Exam 2 - MSK 1B bone fx and healing Flashcards
Define fracture
Any defect in the continuity of a bone
What are the three etiology classes of fractures?
- Sudden traumatic fx
- Stress or fatigue fx
- Pathological fx
Describe Sudden Traumatic Fx, Stress/Fatigue Fx, and Pathological Fx
Sudden Traumatic=sudden episode of excessive force
Stress/Fatigue=Repetitive normal force. Doesn’t appear on xray until healing
Pathological Fx=Normal force on abnormal bone d/t bone failure
Definite Comminuted Fx, Pathological Fx, and Incomplete Fx
Communited=fx of 3+ fragments
Pathological=fx in area of preexisting bone disease
Incomplete=fx does not span across entire cross-section, no separate segments
Define Semental Fx and Butterfly Segment Fx
Segmental=middle fragment separated by proximal and distal segments
Butterfly Segment=Like Segmental but not through cross-section
Define Stress Fx and Avulsion Fx
Stress=fx caused by repeated loading of bone
Avulsion=tendon or ligament pulls off bone from insertion site
Define Displacement fx
Proximal and Distal segments not lining up
Define Angulation fx
Direction where the distal fracture “points”
What are the differences between Primary and Secondary Bone Healing
Primary=rigid bone stabilization takes longer, no calus formed
Secondary=less rigid bone stabilzation, early calus forms to provide stabilization
What are the three phases and time ranges of Secondary Bone Healing?
- Inflammatory Phase (1-2 weeks) “acute”
- Reparative Phase (Several months)
- Remodeling Phase (months to years)
What happens during the Inflammatory Phase of Secondary Bone Healing?
Increased blood flow forming hematoma. Osteoclasts remove damaged bone. Growth factors stimulate fibrobasts, osteoblasts, etc. Fx line on xray.
What happens during the Reparative Phase of Secondary Bone Healing?
Soft Callus forms and turns into Hard Callus by Osteoblasts mineralizing. Considered immature bone. Fx line starts to disappear.
What happens during the Remodeling Phase of Secondary Bone Healing?
Immature bone replaced by mature bone. Fx line disappears.
What are the two types of Primary Bone Healing? Describe.
- Gap Healing-Rigid fixation with small gaps and no movement at fx site
- Contact Healing-Rigid fixation with no gaps and no movement
Kid, Adolescent, and Adult fx healing times
Kids=4-6 weeks
Adolescents=4-8 weeks
Adults=10-18 weeks
Casts, Intramedullary rods/nails, Pins, wires, and screws are what kind of bone healing?
Secondary
Compression plate is what sort of bone healing? How does it differ from the other?
Primary. No weight bearing which takes longer. No periosteal callus formation.
What is different in External Fixation with “less rigid fixation” and “very rigid”?
Less rigid=Secondary healing. Callus forms.
Very rigid=Primary healing. No callus forms.
What is Wolff’s Law?
Mechanical stress leads to more bone density. Removal of mechanical stress decreased bone density.
Describe “delayed” or “non-union” healing complication
Segments don’t join back together. Might have a little bump.
Describe Avascular Necrosis and two most common sites
Cell death at site of fx. Scaphoid and Femoral Head.
Which part of the bone is called the “growth plate”?
Epiphyseal Plate
Define Type 1 Salter Harris
Disruption of the growth plate. Distraction or slip injury.