The Skeletal System Flashcards
Naming to bone in the skeleton
Skull
Orbit
Maxilla
Mandible
Clavicle
Sternum
Ribs
Humerus
Lumbar vertebra
Radius
Iliac crest of pelvis
Ulna
Sacrum
Metacarpal
Carpal
Phalanges
Femur
Patella
Fibula
Tibia
Tarsal
Metatarsals
Phalanges
Bone type
Long bone- length exceeds diameter eg femur or humerus
Short bones - length approximates to the diameter eg carpal bones
Flat bones - sandwich structure eg carnival bones and ribs
Irregular bones- vertebrae or mandible
Function of bone
Support
Leverage
Protection
Blood cell production (red marrow)
Storage of lipids (yellow marrow) and minerals eg calcium and phosphate
Bone anatomy
Adult
Diaphysis
Metaphysis
Child Diaphysis Metaphysis Physis (growth plate) Epiphysis
Bones in childhood
Key features
Growing- length, densisty, strength
Softer
Thinner
Lighter
More cartilage
Bone growth
There are two periods of rapid growth in children
The first two years of life
Puberty
One growth
Bone is a dynamic tissue that is built up and broken down in a continual process by the following cells
Osteoblasts - makes vine, lays down osteoid (soft bone) that then Beyoncé’s mineralised (hardened)
Osteocytes - mature osteoblasts that can repair and remodel bone
Osteoclasts - are multi- uncleared cells which resort bone during growth and healing
Bone mass
Bone mass refers to the weight of a bone
Peak bone mass is from 19-25
Final height is when you stop growing
Fracture zone is when you start to become weaker from 50 years to death
Osteoporosis
Bone mineral density or bone density: is a measurement of the weight and volume of a bone, which gives the density of a bone
Density = mass/ volume
Bone density is determined by a DEXA scab
(Dual energy X ray absorptiometry)
Low mineral density is know as osteoporosis And means that bones are prone to fracture and take longer to heal
Osteoporosis
Osteoporosis in children is usually seen in association with
Chronic medical conditions:
Cerebral palsy, juvenile idiopathic arthritis, osteogenesis imperfecta
Medications:
Anticonvulsant medication, corticosteroids and some cancer treatments
Bone growth determinants
Hormones that effect bone growth include
Growth hormone: drives the growth of bones until the adult size is reached
Thyroid hormone: required for skeletal development and peak bone mass
Testosterone: increases bone density
Oestrogen: are needed for maturation of the skeleton
PTH, vitamin D and calcitonin: all impact on Ca metabolism and bone growth
Bone growth determinants
Environmental and life style effects on bone growth include
Good nutrition including calcium, protein, vitamins and minerals are required to produce strong bone growth
Vitamin D is necessary for calcium uptake
Exercise helps increase bone density and effects bone shape
Long term disease can stunt growth (see previous slides)
Fractures in children
Fractures are normal part of growing up
Accidental fractures are common in children
- up to 66% of boys and around 40% of girls will sustain a fracture by their 15 th birthday
- 3.5% of children sustain a fracture each year in the UK
However they can also be indicative of abuse
Abusive fracture indicate a serious assault on a child
80% of abusive fractures are in children under 18 months
Fractures in children
Children have a greater proportion of cartilage in their bones than adults
A child bone structure is significantly more flexible than adults
Children bones are thinner and less dense than adult bones
This means that in the event of a fracture the bone will bend and splinter rather than snap
Childhood fractures and NAI
Non accidental injury’s should be consideration in all children with fractures, particularly so in children less than 18 months of age
Multiple fractures are more suspicious of abuse
The dating of fractures is an one act science
Hold hood fractures and NAI
Need to think of other children in the family. Studies suggest that up to 12% of household contacts aged less than two may have a positive skeletal survey, with twins being a particularly high risk
Fracture types
Closed (simple)
Open (compound)
Single- horizontal, oblique, spiral
Comminuted- multiple
Green stick - partial fracture
Torus- compression of cortex
Bowing- longitudinal force applied to bone
Presentation
Usually there is a clear history of the incident being witnessed
Sometimes there is no history as the event may not have been witnessed
Fractures in very young children may present with non-specific symptoms and my only be revealed by X-ray
Once the fracture is identified does the fracture match the history
Investigations
Plain X-ray
First line of investigation when there is a suspected accidental fracture
Fractures may not be obvious on X-ray immediately after the injury; they are easier to identify once the bone show some signs of healing
Investigations
Skeletal survey
considered when there is suspected non accidental injury
This is a series of plain X-rays of all the bones in the body
Repeat skeletal survey images 11 to 14 days later may show healing fractures not originally visible
Investigations
Radionuclides bone scan
Considered when there is suspected non accidental injury
This is a radionuclide bone scan uses a radioisotopes to identify a hot spot indicative of healing reaction at the site of a fracture
As skeletal surveys and bone scans can miss different fractures, consideration should be given to performing both in cases of NAI
Management
Pain relief - analgesia and immobilisation
Immobilisation- splinting, back slab, full plaster cast
Reduction - if bones are misaligned then they might be able to be put back in place
Surgery- if the fracture is severe, surgery may be needed to realign and fix the broken bones with insertion of metal wires, plates, screws or rods
Home healing
1 day - haematoma formation
3 days - inflammation
1 week - soft callus - granulation, matrix
3-6 weeks - callus - ossification, woven bone
8 weeks+ - re-modelling - absorb/deposit, strength, lamellar the bone
Complications
Healing in an abnormal position- children have a greater capacity than adults for remodelling
Infection- more likely in open fractures
Vascular and nerve injury - usually from the fracture, but also needs to be monitored for if a plaster has been applied
Bone necrosis- damage to nutrient artery and reduced blood supply
Delayed healing- usually secondary to other issues such as infection or pre-existing bone disease
Abnormal growth- stunted, extra or curving growth eg due to damaged epiphyseal plate, this is rare
Non union and fat embolism - both rare in children
Functional recovery
Bone fracture healing times vary considerably
The age and general health of the child
The bone affected as week as the type of bone
The type of fracture
Other aspects of the injury e.g infection
Fractures heal faster the younger the child - in a long bone repatriation return to full function may take 6 months
Summary
Fractures in children are common and mostly are accidental
Need to consider if the history matches the findings
If NAI is a suspected children social care will need to be involved
Childhood fractures and stages of bone healing are important knowledge to have when speaking to families when a child has a fracture
