure for veterinarians to perform inthe field. In some cases, external stabilization ofthe fracture may be the definitive treatment. Inother cases, appropriate field stabilization of thefracture enables safe transportation to a facility fora surgical procedure that will achieve anatomic re-duction and compression of the fracture, or, in othercases, ensure survival of the patient. Improperemergency care may limit treatment options andeven endanger the life of the patient. The objectiveof this presentation is to present clinically acceptedtechniques to stabilize common fractures of thehorse.

2. Materials and Methods

Evaluation of the Fracture Patient

Successful management of unstable fractures in thefield involves a combination of clinical assessment,appropriate medical treatment, stabilization of thefracture, and careful and prompt transportation to afacility equipped for fracture repair. Most equinefractures cannot be definitively treated in the fieldand benefit from transportation to a clinic or referral

facility. A horse with an unstable fracture is usu-ally anxious and painful as it attempts to bearweight on the injured limb.

Clinical AssessmentClinical assessment begins with evaluation of thegeneral condition of the horse, the location and de-gree of injury, and an initial determination whetherrepair of the fracture is feasible. Specifically, thisexamination should address the following concerns:What is the overall assessment of the horse’s con-dition and temperament? If the horse is painful oranxious, sedation and analgesic medication shouldbe administered promptly. Is the patient able tobear weight on the injured limb? Is the skin intact?What is the level of the injury? Is the limb unstable?If the limb is unstable, a splint or cast should beapplied to the injured area before performing a ra-diographic examination or transporting the patient.Finally, after consideration of the nature and loca-tion of the fracture, the available medical resourcesand the wishes/expectations of the owner, shouldthis horse be euthanized?

Although acute unstable fractures of horses areusually obvious, it is important to consider the pos-sibility of occult fractures when performing the clin-

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NOTES

Orig. Op. OPERATOR: Session PROOF: PE’s: AA’s: 4/Color Figure(s) ARTNO:

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ical examination. For example, kick wounds of theforearm proximal to the carpus may be accompaniedby a nondisplaced fracture of the radius. Horseswith this type of fracture often will be more lamethan would be expected for a typical laceration.These fractures may respond favorably to conserva-tive management and usually do not require splint-ing, but practitioners should have a high index ofsuspicion when evaluating the injured horse, partic-ularly if a significant lameness is present. Occa-sionally, nondisplaced fractures may be difficult todetect on the initial radiographic examination, butwill be visible on a follow-up study performed sev-eral days later. Practitioners are well advised tobe conservative when making recommendations forthe treatment of horses whose degree of lameness isnot consistent with the clinical and/or radiographicfindings.

It is also important for practitioners to appreciatethe clinical difference between nondisplaced medialand lateral condylar fractures of the metacarpus/metatarsus. Nondisplaced lateral condylar fracturesin which the fracture line clearly communicates withthe lateral cortex of the bone represent a relativelystable situation with a good prognosis for surgicalrepair. Nondisplaced medial condylar fractures orlateral condylar fractures that spiral into the medialcomponent of the diaphysis of the bone represent amuch more serious fracture. These fractures canpropagate into a potentially catastrophic completefracture and should be splinted as for unstable level2 fractures as below. Medial condylar fractures arecandidates for plate fixation and recovery in a pool,if available. During an emergency situation, it is

important for the practitioner to communicate theincreased risk of this type of fracture to the horseowner/trainer, since there is no way to guaranteethat these fractures will not develop into completefractures, even if properly splinted or placed in acast. Fractures of the horse can be grouped into 4levels of the fore and hind limbs with recommenda-tions for external support that are specific to eachlevel (Fig. 1).

