Hip Dysplasia - advanced nursing Flashcards
What is hip dysplasia?
a common inherited, developmental disease of the hip joint
How is hip dysplasia characterised?
hip laxity or instabilty and development of osetoarthritis
What breeds are clinical signs more apparent in?
large breeds such as labradors, german shpeherds and golden retrievers
When does laxity become apparent?
4-5 months old
What does laxity allow the hip to do?
subluxate
What is axity influenced by?
size of dog, rate of growth, diet, and exercise
What does laxity of the hip result in?
inflammation and pain
What does inflammation of the joint lead to?
increase in joint fluid and thickening of the joint capsule
What ligament can become stretched or ruptured allowing subluxation or laxity?
round or teres ligament
What happens to the femoral headdue to laxity?
it becomes flattened with new bone produced at the margins of the head and around the femoral neck
What are common presenting complaints with a hip dysplasia?
bunny hopping, difficulty rising, pelvic limb lameness or stiffness, exercise interolerance, clicking or clunking of the hips
What is crepitus?
hip grinding as hip taken through range of motion, felt with hand over hip joint
What might you see on orthopaedic examination?
muscle atrophy, pain on hip extension and abduction, crepitus, clunking, lateral sway, instability
Why might a hip ‘clunk’?
it is the hip popping back into place
What is a lateral sway?
When the dog tries to protect the hips and uses the spine to propel the pelvic limbs forward
What radiography views would you do to diagnose hip dysplasia?
orthogonol, ventrodorsal extended leg and frog leg
How is hipdysplasia diagnosed using radiographs?
identifying hip subluxation and secondary osteoarthritis
What severity of hip dysplasia can ultrasound diagnose?
early detection of dogs with mild to moderate dysplasia
What is an example of palpation tests for diagnosis?
ortolani test
What does the ortolani test mimic?
weight bearing
What is the angle of reduction?
when the femur is taken away from midline and pops back in, the angle this occurs at is the angle of reduction
What is the angle of subluxation?
when you bring the femur backto midline and the hip subluxates, the anglethis occurs at is the angle of subluxation
What does a positive ortolani test suggest?
hip laxity
What does a negative ortolani test suggets?
complete dislocation
What is the bardens hip lift test?
when you try to lever the hip out of the acetabulum and see how much bounce there is
What is abnormal with a bardens hip lift test?
more than half a cm of bounce
What are the treatment options for hip dysplasia?
- non-surgical
- myotomies
- growth plate fusion
- osteotomies
- total hip replacement
- femoral head and neck excision
When is surgical treatment considered?
- significant clinical signs
- failure to respond to conservative management
What is involved in conservative treatment?
- restricting exercise to leash only
- introducing hydrotherapy
- controlling food intake to restrict weight gain and slow down growth
- NSAIDs and other meds
What is the first line of treatment?
conservative treatment
What dogs might be considered for conservative management?
younger dogs
What lifestyle adjustments can be made?
weightloss, exercise, hydrotherapy
What surgical management options are there?
- growth plate fusion
- osteotomies
- total joint replacements
- ostectomies`
What is juvenile pubic symphysiodesis?
improves coxal joint congruecy in clinically affected immature dogs before secondary arthritic changes develop
What does symphysiodesis imply?
fusion of a symphysis, which is achieved by the use off electrocautery
What types of dogs is juvenile pubic symphysiodesis performed in?
skeletally immature dogs
What does triple or double pelvic osteotomy iincrease?
dorsal coverage of the femoral head,corrects subluxation and restores the hips weight bearing surface area
Who would be a suitable candidate for triple or double pelvic osteotomy?
dogs with moderate hip laxity with an angle of reduction of less than 35 degrees on an ortolani test, painful hips, no or minimal osteoarthritis and young (between 4 and 8 months)
What happens during a triple or double pelvic osteotomy?
pelvis is cut in two or three places freeing the acetabulum which is rotated 20 degree
Which 3 places are cut during a triple or double pelvic ostetomy?
pubis, ischium and ileum
What type of procedure is a femoral neck and head excision?
salvage surgery
What happens during a femoral head and neck excisional surgery?
femoralhead and neck removed to allow pseudoarthrosis to form
What post-operative management is done after femoral head and neck excision surgery?
rapid return to exercise, physiotherapy after sutures removed
What complications can occur after a triple or double pelvic osteotomy?
screw pullout or screw breakage
What is the aim for total hip replacement?
pain relief and high levelfunction
What are the indications for total hip replacement?
hip arthritis and hip dysplasia
What is the success rate for cemented total hip replacement?
90-95%
Why are cemented THR hard to revise?
cement has to be chipped away or osteotomsation of the femur to retrieve all foreign material
What are examples of cemented systems for THR?
bardet,new generation devices
What are examples of non-cemented systems for THR?
biomedtrix BFX, zurich, helica
What happens in a non-cemented THR?
acetabulum is reamed out to fit a new femoral head
What complications can arise from a non-cemented total hip replacement?
aspetic and septic loosening,fracture and neurological
What is the zurich ceementless system? (KYON)
interlocking screws used
What are the advantages of the kyon system?
easier to revise as no cement, less chance of subsidence due to locking system
What is the helica hip?
femoral neck is preserved as the implant and is screwed into the bone
What complciations can arise from total hip replacements?
fracture, loosening, dislocation, infection, subsidence, cement granuloma, neurlogical, luxation, osteomyelitis,implant failure, sciatic neuropraxia
