8977 Lecture Notes - Lecture 3: Medial Collateral Ligament, Cartilage, Epiphyseal Plate
3 Jul 2018
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Pathology Tables
Ligament Injury
Role:
- Passive guidance of bones in joint motion (kinematics – glides, slides etc)
- Stability
oPrevents abnormal motion or dislocation
- Proprioception
oJoint position feedback – lig connected to brains
oInjury – osteoarthritis
Gross Appearance
- White
- Shiny – collagen makes them reflective
- Hard – collagen fibres packed together tightly
- Synovial covering tissue – potential vascular + neural supply – highly sensitive to pain
Structure + Function
- 65% water
- Dry weight
o75% - 85% - Type 1 collagen
o10% type 3
oproteoglycans
o1 – 2% elastin – allows recoil
o20% unknown
In the Ligament
- functional subunits – discrete bundles with individual roles
- indistinct from joint capsule – some blend with joint capsules – lead to areas injury
- shared roles
Differences between Ligaments – ALL LIGAMENTS ARE DIFFERENT
- anatomical variations
- different cell density
- different stiffness
- synovial sheaths and capsules
- proprioceptive functions
find more resources at oneclass.com
find more resources at oneclass.com
- different distributions of vascularity and nerve endings
Stress Strain Curve **exam q.
- how ligament behaves under stretch or load
- as load is applied = uncramping of fibres (toe or toe-in region, neutral zone)
- elastic zone = more load = more deformation = still able to recoil
- plastic zone = ^^ likelihood of microdamage, more permanent type of stretch
- Yeild = fibres break = failure zone
Damaged ligament = great displacement – curve flattens = low force lots of displacement
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Passive guidance of bones in joint motion (kinematics glides, slides etc) Proprioception: joint position feedback lig connected to brains, injury osteoarthritis. Hard collagen fibres packed together tightly. Synovial covering tissue potential vascular + neural supply highly sensitive to pain. Dry weight: 75% - 85% - type 1 collagen, 10% type 3, proteoglycans, 1 2% elastin allows recoil, 20% unknown. In the ligament functional subunits discrete bundles with individual roles indistinct from joint capsule some blend with joint capsules lead to areas injury shared roles. Differences between ligaments all ligaments are different anatomical variations different cell density different stiffness synovial sheaths and capsules proprioceptive functions different distributions of vascularity and nerve endings. Damaged ligament = great displacement curve flattens = low force lots of displacement. Pt can apply a lot more stress, more load, with similar movement. Age related differences adaptation: children softer and elastic. Often have insertional tears: skeletal maturity. Fibroblasts fibrocartilaginous sharpies fibres develop anchoring the ligaments into bone.