Prognosis for Unstable Fractures

In all cases, closed fractures have a better prognosisfor repair than do open (compound) fractures. Sim-ple fractures similarly have a better prognosis thando comminuted fractures. Except as noted abovewith medial condylar fractures, nondisplaced frac-tures generally have a better prognosis for repairthan do displaced fractures. The prognosis for un-stable level 1 fractures varies with the degree ofbone comminution and specific bone involvement.For example, simple fractures of the pastern have agood chance for survival, whereas severely com-minuted fractures have a decreased prognosis forsuccessful repair. The same is true for proximalsesamoid bone fractures and condylar fractures ofMc3/Mt3. Horses with traumatic disruption of thefetlock require fetlock arthrodesis, and their prog-nosis for successful repair is variable according tothe degree of soft tissue injury present.1

Level 2 (mid-diaphyseal) fractures of the thirdmetacarpal and third metatarsal bones have mini-mal soft tissue coverage and are often open due toexternal trauma or penetration of the skin by theedges of the fractured bone, leading to a poor prog-

Fig. 1. Fractures of the horse can be grouped into 4 levels of the fore and hind limbs with recommendations for external support thatare specific to each level.

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nosis. Unstable fractures of the carpus and tarsushave a poor prognosis for athletic soundness butmay be salvaged in some cases for breeding.

In general, the prognosis for level 3 fractures inadult horses is poor, although fractures of the ulnaare often repaired with a good prognosis. Radialfractures typically seen in foals may be amenable torepair with internal fixation.2 Complete diaphy-seal fractures of the tibia may be successfully re-paired in foals, but diaphyseal fractures in adultshave a poor prognosis.3

Level 4 fractures that involve disruption of thediaphysis of the humerus in adult horses have a poorprognosis for a successful outcome. In foals andyearlings, some humeral fractures can heal withoutsurgery. Successful repair of humeral fractures infoals and yearlings that do undergo surgery is morelikely than similar procedures in adults, unless ra-dial nerve damage is present.4 Simple fractures ofthe neck of the scapula that are repaired with inter-nal fixation may have a good prognosis for athleticfunction, but comminuted fractures of the glenoidor the neck of the scapula have a poor prognosis.Fractures of the scapula spine have a good progno-sis.5 Diaphyseal fractures of the femur in adulthorses have a grave prognosis for repair. Diaphy-seal femoral fractures in foals younger than 3months of age have a guarded to fair prognosis forsuccessful repair, but distal physeal femoral frac-tures in foals have a guarded prognosis.6 Pelvicfractures are uncommon in the horse. Overall,the survival rate for pelvic fractures is 50% to 70%.Whereas fractures of the tuber coxae have a goodprognosis for athletic activity, pelvic fractures thatinvolve the articular surface of the coxofemoral jointhave a 20% chance for athletic soundness.7

Initial Stabilization of the Fracture Patient

Medical TreatmentDepending on the temperament of the injured horse,sedation (often in combination with a tranquilizer)is a priority. The goal is to achieve relaxation andpain relief without ataxia. The first choice for se-dation is xylazinea (0.2 to 0.5 mg/kg IV), due to itsminimal cardiovascular side effects and its excellentanalgesic effects for deep skeletal pain.8 Butor-phanolb (0.02 to 0.03 mg/kg IV or IM) or detomidinec

(0.005 to 0.02 mg/kg IV or IM) may be added toextend the duration of sedative/analgesic effect, butcare should be taken not to induce ataxia. It isbetter to start with a minimal dose and add supple-mental treatments only as necessary. Althoughshock is a rare consideration with most acute frac-tures, excessive blood loss or fatigue, particularlyin cases of extreme exertion or high temperatures,may result in compromised perfusion that will re-quire appropriate fluid therapy. Hypovolemic pa-tients initially may be treated with 10 to 20 mL/kgof IV fluids, followed by critical patient assessment.9

If a compound fracture is present, or if there is signif-

icant soft tissue trauma associated with the fracture,broad-spectrum systemic antimicrobial medicationis indicated in conjunction with nonsteroidal anti-inflammatory therapy.

Concepts and MaterialsAn effective splint must provide rigid support toneutralize, as much as possible, the forces acting onthe fracture site that can damage the fracture sur-faces as well as adjacent soft tissues. When a frac-ture occurs between the origin and insertion of amuscle, that muscle no longer has an intact skeletalframe over which to act and often engages in anaction different from its intended function.10 Forexample, the flexors of the forelimb act as adductorsof the distal limb in the presence of an unstablefracture of the radius. Under such circumstances,muscle contraction creates unphysiologic loading ofthe fracture site that can exacerbate the degree ofinjury, complicating or eliminating options for suc-cessful surgical repair.

