SPECIAL FRACTURES. The Cranium.Frac tures of the bones of the cranium are chiefly found in the horse. The crest of the occi pital bone is fractured by direct violence. In a simple fracture there is great swelling and pain in the region of the poll. Considerable cedema of the head is seen some days after the accident. Compound, fractures are more common in this region.
Treatment in a simple fracture consists in keeping the head as much as possible at rest, feeding the animal from a high manger. In the case of a compound fracture the fragments must be removed, provision made for drainage, and the wound treated on the usual lines. Fracture of the occipital at its base is the most serious of cranial fractures and is always fatal. This is caused by the animal falling over on the back of the occiput. The base of the sphenoid may also be fractured at the same time.
The Facial Bones.Any of the bones of the face, including the nasal bones, may be fractured, generally directly. The common symptoms are pain, swelling, and discharge of blood from the nostrils. In fracture of the facial portion of the frontal bone the prognosis is good. Fracture of the orbital process is more serious, and not always easy of diagnosis. The swelling may be considerable, and the function of the eye interfered with. In a case of a compound fracture any displacement may be reduced by a suitable lever. In a simple fracture over the frontal sinus the depressed bone need not be interfered with, but when the fracture is com pound the depressed portions should be elevated and all loose pieces of bone and damaged soft tissue removed. The wound is then treated by the open method.
Fractures of the nasal bones due to direct violence are commonly seen in the horse. Either one or both bones may be fractured. The symptoms are local depression, bleeding from the nose, and if there is considerable depression, some noise will be made in breathing. If the fracture is simple and situated near the nasal peak, the depressed bone may be elevated by a suitable lever introduced up the nostril, care being taken not to injure the turbinated bone. If the fracture is compound this elevation may be made through the wound. In some cases it may be necessary to trephine and raise the depressed pieces, at the same time using every precaution against injury of the turbinated bone.
Fractures of the premaxillary bone are most common in the horse, and are caused by falls and kicks. The fracture may be confined to the external process, sometimes to the alveolar portion involving one or more incisors, or the fracture may be transverse to the body. Dia gnosis in these cases is not difficult. Under neath the local swelling the position of the fractured bone can be felt. There is more or less backward movement of the part, and the incisors are generally displaced backwards. In a transverse fracture there is marked deformity, in addition to backward displacement of the incisors. Replacement can generally be effected by hand, although considerable force may be necessary. The fragment may then be fixed in position by wiring the incisors. Sometimes the fracture involving the alveolar portion is an open one, with one or more of the incisors detached. Such cases should have the loose teeth as well as the fractured portion removed. A compound transverse fracture is a more serious matter, and may end in deformity and an excessive callus. Prognosis and treatment should be then carefully considered. Com pound superficial fractures in the interdental spaces are occasionally found in young horses when being broken, due to injury from bits. The fractured pieces are slow in exfoliating, and it may be necessary in some cases to remove them surgically. Otherwise these accidents call for no special treatment.
Fractures of the lower jaw are most frequently seen in the horse, sometimes in the dog, in both cases due to external violence, such as kicks and falls. In the horse they are occasionally due to dental operations. I have seen a frac ture of the branch near the angle, from an attempt to punch out a diseased molar. Frac ture from external causes may occur at the neck, in one or both branches, or at the anterior border. Fractures of the coronoid process are rare. Simple fracture of one branch of the neck of the lower jaw is not always easy of diagnosis, even when complete. There is pain, swelling of the jaw with great difficulty of mastication, but mobility and crepitus may be absent. If the fracture is compound, it renders diagnosis easy, but of course adds to the gravity of the case. In fracture of the body of both branches at the neck, the chin and incisors drop they are mobile, and crepitation can be detected. In the horse subcutaneous fractures of one branch or of the neck unite completely with merely feeding the animal on soft food. Compound fractures are grave, and fracture of the coronoid process much more so. The treatment of double fractures, either at the branches or neck, requires considerable me chanical ingenuity to immobilize the parts and keep them in apposition. Wedge-shaped splints of various materials fitted into the maxillary space are generally recommended. These, carefully padded, are retained in position with suitable straps or tapes, passed over the animal's face and neck. In other cases wiring some of the teeth together with copper wire will keep the parts in apposition. Immediate wiring of the fractured bones may be worth a trial in some cases, especially if the subject be a dog. In compound fractures the wound should be enlarged, if necessary, and all loose tissue, loose teeth, and pieces of bone removed. An attempt must be made to render and keep the wound free from sepsis. The cavity should be disinfected with pure carbolic and the open ing packed with suitable material renewed when necessary. Even with the best attention and care suppuration follows, and with it necrosis and sequestra. Then we have, as a termination to the fracture, an excessive callus, and one or more sinuses. Fractures of the lower jaw of the ox are rare, but they are of serious import owing to the anatomical arrangements of the branches at the symphysis.
