Orthopaedics Flashcards
How are bones in children different to adults?
- have growth plates
- more cancellous (spongy and highly vascular)
- more flexible but less strong - hence more prone to greenstick fractures
- heal more quickly with less long term deformity
What type of fractures are more likely in children?
- greenstick
- buckle (torus)
- salter harris (growth plate)
What is a greenstick fracture?
Where only one side of the bone breaks.
Name some different types of fractures?
- transverse
- oblique
- spiral
- segmental
- salter harris (growth plate)
- comminuted
- greenstick
- buckle (torus)
Describe the SALTR mnemonic for growth plate fractures
- Type 1 - Straight across
- Type 2 - Above
- Type 3 - beLow
- Type 4 - Through
- Type 5 - cRush
How should fractures be managed?
- achieve alignment then stability
- closed reduction (manipulation) - stabilise with external cast
- open reduction with surgery and fixation (e.g screws, nails)
Pain management - paracetamol or iBuprofen. Morphine if severe.
What is septic arthritis?
infection inside the joint
In which children is septic arthritis most common?
Under 4s
Or after operations - particularly joint replacements
How does septic arthritis present?
- hot, swollen, erythematous painful joint
- refusing to weight bear
- stiffness and reduced range of motion
- systemic features - fever, signs of sepsis
What bacteria commonly cause septic arthritis?
Staph aureus
Others include
- neisseria gonorrhoea in sexually active teens
- Group A strep (pyogenes)
- haem influenza
- E.coli
What are some differentials for septic arthritis?
- transient synovitis
- perthes disease
- slipper upper femoral epiphysis
- juvenile idiopathic arthritis
How is septic arthritis managed?
- have low threshold for investigating and treating as it can be subtle in young children.
- admit to hospital and involve ortho
- aspirate, microscopy and culture and sensitivities for diagnosis
- Empirical IV abx then specialise - for 3-6 wks
- may require surgical drainage and washout if severe
What is rickets?
Condition where there is defective bone mineralisation causing soft and deformed bones due to a deficiency in vitamin D or calcium.
How do we get vitamin D?
- produced in the body in response to sunlight
- through food - e.g. eggs, oily fish or fortified cereals
In which foods is calcium found?
- dairy - milk, cheese etc.
- some green veg
What is the equivalent to rickets in adults?
Osteomalacia
Who is more likely to have vitamin D insufficiency?
- darker skin
- avoiding sunlight
- malabsorption disorders - e.g. IBD
- chronic kidney disease ( as metabolises the vitamin D into its active form)
Why does a lack of Vitamin D affect bones?
- Vit D is essential for absorption of calcium and phosphate, which are required for the construction of bone.
- Low calcium then causes a secondary hyperparathyroidism.
- Hence more parathyroid hormone is produced. This stimulates reabsorption of calcium from the bones, worsening bone mineralisation.
What are some of the bone deformities seen in rickets?
- bowing of the legs (curve outwards)
- knock knees (legs curve inwards)
- rachitic rosary - ribs expand at the costochondral junctions
- delayed teeth
What are potential symptoms of rickets?
- lethargy
- bone pain
- swollen wrists
- bone deformity
- poor growth
- dental problems
- muscle weakness
- pathological or abnormal fractures
What investigations are done for rickets?
- blood test of vitamin D levels (<25nmol/L is deficiency)
- XRAY - may show osteopenia = more radiolucent bones
- serum calcium, phosphate, ALP or parathyroid hormone levels
- also do routine bloods to look for other pathologies / underlying causes
How is rickets managed?
- Breastfeeding women and children - take vitamin D supplements
- Treat with Vitamin D and calcium supplementation.
- Dose depends on age. Approx 6000IU per day.
What is osteosarcoma?
A type of bone cancer that most commonly affects young people between 10 and 20 years old.
In what bones is osteosarcoma most likely to occur?
- femur
- tibia
- humerus
How does osteosarcoma present?
- persistent bone pain - particularly worse at night
May have
- bone swelling
- a palpable mass
- restricted bone movements
How is osteosarcoma diagnosed?
- urgent direct access XRAY
- blood tests (show raised ALP)
To stage can do
- MRI
- CT
- Bone scan
- PET scan
- bone biopsy
What does osteosarcoma look for on XRAY?