Materials required for proper immobilization ofdistal (level 1) fractures are sufficient bandage ma-terials (2 to 4 rolls of cotton, 4 gauze bandages,2 ACE bandages, Elasticon�, and duct tape) to cre-ate multiple bandage layers and two 18- to 24-inchlengths of PVC splints. PVC splints may be madeby longitudinally splitting conventional 4-inchPVC pipe into thirds and smoothing the edges witha hoof rasp before incorporating the splints into thebandage. The ends of the PVC pipe may be coveredwith Elasticon tape to prevent sharp edges frominjuring soft tissues. Fiberglass cast materialh mayalso be used to provide increased support. If fiber-glass cast material is used for support, practitionersshould wear examination gloves coated with a thinlayer of K-Y jelly to facilitate application and smooth-ing of the cast material and to prevent accumulationof cast adhesive on the hands during application.For extended splints, any rigid strut, such as abroom or pitchfork handle, board, or metal bar canbe incorporated into the bandage to provide rigidsupport. Splint lengths of 36 inches (from groundlevel to the elbow) are required to stabilize level 2fractures of the forelimb or to fix the carpus in ex-tension in adult horses. Board splints approxi-mately 5 feet in length are required to provideextended lateral support for more proximal frac-tures of the thoracic and pelvic limbs of maturehorses.

Thoracic Limb Fractures

Level 1Unstable fractures of the phalanges, proximal sesa-moid bones, and distal metacarpus are managedwith a cast or a padded bandage and dorsal splint toalign the dorsal cortices of the bones of the digit in astraight line to neutralize bending forces at the frac-ture site and protect the soft tissues from further dam-age. This bandage/splint combination should extend





from the distal carpus to the toe. The Kimzey LegSaver Splinti is a commercial splint that can beeasily applied over a padded bandage to stabilizelevel 1 fractures and is particularly useful for treat-ing horses with disruption of the suspensory appa-ratus (Fig. 2). It is helpful to have an assistantsuspend the injured limb by holding it above thecarpus to achieve alignment of the bones of the digitin a straight line while the splint is applied. Itis important to apply the splint/cast over minimalpadding when stabilizing level 1 fractures to achieveproper alignment of the bones of the digit. Thickpadding allows for excessive movement of the endsof the fracture within the bandage when the horseputs weight on the limb.

Level 2Fractures of the mid forelimb (distal radius to mid-metacarpus) are best stabilized with a Robert Jonesbandage that incorporates caudal and lateral splints.The Robert Jones Bandage is created with multiplelayers of cotton padding (approximately 1 inch thick)that is compressed with gauze and Elasticon ban-dage (Fig. 3 and Fig. 4). The diameter of the fin-ished bandage should be approximately 3 times thediameter of the limb at the fracture site.10 Thesplints are secured to the surface of the Robert Jonesbandage with nonelastic tape such as duct tape andmust extend from the elbow to the ground. Thetape should be applied as tightly as possible to pre-vent movement of the splints when load is applied tothe limb.

Level 3Fractures of the middle and proximal radius areoften open fractures, are more difficult to mobilize,

Fig. 2. A, The Kimzey Leg Saver Splint is a commercial splint that helps to align the bones of the metacarpus and digit to stabilizelevel 1 fractures of the horse. B, Level 1 fractures may also be stabilized with a Robert Jones bandage that incorporates a rigid splintin the dorsal aspect of the bandage.

Fig. 3. A Robert Jones bandage with caudal and lateral splintsis used to stabilize level 2 fractures in the forelimb.



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and have a grave prognosis. Because the majormuscle groups that flex or extend the proximal fore-limb are found on the lateral aspect of the limb,contraction of these muscles in the presence of frac-tures that disrupt the skeletal frame in this areacauses abduction of the limb distal to the fracturesite. This often leads to penetration of bone frag-ments through the skin on the medial side of thelimb. Therefore, the primary goal of splinting level3 fractures is to prevent abduction of the injuredlimb. Foals may be stabilized with a Robert Jonesbandage that extends from the axilla to the toe witha lateral splint that extends up the lateral aspect ofthe chest and lies against the ribcage. Euthanasiais often recommended for adults with this type offracture because of the poor prognosis for successfulrepair.

