Ortho - Hips, elbows and cruciates Flashcards
what is hip dysplasia?
a common inherited developmental disease characterised by laxity of the hip joint
are hips lax from birth?
no, puppies are born normal - laxity apparent from 4-5 months
which animals are commonly affected by hip dysplasia?
most commonly large and giant breed dogs
also affects small breeds and cats
when are the earliest signs of hip laxity usually seen?
4-5 months
what is the usual signalment for hip dysplasia?
4-12 months at first presentation
second phase affects adults - present with arthritis secondary to hip dysplasia - no laxity
what is the usual history associated with hip dysplasia?
hindlimb stiffness and difficulty mobilising, affecting both legs, bunny hopping, adducted hindlimbs
what can we see on gait analysis which is characteristic of hip dysplasia?
short stride on hindlimbs
lateral sway to avoid full stride - uses back
bunny hopping
adducted hindlimbs
what might we see upon orthopaedic examination of a patient with hip dysplasia?
muscle atrophy (quadriceps)
pain on hip extension
crepitus
clunking
what radiographic views are useful in diagnosing hip dysplasia?
v/d extended
frog leg
lateral pelvis
which manipulation tests can be used to test for hip dysplasia?
ortolani test
Bardens hip lift test
in which cases is the ortolani test not useful?
older dogs with arthritis
negative in cases of dislocation - will be unable to relocate joint
how is the Bardens hip lift test performed?
patient in lateral
hip is levered out of acetabulum to see how much ‘bounce’ is achieved
can the Bardens hip lift test be done on a conscious patient?
no - patient must be heavily sedated/under GA - painful test
what is classed as an abnormal Bardens hip lift result?
> 0.5cm
what are the available treatment options for hip dysplasia?
conservative managament
myotomies
growth plate fusion
osteotomies
THR
FHNE
what type of growth plate fusion is carried out on patients with hip dysplasia?
juvenile pubic symphysiodesis
which patients are suitable for growth plate fusion/osteotomy?
young patients with early diagnosis
what is involved in conservative management of hip dysplasia?
restricting exercise to lead-only - short regular walks, no off-lead
hydrotherapy
controlling food intake to restrict weight and slow down growth
judicious use of NSAIDs and other medication
can conservative management improve degree of subluxation?
not shown to improve - remains same or worse
what is juvenile pubic symphysiodesis?
iatrogenic closure of the pubic symphysis
how is juvenile pubic symphysiodesis achieved?
electrocautery to create thermal necrosis
what does juvenile pubic symphysiodesis result in?
growth of acetabulum which increases dorsal cover of the femoral head
why is juvenile pubic symphysiodesis rarely done?
must be done when patient is very young, during early growth phase - rarely identified this early
why is it important to neuter dogs who have had juvenile pubic symphysiodesis?
to ensure they are not bred from to avoid passing the condition on
when should a triple/double pelvic osteotomy be performed?
by 6-7 months, no DJD present
why is a triple/double pelvic osteotomy not commonly performed?
most cases are identified too late for this approach
how do we identify patients who are suitable for a triple/double pelvic osteotomy?
good clunk on ortolani test
what is the aim of a triple/double pelvic osteotomy?
increase dorsal cover of the femoral head
how is a triple/double pelvic osteotomy performed?
cutting into bone of ilium, pubis and ischium and rotating bone round to improve dorsal cover of the femoral head
what are the possible complications of a triple/double pelvic osteotomy?
screw pullout
screw breakage
- do not usually require correction
what is the success rate of triple/double pelvic osteotomy?
90% success
does a triple/double pelvic osteotomy prevent arthritis?
no - may still require salvage surgery later on
what type of procedure is a FHNE?
salvage procedure - pseudoarthrosis
what is a pseudoarthrosis?
fills in with bone and fibrous tissue
how can we improve outcome after a FHNE?
encourage exercise after surgery - outcome improved by good post-op rehabilitation programme
what is denervation?
removal of the nerves on the dorsal acetabulum - not commonly done
when might denervation be carried out?
with cost constraints - cheaper and provides pain relief
what are the aims of a THR?
pain relief
return of high level function
what are the indications for THR?
end-stage hip arthritis
hip dysplasia (younger dogs)
what are the 2 main types of prosthesis in THR?
acetabular prosthesis
femoral prosthesis
what are the overall steps of the surgical procedure for a THR?
femoral head excision
ream acetabulum and femur
cement acetabulum and femur
place “femoral head”
reduce hip
take bacterial swab
suture joint capsule, routine closure
which approach is used during a THR?
craniolateral approach
what does it mean to ‘ream’?
remove cartilage
why should the joint capsule be sutured as part of a THR?
helps reduce the chance of dislocation following surgery
why should we take a bacterial swab during a THR?
to ensure no contamination of the site during surgery
what are we assessing on the immediate post-op radiographs after a THR?
positioning of femoral stem and acetabulum
cement fill - no fissures, leakage
what are we assessing on long-term radiographs after a THR?
position of femoral stem and acetabulum
periosteal reaction
cement/bone interface
when should post-op radiographs be taken for a THR?
immediately post-op and 6 weeks post-op
what are the possible complications after a THR?
fracture
loosening
dislocation
infection
subsidence
cement granuloma
neurological issue
what are the 2 main type of hip implant available?
cemented vs uncemented
which factors influence the type of THR performed?
surgeon preference, shape of femur/acetamulum, equipment available in practice
what is involved in post-op care after a THR?
cage
lead walks only
ehmer sling
hobbles
avoid slippery surfaces, avoid jumping
what occurs at the end of the post-op period?
re-examination and further radiographs taken - ensure no complications have occurred
how can loosening of the THR implant be seen on radiographs?
increased lucency between the bone and cement
how can infection of the THR implant be seen on radiograph?
periosteal reaction
what should occur is progress is satisfactory at the 6 week check?
gradual return to normal exercise over the next few months
what is the most common cause of forelimb lameness in dogs?
developmental elbow disease (DED)
what type of abnormalities can be involved in developmental elbow disease?
fragmented medial coronoid process of the ulna
osteochondritis dissecans
joint incongruity
ununited anconeal process of ulna
why does joint incongruity occur in the elbow?
asynchronous growth of radius and ulna
what does developmental elbow disease result in?
varying amounts of elbow osteoarthritis
can different abnormalities of developmental elbow disease occur at the same time?
yes
what is the common signalment for elbow dysplasia?
large breeds e.g. labradors, rottweilers, retrievers, BMDs
6 months and older (at presentation)
males over-represented - females also affected
when might a dog present older with developmental elbow disease?
if have arthritis secondary to elbow disease
what are the signs of elbow dysplasia?
lameness
elbow effusion if severe
decreased ROM
pain on extremes of flexion and extension
what is the common history for a dog with elbow dysplasia?
low grade mild lameness, bilateral
which radiography views are helpful in the diagnosis of DED?
cranio-caudal, medio-lateral and flexed lateral views of the elbow