musculoskeletal injury Flashcards
what is an injury
Damage to the cellular structure of human tissue resulting from
the application of mechanical stress
what is mechanical stress
Amount of force acting within a structure”.
◼ Beneficial or injurious.
◼ 3 types of stress:
◆ Compression
◆ Tension
◆ Shear
what is compression stress
Particles pushed against each other.
what is tension stress
Particles pulled away from each other
what is shear stress
Particles slide relative to each other.
what are the 5 types of stress load
- Compression.
- Tension.
- Shearing.
- Bending.
- Torsion.
what is compression load
◼ Equal & opposite forces applied.
◼ Creates compression stress
within structure.
boxer nose fracture
what is tension load
◼ Equal & opposite forces pull away from each other.
◼ Creates tension stress within structure.
torn ligament
what is a shearing load
◼ Force applied parallel to structure surface.
◼ Creates shear stress within structure.
blister
what is a bending load
short side has a compression load
tension load on the long side
in the middle shearing load
what is Torsional Load
◼ Twisting about an axis.
◼ Induces shear, compression
& tension stresses.
ACL
what is a strain
Deformation of a body in response to stress
what are the 2 types of injuries
- Acute traumatic injury.
- Chronic overuse injury.
what causes an acute injury
◼ Results from a single episode of stress, exceeding a tissue’s tolerance.
◼ Creates macrotrauma.
what causes a chronic injury
◼ Results from repetitive application of stress at levels less than a tissue’s tolerance.
◼ Creates microtrauma.
how can chronic injuries cause tissue damage
◆ Magnitude of stresses.
◆ Total number of stress peaks.
◆ Interval between stresses (recovery period).
what is the Overuse Injury Theory
Increased / Altered activity
Increased training effort
Increased tissue stress
Stronger Tissue
Microscopic Tissue Damage
Tissue Remodeling
Remodeling Rate > Rate of damage
stronger tissue
examples of acute ligament injuries
sprain
ligament sprain
◼ Caused by:
Sudden over-stretch with joint in extreme position.
◼ Contact.
◼ Non-Contact.(ACL)
3 types of ligament sprains
grade 1:Microscopic Tearing
grade 2:Partial Disruption
grade 3:Complete Rupture
what causes muscle strain
Forceful “over-stretch”
Forceful eccentric contraction.
Combination.
acute skeletal injury
◼ A break in the structural continuity of bone.
◼ Caused by sudden and excessive force.
chronic skeletal injury
stress fracture
Microfractures (Stress Injury)
Small Cortical Fracture (Stress Fracture)
lowers tissue tolerance
examples of high risk stress fractures
◼ Stress fractures of femoral neck & middle
anterior tibia can progress to acute fracture.
tendon chronic injury
Tendinopathy - can lead to a rupture
◼ “Tennis Elbow”
◼ “Golfer’s elbow”
◼ “Jumper’s Knee”
what is pathophysiology
collagen degeneration and disorientation