Level 4Fractures of the humerus, ulna, and the distal scap-ula are well protected by substantial overlying mus-cles and are generally not splinted at the fracture

site (Fig. 5 and Fig. 6). However, horses with frac-tures in this area cannot fix the elbow, which isessential for normal weight-bearing. Horses withlevel 4 fractures are best treated by applying a sim-ple full-leg padded bandage with a caudal splint tofix the carpus. Horses thus supported have im-proved balance for transportation, but they willhave difficulty walking and will require assistancefor loading into the van or trailer.

Pelvic Limb Fractures

Level 1The goal of stabilizing fractures of the phalangesand distal metatarsus in the pelvic limb is the sameas that in the thoracic limb. However, natural flex-ion of the pelvic limb induced by the reciprocal ap-paratus makes application of a plantar splint or castmore convenient to align the solar surface of the footwith the bones of the digit and metatarsus. As inthe thoracic limb, it is helpful to have an assistantsuspend the injured limb from the hock in a slightly

Fig. 4. A Robert Jones bandage with a caudal splint and anextended lateral splint is used to stabilize level 3 fractures of theforelimb.

Fig. 5. A padded bandage with a caudal splint that extends fromthe elbow to the ground is used to fix the carpus and thus supporthorses with level 4 fractures of the forelimb.



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caudal position while the splint is applied. If avail-able, a Kimzey Leg Saver Splint may also be used tostabilize level 1 fractures of the pelvic limb.

Level 2Fractures of the middle and proximal metatarsusare also managed with a cast or a Robert Jones ban-dage with a plantar and lateral splint. The tubercalcis acts as a functional extension of the metatar-sus and provides additional support when incor-porated into a bandage that includes caudal andlateral splints that extend from the point of thehock to the ground. The padding of this bandageshould be somewhat less than that used in the tho-racic limb because it is more difficult to include thetarsus in the bandage, and too much padding underthe splints will make it more difficult to stabilize thefracture.

Level 3Fractures of the tibia and tarsus are more difficultto mobilize and have a grave prognosis in adults.The biomechanical load placed on the reciprocal ap-

paratus in the pelvic limb presents unique chal-lenges to immobilization of fractures in this area.If an unstable tibia fracture is present, flexion of thestifle will occur without flexion of the hock. Thisresults in overriding of the ends of the fracture frag-ments and additional trauma to both the bones andsoft tissue. As in the case of radius fractures ofthe thoracic limb, level 3 fractures of the pelvic limbcreate abnormal abduction of the distal portion ofthe limb, which must be prevented. Foals may bestabilized with a Robert Jones bandage with an ex-tended lateral splint that prevents abduction androtation of the limb and transported to a hospitalfor repair. Euthanasia is often recommended foradults with this type of fracture because of the poorprognosis (Figs. 7 and 8).

Level 4Fractures of the femur or pelvis are protected bylarge muscle groups and are generally not splinted.These horses should, however, be kept quiet andassisted as much as possible when loading or trans-porting to another facility.

Fig. 6. A Robert Jones bandage with a caudal splint is used tostabilize level 1 fractures of the hind limb.

Fig. 7. A Robert Jones bandage with plantar and lateral splint isused to stabilize level 2 fractures of the hind limb.



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Transportation of the Fracture PatientLoading the splinted horse for transportation to aclinic or hospital should be as atraumatic as possi-ble. The trailer or van should be positioned close tothe horse, and the ramp should be positioned on agrade to level the ramp as much as possible forloading. Assistants should be used to help stabilizethe horse when loading.

