In ankylosing spondylosis, exostoses develop on the ligament of the ventral aspect of the lumbar vertebrae, primarily in older bulls. Fracture of the exostosis and associated vertebrae causes pressure on the spinal cord, which results in severe ataxia or paralysis. There is no treatment.
This nonspecific condition affecting mainly the hip and stifle is characterized by degeneration of articular cartilage and eburnation of subchondral bone, joint effusion, and fibrosis with calcification of the joint capsule.
Many causes and predisposing factors influence the development of degenerative joint lesions. There is almost certainly an inherited predisposition to degenerative arthropathy. Certain conformations, eg, straight hocks in beef bulls, are also incriminated. Joint instability after trauma is a common cause. Nutritional factors involved in some cases are rations high in phosphorus and low in calcium, which probably influence the strength of subchondral bone. Copper deficiency or fluoride poisoning also may act similarly. Forced traction of a calf in breech presentation can impede the blood supply to the hip joint, and arthritis may result. The role of infection is unclear. Infectious arthritis in calves usually produces severe changes in the hock, but degenerative arthropathy rarely involves this joint.
Bulls fed high-grain diets for show may become lame when as young as 6–12 mo, but most cases are first noticed at 1–2 yr.
Onset is gradual (later in bulls), and both hip joints are usually affected; stifle involvement is rare. Lameness to the point of incapacitation, with crepitation of degenerate joints, may develop in a few months; however, correlation between pathologic changes and clinical signs is poor. The earliest changes occur in the acetabulum and on the dorsomedial surface of the femoral head.
In the stifle, the medial condyle of the femur shows the earliest changes. Because degenerative arthropathy may result from any of several initiating factors, a specific diagnosis may be difficult. Radiographic, cytologic, and microbiologic evaluation of the synovial fluid are useful diagnostic aids. Arthroscopy of articular surfaces and ligaments may help attain a definitive diagnosis and prognosis.
Changes in the joints are usually irreversible by the time of diagnosis. Palliative treatment in valuable breeding animals should be undertaken with the knowledge that the condition or predisposing factors may be inherited. The diet should be carefully analyzed and, if necessary, corrected. This is especially important in fast-growing animals, in which adequate exercise is indicated and overfinishing should be avoided.
Luxation of the coxofemoral joint is usually upward. It is seen in bulls serving cows confined on a slippery surface and in cows riding each other. The affected limb appears shorter than the contralateral limb. The hock is turned inward and, when trying to walk, the animal appears to be dragging one foot behind the other.
Resolution is possible, provided that the head of the femur or the rim of the acetabulum has not been fractured. The animal should be deeply sedated to the level of recumbency. A rope should be looped around the groin of the affected limb, which should be uppermost. The free ends of the rope should be tied around a tree or some other fixed object, and traction should be applied to forcibly extend the limb. Downward pressure should be applied to the hock, which should be strongly rotated outward (upward) until the head of the femur slips back into the acetabulum. Traction should be applied at several angles until the head of the femur clicks back into the acetabulum. If the head of the femur or the rim of the acetabulum is fractured, there will be considerable crepitation and the limb will displace as soon as traction is stopped.
Intermittent fixation of the patella on the upper part of the femoral trochlea results in a characteristic jerky action of one or both hindlimbs. The limb remains in caudal extension for a longer period than normal and may even be dragged for a few steps before clicking forward to a normal posture. In young animals, the condition may resolve spontaneously. For luxations that do not resolve, medial patellar desmotomy should be performed.
Dislocation of the Fetlock
This is seen frequently in young cattle when they cross cattle guards (grillwork laid over a pit as a gate substitute). Tranquilization or light anesthesia facilitates replacement of dislocated structures. A padded fiberglass cast maintained in place for 3 wk usually promotes a satisfactory recovery.
This bilateral malformation of the hip joint is often associated with secondary osteoarthritis. It may be present at birth. However, abnormal gait may develop in rapidly growing animals. Usually, it is possible to rock the hindquarter to produce a click as the head of the femur pops in or out. Radiography may confirm the diagnosis in young animals. There is no treatment.
Bone fractures occur in cattle of all ages, but they are most common in those <1 yr old. Corrective procedures may be justified economically in this age group, provided that joints are not involved. External fixation techniques or Thomas splints have been used successfully. In selected cases, percutaneous transfixation or internal fixation may be attempted.
Fractures of major long bones in adult cattle usually are not treated. The tuber coxae may fracture when cattle are hurried through narrow doorways. In these cases, spicules of bone may penetrate the skin, or unsightly distortions of the flank can result. Fractures of the proximal and intermediate phalanges may be considered for treatment in tractable, young adult cattle.
Fracture of the distal phalanx is relatively common in adult cattle. Onset of lameness is rapid, and the pain is usually severe. If the medial digit is involved, the animal may seek relief from the pain by crossing its legs. Natural recovery is prolonged, and because most such fractures extend into the distal interphalangeal joint, a debilitating arthritis may develop at the fracture site. If treatment is undertaken, the sound digit should be elevated on a wooden block, and the affected digit immobilized in a flexed position to the block using methyl methacrylate adhesive.
Septic Arthritis of the Distal Interphalangeal Joint
Infection enters the distal interphalangeal joint via 3 possible main sites: 1) the dorsal commissure of the interdigital space, via penetrating trauma or complicated footrot (interdigital phlegmon); 2) sandcracks; or 3) white line disease or retroarticular abscess.
Most frequently, one of the causal lesions is present and the transition from the initial lesion to the joint infection is readily apparent. However, when a swollen foot is treated before the cause has been established, a joint infection may have been ongoing for weeks before the true nature of the condition is diagnosed. If aggressive treatment of a footrot case does not lead toward resolution within 3 days, septic arthritis should be suspected. Increased pain, together with swelling of the anterior region of the coronary band in cases of sandcrack and white line disease, is suggestive of joint infection. Using regional analgesia and strict aseptic technique, an aspirate of the joint can be collected and examined for infection. A radiograph may indicate an abnormal separation of the joint surfaces.
Digital amputation is indicated in animals that have a limited life expectancy, eg, old or poor-producing animals. The procedure is simple, quick, can be performed in standing animals under regional analgesia, and in most cases, produces rapid relief. Amputation is performed through the skin with an embryotomy wire placed as close to the skin-horn junction as possible. Hemorrhage is arrested by means of a tight bandage.
Arthrodesis fuses the distal and middle phalanges and is used to extend the functional life of valuable animals. General anesthesia is recommended. A 1-cm canal is drilled through the abaxial wall into the joint, and a second canal is drilled from the causal lesion into the joint. The joint cavity is enlarged by curettage, and a drainage tube drawn through. Continuous irrigation with sterile saline should be performed for 2–3 days. A wooden block is then applied to the sound claw, and the affected digit immobilized by fixing it to the block with methyl methacrylate. Immobilization is further facilitated by encasing the digital region in a cast. The cast is removed after 4 wk.
(Bog spavin, Puffy hock)
Serous tarsitis is characterized by 3 soft, fluctuating swellings between the ligaments of the femorotarsal joint. In some instances, this condition is heritable. It does not cause pain or lameness. In later life, there may be a predisposition to arthritis. The condition is diagnosed by depressing the swelling of the joint capsule at one location and palpating the fluctuation that is seen at another. There is no successful treatment.
Last full review/revision March 2012 by Paul R. Greenough, FRCVS