Fractures of the Vertebrm.In the horse fractures of the cervical vertebrae occasionally occur from external violence or extreme muscular action. If the phrenic nerve be involved the accident is followed by sudden death. More frequently some of the processes are fractured, leaving the bodies intact. These fractures give rise to regional swelling, pain, and distortion of the neck.
Fracture of the dorsal and lumbar vertebrae is more common, and fracture of the pro cesses of these bones apart from their bodies is rare, except in the region of the withers. These fractures may be caused by collisions, by suddenly stopping, by rearing and jumping, and by kicking—a comminuted fracture of the second lumbar vertebra was found in a riding horse -which kicked out with both legs whilst the rider was down tightening the saddle girths —but the most frequent cause is from excessive muscular action when a horse is cast in the stall, or cast for an operation. As the result of casting, any of the lumbar and dorsal vertebrae may be fractured, usually the two last dorsal or the first three lumbar. Fracture is brought about by arching the back, the animal's head is carried towards the sternum, the legs being fixed either against the partition of the stall or in the hobbles. This is followed by a power ful contraction of the longissimus dorsi and the great psoas muscles. The pressure on one or more of the vertebrae in question may be so great as to cause a comminuted fracture of the body of the bone. In some instances this frac ture is brought about by lateral flexion of the back and loins, and lifting of the hind quarters clear of the ground. Certain conditions favour these fractures, such as old age, anchylosis, disease of the bone, and the smooth surface on which the animal may be cast favouring flexion of the loins. Want of exercise appears in some cases to favour broken back. Horses which have been rested for lameness, or stallions that have not been used for service and kept at rest for an indefinite period, often break their backs when put down for operation. These accidents generally occur when the animal is laid on its side, rarely when on its back. Fractures of the body of one of the vertebrae in question are generally followed by displacement of the broken fragments and injury to the spinal cord, or haemorrhage into the spinal canal and paraplegia. If the accident should occur during an operation, a dull snap or crunch ing may be heard during a violent struggle of the animal, which immediately becomes passive, and begins to sweat on the hind quarters. In other cases the accident is not suspected until the hobbles are removed and the horse is found unable to rise.
In some cases it would appear that separa tion of the fracture of the body is deferred. In these cases the fracture may only be a fissure. The animal is able, with assistance, to rise and walk some distance with more or less knuckling of the hind fetlocks. Cases are recorded in which animals did work for some time after the injury was inflicted. I have known a hunting horse walk four miles after the third lumbar vertebra was fractured in a jump. Another was ridden a day after such a fracture was infficted from casting in a stall. With a van mare, which fell on ice, separation of the fracture and paralysis did not occur until nearly a fortnight after the accident, the animal having been kept at rest in the meantime. In cases of broken back, with the exception of the above symptoms, together with loss of sensation in the hind quarters, and flaccidity of the tail, examination gives negative results. Crepita tion, swelling, and pain are not observable. When paraplegia is complete the case is hope less, and the animal should be slaughtered as soon as possible. If the horse be able to stand, it is probable that the vertebra is only fissured, and some slight hope of recovery may be enter tained, as we have post-mortem evidence that horses do sometimes recover from a broken back. When the history of the case is obtain able no difficulty is experienced in forming a correct diagnosis of broken back. Where, how ever, there is no history, and a horse is found with paralysis of the hind quarters, the possi bility of other causes such as hmmoglobinuria, sprain of the muscles of the loins, or concussion of the cord should be kept in mind.
Treatment, in case of broken back, must be to keep the animal at rest, if possible, and from lying down until such time as the bony union is likely to be completed. Whether the animal should be placed in slings or not depends on its temperament, and should be left to the discretion of the veterinary surgeon.
