☻Fracture

FRACTURE

Definition:

Break down of bone continuity

Classification:

I-ACCORDING TO DEGREE OF DAMAGE: -

1-Incomplete fracture: -

A-Green stick fracture: -

It is a type of fracture affects long bones of young animals especially those with rickets. The increased pressure over the convex surface of the affected bone predisposes to fracture.

B-Fissure cracks or fissure lines: -

They are single or multiple fractures lines; parallel or not; of different directions (transverse, longitudinal, or oblique), of traumatic origin and usually affect flat bones like scapula.

C-Splint fracture (Splinter): -

It affects flat or long bone, ensues as a result of gun fire, the bone still intact, and the hole of the gun fire sometimes has cracks around it.

D-Differed incomplete fracture: -

It ensues as a result of neglecting incomplete fracture for a long period

2-Complete fracture: -

A-According to fracture line: -

i-According to number of fracture lines: -

1-Single line fracture: -

It is a fracture that divides the bone into two pieces

2-Multiple fracture or comminuted fracture: -

It is a fracture type where the bone is divided into more than two pieces.

ii-According to site of fracture: -

1-According to the location of fracture line on the bone: -

Fracture can be classified into epiphyseal, diaphyseal, or metaphyseal

2-According to the name of the fractured piece of bone: -

Fracture can be classified into condoiler, supracondoiler, articular, trochanteric, or inter condoiler

iii-According to the shape of fracture line: -

1-Longitudinal

Usually it affects short bones

2-Transverse

Usually it affects long bones

3-Oblique

B-According to fracture fragment: -

i-Overlapped fracture: -

It is a fracture in which the two fragments overlap each other and can be observed in case of oblique fracture

ii-Angled or angulated fracture: -

It is a fracture characterized by angle formation between the two bone fragments

iii-Lateral fracture: -

It is a fracture type in which the two edges of the fractured bone lies lateral to each other

iv-Spiral fracture: -

It is a fracture type characterized by rotation of one bone fragment around its long axis

v-Star shape fracture: -

It is a fracture characterized by presence of cracks around the gunfire giving it star shape

vi-Wedged or impacted fracture: -

It is a fracture a fracture characterized by no displacement with wedging of the two fractured fragments like wedge or like suture of flat bones of skull

vii-Depressed fracture: -

It is a traumatic fracture of flat bone over a cavity leading to displacement of a disc of bone into this cavity, like frontal bone.

viii-Compressed fracture: -

It is a fracture with shortening and thickening of the bone as that with vertebrae

ix-Destructed fracture: -

Fracture characterized by wide separation of the bone fragments due to pulling action of ligament like fracture of patella

II-ACCORDING TO SITE OF FRACTURE: -

As mentioned before

III-ACCORDING TO COMPLICATIONS: -

1-Simple fracture: -

It is pure bone fracture with no complications

2-Compound fracture: -

It is fracture with skin injury (wound)

3-Complicated fracture: -

It is fracture associated with injury to nerve (like radial paralysis), artery or vein, opening of a joint, opening of a body cavity (like chest)

Causes:

I-EXITING CAUSE: -

1-Extrensic forces: -

A-Direct violence: -

Like falling from high places, car accidents, violent beating of an animal with strong stick

B-Indirect violence: -

The site of trauma is far from the site of fracture as falling on leg with fracture of the back (compression) or pelvic bones, twisting of hand with fracture of shoulder bones,

2-Interinsic forces: -

A-Severe muscular traction during racing

B-Bone diseases: -

Cancer, rickets, or osteomalasia

II-PREDISPOSING CAUSES: -

1-Heriditary: -

2-Age: -

The incidence of fracture is higher in young animals, and heavy animals

3-Sex: -

During sexual intercourse, females are more susceptible to pelvic fracture, while males are more susceptible to fracture of hind limb

4-Nuteritional: -

Low calcium and phosphorus, high vitamin A, high fluorine, and high carbohydrate with obesity

5-Hormonal: -

Hyperthyroidism increases blood Ca and P and reduces them in bone

6-Aim of animal use: -

Galloping, jumping, drafting horses are more susceptible to fracture than show or fantastic horses

7-Nature of land: -

Fracture is less frequent on soft land and its incidence increases on slipary or hard lands

8-Animal temper: -

Fracture is less frequent in calm animals and more frequent in vicious animals

9-Animal condition and diseases: -

Cancer or skinniness predisposes to fracture 

Symptoms:

