Children's Orthopaedics

Question 1

Is a child’s skeleton the same as an adults?

Answer 1

No, it is not just a mini skeleton it is structurally different

Question 2

How many bones are there in a child’s skeleton?

Answer 2

270

Question 3

What is the other name for physis?

Answer 3

Growth plates

Question 4

What happens at the physis?

Answer 4

Bone growth, it is the zone of elongation

Question 5

By what process do flat bones develop?

Answer 5

Intramembranous ossification

Question 6

By what process do long bones develop?

Answer 6

Endochondral ossification

Question 7

What is the difference between intramembranous and endochondral ossification and when is each used?

Answer 7

With endochondral ossification the mesenchymal cells become cartilage before they become bone but in intramembranous there is no cartilage involvement

Endochondral= long bone development
Intramembranous= flat bone development

Question 8

Describe intramembranous ossification

Answer 8

Condensation of mesenchymal cells which differentiate into osteoblasts and an ossification centre forms
Secreted osteoid traps osteoblasts which become osteocytes
Trabecular matrix and periosteum form
Compact bone develops superficial to cancellous bone.
Crowded blood vessels condense into red bone marrow

Question 9

Where does endochondral ossification occur

Answer 9

Occurs at both the primary and secondary ossification centres

Question 10

What happens at primary ossification centres in endochondral ossification

Answer 10

Sites of pre-natal bone growth from the central part of the bone

Question 11

What happens at secondary ossification centres in endochondral ossification

Answer 11

Post-natal growth after the primary ossification center and long bones often have several (the physis)

Question 12

Describe the process of endochondral primary ossification

Answer 12

There is mesenchymal differentiation at the primary centre
The cartilage model of the future bony skeleton forms
Capillaries penetrate cartilage.
There is calcification at the primary ossification centre – spongy bone forms. Perichondrium transforms into periosteum
Cartilage and chondrocytes continue to grow at ends of the bone
Secondary ossification centres develop

Question 13

Describe the process of endochondral secondary ossification

Answer 13

Long bone lengthening

Question 14

Where does secondary endochondral ossification occur?

Answer 14

At the physis

Question 15

What happens on the epihyseal side of the physis?

Answer 15

Hyaline cartilage is active and dividing to form hyaline cartilage matrix

Question 16

What happens on the diaphyseal side of the physis?

Answer 16

Cartilage calcifies and dies and then replaced by bone

Question 17

How does elasticity differ between children and adult bone?

Answer 17

Children’s bone can bend and are more elastic than adult

This is due to increased density of haversian canals

Question 18

What is plastic deformity and why is it common in children?

Answer 18

When the bone bends before it breaks

It is common as children have more elastic bones

Question 19

What is Buckle fracture and why is it common in children?

Answer 19

It is an incomplete fracture (aka torus fracture) where one side of the bone buckles in on itself but the other side is fine. It is more common in children as their bones are more elastic

Question 20

What is greenstick fracture and why is it common in children?

Answer 20

When side of the bone bends and the other side snaps (like a twig), more common in children as they have more elastic bones

Question 21

When does bone growth in children stop?

Answer 21

When the physis close

Question 22

What factors affect when a child’s physes close?

Answer 22

Puberty
Menarche
Parental height

Question 23

When does an average girl’s and boy’s physis close?

Answer 23

Girls=15-16

Boys=18-19

Question 24

Why are physeal fractures more serious?

Answer 24

They can lead to growth arrest

Question 25

How does speed and remodelling in children's bones differ to adults?

Answer 25

It a lot faster and children can undergo a lot more deformity and angulation in comparison to adults

Question 26

What is developmental dysplasia of the hip? When does it occur?

Answer 26

Group of disorders of the neonatal hip where the head of the femur is unstable or incongruous in relation to the acetabulum, occurs in utero.

Question 27

What does normal hip development require that is disrupted in developmental dysplasia of the hip?

Answer 27

Concentric reduction and balanced forces through the hip

Question 28

What are the types of developmental dysplasia of the hip? What kind is the most common?

Answer 28

Dysplasia (this is the most common) Sublaxation Dislocation

Question 29

What are some risk factors for developmental dysplasia of the hip?

Answer 29

``` Female First born FH Breech Native americans/laplanders (due to habit of swaddling hip) Oligohydroamnios ```

Question 30

How is developmental dysplasia of the hip usually picked up?

Answer 30

Baby check (there is screening in the UK)

Question 31

How is developmental dysplasia of the hip treated?

Answer 31

Reducible hip and < 6months= pavlik harness | Failed harness or 6-18 months= MUA, closed hip reduction and spica

Question 32

What is club foot? When does it occur?

Answer 32

Congenital deformity of the foot that occurs in utero

Question 33

What population is club foot most common in?

Answer 33

Hawaiians

Question 34

What gender is club foot more common in?

Answer 34

Twice as common in men as in women

Question 35

Is club foot genetic?

Answer 35

Yes, 50% genetic

Question 36

What gene is involved in risk for club foot?

Answer 36

PITX1

Question 37

What pneumonic is used to identify club foot?

Answer 37

``` CAVE Cavus foot with high arch Adductus of foot Varus Eqinous ```

Question 38

How is club foot treated?

Answer 38

Ponseti method which is a primary series of casts to correct the deformity then surgery if needed later

Question 39

What is achondroplasia?

Answer 39

The most common skeletal dysplasia

Question 40

What is the pattern of inheritance for achondroplasia?

Answer 40

Autosomal dominant

Question 41

What gene is involved in achondroplasia?

