Salvage Procedures Flashcards
Define arthroplasty
‘Excision’ or ‘replacement’ of joint
Define arthrodesis
Surgical fusion of a joint
(Ankylosis = non-surgical slow natural fusion)
What are the 2 types of arthroplasty and what species can we do this in?
- Excision arthroplasty:
- Dogs, cats (removal of a surface)
- Joint replacement arthroplasty:
- -hip (dogs & cats), elbow & stifle (dogs)
Which species can we do a arthrodesis in?
All species - jont dependant
Which species ccan we do amputation in?
Dogs and cats: limbs, digits, tail
Small caged pets: limbs, tails
Name 3 indication in the hip for an arthroplasty (4)
- Dysplasia = unmanageable juvenile pain
- Persistent luxation
- Non-reconstructable articular fracture
- Intractable degenerative joint disease = pain
Name 5 effects of excision arthroplasty (7)
- Should be pain free
- Instability of the joint = abnormal movement
- May have reduced range of motion and regional muscle
atrophy (cannot extend the hip as much) - Mechanical lameness
- Morbidity highest in first 1-2 months
- Outcome can be variable / unpredictable
What is a lifelong effect of a replacement arthroplasty?
Lifelong ppoteential morbidity
Excision arthroplasty, where is it:
A) Common?
B) Very rare?
C) Occasional?
A) Hip
B) Shoulder
C) Temporomandibular joint
What are the benefits of a femoral head and neck excision?
- Technically simple, cheap, few complications
What are the 2 affects of “body size” on a fermoral head and neck excision?
What factors inflience the outcome of a femoral head and neck excision?
•Patient temperament
- obese, sedentary dogs (muscles less strong) do less well than fit active individuals
•Age
- younger animals adapt better than older patients
- Chronicity, disuse muscle atrophy = poorer outcome
- Bilateral condition or concurrent problems?
- Two hips that are poor - harder to manage
- Do not do in a large dog
What are the crucial “important factors” in a femoral head and neck excision?
•Accurate and complete excision of the femoral neck
- Remember that there is a degree of anteversion and
hence more of the neck must be removed caudally - When you make a cut from a cranial aspect need to take off more caudally due to the anteversion
- Maintain the lesser trochanter with the insertion of the ilio psoas muscle, an important hip flexor
- Early and intense physiotherapy with appropriate analgesia
What is the procedure for a femoral head and neck excision?
- Standard craniolateral approach to hip
- Disarticulate hip
- Take out the hip
- Rotate femur 90 degrees to table – see femoral head and neck
- Cut perpendicularly down onto base of femoral neck
- Best to use an oscillating saw.
- Preserve greater and lesser trochanters.
- Visualise & digital palpation of cut neck for quality of cut.
- Entire femoral neck and head must be removed
What does this show?
The end results of a femoral head and neck excision
Where can we do a replacement arthroplasty in a cat?
Hip
Where can we do a replacment arthoroplasty in a dog?
- Hip
- Elbow
- Stifle
What is the “ideal patient” for a total hip replacement?
- Painful hip (non-responsive to medication)
- 10-40kg dog
- Has had no previous hip surgery – scarring or if recent there is a chance of infection
- Previously active lifestyle
- Sensible, well-trained dog
- Compliant owners - rest
- Can afford cost
- Can afford / cope complications
If a client can’t afford a total hip replacement, what can we consider?
FHNE
What are the different ways/systems of doing a total hip replacement? (3)
Cemented systems: polmethylmetha-crylate (PMMA)
Cementless systems: bone ingrowth
Hybrid systems
What type of hip replacement?
Biomedtrix
BFX
Biological fixation
What type of hip replacement?
CFX
What type of hip replacement?
Hybrid
What can be seen about how this hip replacement was done?
Cement around the stem
What is the complication rate of a total hip replacment? What is the outcome of this?
5-10% but potentially disastrous
May have to convert the surgery into a femoral head and neck excision
Name some toal hip replacement complications (8)
- Infection: - Surgical
- Haematogenous: any stage
- Dislocation: esp. First 8 weeks. See X-ray. Can be put back in but may come back out – especially If associated with cup poorly placed
- Fracture: - Any stage
- ‘Stress riser’
- Aseptic Necrosis of implant (cemented systems) : any stage
- Loss of bone cement or interface
- Technical error in preparation of bone, or cement failure of bone-cement interface failure of cement-implant interface
- Or through accumulation of ‘wear’ products
What is the complication rate of a toal elbow replacement and what are the recovery options?
High 20% complication rate
Recovery option- arthrodesis, amputation, euthanasia
If it fails – not got much choice
What are the 6 Principles of Arthrodesis?
- Absolute stability, ideally through compression
- Remove cartilage from contact areas
- Contour opposing joint surfaces
- Cancellous bone graft
- Fuse at a functional angle
•Plates are designed to have a natural correct angle
6.Temporary external support
- Rarely needed
- Complications are risky
At what position is arthrodesis more disabling?
Proximally
What is a common result of stifle and elbow arthrodesis?
Poor function
What does this show?
Arthrodesis
Name 4 common amputation reasons (5)
- Neoplasia - malignant or locally invasive
- E.g. osteosarc. But by the time of diagnosis the chances are there are lung mets
- Trauma - excessive tissue damage including markedly comminuted fractures particularly those involving joints
- Paralysis – e.g. brachial plexus avulsion
- Unmanageable joint conditions, intractable pain,congenital deformity
- (Financial reasons)
How do we undergo an oncological surgery ‘limb sparing’ procedure?
- Oncological surgery
- Resect bone with appropriate margins
- Cortical allograft used to maintain limb length
- (Or excised tumour bone pasteurised and replaced the bone)
- Arthrodesis if near joint e.G. Distal radius
- Chemotherapy
- Complications
What is Transcutaneous Prosthetics (ITAP)?
Prosthesis retained in bone
Transcutaneous Prosthetics (ITAP):
A) Advanatge?
B) Disadvantage?
A) Avoids pain / stump tissue issues and proprioceptive issues that arise in people wearing standard prosthetic
B) Difficult to get soft tissues to form seal around metalwork
What do we need to consider with an amputation? (5)
- Presence of bilateral problem or other orthopaedic disease
- Condition / weight
- Age
- Owner
- Temperament
Name 3 general principles with an amputation (5)
- Neoplasia - adequate margin of excision
- Know the extent of the tumour
- Cut bone short and leave excess skin and soft tissue to cover
- Peri-neural local anaesthesia and sharp incision through nerves (new scalpel blade – not scissors!)
- Careful haemostasis and meticulous surgical closure to eliminate dead space
- Local analgesia / nerve block post-operatively
How many ligatures do we need to place on a fermoral artery?
At least 3
What are the amputation sites of the forelimb? (2)
- Forequarter amputation
- Mid-humerus
What are the amputation sites of the hindlimb? (3)
- Prox. 1/3rd femur
- Disarticulation at hip
- Hemipelvectomy
What is the effect of amputating digit 3/4?
More lame
What is the recommendation for digit removal? What do we need to apply post surgery?
- Often recommended to remove cartilage/condyle – rarely causes a problem if left
- Careful dressing post-surgery
What length of tail so we amputate?
Should leave enough to cover perineum
What is the normal weight distribution HL:FL?
40:60
What is the gait adaption for a forelimb adaptation?
Take more weight on the HL
What is the gait adaptation for a HL amputation?
More weight on FL
Do dogs do better withh a FL or HL amputation?
HL
When is amputation indicated?
If the limb is not salvageable, there is intractable pain, neoplasia or a failure of first line treatment
