Fractures and Bone Healing Flashcards
What are pathological fractures?
Fractures that do not follow trauma.
What are possible complications of fractures of teh ribs?
Fractures of the ribs can do damage to internal structures such as the lung causing a puncture, pneumothorax or haemorrhage.
What are the different classifications of fractures according the their clinical presentation?
- Complete: fractured bone into two or more fragments (transverse, spiral, impacted, comminuted)
a. Risk of severing nerve and haematoma - Incomplete: bone incompletely divided (stress, compression, greenstick)
- Simple (closed): clean break, no penetration of overlying tissue structures
- Compound fracture (open): breaking through overlying skin
a. High risk of necrosis and infection
What is a complicated fracture?
A fracture is named as complicated when it involves adjacent structures such as vessels, nerves etc.
What are the different types of fractures?
- Transverse fracture: occurs when a perpendicular force is applied in the long axis of a bone.
- Spiral fracture: results from torsion forces inflicted over a long bone.
- Compression fracture: results from a force applied along the long axis of the bone.
- Angulation and displacement: of the fractured ends occurs when there is a combination of compression forces.
What are the possible complications following a fracture?
- Extensive muscle necrosis
- Haemorrhage following rupture of capillaries and larger vessels surrounding the damaged area
- Tearing of tendinous insertions and ligamentous attachments
- Nerve damage caused by stretching, direct tearing of the nerve, or compression by haemorrhage or oedema.
generally, how do bones heal?
Bone fractures heal by granulation tissue formation and fibrous repair followed by new bone formation in the fibrous granulation tissue.
What are the phases of fracture healing?
- Inflammatory phase (1-2 days)
a. Tissue destruction and haematoma formation
b. Inflammation and cellular proliferation - Reparative phase (1st week)
a. Callus formation: formed from cartilagineous (fibrocartilage) tissue.
b. Consolidation: substitution of cartilaginous to osseous tissue =transitional ‘woven’ bone - Remodelling phase (several weeks after)
a. Bone remodelling
b. Can even take up to years to finish
c. Lamellae develop and are arranged according to mechanical stress.
What is non-union?
- When a fracture does no heal
- Separation of the fragments
- Interposition by soft tissues between the fragments
- Excessive movement at the facture line
- Poor local blood supply
- Infection
- Formation of a pseudoarthrosis
What are factors affecting bone healing?
- Deficient or poor blood supply due to vascular pathologies
a. E.g. arteriosclerosis and thrombosis - Regional external vascular compression reducing tissue nutrition
- Nutritional deficiencies
a. Ca2+, phosphate, vitamin C, protein and trace elements - Metabolic disorders
a. Diabetes, hypothyroidism, osteoporosis - Infections
a. Chronic bacterial - Drugs
a. Corticosteroids, thyroid HRT, phenytoin, carbamazepine - Neoplasias
a. Mammary, pulmonary, prostatic
What are conditions that may present pathological fractures?
- Osteonecrosis
- Congenital bone disorders
- Osteoporosis
- Osteomalacia
- Paget’s disease of the bone
- Primary and secondary neoplasias
What is osteonecrosis?
This is a generic term for osseous necrosis following irreversible ischaemia
Legg-Calve-Perthes disease
- Osteonecrosis in the femoral head in children
- Unknown aetiogenesis
- Pathogenesis: stress fractures to necrotic bone lead to compaction over long term
- Joint malfunction and severe osteoarthritis
- Idiopathic osteonecrosis is the adult equivalent with similar development and clinical presentation.
- Presents clinically as joint malformation and severe osteoarthritis.
- Commonly occurs in 8-12 year older
Osteogenesis imperfecta
‘brittle bone disease’
• Congenital disorder
• Mainly as dominant presentations
• Mutations in genes coding for type I collagen synthesis
• Defective osteoid
• Varied clinical presentation (types 1, 2, 3 and 4)
• Can have cases of stillborn because the baby is crushed by contractions
