A 14-month-old male whooping crane (Grus americana) presented for acute onset, non-weight-bearing lameness of the right leg, holding the limb caudally directed. No fractures or luxations were identified, although the stifle had reduced range of motion on extension. After no response to a six-day course of non-steroidal anti-inflammatory drug therapy (meloxicam), an exploratory surgery on the stifle was performed by a veterinary surgeon. Muscle and tendon were found constricted around a distal segment of the fibula which had healed in an abnormal orientation from a previous fracture. This segment was excised, permitting stifle extension and normal orientation of the leg, but with knuckling-over of the foot.
The foot was splinted to encourage extension of the toes to facilitate weight-bearing. Unfortunately, splinting the digits in extension conflicted with the leg’s normal biomechanical movements (hock flexion coincident with flexion of the toes). To permit normal range-of-motion and maintain the foot with the toes extended, a flexible prosthetic “boot” was fabricated from fiberglass mesh and silicone. This prosthesis enveloped digit 3 extending proximally to the distal tarso-metatarsus. It permitted normal flexion of the toes as the hock flexed yet maintained that digit in extension to allow for weight-bearing. The bird adjusted to the “boot” well and demonstrated near normal gait shortly after application. The device was removed after 12 weeks and normal use of the limb has maintained to date.
This novel prosthesis allowed near normal function of the foot. It can serve as both a support during convalescence after injury or as a permanent “prosthesis” should function not return.
The authors wish to thank Dr. Tom McNicholas for his surgical expertise, Mike Lincoln for his fabricating skills on the “boot” and the Bird Division staff for their daily care and monitoring of the crane during its treatment and recovery.