Abstract
An adult female jaguar (Panthera onca) (45 kg) was assessed for multiple severe puncture wounds to the right forelimb inflicted by a conspecific during an introduction. The pair was initially introduced with minimal aggression 1 week prior to presentation. During this period, the animals were separated in the evening, with visual and tactile contact through chain link fence. The evening before presentation, the male was able to grab the female’s right front foot underneath this shift door, producing the initial injury.
The following morning, due to severity of the wounds, the jaguar was immobilized with medetomidine 40 µg/kg (Dormitor, Pfizer, Exton, PA 19341, USA) and ketamine 4.4 mg/kg (Ketaset, Fort Dodge Animal Health, Fort Dodge, IA 50501, USA) IM by dart via a CO2 injection pistol (Dan-inject-Wildlife Pharmaceuticals, Fort Collins, CO 80524, USA). The jaguar was then maintained using isoflurane (Isoflo, Abbott, Chicago, IL 60064, USA). Physical examination confirmed multiple severe puncture wounds and crushing injury to the distal right front limb at the metacarpus and traumatic dermatitis to both forelimbs. One of the punctures of the right front limb entered dorsally and exited at the palmar aspect of paw. Several lacerations on the right carpal and metacarpal pads were present, including one which exposed the proximal phalanx of digit 1. Radiographs of the distal right forelimb revealed no orthopedic abnormalities. The wounds were surgically debrided, the first digit was amputated at the metacarpophalangeal joint, and primary closure with 2.0 polyglyconate (Maxon, Tyco Healthcare, Norwalk, CT 06856, USA) in a cruciate pattern was made to reduce exposure of the extensor tendons over the distal metacarpophalangeal joint. The milder injuries to the left forelimb were thoroughly irrigated with dilute chlorhexidene solution. The jaguar was treated with penicillin 60,000 IU/kg SC (Han-Pen B-Hanford Pharmaceuticals, Syracuse, NY 13201, USA) and enrofloxacin 2.5 mg/kg IM (Baytril, Shawnee Mission, KS 66216, USA). The animal was reversed with atipemazole 5 mg IM (Antisedan, Pfizer) and recovered uneventfully. Meloxicam, 0.1 mg/kg, PO SID (Mobic, Abbott) was administered the next day as well as marbofloxacin 50 mg, PO, BID (Zeniquin, Pfizer) post-procedurally. With the extent of skin injury to the right forefoot, viability was questionable and sedation for reassessment was scheduled in 3 days.
The jaguar was immobilized as before to assess the wound. The right distal limb at the mid-metacarpus had involved soft tissue that was cold, gray, and the digital nail beds associated with this limb were purple. The wounds were thoroughly cleaned, and a spoon splint was placed to stabilize the limb against further injury. The same day, the animal was immobilized a second time as previously described for transfer to Oklahoma State University, College of Veterinary Medicine (Stillwater, OK) for limb sparing surgery. Pre-operatively, the distal right forelimb was ultrasounded to assess blood flow on the dorsal and palmar aspect of the limb at the metacarpus. No visible vasculature was identified ultrasonographically. Due to clinical presentation, a mid-metacarpal amputation was performed in an attempt to salvage the remainder of the right front limb. The metacarpal pad had dubious viability but was left in place as a weight-bearing surface upon recovery. A wet-to-dry dressing was placed and covered with a modified Robert Jones bandage on the right forelimb. Bacteriologic culture and sensitivity of the excised tissue revealed Staphylococcus, Streptococcus, Enterococcus, and Micrococcus spp. susceptible to most antibiotics. At that point, amoxicillin/clavulanate 25 mg/kg BID, PO (Clavamox, Pfizer) was initiated in addition to the prior regimen.
The morning following surgery, the animal had removed the distal aspect of the bandage, exposing the avulsed metacarpal pad. The animal required another sedation by the prior route for cast placement. However, the cast was removed that same day by the jaguar. A second attempt to securely bandage the affected area was made to provide as much limb as possible for future reconstructive efforts. A modified 5-gallon bucket and leather collar were fashioned into an Elizabethan-collar to prevent access to the bandaged limb. However, by the next morning, the cast had slipped, the surgical wound was exposed, and the first collar was cracked. Further sedation was needed to lavage the wound, apply a lighter wet-to-dry bandage and to replace the Elizabethan-collar. Elastikon (Johnson and Johnson, Summerville, NJ 08876, USA) stirrups were applied with ether spray (Pyroil, Valvoline, Lexington, KY 40509, USA) to further secure the bandage by creating an “ether-patch” to the skin. The bandage remained in place for 3 days. Twice weekly bandage changes were instituted to surgically debride the wound and replace the wet-to-dry bandaging. Propofol 40–60 mg IV (Propoflo, Abbott) was added to the protocol in several of the immobilizations to improve sedation plane during the bandage changes. At each recheck examination, the amputation site was viable and granulation tissue quickly developed but moderate amounts of purulent material persisted on granulation bed. During these biweekly immobilizations, several bandages techniques were attempted to provide support for the amputation site without compromise to the adjacent healthy skin. Following, one re-bandaging procedure, a small amount of brown exudate was observed in the jaguar’s pharynx upon extubation. With the frequency of procedures, stress-induced gastritis and ulceration was a concern and managed preventively with omeprazole, 1 mg/kg PO, SID (Prilosec, AstraZeneca, Merck, Whitehouse Station, NJ 08889, USA) and sucralfate, 1 g, PO, TID (Carafate, Warrick Pharmaceuticals, Reno, NV 89506, USA).
Five weeks after the initial injury, the granulation bed was appropriate to attempt reconstructive surgery to provide a more appropriate weight-bearing surface of pad at the amputation site. Autografts of pad from the right metatarsal pad, all four right rear digital pads, left metacarpal pad, and two of the left digital pads were sutured with simple interrupted absorbable sutures in a rosette pattern on the distal end of the amputation site.
Bandage changes were reduced to once weekly under sedation and included a shoulder strap to secure the bandage to the right front leg. The feet (left front and right rear) that provided tissue for the reconstructive procedure were lightly bandaged with nonadherent bandage material to cushion weight bearing and prevent severe contamination. A week prior to the autograft, the jaguar was started on acepromazine, 2 mg/kg PO, BID (ProAce, Fort Dodge Animal Health) in an attempt to decrease the anxiety of the immobilizations and bandages. The jaguar appeared less anxious between immobilization periods with initiation of the acepromazine.
To the authors’ knowledge, no reports of mid-metacarpal amputation and pad reconstruction in large cats have been documented. This technique may prove to be effective as an alternative to whole leg amputation for severe traumatic distal limb wounds in large felids.
Acknowledgments
We thank Dr. John P. Hoover for his expertise and Dr. Martha Larry and the large carnivore staff at the Tulsa Zoo for their assistance.