- poorly defined region in bone
- destruction of normal bone and a ‘fluffy’ appearance
- may be associated soft tissue mass
How is osteosarcoma managed?
- surgical resection - often with limb amputation
- adjuvant chemotherapy
Close follow up with a MDT team.
What are the main complications of osteosarcoma?
- pathological bone fractures
- metastises
What is achondroplasia?
- The most common cause of disproportionate short stature - dwarfism.
- Skeletal dysplasia due to a mutation on the fibroblast growth factor receptor 3 gene (FGFR3) on chromosome 4.
- it can be sporadic mutation or is autosomal dominant (one abnormal and one normal chromosome - as homozygous is fatal in neonatal period)
How does the genetic mutation in the FGFR3 gene affect bone growth?
- abnormal function of epiphyseal plates, restricting bone growth in length. Also other dysplasia effects.
What is the average height of someone with achondroplasia?
4 feet
Describe the features of achondroplasia?
- short stature
- short limbs (particularly proximal - humerus and femur)
- normal trunk length
- short digits
- bow legs - genu varum
- disproportionate skull - large head
- flattened mid face and nasal bridge
- foramen magnum stenosis
What conditions is achondroplasia associated with?
- recurrent otitis media - due to cranial abnormalities
- kyphoscoliosis
- spinal stenosis
- obstructive sleep apnoea
- obesity (relative to height)
- foramen magnum stenosis can lead to cervical cord compression, hydrocephalus and can be fatal
How is achondroplasia managed?
- MDT support - to maximise functioning - e.g. physio, occupational therapists, ortho
- no cure
What is the life expectancy with achondroplasia?
Normal (if not affected by complications)
What is osteogenesis imperfecta?
- genetic condition - brittle bone disease
- prone to fractures
- range of genetic mutations that affect the formation of collagen (8 types that vary is severity)
How does osteogenesis imperfecta present?
- recurrent, inappropriate fractures
- hypermobility
- grey/blue sclera of the eyes
- triangular face/jaw
- short stature
- deafness from early adulthood
- dental problems - formation of teeth
- bone deformities - bowed legs and scoliosis
- joint and bone pain
How is osteogenesis imperfecta diagnosed?
- clinical diagnosis
- XRAYs can be useful for fractures and bone deformities
-genetic testing is possible but not done routinely
How is osteogenesis imperfecta managed?
- give bisphosphates and vit D supplements to help increase bone density
- managed by MDT
- physiotherapy
- occupational therapy
- ortho
etc.
What is osteomyelitis?
Infection in the bone or bone marrow. Can be acute or chronic.
What organism most commonly causes osteomyelitis?
Staphylococcus aureus (gram+)
How does someone get osteomyelitis?
Bacteria can enter directly - e.g. from an open fracture. Or have travelled via the blood after entering via another route - e.g. skin or gums
What are some risk factors for osteomyelitis?
- children <10
- open bone fracture
- orthopaedic surgery
- immunocompromised
- sickle cell anaemia
- HIV
- TB
How does osteomyelitis present?
Acute or chronic
- refusing to weight bear or use the limb
- pain
- swelling
- tenderness
- fever (chronic = low grade, acute = high)
- look out for signs it has spread to the joint causing septic arthritis
How is osteomyelitis investigated?
- Imaging - Xrays , MRI (best) or bone scan
- bloods = raised CRP and ESR and WCC
- blood culture
- bone marrow aspirate or bone biopsy with histology may be needed
How is osteomyelitis managed?
- prolonged antibiotic therapy
- may need surgical drainage and debridement of infected bone
What is another name for talipes?
club foot
What is talipes / club foot?
Where there is a fixed, abnormal ankle position at birth
What is talipes equinovarus?
When the ankle is in plantar flexion and supination
What is talipes calcaneovalgus?
When the ankle is in dorsiflexion and pronation
How is club foot treated?
- ‘ponseti method’ - foot is manipulated towards a normal position and a cast is applied to hold it in position immediately after birth. This is repeated multiple times until the foot is in the right position. Often also need a achilles tenotomy to relieve tension. Then use a brace to keep in place until the child is walking / approx 4 years old.
- surgery may be required if this fails
