Bone Pathology Flashcards
Define a fracture
A discontinuity in a bone resulting from mechanical forces which exceed the bones ability to withstand them
What are the causes of a fracture
Acute trauma - acute overwhelming force on normal bone
Fragility - mechanical forces that would not ordinarily result in fracture
Insufficiency - normal repetitive stress on abnormal bone
Stress - abnormal loading on normal bone
Pathological - bone may have a lesion that weakens it e.g bone density
What are the different fracture patterns
Transverse - straight across
Oblique - diagonal
Spiral - around bone
Comminuated - shattered bone
Avulsion - part of bone breaks off
Impacted -
Fissure - crack in bone
Greenstick - partial break
Closed vs open fracture
Closed - bone does not pierce skin
Open - bone pierces skin
Complete vs incomplete fracture
Complete - extends all the way across bone
Incomplete - doesn’t cross bone completely
Stable vs unstable fracture
Stable - treated with bracing and rest
Unstable - requires surgery to realign bones
How do children’s bones heal differently to adults
Children’s bones are always growing, more flexible, smaller, heal faster and are able to remodel or reshape
What are the main stages of bone healing and describe them
1 - haematoma formation (week 1), blood vessels damaged causing a haematoma (collection of blood clots) to form
2 - fibrocartilaginous callus formation (weeks 2-3), granulation tissue develops within haematoma, fibroblasts (produce collagen), chondroblasts (produce cartilage) and osteoblasts (produce bone cells) create the callus which connects the fracture ends
3 - callus ossification (1-4 months), cartilaginous callus undergoes endochondral ossification to form a hard, calcified callus
4 - bone remodelling (4-12 months), internal callus becomes stronger by osteoblasts and external callus is reduced by osteoclasts
What are the potential complications of a fracture
Shock, tetanus, wound infection, fat embolism, injury to vessels or nerves, DVT, adhesions
What is osteoporosis
Health condition that weakens bones making them fragile and more likely to break, develops slowly and often only diagnosed when a fall causes a bone to break
What is osteopenia
When a bone density scan shows you have lower bone density than average for your age but not low enough to be classed as osteoporosis
