Management Plan Delayed union is commonplace in large animals. Due to the size and weight of the calf and the extent of the metacarpal fracture, primary bone healing is virtually non-existent. Rigid stabilization will probably not occur, and implants (internal fixation) will not withstand the forces placed upon them and risk further contamination. The metacarpal fracture in this calf is complicated by infection, and therefore has a less than favorable prognosis. The most ideal reduction technique for this calf would be a closed reduction. A closed reduction has minimal effects on local soft tissue structures, reducing the risk of further fracture contamination and compromise to the remaining blood supply. As this animal is young and likely has an appropriate number of osteoprogenitor cells, a closed reduction should allow for rapid healing of this fracture. There are several options for immobilization of fractures distal to the elbow. External fixation is the most favorable method due to the septic condition of the limb and possible compromise to the existing blood supply. A Schroeder-Thomas splint can be used in food animals to immobilize metacarpal fractures, providing some weight-bearing capabilities and only moderate stability. It is known, however, that cattle do not adjust well to this type of splinted bandage and it would not allow for local treatment and the opportunity for drainage of the septic fracture site. External fixation with pins seems highly favorable if the owner is willing to pay for the procedure. The metacarpal region is distal enough to allow the fixation devices to be set without impinging on other parts of the calfÕs body, and there is adequate room at the fracture site to allow placement of the proper number of pins (three above and three below the fracture). Specifically, a Type II external fixation device should be used Ð this involves centrally threaded pins stabilized with bilateral side-bars. Pins should be placed at regular intervals as far from each other as possible, but not any closer than one centimeter from the fracture line. Pins should be placed in a similar positional plane that minimizes injury to associated soft tissue structures (flexor, extensor tendons, radial nerve, etc.). Side bars used can be either metal (where pins are attached with clamps) or acrylics (PMM or Technovite_, which have the advantage of increased versatility for connecting the fixator pins. This type II external fixation will allow for easy access to the draining tracts, sloughing tissue, and granulating wounds for debridement and lavage. Internal fixation is often not applicable or practical for cattle. The procedure is quite expensive, and often the pins are not strong enough to withstand the excessive forces placed upon them. Due to the relationship of the long bones (metacarpal bones) to joint surfaces and their configuration, intramedullary pins are seldom used in cattle. Open surgery will risk the spread of wound contamination to the rest of the limb, and further damage local tissues and compromise blood supply. To battle the bacterial infection present in the epithelial tissue surrounding the metacarpal region and at the fracture site, systemic antibiotics should be used (damage to the blood supply in this region appears to be minimal). As the culture results indicated that the E. coli and Staph. aureus were susceptible to second and third generation cephalosporins, amoxicillin, and gentamycin, use of these antimicrobials would be indicated for 6 weeks post-fixation. A non-steroidal anti-inflammatory such as flunixin meglumine (Banamine) could be used to decrease inflammation, reduce pain, and improve blood flow. Post-operative management of an external fixation is significant. Pin tracts should be cleaned daily to maintain healthy peri-pin granulation tissue. As management of an externally fixated fracture is economically draining, euthanasia is an alternative consideration for this case. However, as this was an embryo transfer-calf, the value of this animal might be increased slightly and external fixation may be a viable option for the owner. As this is a front limb rather than a rear limb abnormality, there may not be significant compromise to the breeding ability of this bull calf.