I-LOCAL SIGNS: -

1-Pain, restlessness, and laying down         2-Swelling                          3-Function impairment

4-Abnormal position of bone          5-Abnormal sound (crepitate)          6-Abnormal motility

7-Albiumenurea

II-SYSTEMIC: -

Traumatic fever and anorexia

Diagnosis:

1-History

2-Clinical examination (local symptoms and crepitation)

3-Radiography for small animals or appendages of large animals

Healing:

1-Pathologic classification: -

A-Soft callous: -

i-Stage of hematoma (1-3 days)                        ii-Stage of tissue granulation (5 days)

iii-Stage of ostoid tissue formation (5-7 days)

B-Hard callous: -

i-Stage of consolidation (3-5 weeks)                 ii-Stage of osseous tissue formation (6 months)

iii-Stage of remodeling

2-Clinical classification: -

A-Temporary callous

B-Soft callous: -: -                    

Bleeding occurs during fracture with accumulation of inflammatory exudates leading to swelling. The fluid is reabsorbed, and blood under goes clotting with fibrin net formation. Later on angioblasts and fibroblasts appear for granulation tissue formation from the periphery toward the center. This process is associated with condrogenic changes (formation of cartilage) and ostoid tissue formation by osteoblasts with calcium deposition.

C-Hard callous: -

It starts with consolidation and characterized by calcium deposition under control of blood calcium level, and gypsona can be removed 3-5 weeks later. Osseous tissue formation and remodeling occur during this stage with union of the bone fragments, conversion of ostoid tissue to osseous tissue, and formation of haversian system (it lasts 6 months). Osteoclasts lyses the external and internal callous with precipitation of calcium form outer to inner parts of the intra-fragmental callous.

Factors affecting healing: -

1-Age: -

The younger the age the faster the healing (2-3 ws in young and 3-5 ws in old animals)

2-Individuall variation: -

3-Nutrition: -

Qualitative or quantitative reduction in food ingredients prolongs healing time

4-Cause: -

Traumatic injuries is characterized by temporary hematoma followed by rapid healing, while infection of fracture site causes destruction of the granulation tissue with prolongation of healing time.

5-Site of fracture: -

Epiphyseal fracture of spongy bone heals faster than fracture of compact bone

6-Shape of fracture: -

Oblique or longitudinal fracture is better than transverse fracture, also single smooth fracture is better than multiple fragmented granulated fracture.

Non union and delayed union of fracture: -

1-Wide separation                                               2-Incarciratin of soft tissue between fragments

3-Some diseases (rickets or osteomalasia)         4-Infection or osteomylitis

Prognosis: -

1-Age and species variation: -

Old animal has bad prognosis due to

-Difficult reduction of fracture            -Difficult immobilization

-Prolonged healing                               -Increased possibility of complications by movement

-Stiffness of joints and cartilaginous degeneration due to prolonged healing

-Muscular atrophy and fatigue due to prolonged healing

-Skin necrosis and ulceration due to prolonged healing

-Soft tissue edema due to prolonged healing

-High possibility of reactions in the sound limbs (tendonitis, arthritis, and deformity)

-Deformity of fractured limb

2-Aim of use: -

Draft and racing horses cannot be treated but valuable animals can be treated and used for breeding

3-Economic value of the animal and cost , and relation between animal and owner: -

Low price animals should be condemned if the cost of treatment is high, while pets are treated whatever the cost. Pets and horses should be treated wt ever the cost

4-General condition of the animal: -

a-Fracture site and shape of fracture: -

Forelimb fracture has better prognosis than hind limb, and fractures below carpus and tarsus is better than higher fracture due to easier fixation.

b-Sex of the animal: -

Female fractures have better prognosis than male fracture due to quietness of the female.

c-Duration: -

The more recent the fracture the better the prognosis

d-Complications: -

Simple non-infected fracture has better prognosis

Treatment:

1-Primary treatment: -

A-Prevention of shock due to pain by analgesics

B-Prevention of further damage due to movement

C-Prevention of change of simple fracture to compound due to movement

2-Secondary treatment: -

A-Reduction of fractured bone to approximate normal position: -

It should be done as soon as possible before numbness and pain, spasm, and swelling, as pain causes muscular spasm.

