Week 1 Fractures Flashcards
Definition of a Fracture
A break on tissue continuity of a bone
Bone F# Epidemiology
Young Ages 15-24
Elderly > 65
What bones are commonly fractures (15-24)? How?
- Tibia, clavicle, lower humerus
- Traumatic
What bones are commonly fractured in elderly >65? How?
- Upper Femur, upper humerus, vertebra, pelvis
- Secondary to Osteoperosis
How are fractures classified?
According to Physiological and Pathological
Physiological Classification
- Fatigue: muscles are less able to absorb forces acting on bones
- Accident/injury
- Unusually strong muscle contractions
- Prolonged/repetitive physical stress fracture occurs as a result of excessive repetitive activity, resulting in inadequate healing times for osseous microtrauma
Pathological Fracture Definition:
-When a MODERATE/SMALL forces acts on a weakened of diseased bone causing a fracture
What causes a pathological fracture?
- Focal bone lesions: neoplasms; cysts; infections etc.
- Metabolic disorders: poor mineral absorption & hormonal changes decrease bone calcification causing weakened bones
- Disuse: atrophic muscles & osteopenia cause weakened bones
What are ways we classify fractures?
According to:
- Where the force causing the fracture acts
- The degree/extent of the fracture
- Whether the skin overlying it is broken
- The shape or appearance of the fracture line
Classification of Fractures BASED ON THE SITE OF THE FORCE?
- Direct: The bone breaks at the point of application of the force
- Indirect: The bone breaks at a site distant to the point of application of the force e.g. clavicular fractures following falls onto the palm of an outstretched arm
Compression F#:
Frequently seen with vertebral fractures. Bone has been compressed by other bones
Comminuted F#:
Bone broken, splintered or crushed into several fragments
Avulsion F#:
A fracture occurring when a joint capsule, ligament, tendon, or muscle is pulled from a bone, taking with it a fragment of the bone to which it was attached
Greenstick F#:
- A crack
- Bending of a bone with incomplete fracture
- Only affects one side of the periosteum
- Common in skull fractures or in young children when bones are pliable
Complete F#:
Bone is broken with disruption of both sides of the periosteum
What is the importance of fracture classification?
- Mechanism of fracture
- Seriousness of the fracture
- Stability of the fracture
- Time required for healing
- Type of treatment needed
- Prognosis
- Expected complications etc
Stages of healing of a fracture?
- Fracture occurs
- Haemorrhage
- Procallus Formation: Organsation of haematoma
- Fibrocartilaginous Callus Formation
- Bony Callus Formation
- Remodelling
Fracture healing timeline?
- Fracture occurs (day 1)
- Haemorrhage (2-5 days)
- Procallus formation; haematoma is organised (3-7 days)
- Fibrous cartilaginous callus formation (1-3 weeks)
- Bony Callus Formation (3-4 weeks, up to 2-5 months)
- Remodelling Stage (Months to years)
What is woven bone?
AKA non-lamellar bone: Immature type of bone tissue found in developing embryos. Collagen fibers of the woven bone matrix are arranged irregularly in the form of interlacing networks.
Osteoblasts make osteoid which matures, via calcification, into woven bone
Osteoid
- The unmineralized organic component of bone.
Stages of Healing
- Haemorrhage:
Takes place due to the highly vascular nature of bone tissue.
Events occurring in this stage:
•Intense inflammatory response
•Activation of local inflammatory cells
•Migration of inflammatory cells into the region
•Activation & proliferation of local CONNECTIVE TISSUE CELLS
What are the Local Connective Tissue Cells that proliferate following a fracture?
- Osteoblasts
- Osteogenic cells
- Fibroblasts
- Chondroblasts