Veterinary Orthopaedics

Partial 3D Jaw Replacement Procedure Carried Out on Companion Dog

Gary Bradshaw — Wed, 10 Jul 2019 09:18:17 GMT

Dr Ryk Botes - who runs a centre of excellence for orthopaedics based out of Medivet Faversham - has carried out a successful 3D printed partial jaw replacement on a companion Shih Tzu dog.

The surgery was performed by Dr Botes, a Medivet Branch Partner with a special interest in orthopaedics and replacement surgery. He was touched by the plight of eight-year old Shih Tzu, Poppet - a rescue dog whose lower jaw was broken on both sides. Dr Botes felt that the only way to properly fix the dog’s jaw was to attempt a partial jaw replacement.

Although the technique is used in humans, Poppet’s small size made it particularly difficult to design and produce a custom-made implant. Working with specialist firm 3D Metal Printing, Dr Botes was able to create a titanium jaw and perform the operation to fit to Poppet’s jaw. Poppet is now making a good recovery and is “a different dog”.

Poppet was adopted two years ago from a rescue centre by Daphne Harrigan from Pitsea in Essex. Apart from her broken jaw, Poppet had other health problems which suggested she may have been used for breeding on a puppy farm. Poppet filled a hole in Mrs Harrigan’s life, following the loss of her husband 11 years ago. Knowing how special Poppet is to Mrs Harrigan, Dr Botes took on the challenge to fix the lower jaw, which was broken on both sides with one side of the jaw missing a large segment of bone.

Based on CT scans sent by Dr Botes, 3D Metal Printing (based in the Innovation Centre at the University of Bath) created the implant, making a titanium jaw for Poppet. This was fitted by Dr Botes in a one-hour operation.

Since the operation Poppet has made a good recovery and is ‘a different dog’, according to Mrs Harrigan’s daughter Debbie Crouch. “Before the operation, her tongue lolled out of her mouth permanently and she couldn’t eat or clean herself properly. Now she can and it’s as if she has a whole new lease of life. It’s wonderful to see her – and equally wonderful to see how happy she makes my Mum.”

Ryk Botes worked until recently at Medivet Chafford Hundred, but now runs the excellence centre at Medivet Faversham, in Kent.

“Veterinary science is not just about performing surgery or about generating an income. In addition to the welfare of our patients, we also need to consider the welfare of their owners,” he said. “The experience gained in the design, production and fitting of the jaw replacement implant will benefit many patients in the future.”

Alberto Casanoto, Managing Director of 3D Printing, said: “The beauty of this technology is that you can create a highly precise, personalised implant very cost-effectively. The jaw we created based on the CT scans Ryk sent to us fitted Poppet perfectly and, thanks to his skill, her life has been transformed.

“We think 3D printing has the potential to transform the lives of many more animals – and, of course, many people, in the future and we are looking forward to playing our part.”

Contact details for referrals:

Dr Ryk Botes, Branch Partner Medivet Faversham

Email: ryk.botes@medivet.co.uk

Tel: 01795 531313

Fused Pelvis

Liz Barton — Mon, 10 Dec 2018 00:30:17 GMT

This stray cat came in with a lot of metal work in it's hindlimbs and ?bilateral FHNEs vs congenital defect of the femoral heads? Either way the abduction and extension of the hips was severely reduced.

World-first feline prosthetic paws

Arlo Guthrie — Mon, 26 Nov 2018 15:52:00 GMT

Click here to read the full story.

These images were first uploaded Jun 25, 2010, re-uploaded Nov 26 2018 after site upgrade.

World-first prosthetic implant for American Bulldog

Arlo Guthrie — Mon, 26 Nov 2018 15:35:51 GMT

Full story about the case here.

These images first uploaded Jun 11, 2010, re-uploaded Nov 26 2018 after site upgrade.

Double Sided Feet

Liz Barton — Tue, 20 Nov 2018 13:26:24 GMT

This stray SBT presented with duplicate pads and nails on the dorsal aspect of all 4 feet, mirroring normal palmar/plantar ones. It was also hermaphrodite with bilateral cryptorchidism and had a hugely undershot jaw. I wonder what the rest of the litter looked like!

Weimaraner Hindlimb Fracture

Noweia — Sun, 13 Sep 2015 09:58:53 GMT

Ed's note: First published Jan 24th 2010 and reuploaded following site upgrade.

Weimaraner + horse = mess!

I had this over the weekend, it reduced quite nicely and is awaiting definitive repair tomorrow morning.

Just one of those things look look at and think, 'Ouch!'

Hips. Normal mature dog. Picture quality.

Malcolm Ness — Mon, 07 Sep 2015 20:03:06 GMT

Picture quality

The extended ventro-dorsal view is familiar though not always easy to position. Persevere, as well positioned pictures are easier to interpret.
The femurs are parallel, the obturator formaninae are symmetrical and the sacro-iliac joints are a matching pair confirming that this is a well positioned picture.
Exposure factors are equally important - over exposure tends to obliterate detail while under exposure obscures, for example, visualisation of the dorsal acetabular rim through the femoral head.

Hips. Normal mature dog. Radiological assessment.

