18 Oct 2023
Thistle was given the prosthetic hoof, designed and fitted by teams at the RVC, after being born with fractured digits.
Paul Imrie
Job Title
A Nubian goat called Thistle is adapting to life with a 3D-printed prosthetic foot resembling a ski boot after having suffered from a severely fractured limb as a kid.
The goat was five weeks of age when she was first referred to the RVC Equine Referral Hospital after being born with a suspected deformity.
After diagnosis of fractured digits by her vet, she was sent for further evaluation and treatment at the RVC.
A CT scan revealed chronic, open, comminuted, displaced, non-articular, diaphyseal fractures of the phalanges, with complete loss of preservation and suggestions of septic arthritis and luxation.
Treatment options including euthanasia and amputation at either the level of the radius and amputation at the level of the distal metacarpi were discussed, the hope being a prosthesis could later be fitted to the distal limb.
After amputation at the level of the distal metacarpi was opted for, the procedure was carried out under general anaesthesia, with a postoperative CT performed to obtain exact measurements of the stump.
Richard Bomphrey, a professor with the RVC’s Structure and Motion Lab, worked with senior lecturer in equine soft tissue surgery Melanie Perrier and her team to design and make a 3D prosthetic foot.
The resulting prosthesis, fitted three weeks after the amputation, resembles a ski boot with Velcro-style straps and was 3D printed with polyactic acid filament, a natural thermoplastic polyester from renewable resources such as corn starch or sugar cane.
A threaded bolt was inserted at the bottom to allow for adjustments in height as Thistle grows.
Dr Perrier said: “Thistle’s progress and her initial response to the prosthesis are very encouraging. While she initially only used the prosthesis for a few steps, after a few days she was mostly weight-bearing on it and showing a more natural gait.
“As Thistle had been walking on three legs since birth, she presented with severe muscle atrophy over her right forelimb, and so this will need to be built up progressively. She will wear her prosthetic for a little longer each day and undergo regular physiotherapy exercises.
“She will only wear the prosthesis for a few hours daily to start with so she can get accustomed to it gently, and this will be increased over the following weeks and months so that, ultimately, she can wear her prosthesis throughout the day.”
