1b Children's Orthopaedics

Question 1

What is the area where long bone growth occurs post-natally called?

Answer 1

Physis

Question 2

By what mechanism do bones develop in utero?

Answer 2

Flat bones form via intramembranous ossification

Long bones form via endochrondral ossification

Question 3

How many physes do normal long bones have?

Answer 3

2 - one at the distal end and one at the proximal end

Question 4

Which bones are formed through intramembranous ossification?

Answer 4

Flat bones of the skull, clavicle and mandible

Question 5

Describe how the process of intramembranous ossification occurs?

Answer 5

A group of mesenchymal cells in the central ossification centres differentiate first into pre-osteoblasts and then into osteoblasts. - forms an OSSIFICATION CENTER

These cells synthesise and secreteosteoid and the osteoblasts further differentiate into osteocytes

These cells then collectively create the immature woven trabecular matrix and immature periosteum

Angiogenesis occurs and Blood vessels incorporated between the woven bonetrabeculae will form the future bone marrow.

Later, the woven bone is remodelled and is progressively replaced by mature lamellar bone

Question 6

What is endochondral ossification?

Answer 6

Development of long bone by replacing the hyaline cartilage precursor

Question 7

What is endochondral ossification?

Answer 7

Development of long bone by replacing the hyaline cartilage precursor

Question 8

What is the primary and secondary ossification center?

Answer 8

Primary = sites of pre natal bone growth via endochrondral ossification from the central part of the bone

Secondary = occurs post natally, after primary and at the physis’s (long bones often have more than one)

Question 9

Describe how primary endochrondral ossification occurs?

Answer 9

During endochondral ossification, the tissue that will become bone is firstly formed from cartilage. The first site of ossification occurs in the primary centre of ossification, which is in the middle of diaphysis of the bone - prenatal

a) Mesenchymal Differentiation at the primary centre

b) The cartilage model of the future bony skeleton forms

c) Capillaries penetrate cartilage. Calcification at the primary ossification centre – spongy bone forms. Perichondrium transforms into periosteum.

d) Cartilage and chondrocytes continue to grow at ends of the bone

e) Secondary ossification centres develop with its own blood vessel and calcification at the proximal and distal end – calcification of the matrix

f) Cartilage remains at epiphyseal (growth) plate and at joint surface as articular cartilage.

Question 10

In children, where does secondary ossification occur?

Answer 10

physis

Question 11

What are the four differences between the adult and child skeleton?

Answer 11

1. elasticity
2. physis
3. speed of healing
4. remodelling

Question 12

By the time the foetal skeleton is fully formed, cartilage remains at the joint surface. What is this cartilage known as?

Answer 12

Articular cartilage

Question 13

During endochondral secondary ossification what happens at the epiphyseal side of the long bone?

Answer 13

Hyaline cartilage active and dividing to form hyaline cartilage matrix

Question 14

During endochondral secondary ossification what happens at the diaphyseal side of the long bone?

Answer 14

Cartilage calcifies and dies and then replaced by bone.

Question 15

What are the three types of deformities you can get oin childrens bones due to the fact they are more elastic?

Answer 15

1. Buckle Fracture
2. Plastic Deformity
3. Greenstick fractures

Question 16

Why are children’s bones most elastic than adult bones?

Answer 16

due to increased density of the haverisan canals as bones are more metabolicallt active

Question 17

What is the mechanism for a Buckle fracture?

Answer 17

Buckle/Torus fracture - one side of bone bends raising a little buckle without breaking the other side of the bone.

Question 18

What is a plastic deformity and how does it occur?

Answer 18

When childrens bones bend rather than snapping

Question 19

What is the cause of bone growth stopping?

Answer 19

When the physis closes

Question 20

When does the physis close in girls?

Answer 20

aged 15-16

Question 21

when does the physis close in boys?

Answer 21

18-19

Question 22

What scoring system is used to characterise physeal injuries?

Answer 22

Salter-harris

Question 23

What can physeal injuries lead to?

Answer 23

Growth arrest -> deformity, as one side of the bone could keep growing and the other stops for example

Question 24

What is the speed of healing dependant on in childrens bones?

