Hip Flashcards
The hip is a diarthrodial joint. What does this mean?
Articulating bones separated by a fluid-containing joint cavity
(Most common joint)
What are 2 developmental conditions of the hip?
Hip dysplasia
Legg-Calve-Perthe’s disease
What are some acquired conditions of the hip joint?
Osteoarthritis
Neoplasia
Immune mediated arthropathy
What are some traumatic conditions of the hip?
Coxofemoral luxation
Fractures of femoral head and neck
Fractures of acetabulum
What causes hip dysplasia?
Laxity and instability of hip joint
Causes osteoarthritis
Results in pain as femoral head hits acetabular rim
What are the risk factors for hip dysplasia?
Large breed dogs Devon Rex Cat Genotype Bodyweight Nutrition Growth rate
What breed cat is predisposed to hip dysplasia?
Devon Rex
At what age do the clinical signs of hip dysplasia subside?
12-18 months
Dogs present young (<12 months)
What two ages of dogs usually present with hip dysplasia?
Young dogs - <12 months
Adult dogs with osteoarthritis secondary to HD
What are the clinical signs of young dogs (<1) with hip dysplasia?
Unilateral/bilateral HL lameness Bunny hopping Reluctance to exercise Pain upon hip/extension flexion Positive Ortalani test
What is the Ortolani test?
Used to diagnose hip dysplasia
Under sedation, hip manipulation will cause subluxation and popping
What are the clinical signs of hip dysplasia in adult dogs?
Stiffness after rest/exercise Bunny hopping Usually bilateral lameness Pain upon joint manipulation Reduced ROM
How is hip dysplasia diagnosed?
History
Clinical signs
Radiography
What EARLY radiologic changes are seen with hip dysplasia?
Wide joint space with medial divergence
centre of femoral head lateral to dorsal acetabular edge
What secondary radiologic changes are seen with hip dysplasia?
New bone formation of femoral neck (Morgan line)
Remodelling of femoral head/neck and cranial acetabular rim
What are the treatment options for hip dysplasia?
Conservative - exercise restriction, NSAIDs
Surgery (if non-responsive to conservative management)
What surgery can be performed to treat hip dysplasia?
Total hip replacement (all ages- Tx of choice)
Femoral head and neck excision (all ages)
(Triple pelvic osteotomy, juvenile pubic symphisiodesis - young dogs only)
What are the indications for femoral head and neck excision surgery?
Legg-Calve-Perthe’s disease
Unreducible fractures
Hip dysplasia
What are contraindications for a total hip replacement?
Chronic systemic illnesses
E.g. skin problems
What are the disadvantages of a total hip replacement?
Expensive!
Cannot be done if chronic systemic illness (e.g. skin problems)
What breeds are prone to Legg-Calve-Perthe’s disease?
Small breeds
WHWT, Manchester terriers
What is the pathogenesis of Legg-Calve-Perthe’s disease?
Ischaemia of femoral head bone
Leads to deformity and collapse
What age dogs are usually seen with Legg-Calve-Perthe’s disease?
Young (5 months old)
What are the clinical signs of Legg-Calve-Perthe’s disease?
Unilateral lameness (usually) Young dog (5 months) Pain and crepitus upon hip manipulation
How is Legg-Calve-Perthe’s disease diagnosed?
Radiography (frog leg and VD extended)
What is the treatment for Legg-Calve-Perthe’s disease?
Surgery > conservative
Femoral head and neck excision (Tx of choice)
Total hip replacement
(Post-op rehab very important)
What fractures can be seen in the proximal femur?
Capital and capital physical fractures
Femoral neck fractures
Greater trochanter fractures
In what age animals are capital physeal fractures usually seen?
Young - 4-7 m/o
What are the clinical signs of capital physeal fractures?
Young animal (4-7 months)
Pain upon hip maniuplation
History - secondary to trauma
What is the treatment for capital physeal fractures?
Surgery
3 divering/parallel K or arthrodesis wires
What is the most common luxation in small animals?
Coxofemoral (hip)
What animals are usually affected by coxofemoral lunation?
Animals >12 months
Following major trauma e.g. RTA
Coxofemoral lunation can occur in any direction, but which is most common?
Craniodorsal
What are the clinical signs of coxofemoral lunation?
Leg carried in flexion - stifle out, hock in
Greater trochanter more prominent - look for asymmetry
How is coxofemoral lunation diagnosed?
History and clinical signs
Radiography (2 views - rule out other problems such as capital fractures and hip dysplasia)
What is the treatment for coxofemoral lunation?
Closed reduction (manipulation of the joint without incising) unless hip dysplasia, or avulsion fracture If re-luxation occurs then open reduction and stabilisation
Within what timeframe of a coxofemoral lunation should a closed reduction be performed? How is this done?
Within 48 hrs (if over this time = surgery)
Under GA - tie dog to table
(Radiograph after to ensure reduction)
What may cause reluxation of the coxofemoral joint after closed reduction?
Haematoma
Fragments in acetabulum