Answer 41

G380 mutation of FGFR3

Question 42

Briefly describe the pathophysiology of achondroplasia

Answer 42

There is inhibition of chondrocyte proliferation in the proliferative zone of the physis This results in defects in endochondral bone formation

Question 43

What results from achondroplasia?

Answer 43

Rhizomelic dwarfism

Question 44

What are the characteristics of rhizomelic dwarfism in those with achondroplasia?

Answer 44

``` Humerus shorter than forearm Femur shorter than tibia Normal trunk Adult height of approx. 125cm Significant spinal issues ```

Question 45

What is osteogenesis imperfecta?

Answer 45

Brittle bone disease

Question 46

How is osteogenesis imperfecta inherited?

Answer 46

Autosomal dominant or recessive

Question 47

What type of collagen is reduced in osteogenesis imperfecta? Why?

Answer 47

Type 1 because there is decreased secretion and production of abnormal collagen

Question 48

What happens to osteoid production in osteogenesis imperfecta?

Answer 48

It is insufficient

Question 49

What are the effects on bone of osteogenesis imperfecta?

Answer 49

Fragility fractures Short stature Scoliosis

Question 50

What are non orthopaedic manifestations of osteogenesis imperfecta?

Answer 50

``` Heart problems Blue sclera Dentinogenesis imperfecta – brown soft teeth Wormian skull Hypermetabolism ```

Question 51

What pneumonic is used to describe fractures?

Answer 51

``` PAID Pattern Anatomy Intra/extra articular Displacement ```

Question 52

What are the different fracture patterns?

Answer 52

``` Transverse Oblique Spiral Comminuted Avulsion Torus Greenstick ```

Question 53

What are the different anatomy catagories when describing fractures?

Answer 53

Proximal, middle or distal 1/3rd of the bone

Question 54

What are the different fracture displacements?

Answer 54

Displaced Angular Shortened Rotated

Question 55

What classification method is used for physeal fracture?

Answer 55

Salter Harris

Question 56

What pneumonic is associated with the Salter Harris classfication and what does it stand for?

Answer 56

SALT Physeal Separation Fracture traverses physis and exits metaphysis (Above)= most common Fracture traverses physis and exits epiphysis (Lower) Fracture passes Through epiphysis, physis, metaphysis Crush injury to physis

Question 57

Going down the SALT pneumonic for Salter Harris classification what happens to risk of growth arrest?

Answer 57

Risk of growth arrest

Question 58

What happens if the whole physis is affected in a fracture?

Answer 58

There is limb length discrepancy

Question 59

What happens if only part of the physis is affected in a fracture?

Answer 59

Angulation as the non-affected side keeps growing

Question 60

What are the 2 aims in treating fracture affecting the physis?

Answer 60

Minimise angular deformity | Minimise limb length difference

Question 61

How can limb length be corrected in physeal fracture?

Answer 61

Shorten the long side | Lengthen the short side

Question 62

How can angular deformity be corrected in physeal fracture?

Answer 62

Stop growth on the unaffected side | Reform the bone (osteotomy)

Question 63

What pneumonic/phrase is used in fracture management?

Answer 63

Resuscitate Reduce Restrict Rehabilitate

Question 64

What common method of closed reduction is used for children?

Answer 64

Gallows traction which involves holding the skin so long bones of the lower limb can be reduced

Question 65

What is restriction in fracture management?

Answer 65

Maintainence of the fracture reduction

Question 66

What are external methods of fracture restriction?

Answer 66

Splints | Plaster

Question 67

What are internal methods of fracture restriction?

Answer 67

Plate and screws | Intra medullary device

Question 68

When operating on fracture in children what should be considered?

Answer 68

Ongoing growth at the physis | Metalwork that may need to be removed in the future

Question 69

What is a good rehabilitator for kids in relation to fractures?

Answer 69

Play

Question 70

What is the main differential in a limping child?

Answer 70

Septic arthritis

Question 71

How do children with septic arthritis usually present?

Answer 71

Previously well Gone off food in past 24 hrs Doesn’t want to put weight on their knee and hip

Question 72

Why must you exclude septic arthritis in a limping child?

Answer 72

Because its a medical emergency and can cause irreversible long-term problems in the joint

Question 73

What classification can be used to help score the probability of a child have septic arthritis?

Answer 73

Kocher’s classification

Question 74

What does Kocher’s classification for scoring probability of septic arthritis include?

Answer 74

Non-weight bearing ESR >40 WBC >12,000 Temperature >38

Question 75

What is transient synovitis?

Answer 75

An inflamed joint in response to a systemic illness

Question 76

How is transient synovitis treated?

Answer 76

Supportive treatment with antibiotics is the treatment

Question 77

What is Perthe's disease?

Answer 77

Idiopathic necrosis of the proximal femoral epiphysis

Question 78

How is Perthe's disease treated?

Answer 78

Supportive treatment

Question 79

What is SUFE?

Answer 79

Slipped upper femoral epiphysis where the proximal epiphysis slips in relation to the metaphysis

Question 80

Who does SUFE mainly affect?

Answer 80

Usually obese adolescent male

Question 81

What conditions is SUFE associated with?

Answer 81

Hypothyroidism and hypopituitrism

Question 82

How is SUFE treated?

Answer 82

Operative fixation with screw to prevent further slip and minimise long term growth problems

Question 83

What are the differentials in a limping child?

Answer 83

Septic arthritis Transient synovitis SUFE Perthe's disease