Prevention of Broken Back.A horse should never, if possible, be cast for an operation with out a twelve hours' abstention from food. If long out of work it should be exercised to point of fatigue daily for a few days previous, and cast on a soft bed of deep straw. The head and neck should be kept extended when down by capable assistants, lateral flexion should be prevented by an assistant sitting on the upper quarter, and the hobble chain should not be locked too short, so as to diminish as much as possible the"point d'appui"to the limbs.
Fracture of the sacrum is not common. In the horse and cow it is caused by external violence. Compound fractures of the spines of its vertebral segments are prone to be followed by suppuration and burrowing of the pus be tween the muscular planes of the croup. Frac tures of the body lead to paralysis of the tail and rectum, and sometimes paralysis of the hind limbs. Diagnosis is not difficult. The local swelling, paralysis of the parts mentioned, and an examination per rectum are sufficient to satisfy the practitioner as to the existence of the fracture. In cases where paralysis is complete recovery is hopeless.
Fractures of the coccygeal vertebra are seen mostly in dogs and bovines, and are not in frequently crushed and open fractures. When the first vertebrae are fractured paralysis of the tail results. In the case of simple fracture there is local pain, some swelling, limpness of the tail, and crepitation, which can be felt and sometimes heard.
Fracture of a caudal vertebra frequently terminates in a false joint. In treating such fractures any bandaging to the tail should be carried out with the greatest precaution, as the caudal blood supply is so easily curtailed or arrested that necrosis may occur without precursory symptoms. Compound fractures of the tail are liable to be followed by trouble some abscesses and sinuses, and when possible should be treated by amputation.
Fractures of the Ribs.Fractures of the ribs are seen in all animals. Simple transverse fractures are most common in horses and cattle as the result of external violence, or sometimes, as in the case of the first rib of the horse, from muscular action. In many cases simple frac tures from external violence are incomplete and give rise to no disturbance, and require no further treatment than rest. It is rare that a fracture is limited to one rib, and as a rule the sternal ribs are more liable to fracture than the asternal, which are more mobile. Union is generally associated with a considerable amount of callus, which is found more abundantly on the inner side of the rib. Fracture of the first rib in a horse gives rise to lameness simulating radial paralysis owing to the nerve supply of the muscles of the limb being involved in the injury. There is inability to extend the leg. In instances where the violence is severe and direct, many ribs may be broken and the frag ments driven inwards, wounding the pleura, lung, or diaphragm. Then in addition to pain over the seat of fracture, there may be rapid respira tion, cough, and a discharge of blood from the nose. Crepitus and mobility of the parts can not always be detected. In a complicated fracture, involving penetration of the chest, the consequences are much more grave. The injury may be associated with effusion of blood into the pleural cavity, due to rupture of the costal artery; the ingress of air to the pleural cavity through the wound, or through the lungs from a laceration by a fragment of a rib. Sub cutaneous emphysema may also be present, and later traumatic pleurisy, also suppuration of the wound complicated with necrosis of the rib.
Treatment of complicated fractures of the ribs consists in removing foreign bodies and detached fragments of bone, arrest of haemo rrhage, disinfecting the wound, and endeavour ing to convert an open fracture into a closed one. Should the pleural cavity not be actually opened, every care must be exercised in the above practice against penetrating into the chest, and every precaution should be adopted to prevent sepsis which may be followed by necrosis and costal fistulae.
Fractures of the Pelvis.Fractures of the pelvis are common in horses and cattle due to such external violence as falls on ice and smooth pavements, and to striking against the sides of narrow doorways. The most common and least important of these injuries is the fracture of the external angle. Fracture of the internal angle is occasionally found, but fracture of its shaft is more common, and is an accident of great gravity. The tuberosity of the ischium may be fractured, also the shaft, or the ramus. The pubis may also be fractured through the body or through the ramus. Fractures may also occur through the cotyloid cavity, through the rami of ischium and pubis parallel to the symphysis pubis, or through the pelvic sym physis itself.