Adult horses should be placed in a partitioned/confined space in the trailer, restrained with chestor rump bars, and the head should be tied loosely toallow the horse use of the head and neck for balance.In the case of a thoracic limb fracture, position thehorse facing rearward to allow for use of the pelviclimbs to brace when stopping. Horses with a pelviclimb fracture should be placed facing forward toallow for use of the thoracic limbs as a brace whenstopping. Foals should be shipped with the mare,and an attendant may be used to help stabilize thefoal during shipping. Bales of hay may be used toprovide a reduced stall space for an injured foal ifan attendant is not available. Foals will usuallytravel in a recumbent position.

3. Discussion

Appropriate emergency stabilization of fracturesshould provide rigid support of the fractured bonesto minimize trauma of the fracture surfaces andprevent further damage to adjacent soft tissues.Although it may be difficult or impractical to haveall the necessary materials in your vehicle to stabi-lize every type of fracture of the horse, a minimalinventory of emergency support materials should bekept in good condition and be readily accessible.The most common site of injury is the distal extrem-ity, and many injuries are commonly associated witha particular sport discipline. For example, practi-tioners who attend to Thoroughbred racehorsesshould be prepared to adequately splint and supporttraumatic injuries of the fetlock and digit, whichcomprise a majority of potentially catastrophic in-juries in that breed. The successful repair of anequine fracture always begins with emergency carethat incorporates a rigorous application of the prin-ciples described herein. Proper splinting and trans-portation of the fracture patient improves the chancesof successful surgical repair.11 In some cases, thecorrect application of these basic principles will lit-erally be a matter of life or death of the patient.

References and Footnotes1. Bramlage LR. Fetlock arthrodesis. In: Nixon AJ, editor.

Equine Fracture Repair. WB Saunders Co, Philadelphia,PA; 1996:172–178.

2. Auer JA. Fractures of the radius. In: Nixon AJ, editor.Equine Fracture Repair. WB Saunders Co; 1996:222–230.

3. Watkins JP. Fractures of the tibia. In: Nixon AJ, editor.Equine Fracture Repair. WB Saunders Co; 1996:273–283.

4. Nixon AJ. Fractures of the humerus. In: Nixon AJ, edi-tor. Equine Fracture Repair. WB Saunders Co; 1996:242–253.

5. Adams S. Fractures of the scapula. In: Nixon AJ, editor.Equine Fracture Repair. WB Saunders Co; 1996:254–258.

6. Hance SR. Fractures of the femur and patella. In: NixonAJ, editor. Equine Fracture Repair. WB Saunders Co;1996:284–293.

7. Ducharme NG. Pelvic fracture and coxofemoral luxation.In: Nixon AJ, editor. Equine Fracture Repair. WB Saun-ders Co; 1996:294–298.

8. Pippi NL, Blumb WV. Objective tests of analgesic drugs inponies. Am J Vet Res 1979;40:1082.

9. Smith JJ. Emergency fracture stabilization. Clin Tech-niques Equine Pract 2006;5:154–160.

10. Bramlage LR. First aid and transportation of fracture pa-tients. In: Nixon AJ, editor. Equine Fracture Repair. WBSaunders Co; 1996:36–42.

11. Bramlage LR. Current concepts of first aid and transporta-tion of the equine fracture patient. Comp Cont Educ PractVet 1983:564–574.

aAnaSed� Injection, Lloyd, Shenandoah, IA 51601.bTorbugesic�, Pfizer Animal Health, Exton, PA 19341.cDormosedan�, Orion Corp., Pfizer Animal Health, Exton, PA

19341.dRolled cotton, Kendall/Covidien, Mansfield, MA 02048.eBrown gauze, National Health Care, Scottsdale, AZ 85222.fACE Bandage, Jorgensen, Loveland, CO 80538.gElasticon, Johnson & Johnson, Skillman, NJ 08558.hVetcastTM Plus Casting Tape, 3M Animal Care Products,

St Paul, MN 55144-1000.iKimzey Leg Saver Splint, Kimzey Welding Works, Woodland,

CA 95695.

Fig. 8. Fractures at level 3 in the hind limb are supported by aRobert Jones bandage with an extended lateral splint.



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How to Stabilize Equine Fractures in the Field - AAEP · 2018-02-13 · How to Stabilize Equine Fractures in the Field Scott E. Palmer, VMD, Diplomate ABVP (Equine) Appropriate emergency