Paediatric orthopaedics - the big three

Question 1

What are the big three

Answer 1

DDH - Developmental Dysplasia of the Hip

Perthes disease

SUFE - Slipped Upper Femoral E piphysis

Question 2

What can DDH lead to

Answer 2

Developmental dysplasia of the hip can lead to arthritis

Question 3

What age does DDH usually affect

Answer 3

newborns

Question 4

What age does Perthes disease normally affect

Answer 4

primary school age

Question 5

what age does SUFE usually affect

Answer 5

Slipped upper femoral epiphyses - End of primary, beginning of secondary school

Question 6

Where in the world is DDH - developmental dysplasia of the hip - most common

Answer 6

inuits - people who live in the arctic regions

Question 7

Which gender is DDH more common in

Answer 7

Females 6:1 Males

Question 8

Which hip is more commonly effected by DDH

Answer 8

Left hip - babies more commonly lie on their left side

Question 9

What are the risk factors for DDH

Answer 9

first born
oligohydramnious - less fluid in the fluid filled sac the baby is in so the child is more likely to have renal problems and therefore they cannot kick around as much and have more chance of dislocated hip
Breech presentation - born feet first
Family history
other lower limb deformities
Overweight babies

Question 10

What are the clinical features of DDH

Answer 10

Ortolani’s sign - as you abduct the hip, the hip pops into the socket
Barlows sign - apply a downward pressure over the knee with your thumb. If the hip is unstable, the femoral head will slip out of the acetabulum, producing the palpable sensation of the hip dislocating.

Piston motion sign - push on hip and you can feel it moving

Hamstring sign - flex thigh onto stomach and you should not be able to extend the knee unless the hip is dislocated

Question 11

Why is Xray not done in new borns to look for DDH

Answer 11

Head of femur does not ossify until 3 months old at least so ultrasound has to be used

Question 12

What is the treatment of DDH

Answer 12

If the DDH is caught early <3 months old - simple splint will be effective - pavlick harness

Closed reduction and spica cast if between 3 months and a year old

Over 18 months - open reduction with femoral shortening with or without peri-acetabular osteotomy

Over 6 years and bilateral - no treatment

Over 10 years old and unilateral - leave alone

Question 13

What is the correlation between age of diagnosis of DDH and effectiveness of treatment

Answer 13

The younger DDH is diagnosed, the easier and more effective the treatment will be

Question 14

Who is perthes disease more commonly seen in

Answer 14

Male - 10:1
Primary school age - 3,4,5
Short stature
Limp
knee pain on exercise
stiff hip joint
systemically well

Question 15

How does DDH occur

Answer 15

Avascular necrosis of the hip

Question 16

What happens in perthes disease

Answer 16

the blood supply to the head of the femur is interrupted. The femoral head then “necroses,” or loses blood supply, which weakens the bone and can lead to multiple fractures. Next, the bone is taken up by the body, or resorbed, which can lead to a complete collapse of the femoral head - Bone becomes soft and then the head of the femur collapses down and the space between the acetabulum and the femur increase

Question 17

What is the correlation with the shape of the femoral head and prognosis in perthes disease

Answer 17

The rounder the head the better - perthes can cause flattening of the femoral head

Question 18

What is the correlation between age and prognosis in perthes disease

Answer 18

Younger diagnosis - better outcome

Question 19

What is the Herring grade

Answer 19

The more collapsed down, the lateral pillar (lateral part) of the head was, the more severe, the perthes disease was

Question 20

How is perthes disease treated

Answer 20

Very young do not need treatment

Mantain hip motion
analgesia
restrict painful activities
Osteotomy in selected older children over 7

Question 21

What happens in an osteotomy

Answer 21

The head of the femur is broken and then contained into the acetabulum - points into the socket

Question 22

What is used for diagnosis of perthes disease

Answer 22

X-ray

Question 23

Who is SUFE - slipped upper femoral epiphysis more common in

Answer 23

Teenage boys - 9-14 years old slightly more than females

Mainly overweight

Question 24

What is acute SUFE

Answer 24

symptoms for less than 3 weeks

Question 25

What is chronic SUFE

Answer 25

symptoms more than 3 weeks

Question 26

What is an unstable SUFE

Answer 26

Unable to weight bear - bad prognosis

Question 27

What is stable SUFE

Answer 27

able to weight bear - good prognosis

Question 28

What is the presentation of SUFE

Answer 28

pain in hip or knee
externally rotated posture and gait
reduced internal rotation especially if the hip is flexed up

Question 29

How is SUFE investigated

Answer 29

X-ray

Question 30

What is the treatment for SUFE

Answer 30

Surgical - screw through the centre of bone and through the neck of the femur - bone grows across the growth plate and stops the slip getting worse

In severe unstable slips can do open reduction but avascular necrosis risk is high

Question 31

What are the risk factors of SUFE

Answer 31

avascular necrosis
chondrolysis - damage to the cartilage
deformity
osteoarthritis
slip possibility on the other side
limb length discrepancy
impingement

Question 32

What is the correlation between stability of slip and risk of avascular necrosis in SUFE

Answer 32

The more stable the slip is, the less risk of A vascular necrosis