Malcolm Ness — Mon, 07 Sep 2015 20:01:34 GMT

Radiological Assessment

The "ball" sits well into the "socket".
The femoral heads are evenly rounded and a narrow, even and parallel joint "space" (in fact the articular cartilage) can be identified.
The skyline of the femoral neck is free from irregularity - there is no sign of osteophyte formation.
The medial flattening of the femoral head is normal - the attachment of the Teres ligament.

Hips. Normal immature dog.

Malcolm Ness — Mon, 07 Sep 2015 19:59:53 GMT

The femoral head sits deep in the acetabulum.
The femoral capital physis is still open and this makes interpretation difficult.
Note the even, parallel joint space.
There are no osteophytes.
The lucent area medial to the acetabulum is normal - this is a combination of physes and the origin of the Teres ligament.

Hips. HD. Immature dog. Frog leg view.

Malcolm Ness — Mon, 07 Sep 2015 19:58:23 GMT

This is the same dog as the previous radiograph
Note that, although close inspection reveals an irregular coxo-femoral joint "space" and rounding of the acetabular edges, this view tends to flatter the hips - if this was the only view collected, there would be a risk of misdiagnosis.

Hips. HD. Immature dog. Extended VD.

Malcolm Ness — Mon, 07 Sep 2015 19:56:20 GMT

The femoral heads sit well out of the acetabulums.
There is no even, parallel joint "space"
The edges of the acetablums are rounded and relatively indistinct.
Note that there is, as yet, no evidence of osteophyte formation.

Hips. HD & moderate OA. Mature dog.

Malcolm Ness — Mon, 07 Sep 2015 19:54:24 GMT

The femoral heads are not well seated in the acteabulums.
The joint spaces are wide and uneven.
The femoral heads are not round.
The skyline of the femoral necks is uneven due to osteophytes.
A "tidemark" of osteophytes is visible coincident with the attachment of the joint capsule on the femoral neck.
There are osteophytes filling the depth of the acetabulum.
The edges of the acetabulums are rounded and rather indistinct.
NB despite the obvious radiographic abnormalities in this case, the dog was showing no signs of hip pain, stiffness or lameness.

Hips. HD & severe OA. Mature dog.

Malcolm Ness — Mon, 07 Sep 2015 19:50:19 GMT

Whilst the osteophytes on this close-up picture might not be as florrid as can be seen on other pictures, this represents severe end-stage OA
There is no distinct femoral neck - this is probably the result of coalescence of ostoephytes over a long period leading to remodelling of bone.
Of particular interest is the lack of a joint "space". The joint space in a normal joint radiograph is, in fact, articular cartilage so we can infer from this picture that the coxo-femoral articular cartilage has eroded completely. There is, in effect, bone on bone weight bearing - inefficient and painful.
This radiograph is included to emphasise the poor correlation between florrid osteophytosis and clinical severity.

Total Hip Replacement

Malcolm Ness — Mon, 07 Sep 2015 19:26:29 GMT

Image 1

Total hip replacement (THR) is a salvage procedure.
Functional results are excellent with an expectation that the patient will achieve normal athletic activity, even work.
THR is appropriate for all dogs which cannot enjoy full, unrestricted activity following appropriate medical treatment.
THR is not just for very severely affected dogs.
THR can be performed successfully even in skeletally immature dogs
Although most patients are larger breeds, small implants are available making THR an option for Westies etc with Perthes disease.

Image 2

Many of the problems and complications with THR relate to the use of polymethylmethacrylate bone cement.
Newer designs of hip are cementless - these radiographs show a Biomedtrix BFX cementless hip in a 40Kg labrador.
The implants have a porous metallic coating into which patient bone grows providing a permanent, biomechanically sensitive and immensely strong bond.
Cementless hips are more difficult to implant than older systems demanding an exact and precise surgical technique. Some surgeons have struggled to overcome these technical challenges.

Image 3

Open leg lateral view of a cementless THR - 4 year follow up.
This view is useful in evaluating hips as it minimises interference from overlying structures.
In this case the implant-bone bond is mature, well established and stable.
The patient is a Labrador retriever that has worked three full seasons since the hip replacement performed when the patient was 16 months old.

Canine Stifle. Normal. Lateral view.

Malcolm Ness — Mon, 07 Sep 2015 19:22:19 GMT

Lateral: 4 year old Labrador retriever

Note positioning:
- Superimposition of femoral condyles
- Superimposition of fabellae
- Beam centred on stifle joint
Appropriate exposure allows definition of large infra-patellar fat shadow
- Note small triangular shaped joint fluid shadow
- Fascial planes caudal to joint are identifiable and not displaced.
Note smooth, rounded outlines to all bones.
No signs of osteophyte formation.
- It is not unusual to see what looks like an ostephyte forming at the distal pole of the patella - that is normal.
- In contrast, any irregularity on either fabella is considered abnormal.
The sizes and shapes of the joint fluid/infra-patellar fat shadows should be evaluated very carefully.
- Synovitis/joint effusion is the first sign of stifle joint OA which is most commonly caused by cruciate ligament pathology.