Answer 24

The location and age of the patient

Question 25

Which location in the body do the physis grow quickly?

Answer 25

Knee and extremities of the upper limb

Question 26

What is the method used to describe paediatric fractures?

Answer 26

PAID Pattern Anatomy Intra/extra articular Displacement

Question 27

What are some patterns of paediatric fractures?

Answer 27

Transverse Oblique Spiral Comminuted Avulsion Plastic Deformity greenstick Torus Fracture

Question 28

What causes fractures to occur in different patterns?

Answer 28

depends on the way the energy dissipates through the bone

Question 29

How does displacement of the bone affect the ability to remodel?

Answer 29

Remodelling can occur when displacement is in the angle of function, but not when rotated

Question 30

What is the Salter-Harris Classification of physeal injuries?

Answer 30

1. physeal SEPARATION 2. fracture ABOVE physis 3. fracture LOWER than physis 4. fracture THROUGH the physis = demoltion = arrest of growth SALT

Question 31

What occurs as a consequence of an injury affecting the whole physis?

Answer 31

Whole limb length discrepancy = different lengths

Question 32

What occurs as a result of an injury affecting a part of the physis?

Answer 32

angulation as the non-affected side keeps growing

Question 33

What are the aims when correcting physeal damage?

Answer 33

1. minimise angular deformity 2. minimise limb length difference4

Question 34

How is limb length differences corrected?

Answer 34

Shorten the long side by prematurely fusing the physis Lengthen the short side

Question 35

How is angular deformity corrected?

Answer 35

Stop growth of unaffected side reform the bone - osteotomy

Question 36

What are the four R's of paediatric fracture management?

Answer 36

Resusitate Reduce Restrict Rehabillitate

Question 37

What are the two forms of reduction?

Answer 37

Open and closed reduction

Question 38

What does restriction involve in terms of fracture management?

Answer 38

Maintain fracture reduction and provide stability for healing by using forms of fixation so movement of the bones cannot occur

Question 39

What are the fixation options in paediatric fractures?

Answer 39

1. plasters and splits - remodelling and huge healing potential means that operative internal fixation can be avoided

Question 40

What are the differentials for a limping child?

Answer 40

Septic Arthritis Transient Synovitis Perthes SUFE - Slipped Upper Femoral Epiphysis

Question 41

Why is diagnosis of septic arthritis important?

Answer 41

Is an ortho emergency

Question 42

What is the treatment for septic arthritis?

Answer 42

Washing out the joint surgically

Question 43

What are the things on the Kocher's classification for septic arthritis diagnosis?

Answer 43

1. Non-weight bearing 2. ESR > 40 3. WBC > 12000 4. temperature > 38 (FEVER)

Question 44

What is transient synovitis?

Answer 44

Inflammed joint in response to systemic illness

Question 45

When is transient synovitis diagnosed?

Answer 45

Diagnosis of exclusion - only once septic arthritis can be excluded

Question 46

What is the treatment for TS?

Answer 46

Supportive treatment with antibiotics - will usually go away in 2 weeks

Question 47

What is Perthes Disease?

Answer 47

Idiopathic necrosis of the proximal femoral epiphysis

Question 48

What age does Perthes disease usually occur in?

Answer 48

4-8 year olds

Question 49

What differentiated Septic Arthritis and Perthes Disease?

Answer 49

Unlikely to see biochemical markers and fever in Perthes

Question 50

What is the classic patient who might suffer from SUFE?

Answer 50

Obese adolescent male, 12-13 years of age

Question 51

Which endocrine conditions of SUFE associated with?

Answer 51

Hypothyroidism and hypopituitarism

Question 52

What is the treatment for SUFE?

Answer 52

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

Question 53

What is the investigation of choice for a SUFE?

Answer 53

X Ray

Question 54

What is a Slipped Upper Femoral Epiphysis (SUFE)?

Answer 54

Proximal epiphysis slips in relation to the metaphysis

Question 55

What is the treatment for Perthes disease?

