1b Children's Orthopaedics Flashcards
What is the area where long bone growth occurs post-natally called?
Physis
By what mechanism do bones develop in utero?
Flat bones form via intramembranous ossification
Long bones form via endochrondral ossification
How many physes do normal long bones have?
2 - one at the distal end and one at the proximal end
Which bones are formed through intramembranous ossification?
Flat bones of the skull, clavicle and mandible
Describe how the process of intramembranous ossification occurs?
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
What is endochondral ossification?
Development of long bone by replacing the hyaline cartilage precursor
What is endochondral ossification?
Development of long bone by replacing the hyaline cartilage precursor
What is the primary and secondary ossification center?
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)
Describe how primary endochrondral ossification occurs?
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.
In children, where does secondary ossification occur?
physis
What are the four differences between the adult and child skeleton?
- elasticity
- physis
- speed of healing
- remodelling
By the time the foetal skeleton is fully formed, cartilage remains at the joint surface. What is this cartilage known as?
Articular cartilage
During endochondral secondary ossification what happens at the epiphyseal side of the long bone?
Hyaline cartilage active and dividing to form hyaline cartilage matrix
During endochondral secondary ossification what happens at the diaphyseal side of the long bone?
Cartilage calcifies and dies and then replaced by bone.
What are the three types of deformities you can get oin childrens bones due to the fact they are more elastic?
- Buckle Fracture
- Plastic Deformity
- Greenstick fractures
Why are children’s bones most elastic than adult bones?
due to increased density of the haverisan canals as bones are more metabolicallt active
What is the mechanism for a Buckle fracture?
Buckle/Torus fracture - one side of bone bends raising a little buckle without breaking the other side of the bone.
What is a plastic deformity and how does it occur?
When childrens bones bend rather than snapping
What is the cause of bone growth stopping?
When the physis closes
When does the physis close in girls?
aged 15-16
when does the physis close in boys?
18-19
What scoring system is used to characterise physeal injuries?
Salter-harris
What can physeal injuries lead to?
Growth arrest -> deformity, as one side of the bone could keep growing and the other stops for example
What is the speed of healing dependant on in childrens bones?
The location and age of the patient
Which location in the body do the physis grow quickly?
Knee and extremities of the upper limb
What is the method used to describe paediatric fractures?
PAID
Pattern
Anatomy
Intra/extra articular
Displacement
What are some patterns of paediatric fractures?
Transverse
Oblique
Spiral
Comminuted
Avulsion
Plastic Deformity
greenstick
Torus Fracture
What causes fractures to occur in different patterns?
depends on the way the energy dissipates through the bone
How does displacement of the bone affect the ability to remodel?
Remodelling can occur when displacement is in the angle of function, but not when rotated
What is the Salter-Harris Classification of physeal injuries?
- physeal SEPARATION
- fracture ABOVE physis
- fracture LOWER than physis
- fracture THROUGH the physis = demoltion = arrest of growth
SALT
What occurs as a consequence of an injury affecting the whole physis?
Whole limb length discrepancy = different lengths
What occurs as a result of an injury affecting a part of the physis?
angulation as the non-affected side keeps growing
What are the aims when correcting physeal damage?
- minimise angular deformity
- minimise limb length difference4
How is limb length differences corrected?
Shorten the long side by prematurely fusing the physis
Lengthen the short side
How is angular deformity corrected?
Stop growth of unaffected side
reform the bone - osteotomy
What are the four R’s of paediatric fracture management?
Resusitate
Reduce
Restrict
Rehabillitate
What are the two forms of reduction?
Open and closed reduction
What does restriction involve in terms of fracture management?
Maintain fracture reduction and provide stability for healing by using forms of fixation so movement of the bones cannot occur
What are the fixation options in paediatric fractures?
- plasters and splits - remodelling and huge healing potential means that operative internal fixation can be avoided
What are the differentials for a limping child?
Septic Arthritis
Transient Synovitis
Perthes
SUFE - Slipped Upper Femoral Epiphysis
Why is diagnosis of septic arthritis important?
Is an ortho emergency
What is the treatment for septic arthritis?
Washing out the joint surgically
What are the things on the Kocher’s classification for septic arthritis diagnosis?
