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Carpal Hygroma
Carpal hygroma is a localized swelling of tissues, including the precarpal bursa, dorsal to the carpal joint. It results from intermittent mild trauma to the precarpal area caused by lack of bedding or a poorly designed manger. Brucella abortus may be isolated from the false bursa of some cases in countries where this organism has not been controlled. The lesion is a firm swelling, possibly fluctuating and up to several inches in diameter, located over the dorsal aspect of the carpus. The hygroma is a lesion that is very difficult to resolve. The first step is to ascertain radiographically if there is more than one cavity. Each cavity should be drained and infiltrated with a long-acting corticosteroid preparation. Surgical removal is messy, with little guarantee of a successful outcome. Introducing irritant materials into the cavity has had uncertain results. If the animal is milking and eating well, hygromas should be left untreated.
Frostbite
A calf born into an environment of ~0°F (–18°C) with a high wind chill factor is at risk of hypothermia. A weak calf, born to an exhausted cow after a long labor in a cold and windy environment (eg, a temperature of 20°F [–7°C] and a wind of 30 mph [50 km/hr]) can suffer frostbite of the feet and other extremities. After several days, the calf becomes reluctant to follow its dam or to stand but has a normal appetite. A severely affected calf has a crusted muzzle, devitalized ear tips and tail end, and cold hindfeet. (The forefeet are generally placed under the body when the calf lies down and, therefore, are protected from the cold by body heat.) Several days to weeks later, the devitalized tissue (including the hooves) begins to slough, and the calf refuses to stand.
The major diagnostic problem is differentiation from fescue or ergot toxicity. Age of the animal and temperature and wind chill on the day of birth help to verify the diagnosis. Treatment is often unsuccessful.
Hematoma
A hematoma is a collection of blood, frequently clotted, beneath the skin or in a deep muscle mass (most frequently of the thigh). Hematomas are caused by trauma, most frequently from one animal butting another in confined quarters or from 2 animals attempting to rush through a narrow doorway at the same time.
In some locations, a hematoma can be confused with an abdominal hernia or a large abscess. Aspiration of fluid using a strict aseptic technique should precede any attempts to open a swelling. Hematomas should not be opened because the hemorrhaging vessel is almost impossible to locate and will continue to bleed until pressure within the hematoma equals that in the vessel. Bleeding from beneath a clot rarely stops spontaneously until either the blood pressure falls or the clot begins to organize. Eventually, this process occurs, and most of the clot will be resorbed. However, it is quite usual for an unsightly irregular lump to remain.
Rupture of the Gastrocnemius Muscle or Tendon
Rupture of the gastrocnemius muscle is relatively rare. It is most likely to be associated with deficiencies of calcium, phosphorus, and vitamin D. Prolonged recumbency, with resulting myositis and struggling to rise, occasionally precipitates rupture of one or both of these muscles. Occasionally, the condition has been associated with pyelonephritis, which presumably caused a myositis, weakening the muscle enough to permit rupture. Injections of irritating medicaments into the gastrocnemius muscle may cause necrosis and rupture.
The hock remains flexed. When the muscle is completely ruptured, the standing animal rests the hock and distal portion of the limb on the ground or walking surface, which is diagnostic, although rupture of the Achilles tendon may produce an identical gait.
Successful treatment is extremely unlikely in heavy adult animals. A leg cast or splint that maintains the hock in extension, supplying adequate vitamins and minerals, and proper nursing may be successful, but a long recovery period is required.
Rupture of the Achilles tendon is usually traumatic. The clinical signs are similar to those of rupture of the muscle.
Rupture of the Peroneus Tertius Muscle
The peroneus tertius muscle can be forcibly avulsed from its insertion by accidents associated with mounting or, more frequently, by the inexperienced use of ropes to restrain a hindlimb.
The hock is abnormally extended, while the stifle remains flexed. The limb cannot be advanced normally, the calcanean tendon is flaccid, and the hooves may be dragged. The site of avulsion may be painful to the touch. A specific diagnostic feature is that the limb can be pulled backward without any resistance from the animal.
The condition may improve slowly if the animal is confined in a stall (loose) for several months.
Tarsal Cellulitis
Tarsal cellulitis is a false bursa characterized by a firm, subcutaneous swelling on the lateral aspect of the hock that has little effect on joint mobility. It is caused by severe abrasion of the skin and subcutaneous tissue overlying bony prominences. The skin may be excoriated by contact with concrete and particularly sharp curbs. Superficial abscesses must be drained extremely cautiously because there is considerable danger of entering the joint. Padding and bandages should always be applied. Poultices rapidly reduce acute swelling.
Last full review/revision March 2012 by Paul R. Greenough, FRCVS
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