Symptoms of pelvic fracture are lameness, which varies greatly in degree, crepitation, mobility, and deformity. In making an examina tion for a fracture of the pelvis one hand should be placed on the external angle of the ilium, and the other on the tuberosity of the ischium, an attempt being made to move the quarter from side to side. A manual examination can also be made through the rectum, and in the mare and cow, through the vagina. If the animal be down the ear can be placed on the quarter, and at the same time the external angle of the ilium should be moved, or the affected leg put through movements of flexion and abduction. Crepitation is absent in frac ture of the angle of the ilium, but can be felt, especially per rectum, when the shaft is broken and the animal is moved slowly. In fractures of the ischium, crepitation can be felt by the rectum or vagina, on movement of the affected limb. With fracture of the cotyloid cavity crepitation can be heard and felt on movement of the quarter or limb. Deformity is most marked in fractures of the ilium. In fractures of its external angle the fragment is drawn forwards and downwards by its muscular attach ments. When viewed from behind the angle of the haunch has disappeared, and a flatness can be observed on that side of the quarter. When the shaft is fractured there appears a falling down of the quarter, and some move ment and crepitus can be felt between the broken parts when the animal is moved slowly. Fracture of the shaft of the ischium is associated with a flatness of the buttock. A similar flat ness is to be observed in the rounded part of the quarter when the ischial tuberosity is broken. Fractures of the pubis or of the cotyloid cavity are not, as a rule, followed by deformity of the quarter. Fractures of the floor of the pelvis may occur without immediate displacement, so adding to the difficulty of diagnosis. In some of these cases oedematous swellings may appear in the region of the udder, scrotum, anus, or vagina, and may assist in forming a diagnosis.
Compound fractures of the external angle of the ilium occasionally occur. These, when neglected, are followed by suppuration and burrowing of the pus between the muscular planes and fascia. In fractures of the shaft of the ilium fragments may injure the iliac vessels, generally the veins, and the animal dies unexpectedly from internal haemorrhage. The same accident may occur in fracture through the obturator foramen with injury to the obturator vessels. Prognosis in fractures of the iliac angles is favourable. In fractures of the shaft, it will depend on the site of fracture and the amount of displacement. Even in young animals prognosis is bad if the fracture is near the joint with marked displacement. Fractures of the tuberosity of the ischium generally unite with deformity of the quarter; fractures through the shaft are much less favour able. When the body of the pubis is fractured without displacement, union may occur, taking place slowly. It is often imperfect with con tinued lameness. Fractures through the pelvic symphysis are hopeless. One through the acetabulum is the worst of all pelvic fractures.
In fractures of the angles of the ilium it is sufficient to rest the animal until lameness from the contusion wears off. This applies also to fractures of the tuberosity of the ischium. Other fractures of the pelvis, if treatment be attempted, must have complete rest continued for many weeks.
Fractures of the Scapula.Fractures of the scapula are not common. They most frequently occur through the spine or the neck, the result of external violence. They rarely occur through the body of the bone.
When the fracture is confined to the body of the scapula diagnosis is difficult, as there is little or no displacement, and crepitation is absent. When the fracture occurs through the neck, in addition to severe lameness, crepita tion with increased mobility will be detected on manual examination of the injured part. In fracture of the spine, movable fragments can be detected beneath the swelling. Fractures in this situation are frequently comminuted and open.
A fracture of the body or neck of the scapula can be treated only by rest. No bandage can be adjusted to keep the fragments in position. In a compound fracture of the spine the detached pieces of bone should be removed and an attempt made to render and keep the wound aseptic. Suppuration in this region often extends beneath the fascia.
Fractures of the Humerus.Fractures of the humerus are found in all animals as the result of external violence, and occasionally, in the horse, of muscular action. The fracture may
be through the shaft or through the condyles. As a rule, diagnosis in the former case is easy. Lameness is intense, with extreme flexion of the leg, so that the front of the hoof is in contact with the ground. There is well-marked local swelling, pain, and crepitus on manipulation, with increased mobility of the part. In dogs the fracture often occurs through the condyles, when diagnosis is more difficult. A fracture of the humerus is a grave accident in all animals. In the larger ones treatment offers little prospect of success. If the fracture be transverse with out much displacement and the subject young, there is some hope that the animal may be restored to soundness without much deformity of the limb. Such cases are occasionally seen in young cattle and horses. On the other hand, should the fracture be comminuted, impacted, or an oblique fracture with great displacement, healing will terminate with shortening and deformity of the limb, an excessive callus, and permanent lameness.
In a case of fracture of the humerus in a young horse or ox, absolute rest of the injured limb is the only method of treatment, as it is impossible to retain the parts in apposition by any appliances. In certain cases in the horse the animal could be placed in slings with advan tage. Young cattle could not be slung, but good recoveries take place in these animals if they are placed in a suitable shed, and kept on short litter, so as not to embarrass the injured limb. In the dog, especially when the is through the lower part of the shaft or condyle, something may be done in the form of retaining bandages to assist union and prevent excessive callus. The materials used should be as light as possible, and should extend from the meta carpus to the highest point attainable above the fracture. If the bandage can be kept in position, it may be removed after a month and the dog allowed exercise.
