Musculoskeletal Growth and Repair Flashcards
Diaphysis
Shaft of the bone
Metaphysis
the flare at the end of the shaft
Epiphysis
Joint on the side of the physis
Medullary Canal
Central cavity of bone shafts where red bone marrow and yellow bone marrow is stored, hence, the medullary cavity is known as the marrow cavity
Cortical bone
Dense form of bone which is found in the diaphysis. Its function is to resist bending and torsion. It is laid down circumferentially and is less biologically active.
Cancellous Bone
This is trabecular or spongey bone which is found in the metaphysis. It absorbs compression, is the site of longitudinal growth and is very biologically active.
Define a fracture
A break in the structural continuity of bone
State the possible reasons as to why a fracture may occur
High energy transfer, repetitive stress, or low energy transfers in abnormal bones
State stage 1 of fractures
Inflammation
When does inflammation begin
Immediately after the fracture
What occurs during inflammation after a fracture
There is a haematoma and fibrin clots form. There is the accumulation of platelets, PMN’s, neutrophils, monocytes, macrophages and fibroblasts, mesenchymal and osteoprogenitor cells. All of this results in osteogenic induction off cells from muscle and soft tissue
What are mesenchymal and osteoprogenitor cells
Transformed endothelial cells from the medullary canal and or periosteum
Why does angiogenesis occur during the inflammation stage
Macrophages produce angiogenic factors under hypoxic conditions
What can increase the amount of blood loss in a fracture
NSAID’s, open fractures and extensive tissue damage
What is stage 2 of fracture repair
Soft callus
When does soft callus occur
When the pain and swelling subside and lasts until bony fragments are united by cartilage or fibrous tissue
What can be given to patients to help with initial healing of bones (inflammation)
Platelet concentrates including platelet-derived growth factor, vascular endothelial growth factor, TGF-B, insulin-like growth factor
State the different treatment methods used during soft callus stage
DMB (demineralised bone matrix), bone graft, bone substitutes, autogenous cancellous bone graft, or allograft bone
State stage three of fracture healing
Hard callus.
What is hard callus
This is the conversion of cartilage to woven bone. There is increasing rigidity and obvious callus.
State stage 4 of fracture healing
Bone remodelling, this is the conversion of woven bone to lamellar bone. The medullary canal is also reconstituted
Delayed union
The failure of the fracture to heal in the expected time
State the reasons why delayed union may occur
- High energy injury
- Distraction
- Instability
- Infection
- Steroids
- Immune Suppressants
- Smoking
- Warfarin
- NSAID
- Ciprofloxacin
Non-union
This is the failure of the fracture to heal completely
State the reasons in which non-union can occur
- Failure calcification fibrocartilage
- Instability – excessive osteoclasis
- Abundant callus formation
- Pain and tenderness
- Persistent fracture line
- Sclerosis