Answer 55

Treatment is usually supportive in the first instance Osteotomy - bone cut to shorten or lengthen it or change it’s alignment -

Question 56

What is the key diagnostic tool for Perthes disease?

Answer 56

Plain radiograph - X-ray (Epiphyses on left side isn’t as well formed as on the right side)

Question 57

Does Perthes Disease have a longer or shorter duration upon presentation than septic arthritis?

Answer 57

Longer

Question 58

Limping child...what is the key differential?

Answer 58

SEPTIC ARTHRITIS

Question 59

What is a great rehabilitator for paediatric fractures in younger children?

Answer 59

Playing

Question 60

What are the 2 types of restriction?

Answer 60

External and Internal

Question 61

What type of restriction is more often used in paediatric fractures and why?

Answer 61

External - great healing potential therefore no need for surgery

Question 62

What is DDH?

Answer 62

Developmental Dysplasia of the Hip - group of disorders of the neonatal hip where the head of the femur is unstable or incongruous in relation to the acetabulum

Question 63

What are the risk factors for DDH?

Answer 63

Female First born

Question 64

What is meant by DDH being a packaging disorder?

Answer 64

A ‘Packaging Disorder’ - occur during pregnancy when the foetus is squished so abnormal bending of the arms or legs

Question 65

What is the spectrum of DDH?

Answer 65

Dysplasia Subluxation Dislocation

Question 66

What is Oligohydramnios?

Answer 66

Too little amniotic fluid

Question 67

How is DDH usually picked up?

Answer 67

**Baby check** → screening in the UK Range of motion of hip usually limited in **hip abduction**; leg length In those 3 months or older Barlow and Ortalani are non-sensitive -

Question 68

What investigation is done in infants from in the age range 0 to 4 months to check for DDH?

Answer 68

Ultrasound - measures the acetabular dysplasia and position of the hip

Question 69

How id DDH treated if less than 6 months old?

Answer 69

Pavlik harness

Question 70

If The Pavlik Harness has failed as a DDH treatment, what is the next treatment option?

Answer 70

(Manipulation under Anaesthesia) MUA + closed reduction an Spica

Question 71

What is CTE?

Answer 71

Congenital Talipes Equinovarus

Question 72

What deformities occur in CTE? (CAVE)

Answer 72

C avus - high arch A dductus of foot - pointing inwards V arus E quinous Tight tendoachillies

Question 73

What is the gold standard treatment in Club Foot (Congenital Talipes Equinovarus)

Answer 73

Ponseti Method 1. First a series of casts to correct deformity 2. Many require operative treatment Soft tissue releases 3. Foot orthosis brace 4. Some will require further operative intervention to correct final deformity.

Question 74

What is the genetic inheritance pattern of Achondroplasia?

Answer 74

Autosomal dominant

Question 75

What mutation causes Achondroplasia?

Answer 75

- G380 mutation of FGFR3 - inhibition of chondrocyte proliferation in the proliferative zone of the physis - results in defect in endochondral bone formation

Question 76

What is Rhizomelic dwarfism?

Answer 76

Humerus shorter than forearm Femur shorter than tibia Normal trunk Adult height of approx. 125cm

Question 77

What is Osteogenesis Imperfecta?

Answer 77

Brittle Bone Disease

Question 78

Which ECM protein is reduced in OI?

Answer 78

Collgen - type 1, due to decreased secretion and production of abnormal collagen

Question 79

What are the effects of OI on the bones?

Answer 79

Fragility fractures Short stature Scoliosis

Question 80

What are the non-orthopaedic manifestations of OI?

Answer 80

Heart Blue Sclera Dentinogenesis imperfecta – brown soft teeth Wormian skull Hypermetabolism

Question 81

Why are children's bones most elastic than adult bones?

Answer 81

due to increased density of the haverisan canals as bones are more metabolicallt active

Question 82

By the time the foetal skeleton is fully formed, cartilage remains at the joint surface. What is this cartilage known as?

Answer 82

Articular cartilage

Question 83

By the time the foetal skeleton is fully formed, cartilage remains at the joint surface. What is this cartilage known as?

Answer 83

Articular cartilage