Fractures of the Ulna. Fractures of the ulna are generally found in the horse—the result of kicks and falls. The olecranon is broken across, generally into the joint, but occasionally the fracture is confined to the point of this process, and the elbow-joint is not implicated. These fractures are generally difficult of correct dia gnosis. There is intense lameness, with extreme flexion of the limb, and local swelling, but crepitation is usually absent as the fragments are drawn asunder by the extensor muscles of the forearm. Hence the difficulty in deciding whether the case is one of fracture of the. ole cranon, or a severe sprain, or a contusion of the caput muscles.
Muscular action with extreme flexion of the limb renders it impossible to bring together the fragments and retain them in apposition until union is complete. I have never seen a recovery in these cases in the horse. Animals with such fractures were, after many weeks in slings, un able to support weight on the injured limb or to extend it. In the dog, the shaft of the bone is sometimes fractured without implication of the radius. The prognosis in such cases is a little more hopeful. Using the radius as a splint, the limb should be immobilized by a suitable bandage.
Fractures of the Radius. Fractures of the radius in horses and in cattle occur, as a rule, without fracture of the ulna, but in dogs the violence breaks both bones. In horses, fracture of this bone is generally due to a kick, and may be compound owing to the superficial position of the part. In dogs, the accident is frequently the result of being run over, when the ulna is fractured at the same time.
Diagnosis offers no difficulty except in the case of the dog, when the radius only is frac tured—a rare condition.
Fractures of the radius in an aged horse or ox may be considered as incurable. In dogs, foals, and calves, the prognosis is more favour able, especially if the fracture is not near the carpus. Treatment consists in effecting reduc tion, and maintaining the fragments in apposi tion by appropriate bandages. In horses and cattle there is considerable difficulty in prevent ing these from slipping down. A plain bandage applied to the lower part of the radius before the application of the retaining ones prevents this to some extent. Retention bandages of an adhesive character will be found most suitable They should extend from knee to elbow-joint. A young horse should be placed in slings if possible. The movements of an ox should be limited by a suitable box or shed. In the dog the retention bandage should include both the elbow and the knee joints. Successful union in young horses is always associated with an excess ive callus and some deformity of the limb, but such animals have been known to make satis factory workers for many years.
Fracture of the Carpus. Fracture of the bones of the carpus is rare in the horse except in the case of severe broken knee. Fracture of the trapezium has been recorded. In both cases correct diagnosis is difficult and prognosis un favourable.
Fracture of the Metacarpus. Fracture of the metacarpal bones is seen most frequently in horses and dogs as the result of kicks and blows. Occasionally it occurs in the horse from no apparent cause when the animal is galloped or cantered on soft ground. In the horse the three metacarpal bones are fractured simul taneously, but in the dog the accident may be confined to one bone. It is, however, more common to find several broken as the result of a violent contusion. In such cases the frac ture is frequently an open one, or becomes so later from sloughing of the bruised tissues. The diagnosis of a fracture of the cannon bone in a horse is easy. It is more difficult in the case of a dog when one metacarpal bone only is fractured.
Treatment of a simple fracture of the meta carpals in a horse or ox is generally successful, especially if the division is midway in the bone. After reduction, a plaster bandage from the fetlock to the knee joint will be found most effective for retaining the fragments in apposi tion. After an interval of about six weeks this may be removed. As a rule, no deformity of the leg is observable. It is usually not necessary to place year-old horses in slings during treat ment. Older horses may require to be slung. In dogs a plaster bandage is equally effective for retaining the fragments in apposition and limiting movement of the parts. If the fracture is an open one it should be treated"secundum artem."The first essential is removal of all fragments of bone.
Fracture of the Sesamoid. Fractures of the sesamoid are recorded in the horse whilst gallop ing. The symptoms are intense lameness, local swelling, pain, and sinking of the fetlock towards the ground. If seen early a crepitation may be detected on movement, and depression felt between the fragments. Correct diagnosis is very difficult, differentiation from injury of the branches of the suspensory ligament being well-nigh impossible. Prognosis is unfavour able, as the means of retaining the fractured parts in apposition and at rest until union is completed are beyond our resources.
