A 2-yr-old female forest buffalo presented with acute trauma to the right horn following a fight with a conspecific. The trauma was significant, resulting in the complete avulsion of the horn base and associated frontal bone, exposing the frontal sinus.
The animal was immobilized with 3.3 mg of carfentanil (Zoo Pharm, Laramie, WY, USA) mixed with 100 mg of xylazine (Lloyd, Shenandoah, IA, USA) in a single dart. Supplemental restraint was achieved with 500 mg of ketamine (Vedco, St. Joseph, MO, USA) i.v., as a bolus. At the conclusion of the examination and treatment episode, chemical restraint was successfully antagonized with 5 mg atipamezole (Pfizer Animal Health, Pittsburgh, PA, USA) i.v., 95 mg atipamezole i.m., and 300 mg naltrexone (INNOVRx Pharmacy, Yorba Linda, CA, USA) i.v.
Examination of the affected area of the skull revealed complete avulsion of the horn, cornual process, juxtaposed skin, and frontal bone as a unit, leaving an 8 cm opening into the frontal sinus. The area was debrided and lavaged to remove visible debris and contagion. A methacrylate (Nasco West, Modesto, CA, USA) patch with enrofloxacin (Bayer Corp., Atlanta, GA, USA) and ampicillin (American Pharmaceutical Partner, Schaumburg, IL, USA) was formed to cover the defect. A small amount of this liquid was painted just inside the frontal sinus to create a purchase on the frontal bone to help hold the patch in place. A gauze sponge saturated with the methacrylate/antibiotic mixture and was then laid over the bony defect, covering the opening into the frontal sinus. The remaining liquid was then poured over the gauze patch creating a solid patch over the entire defect, extending out over the affected skin by approximately 2 cm circumferentially. Systemic antibiotic therapy was initiated with procaine penicillin G (Agrilabs, St. Joseph, MO, USA) at the point of triage, followed by enrofloxacin by dart for a total of 7 days.
Eleven days later the animal was sedated because the initial methacrylate patch had partially fallen off. The residual methacrylate from the original cap was removed, along with a mucinous discharge, the remnants of the gauze patch, and redundant regenerative sinus mucosa. At this time the frontal sinus was partly closed. The area was debrided and another methacrylate cap was placed over a central layer of hydrophilic wound dressing that covered the healing frontal sinus fistula.
The methacrylate cap remained in place for another 68 days when it spontaneously fell off. The result was a firm, well-epithelialized healed scar covering the entire defect. The resulting healed scar was monitored visually every few days for an additional 3 wk and at that point the animal was discharged from medical surveillance for this problem. Six years later the animal has regenerated a new horn which somewhat resembles the original horn. Management of this kind of injury has been reviewed for domestic cattle, and requires aggressive triage followed by regular wound care measures.1 Managing this kind of severe trauma in wild artiodactylids using these same techniques can be very difficult. The authors feel the aggressive initial triage, along with the benefits of methacrylate wound coverings as an alternative to intense daily wound management provided an optimal approach for management of this severe, possibly life-threatening injury.
1. Ward JL, WC Rebhun. 1992. Chronic frontal sinusitis in dairy cattle: 12 cases (1978–1989). J. Amer. Vet. Med. Assoc. 201: 326–329.