- Non-weight bearing
- ESR > 40
- WBC > 12000
- temperature > 38 (FEVER)
What is transient synovitis?
Inflammed joint in response to systemic illness
When is transient synovitis diagnosed?
Diagnosis of exclusion - only once septic arthritis can be excluded
What is the treatment for TS?
Supportive treatment with antibiotics - will usually go away in 2 weeks
What is Perthes Disease?
Idiopathic necrosis of the proximal femoral epiphysis
What age does Perthes disease usually occur in?
4-8 year olds
What differentiated Septic Arthritis and Perthes Disease?
Unlikely to see biochemical markers and fever in Perthes
What is the classic patient who might suffer from SUFE?
Obese adolescent male, 12-13 years of age
Which endocrine conditions of SUFE associated with?
Hypothyroidism and hypopituitarism
What is the treatment for SUFE?
Operative fixation with screw to prevent further slip and minimise long term growth problems
What is the investigation of choice for a SUFE?
X Ray
What is a Slipped Upper Femoral Epiphysis (SUFE)?
Proximal epiphysis slips in relation to the metaphysis
What is the treatment for Perthes disease?
Treatment is usually supportive in the first instance
Osteotomy - bone cut to shorten or lengthen it or change it’s alignment
-
What is the key diagnostic tool for Perthes disease?
Plain radiograph - X-ray
(Epiphyses on left side isn’t as well formed as on the right side)
Does Perthes Disease have a longer or shorter duration upon presentation than septic arthritis?
Longer
Limping child…what is the key differential?
SEPTIC ARTHRITIS
What is a great rehabilitator for paediatric fractures in younger children?
Playing
What are the 2 types of restriction?
External and Internal
What type of restriction is more often used in paediatric fractures and why?
External - great healing potential therefore no need for surgery
What is DDH?
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
What are the risk factors for DDH?
Female
First born
What is meant by DDH being a packaging disorder?
A ‘Packaging Disorder’ - occur during pregnancy when the foetus is squished so abnormal bending of the arms or legs
What is the spectrum of DDH?
Dysplasia
Subluxation
Dislocation
What is Oligohydramnios?
Too little amniotic fluid
How is DDH usually picked up?
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
-
What investigation is done in infants from in the age range 0 to 4 months to check for DDH?
Ultrasound - measures the acetabular dysplasia and position of the hip
How id DDH treated if less than 6 months old?
Pavlik harness
If The Pavlik Harness has failed as a DDH treatment, what is the next treatment option?
(Manipulation under Anaesthesia) MUA + closed reduction an Spica
What is CTE?
Congenital Talipes Equinovarus
What deformities occur in CTE? (CAVE)
C avus - high arch
A dductus of foot - pointing inwards
V arus
E quinous
Tight tendoachillies
What is the gold standard treatment in Club Foot (Congenital Talipes Equinovarus)
Ponseti Method
- First a series of casts to correct deformity
- Many require operative treatment
Soft tissue releases - Foot orthosis brace
- Some will require further operative intervention to correct final deformity.
What is the genetic inheritance pattern of Achondroplasia?
Autosomal dominant
What mutation causes Achondroplasia?
- G380 mutation ofFGFR3
- inhibition of chondrocyte proliferation in theproliferative zoneof thephysis
- results in defect in endochondral bone formation
What is Rhizomelic dwarfism?
Humerus shorter than forearm
Femur shorter than tibia
Normal trunk
Adult height of approx. 125cm
What is Osteogenesis Imperfecta?
Brittle Bone Disease
Which ECM protein is reduced in OI?
Collgen - type 1, due to decreased secretion and production of abnormal collagen
What are the effects of OI on the bones?
Fragility fractures
Short stature
Scoliosis
What are the non-orthopaedic manifestations of OI?
Heart
Blue Sclera
Dentinogenesis imperfecta – brown soft teeth
Wormian skull
Hypermetabolism
Why are children’s bones most elastic than adult bones?
due to increased density of the haverisan canals as bones are more metabolicallt active
By the time the foetal skeleton is fully formed, cartilage remains at the joint surface. What is this cartilage known as?
Articular cartilage
By the time the foetal skeleton is fully formed, cartilage remains at the joint surface. What is this cartilage known as?
Articular cartilage