Technique:

These steps should be done after good straining of the animal with application of general anesthesia as local analgesia retard healing. The aim of anesthesia is to relieve pain, and induction of muscular relaxation. Later on extension and counter extension by an assistant should be done to bring the bone fragments in one level. Finally X-ray should be done to ensure the normal positioning of bone fragments.

Types of reduction:

i-Closed reduction: -

It is performed with the skin closed (intact skin)

ii-Open reduction: -

The bone fragments are reduced to normal position surgically with inscising the skin aseptically

B-Fixation and immobilization till complete union of bone: -

The bone fragments and the joints upper and lower to the fractured bone should be fixed till complete union of fracture

Types:

i-External fixation: -

The joints upper and below the fracture should be fixed, and sometimes all the limb is fixed

Advantages:

-Cheap and easy method

-It doesn’t need high experience or complicated equipment

-There is no possibility of infection

Disadvantages:

-Pressure necrosis

-Joint problems and stiffness, and muscular atrophy due to prolonged fixation

Types:

1-Ordinary splints: -

It must be cheap, light weight, malleable, and has length greater than the distance between the two joints, like metal, wood, leather, or even cartoon in birds or pets. At least two splints (medial and lateral) are needed for proper fixation.

Application:

-The joints above and below the fracture should be involved and fixed, and sometimes the entire limb is fixed.

-Application of enough cotton padding to avoid direct pressure on skin and subsequent necrosis and gangrene, and to make the animal more comfortable, but very thick padding decreases the fixation. Cotton should be inserted between claws or fingers, and should be at levels beyond the splint.

-Splints are applied medial and lateral to the limb

-A gauze tapping should be applied over the splints

2-Casts: -

-Example of casts is the Gypsona or plaster of paris. Other types of casts are plastic or fiberglass casts and they are stronger and not affected by moisture but  they have no pores leading to heat stasis and sweat stasis with final maceration of the skin.

Advantages:

-Cheap, easily applied, and has no local complications

Disadvantages:

-Affected by moisture and need long time to reach its maximum hardness (24 hours)

Application:

-Application of bandage by padding with cotton and tapping with gauze as mentioned before

-Application of gypsona, then leave the animal for 0.5 hours to hardening of gypsona

Postoperative care:

-The cast should be observed for cracking, presence of discharge (color), odor, and swelling

3-Thomas tube: -

It is a metal tube of two rings (upper wide with a diameter 1 inch more than the thigh, and lower narrow), and two lateral splints longer than the limb. A modified Thomas tube with bent side splints is used for the hind limb.

ii-Direct skeletal fixation: -

This method is a mixture of external and internal methods of fixation. It is not applied directly on bone, and the bone itself is fixed externally without incising the skin by using pins that pass percutaneous from bone cortex to the opposite cortex and the pins are fixed outside by frame. The pins should be sterile, and of non-corrosive or ionized substances like stainless steal, platen, or cobalt nickel. Examples are standard splint, Keurs slimmer splint, and Ehmar splint.

Advantages:

-No joint fixation thus avoids complications of joint affects and muscular atrophy

-No hindrance of circulation

Disadvantages:

-High incidence of infection

Application:

Under aseptic condition, the pins are driven percutenously into muscles, perosteum, and the two cortexes. It is better to drive the pins in two different angels for better fixation.

ii-Internal fixation: -

Direct fixation applied to bone itself

Advantages:

-Better method because it fixes the bone itself without involvement of the joint

-It produces accurate reduction as the skin and muscles are opened

-It has no circulatory hindrance or pressure atrophy

Disadvantages:

-High incidence of infection and inflammation, and destruction of bone marrow

-Pressure of the splint on bone

Used materials:

-From clinical point of view it should be of high strength, non-corrosive, not rusting, and not ionizing

-From economic point of view it should be cheap like stainless steal (it is the best), ceramic, nickel, or cobalt

Types:

1-Extramedullary: -

a-Screw pin fixation: -

Indications:

-Fractured extremities, head of bone, neck, or condoiles

Technique:

-Control of the animal

-General anesthesia and aseptic precautions

-Open reduction of fractured bone

-Drilling of bone fragments and screw pining through the entire thickness of the fractured fragments

-Closure of wound in layers

-Removal of the pin after complete healing

b-Circular wiring or bone suturing: -

Indications:

-Treatment of fractured flat bones (jaw, scapula, etc…)

Technique:

-Control of the animal

-General anesthesia and aseptic precautions

-Open reduction of fractured bone

-Drilling of bone fragments with suturing of fragments with simple interrupted wiring by stainless steal wire

-Closure of wound in layers

-Removal of wire after complete healing

-This method can be used with other methods like screw pining

c-Bone plating: -

This method can be applied by using metal plate that has the same bone convexity and fixed with 4-6 pins

Indication:

Diaphysial fracture of long bones

Disadvantages:

-Exposure of large area of the bone and tissue that predispose to infection

-The plate is applied directly on the bone that predisposes to necrosis

Technique:

-Control and general anesthesia

-Aseptic technique guide

-Open reduction of the bone fragments, exposure, and fixation by plate and pins

-Closure of the wound in layers

2-Intramedullary pinning: -

Fixation is done here through the medullary cavity of the bone. It can be applied to diaphyseal fractures of long bones but metaphyseal fractures are treated by screw pins

Advantages:

-Proper reduction and fixation of the bone fragments

-Joint, muscles, and blood supply not affected

Disadvantages:

-Bone marrow destruction

-Infection and osteomyelitis

Types of pins:

-Steinman pin that is straight and round in cross section (The best)

-Keutschner pin that is straight and triangular in cross section

-Rush pin that is bent near its wide end

Indications:

Fractured long bones, but cant be used for comminuted fractures, multiple fractures, infected fractured, or metaphyseal fractures

Technique:

-Control and general anesthesia

-Aseptic technique guide

-Open reduction of the bone fragments

-Insertion of the pin along the bone through medulla, and the excess length is removed by saw, or the pin is inserted in retrograde manner

3-Bone grafting: -

It can be used when here is no union of bone fragments or for comminuted fractures

a-Auto bone grafting: -

A piece of spongy bone is removed for healthy bone of an individual, fragmented, and transplanted to the fracture site of the same individual

b-Homo bone grafting: -

The same is performed for an animal to another animal of the same species

c-Hetero bone grafting

The same is performed for an animal to another animal of another species

Treatment of compound fractures: -

-The principle here is to treat the fracture and the wound as soon as possible with control of infection

-Fixation, internal and direct skeletal fixations have no problem for the wound, while external fixation interfere with monitoring of the wound, so 8-Figure gypsona should be applied to leave a window for wound monitoring

-The wound is treated as usual through the window in the gypsona

C-Preservation of normal function of muscles, tendons, and joints: -

Complications of fractured: -

1-Pressure necrosis, muscular atrophy, and joint stiffness due to pressure of the fractured fragments

2-Damage of artery or vein due to movement of splint

3-Improper reduction and fixation

a-Gangrene due to direct pressure of splint on skin or tissue, impairment of circulation, or thrombi of the main blood supply. Signs of gangrene appear 24-48 hours later on in the form of;

-Local signs: - Bad odor, swelling, and greenish discharge,

-Systemic reaction: - Fever and anorexia

Treatment should be applied as soon as possible by removal of splint and application of hot antiseptic fomentations to enhance circulation, but if gangrene appeared, amputation will be the main treatment.

b-Faulty callous formation and can be prevented by proper fixation

c-Failed callous formation due to low calcium level, infection, improper fixation

d-False joint due to soft tissue between the two fragments with outer fibrous connective tissue connecting the two fragments. Cartilage may be formed beside the soft tissue, it can be treated by removal of fibrous connective tissue, soft tissue, and cartilage, refresh the bone surfaces by scraping, then make proper fixation

Conclusion:

-Fractures of the scapula and pelvic bones: -

Can’t be treated

-Fractures of the shaft of femur and humorous: - It can be treated by intramedullary bone pining, bone plating, or direct skeletal fixation

-Fractures of the extremities of femur and humorous: - It can be treated by internal fixation by screw pin

-Fractures of extremity of radius, ulna, tibia, and fibula: - It can be treated by screw pining, internal fixation, or external fixation (Thomus or modified Thomus)

-Fractures of shaft of radius, ulna, tibia, and fibula: - It can be treated by intramedullary bone pining, direct skeletal fixation, splint and cast, or external fixation (Thomus or modified Thomus)

-Carpus, tarsus and downward: - It can be treated by cast or splint

-Skull and flat bones: - It can be treated by suturing; interalveolar wiring pf check teeth, bone plating, direct skeletal fixation for ramus; and wiring, bone pinning, or screw pining for  factiures of mandibular body