Paediatric Hip Disorders Flashcards
What is Developmental Dysplasia of the Hip (DDH)?
abnormal development resulting in dysplasia and possible subluxation/dislocation of the hip
What type of dysplasia can occur in DDH?
shallow or underdeveloped acetabulum
Is DDH more common in males or females?
Most common in females
- especially in left hip
What ethnicities are more likely to develop DDH?
more commonly in Native Americans and Laplanders
(due to way of carrying children, does not promote normal growth)
Rarely seen in African patients - Baby wrap carrying method promotes correct growth
Why does DDH occur?
Initial instability thought to be caused by:
- maternal and fetal laxity
- genetic laxity
- intra-uterine position
- postnatal malpositioning
Why is normal growth and development hindered in DDH?
Correctly positioned femoral head stimulates normal head and acetabular growth
In DDH the femoral head was never in the right position, or it dislocated and hindered growth
What actions make up the “safety position” of the hip?
Hip flexion
Hip abduction
What are the risk factors for developmental dysplasia of the hip?
- Firstborns
- Females (6:1)
- Breech presentations
- Family history
- Oligohydramnios (deficiency of amniotic fluid)
At what stage do patients with DDH usually present?
Abnormality on screening (early)
Limping child (late) “Trendelenberg Gait”
Pain later in life (secondary arthritic changes)
Why is Ultrasound more useful in investigating DDH than radiographs?
Not much will show up on radiograph
Young children = more cartilage which has not ossified and therefore wont show up
By using the “H Lines” on a normal pelvic radiograph, in which quadrant should the femoral head lie?
Inferior medial
at least 90% should be in here
What 3 bones come together and are joined by the tri-radiate cartilage ?
Ilium
Ischium
Pubis
At what age do patients with DDH usually present?
Between birth and 2 years
can (rarely) be diagnosed in utero
At what age does Perthes disease usually affect children?
Between 4 and 8 years old
What age are patients who get a slipped upper femoral epiphysis (SUFE)?
Usually adolescents 10-16 years old
Describe the Barlow’s Test for clinical examination of suspected DDH
Push Backwards to try to dislocate hip
Describe the Ortolani Test for examination of suspected DDH
the hip is already OUT
=> abduct it and push femoral head forward into acetabulum
How is an early presentation of DDH treated?
PAVLIK HARNESS
- holds hips in “safety position”
- 23hrs a day for 12 weeks until US = normal
- Night time splinting for a few more weeks
How is a late DDH presentation treated?
SURGERY
Closed reduction
+/- tenotomies (cutting tendon)
+ spica (cast with plastic bar across bottom)
Open reduction
+ osteotomies (cutting bone for realignment)
+ spica
What tendons are usually cut during a closed reduction DDH procedure?
Psoas or Quad tendon
What bones are cut during an open reduction DDH surgery?
Pelvis, Proximal femur or BOTH
What is Reactive synovitis?
Inflammation of the synovium
often secondary to a viral illness
How do patients with reactive synovitis usually present?
- Hx of viral illness
- Limp
- hip/groin pain (may refer to knee but uncommon)
- Hip lying flexed/externally rotated
- Pain at end range of hip movements
- systemically well, apyrexial
What is used to help diagnose reactive synovitis?
Kocher’s criteria
Ultrasound +/- aspiration
What are Kocher’s Criteria?
Fever >38.5
Refusal to weight bear
CRP >20
Serum WBCs >1200/mm^3
What is the purpose of Kocher’s criteria?
Distinguishes between Reactive synovitis and septic arthritis
How is reactive synovitis treated?
- Self-limiting condition
- Analgesia / NSAIDs
- Repeat review / admission if any concern
What is septic arthritis?
Intra-articular infection of the joint
SURGICAL EMERGENCY
Why is septic arthritis a surgical emergency?
- High bacterial load that causes sepsis
- proteolytic enzymes destroy joint cartilage
- osteonecrosis of the hip due to increased pressure
How do patients with septic arthritis usually present?
- Short duration of symptoms
- Unable to weight bear and hip/groin pain
- Hip lying flexed/externally rotated
- Severe hip pain on passive movement
- Usually pyrexial but children may be haemodynamically stable
Why does hip lie flexed/externally rotated in conditions such as painful septic arthritis?
Maximises joint space
What usually causes septic arthritis?
- direct inoculation from trauma or surgery
- haematogenous seeding
- extension from adj. bone (osteomyelitis)
- can develop from contiguous spread of osteomyelitis
How does septic arthritis usually spread in babies/children ?
- spread from highly vascular metaphysis
- common in neonates who have transphyseal vessels that allow spread into the joint
What joints are usually affected in septic arthritis in children?
joints with intra-articular metaphysis include:
- hip
- shoulder
- elbow
- ankle
What organism predominantly affects neonates in septic arthritis?
Streptococcus
What organism most commonly affects infants/children/adolescents and adults in septic arthritis?
Staphylococcus aures
What organism is usually responsible for septic arthritis in IVDUs?
Pseudomonas / atypical organisms
What blood tests are important in septic arthritis?
Blood tests (FBC, CRP +/- ESR)
Blood cultures!!!
What other investigations would you do in septic arthritis?
Kochers criteria
Radiographs to rule out other pathologies
Ultrasound +/- aspiration (usually in theatre)
How is septic arthritis treated?
- OPEN SURGICAL WASHOUT
- Repeat washout if not improving
- Antibiotics for 6 weeks
What is Perthes disease?
Idiopathic avascular necrosis of the hip
Are males or females more likely to develop Perthe’s disease?
Males
5:1
Perthe’s disease occurs more in lower socioeconomic classes. TRUE/FALSE?
TRUE
Is Perthe’s disease usually bilateral?
Can present in both hips but NOT usually at same time
Describe the pathophysiology of Perthe’s disease
- osteonecrosis secondary to disruption of blood supply to femoral head
- revascularization
- subsequent resorption and later collapse
What are the 4 stages in Perthe’s disease?
Initial
Fragmentation
Reossification
Remodelling
What factors affect prognosis in Perthe’s disease?
Age
younger at presentation = better prognosis
How do patients with Perthe’s disease usually present?
- Gradual onset of painless limp
- Sometimes intermittent groin pain (or knee/thigh)
- Hip stiffness
- int rotation and abduction
- Limp (Trendelenberg/Antalgic Gait)
What imaging modalities are used in Perthe’s investigation?
Radiographs
MRI
due to patient being older => these modalities can be used
How is Perthe’s disease treated non-surgically?
AIM = keep femoral head round whilst the process self-terminates
- Restrict weight-bearing
- Maintain range of movement with physio
- No evidence for bracing
How is Perthe’s disease treated surgically?
YOUNG patients with severe disease and deformity
=> Femoral and pelvic osteotomies
OLDER patients with secondary osteoarthritis
=> Total hip arthroplasty
How is a slipped upper femoral epiphysis (SUFE) actually defined?
slippage of the metaphysis relative to the epiphysis
What are the risk factors for a SUFE?
- Male
- Obesity
Endocrine disorders:
- Growth hormone deficiency
- Panhypopituitarism
- Hypothyroidism
How does a patient with a SUFE usually present?
- Groin pain (or knee/thigh)
- Limp
- Externally rotated foot
- Antalgic Gait
- Obligatory external rotation on hip flexion
How does a SUFE usually appear on an X-Ray?
Like ice-cream falling off the cone
How is a SUFE treated surgically?
Percutaneous pinning of the hip
+/- pinning of the other side for prophylaxis
+/- open reduction if a very severe slip
