Hip dysplasia Flashcards
What is the heritability percentage of hip dysplasia?
20-30%
Are dogs with HD born with bad hips?
No, HD is a developmental disease as dogs are born with normal hips, but have a genetic predisposition to hip joint laxity
At what age can the inciting laxity start?
As early as 30 days old
When can HD be diagnosed clinically?
From four months old, subluxation and poor congruency between femoral head and the acetabulum.
What are the secondary changes of HD and why?
Forces are not transmitted across the joint normally, leading to overload of areas of articular cartilage resulting in degeneration, development of joint capsule thickening, periarticular fibrosis and healing of microfractures.
what is the typical distribution of clinical signs of hip dysplasia?
Bimodal - at early age (<12m) when hip laxity is seen and pain as a consequence - fibrosis stabilizes the joint, then again with OA at a later stage in life (>2yrs)
Which breed dogs are prevalent?
Medium to large breed dogs
Labrador retrievers
Clinical signs of HD?
mild stifness on rising, reluctance to jump, wiggle walk
bunny hop
Diagnosis of HD on clinical exam?
Barlow test
Bardens hip lift test
Ortolani test
Are done under sedation/anesthesia!
Radiographic changes in HD of young animals?
Acetabular coverage of femoral head should be more than 50%
Early secondary changes can be seen
! Beware of insertion of capital ligament !
Radiographic changes of HD in older animals?
Osteophytes - new bone formation
Flattening of femoral heat
Flattening of acetabulum
New bone formation of femoral neck
Thickening and/or capsule mineralization
Subluxation to completely luxoid
Treatment - conservative management - indications?
First line in young and old dogs
75% of young animals with HD will go on to have minimal gait abnormalities when 15months old
What is part of conservative treatment in HD?
Rest
Weight control
Regular low inpack excercise, hydrotherapy
NSAID
Nutraceuticals, chondroprotective drugs
Preventative surgical treatment?
TPO - tripple pelvic osteotomy
DPO - Double pelvic osteotomy
Pubic symphyiodesis
What patients can be included or excluded for a TPO?
What is the outcome?
TPO - tripple pelvic osteotomy
Only young patients (<9m) without secondary (OA) changes, and an angle for eduction <30 degrees and >10 degree subluxation
Good, excellent result in 76-92% of cases
What is a DPO? Compared to a TPO?
Double pelvic osteotomy - bilateral operation
Most favourable prognosis in patients having minimal degenerative changes, and angle reduction >45 degrees and angle of subluxation <15 degrees
What is pubic symphysiodesis? Patient inclusion criteria?
(Juvenile) Pubic symphysiodesis - electrocautery is used to damage the pubic symphysis in young puppies, causing altered pelvic development.
Patients must be younger than 16w (max 18w in giant breeds)
Patients MUST be neutered due to reduced pelvic inlet!
Salvage procedures for HD?
FHNE - femoral head and neck exision/ostectomy
THR - Total hip replacement