Week 2 - Mechanisms of Sports Injuries Flashcards
Mechanisms?
how force is applied and resulting trauma
Biomechanics deviations
Stress
Tissue load (force)
Strain
Tissue deformation (change in shape) due to load
Stiffness?
Relationship b/w stress/ stress = Ability of tissue to resist load (stress/ strain) - SLOPE
Stress/ Strain Curve details?
Elasticity = ability for tissue to return to shape after deformation
Yield Point = elastic limit of tissue - permanent changes occur
Ultimate Strength Point = highest stress a tissue can withstand before failure
Occurrence of Injury?
Once there is mechanical failure and tissue can’t withstand stress and strain
2 Forms of Tissue Failure?
Load to Failure = Rupture/ # –> continuous force until break
Fatigue Failure = Subthreshold load repetition results in fatigue -> plastic region. No acute force - Chronic - Stress #.
Types of Load?
Compression
Tension
Shearing
Bending
Torsion
Models of Injury?
Acute vs Chronic
Different mechanism of time frames both relate to stress/ strain curve
Acute injury?
Load to failure
Immediate
One external load creates enough stress to exceed failure tolerance (yield point)
Chronic Injury?
Repeated load or constant load
Fatigue to Failure
dvlp over time
over use
Strain Injury?
Stretch/ rip/ tear in msc, tendon, or msctendon junction
Pain on active mvm (contraction)
Pain on active or passive stretch
Common during eccentric
Two joint mscs most susceptible
Edema is common
Can also be hematoma
Grading of Strains?
1 = some stretch/ tear. tender/ pain w/ active mvm, Full ROM
2 = more fibers stretched/ torn. Pain w/ active mvm. Swell, ecchymosis, decreased ROM
3 = complete rupture, significant decrease mvm, intense pain but then decreases. 6-8 weeks
Ecchymosis?
Bruise
Cramps?
involuntary msc contraction b/c lack of water / electrolytes
Msc Guarding
msc contraction in response to pain/ injury –> protect injured area
Spasm
involuntary contraction causes increased tension/ shortening of msc that interferes w/ voluntary mvm.
Clonic = involuntary contract and relax
Tonic = constant contract
DOMS?
12 hours after exercise
24-48 hours
resolves in 3-4 days
micro tears in msc
Tendinopathy?
Injury to tendon
- need to warm up to decrease pain but next day after activity pain increases
3 forms of Tendinopathy?
Progression from 1-3
2 and 3 have same treatment
1) Tendonitis = inflamed tendon - swell, pain, tender, warm, crepitus
2) Tendonosis = tendon breakdown w/ out inflammation.
Degeneration b/c of overuse
3) Tenosynovitis = inflammation of tendon/ synovial sheath (crepitus + increased friction against bone)
What type of injury is a Tendonopathy? Describe why.
Overuse injury
Tendons need 2-3 days to recover
- Mechanical loading causes collagen synthesis and degradation.
- Repetitive loading (w/in 1first 24 hrs) causes more degradation than synthesis
Synthesis lasts longer than degradation so you get a net synthesis (rebuild) unless overuse –> THERE IS A GRAPH for PROTEIN SYNTHESIS
Treatment of Tendonopathy
Don’t do nothing or just push through
Load management is essential
Pain should be at 3/10 during activity
Start w/ isometrics –> then eccentric –> progress to concentric –> then compressive (add load) –> then plyometric loading –> then plyometric w/ compression
Always consider the causes on injuries and determine if change is needed
Stress Shielding Theory?
Believes Eccentric mvm is best for tendon rehab
Mscs function as shock absorbers during eccentric contractions
–> Therefore, reduced absorption/ load on tendon
Myofascial Trigger Points?
- Hyper sensitive points within msc or fascia
- Often in posture mscs
- acute or repeated micro trauma
Latent TP = pain only w/ direct pressure (may limit ROM/ cause weakness)
Active TP = pain at rest (pressure causes jump sign). Referred pain
Myofascial Trigger Points?