The diagnosis of fractured pastern is at times difficult. Severe lameness, suddenly manifested while the animal was in a trot or gallop with subsequent pain and swelling in the region of the pastern, would amount to almost conclusive evidence. In some cases of split pastern there is no displacement, so that crepitus and deformity are absent. In an oblique fracture, or in a com minuted one, both crepitation and increased mobility may be detected. The lameness and swelling at the pastern increase, the latter being of a painful and unyielding character. Fracture of the os corona or small pastern bone is brought about by the same causes as those operating in fracture of the os suffraginis, but this bone being partly within the hoof the fracture is more difficult of diagnosis.
Fracture of the navicular bone is commonly associated with navicular disease, especially after neurectomy. It also results from a gathered nail. Fractures of the pedal and navicular bones would be exceedingly difficult of diagnosis unless the fracture were open, and following penetration of a foreign body.
Prognosis in Fractures of the Pastern. Pro vided the articular surfaces are not implicated, prognosis is favourable in the case of fracture of the large pastern, although a considerable exostosis may remain. This is voluminous when succeeding a comminuted fracture, and the lameness remains chronic. Complete re covery is rare in fractures of the os corona. The succeeding exostosis, partly within the hoof, is always excessive and lameness remains. In fractures of the pedal bone from picked-up nails, or nails in shoeing, the issue is always grave if the fragments are not discovered and removed early. In fracture of the navicular bone no recovery can be expected.
Treatment of fractures of the pastern bones consists in a long period of absolute rest. A plaster bandage may be applied, extending from the coronet to above the fetlock joint.
The hollow of the heel must first be well padded, so that pressure may be evenly distributed on the injured and adjoining parts. Slings may be dispensed with. The animal should be encouraged to lie down frequently on a bed of sawdust or similar short material. Straw embarrasses the leg and frequently gives rise to bedsores. When the fracture is through the os coronae, a retaining bandage is of no assist ance. Prolonged rest is all that is necessary to assist union of the broken parts.
Diagnosis of fracture of the femur through the shaft offers no difficulty. The symptoms in the horse are extreme lameness, shortening of the limb, marked local swelling, intense pain on movement of the part, and increased mobility. If the animal is down it will probably be unable to rise without assistance, and then only when turned on the sound side. Crepitation may be absent or not well marked. If there is much displacement of the fragments it may be entirely absent. In cases of a fracture through the neck some difficulty may be ex perienced in arriving at a conclusion as to whether fracture exists or not. The history of the case, and the increasing local swelling with marked shortening of the limb, assist in arriv ing at a diagnosis. Fractures through the trochanters and condyles are also difficult of correct diagnosis, though they may be guessed at. The only symptoms are lameness, local pain, and swelling. The contraction of the attached muscles draws the fragments apart, so that crepitus is absent. Fractures of the femur are of grave import in all animals, more particularly in the horse and ox. In these animals repair is incomplete, leaving shortening of the limb, excessive callus, and permanent lameness. Recorded cases of complete union of fracture of the femur in the horse with sound ness and full capacity for work should be received with caution. Such statements are frequently based on wrong diagnosis.
In small animals, including dogs, the pro gnosis is more hopeful, but much depends on the amount of displacement of the fractured parts. If slight, the succeeding shortening of the limb and the ensheathing callus will be less marked, and the animal may in time walk practically sound. On the other hand, if the amount of displacement be great, the succeeding callus will be excessive. Also, masses of muscle may be interposed between the fragments, and the formation of the callus prevented. In such instances, marked deformity of the limb and lameness will remain. If it be decided to treat a case of fracture of the femur in a horse or ox, complete rest is the only course to be adopted. Any attempts to reduce the fracture are to be deprecated, as it is impossible to overcome, or successfully oppose, the great resistance of the muscles of the quarter and thigh. Even in small animals attempts at reduction of the fracture frequently fail and do great harm. If successful, it is most difficult to maintain by any method of bandaging or appliance, owing to the powerful muscular contraction, and the subsequent movements of the animal. It is therefore, under such circumstances, better to aim at keeping the fractured parts in apposition, without reduction, and at rest, with an appro priate retention bandage applied from the point of the hock to a point as high up the thigh as possible. The difficulty is to prevent such a bandage slipping down. This can to some extent be prevented by using one made of some adhesive material, carrying it over the quarter, and taking it round the opposite leg. In many instances these bandages have small effect on the union of the fracture, and add only to the discomfort of the animal, especially if the injury be towards the upper part of the femur. Then it is better to treat the case on expectant lines without bandages.