Massage
TP release
Stretch
Correct msc imbalance
contusion rehab?
= a bruise
ecchymosis = change in skin color
Light stretching (decreases myositis ossficans = calcium deposits in msc)
No deep tissue massage
Synovial Joint Characteristics/ Components?
- Acrticular (hyaline) cartilage lines bones
- Joint capsule (inner surface = synovial membrane - high vascularized, produce synovial fluid - lube, absorb, nutrition)
Ligaments (main structure for joints) - can be part of capsule or separate
What is a sprain and grading?
Tensile injury to Ligs.
when stress causes a joint to move beyond normal ROM
G1 = some stretch/ separation of fibers, minimal instability, mild pain, localized swell, stiff
G2 = Tear/ separate fibers, moderate instable/ pain/ swell/ stiff.
G3 = Total tear, Instable. Severe pain then decreases, swell and stiff.
S&S for Sprain?
Joint Effusion (blood/ synovial fluid)
Heat
Ecchymosis
Tenderness on palpation
Swellin starts gradually (low BS)
Immediate pain (lots of nerves)
More pain w/ passive mvms
Healing abilities and rehab for sprains?
- Ligs. heal poorly (low blood supply)
- Rehab relies on strengthening/ training surrounding structures (mscs/ tendons).
- Can’t train a lig.
Dislocation?
Bone forced out of joint and stays out
- deformity/ asymmetry
- Relocatiing not in our scope
- splint in current condition
- send to hospital
Subluxation?
Bone forced out and back into joint
- pain and instability
- stretched/ torn ligs., nerves, mscs, joint capsule
Osteoarthritis?
Chronic
- degeneration of articular cartilage = changes in subchondral bone due to micro trauma
- Usually in weight-bearing joints
- S&S = stiff, swell, pain
- Previous trauma increases risk
- Cartilage doesn’t have blood supply = low healing
- No cure
Bursitis?
acute or chronic inflammation of bursa
Bursa = synovila fluid sack to decrease friction
Irritation results in increased fluid production causing pressure and pain
Bone Characteristics?
Support, protect, mvm, calcium storage, produce RBCs
Compact bone (outer core w/ blood/ lymphatic vessels + nerves)
Cancellous bone (porous, epiphysis)
Metaphysis = growth plate (cartilage - weaker)
Osteoclasts break down
Osteoblasts build new
Peak mass in 20s
2 Broad categories of Bone fractures(#)?
Simple/ closed = # under skin
Compound/ open = # through skin
Greenstick #
in not fully ossified bone (kids)
Linear #
in straight line parallel to shaft
Transverse #
perpendicular to shaft
Oblique #
Angled # (torsion/ bending)
Spiral #
Twisting
Impacted #
Compression of bone causes Telescoping
Avulsion #
Bone fragment attached to tendon or ligament
Comminuted #
3 or more # sites
Stress # causes?
Chronic
- msc overload on bone
- Improper distribution of stress by bone
- Repetitive stress
- Change in surfaces or foot wear (grass to floor)
- overtraining
- start training too fast
- R2P too soon
- Genetics
Bone absorption occurs faster than reformation
Stress # S&S?
Early Stage
- localized tender/ pain
Late Stage
- Pain w/ activity, constant pain, night pain, percussion test
Shin splints vs stress #?
Shin Splints = Medial Tibial Stress syndrome
- msc pulling away from bone
Osteochondrosis?
Chronic conditions in teens
- Degradation of bone ossification centres during rapid growth
- Unknown cause (maybe avascular necrosis)
Nerve Injuries?
Acute or Chronic
- Change in sensation (hypoesthesia or hyperesthesia)
- Numb or tingling
- Sharp or burning pain
- Regeneration is slow (3-4 mm/ day)
Neuropraxia?
Mild blunt force temporarily stops nerve conduction (funny bone)
Neuritis
Inflammation of the n. (sciatica)