Fracture of the Tibia.Fractures of the tibia are seen in all animals, and are common in the horse. They are due to external violence— direct, in the form of kicks to the inner surface of the limb; indirect, from slipping on ice and smooth pavements, and in going at a fast pace over uneven ground. The fracture may be simple, compound, or complicated, with or without displacement. In the horse the fracture is frequently a compound one. The wound communicating with the fracture may have been inflicted synchronously, or the frag ments may, by subsequent movement, have been forced through the soft structures. Frac ture without displacement is peculiar to and not infrequent in the horse. In this case the bone may at first only be fissured. Fracture is completed and displacement brought about later by the act of rising or lying down, or by movements performed by the animal during ordinary work. On the other hand, fracture may have been complete from the outset, the strong periosteum and fascia peculiar to this part preventing any displacement for a time. When the resisting character of these tissues is weakened by the subsequent inflammatory process, separation of the fragments follows. In many recorded cases the associated lameness was either absent, or was so slight that the injured animal was at work some days after the injury, before displacement occurred. No definite time-limit can be given when, after such injury, displacement may occur. Not many days is the rule, but instances have been given in which displacement has been delayed some weeks.
Fractures of the tibia with displacement present no difficulty in diagnosis. Extreme lameness, the pendulous limb, the evidence of pain and crepitation on manual examination of the injured part are so pronounced that error is impossible. But in cases without displace ment considerable difficulty will be experienced in deciding whether fracture exists or not. Lameness, and pain on pressing the injured part, are the only symptoms present. The local swelling is often negligible, owing to the resist ing character of the subcutaneous tissue cover ing the inner surface of the tibia. In such cases it is best to express no immediate opinion as to existence or non-existence of fracture. In the horse, fracture of the tibia with displacement is hopeless. When displacement has not occurred there may be some slight chance of recovery if the fracture be partial, or the fissure of small extent. The horse must be given absolute rest, as soon as lameness is discerned and localized in the tibia. Every case of lameness in the tibia of the horse should be treated as a fracture. The animal must be placed in slings or tied up short for three weeks. No effective support can be obtained from retaining bandages applied to the leg, owing to the impossibility of obtaining uniform pressure over and about the injured part, and of preventing the bandages from slipping down. It would appear that in certain cases where the tibia is fissured, there is no attempt at repair. A five-year-old cart mare, found dead lame from no apparent cause, evinced pain on pressure of the inner and upper part of the tibia. The animal was kept at rest in slings for two months without benefit. On post-mortem, a fissure was discovered six inches in length and three-quarters of an inch deep, extending into the joint in the fossa of the internal meniscus. There was considerable thickening of the adjacent periosteum, but no evidence of repair of the fracture could be detected. Sometimes after an animal has been treated on the above lines for suspected fracture of the tibia, an exostosis may be discovered on the inner surface of the leg. This cannot be treated as conclusive evidence of previous fracture, as in severe contusions of the peri osteum the exudate frequently becomes ossified.
In foals a simple fracture with displacement may be treated with a fair amount of success, especially if the injury be towards the inferior part of the shaft. Treatment consists of a pitch retention bandage and limited exercise. There is always a certain amount of deformity in the limb afterwards. In cattle and dogs, frac tures of the tibia generally unite in the course of a month. Retention bandages are generally applied to the injured leg. Their utility is questionable, as complete and satisfactory union of the fracture takes place in both animals without their aid, if the patient be confined to a limited space.
The treatment of compound fractures of the tibia is hopeless in any animal except the dog. Even in this animal, when the fracture has been seen early, and before serious wound contamination has occurred, prognosis should be guarded.
Fractures of the Bones of the Hock.Fractures are rare and may be looked upon as incurable in horses and cattle. In a fracture of the os calcis there would be extreme lameness, flexion of the joint, and local swelling, with a flaccid condition of the tendo AchiLlis. Fracture of the astragalus, or of any bone of the hock, would be difficult to detect without a com municating wound, and any opinion as to its existence would be conjectural except in the case of compound fracture.
Fracture of the Metatarsus.What has already been said respecting fractures of the metacarpal bones and the anterior digits applies to corre sponding bones of the hind limb, with the reser vation, that fractures are of more serious import in the hind limbs than in the fore ones.