Lecture 2 Flashcards
What are two competing events that occur during muscle strain healing?
Muscle Regeneration
Production of scar/fibrous tissue
What are common complications to Muscle strain healing?
Re-rupture from too early or overly vigorous mobilization
What is the fibril change when there is damage to C.T. and muscle fibril?
Break in to individual sarcomeric units
Disruption of mitochondria and sarcoplasmic reticulum
Interruption of sarcolemma
What do you want when you have damaged C.T. and muscle fibril with Satellite cells present?
Satellite cells are transformed into myoblastic cells
All satellite cells respond to a focal injury
What are the four stages of injury and repair?
Inflammatory reaction with hematoma formation
Macrophage inflitration
Fibroblastic and Collagenous proliferation
Function of the satellite cells
Which stages of injury and repair always occur and which stage does not?
Stages 1-3 always occur.
Stage 4 occurs when damage to the myofibril has occured
When will injury occur?
When the active tension in the muscle tendon unit exceeds the tension of the weakest structural element
Where are the most common injuries for muscle strain incidences?
Two joint muscles Hamstrings Gracillis Sartorius Rectus femoris Gastrocnemius
What percent of musculotendinous injuries are in the hamstring?
33%
For those with hamstring injuries, what percent are sprinters?
50%
For those with hamstring injuries, what percent are middle distance runners?
20%
When do hamstring injuries occur?
Early or Late stages of practice
What are the mechanism of injury for muscle strains?
Intrinsic force production
Extrinsic for production
Combination of both intrinsic and extrinsic force production
What are the 6 causative factors of muscle strains?
Inadequate flexibility Inadequate strength/endurance Dy-synergistic muscle contraction Insufficient warm-up Poor biomechanics/style Inadequate rehabilitation from previous injury
Physiologically, what occurs with inadequate flexibility?
Steeper stress strain curve (Poor dissipation of stress, viscoelastic response, and greater impact of force relaxation)
Change in length-Tension relationship
Clinically, what occurs with inadequate flexibility?
Higher incidence of microtrauma- (muscle strains, tendinitis)
Decreased Efficiency/effectiveness- (Movement dysfunction, Postural/functional imbalances
Physiologically, what occurs with inadequate strength/endurance?
Potentially weaker connective tissue
Neuromuscular changes inthe GTO and muscle spindle
Overload of normal tissue caused by abnormal biomechanics from fatigue.
Fatigue overload from repetitive stress
Clinically, what occurs with inadequate strength/endurance?
Inadequate muscular strength/endurance leading to macrotraumatic or microtraumatic injury
Ipsilateral or contralateral strength imbalance
Physiologically, what occurs with dys-synergic contraction?
Hybrid muscle with separate innervation (biceps, semitendinosis)
Fiber type and force development (hamstrings, rectus femoris, gastrocnemius/soleus)
Agonist-antagonist relationship
Clinically, what occurs with dys-synergic contraction?
Injury specific activities and positions (Hamstring deceleration v. acceleration)
Injury specific activities (Sprinters, higher angular velocity activities)
Over-strengthened (powering) antagonists
What is econcentric?
Where the distal part of the muscle in concentric while the proximal part is eccentric (or reversed)
Physiologically, what occurs with insufficient warm-up?
Lower intramuscular temperature
Decreased response of mechanical and physical properties of other tissues
Effect on muscle spindle and GTO interaction
Clinically, what occurs with insufficient warm-up?
Increased frequency of microtraumatic injury
Poorer performance
Increased incidence of dys-synergistic contractions
Physiologically, what occurs with inadequate rehabilitation?
Insufficient tissue maturation
Insufficient load tolerance
Sub-optimal condition and performance
Clinically, what occurs with inadequate rehabilitation?
Re-injury
Chronicity of injury
Other compensatory injuries
What are the 10 rehabilitative principles?
Prevention is easier than treatment
Intervention depends on healing stage
“Active rest” (guarded mobility) rather than mobility
Medications and modalities- important adjuncts
Develop a flexible tissue
Develop a strong tissue
“Said” principle is vital
Utilize the “progressive velocity flexibility program”
Pain is the guiding factor
No “quick fix” is possible
What is the SAID principle?
Specific
Adaptation to
Imposed
Demands
How can you prevent injury?
Education of patient regarding correct program
Proper utilization of warm-up and preventative flexibility program
Appropriate prophylaxis and self intervention in early phases
How is rest associated with rehabilitation?
Only used when absolutely necessary
“Active rest” used whenever possible rather than complete rest
Motion within the pain free range of motion is encouraged
What are three common modalities used in rehabilitation?
Cryotherapy (Early-limit inflammation, Late-prophylactic)
Thermotherapy (Late stage-improves circulation, healing, connective tissue mobility)
Electrical stimulation (Early-limit hemorrhage, Late- healing, strength, neuronal effect?)
What medications are used during rehabilitation?
Non steroidal anti inflammatory drugs (nsaids)
Phonophoresis
What are the positive effects of nsaids during rehabilitation?
Protogland inhibitory
What are the negative effects of nsaids during rehabilitation?
Systematic
Not local
Not Direct
What are the early and late stage reactions of phonophoresis?
Early-pulsed
Late-continuous
What are the percents of each phonophoresis medication?
Hydrocortisone-10%
Dexamethasone- 4%
Celestrone-6%
When exercising, what should be kept in mind in the early stages?
Flexibility- prevent scar contracture
Performance in the pain free ranges of motion
When exercising, what should be kept in mind in the late stages?
Strengthening and stretching- Develop flexible scar tissue
Long term process of developing strong tissue
Tolerance of high velocity deformation to prevent re-injury
For ballistic stretching what must you get past?
Neuromuscular component
What is stretching aided and hindered by?
Aided by influencing the gto
Hindered by facilitation of the muscle spindle
What does gto release cause in static stretching?
Release of tension
What are some advantages of static stretching?
Ability to control stretch without injury
Safer method to control stretch
Creep is influenced by this stretch
What does gto discharge cause in ballistic stretching
Sudden release of tension
What are the aspects of ballistic stretching?
poor ability to control stretch
Less control of stretch with greater degree of chance of injury
Force relaxation is influenced by this type of stretch
Often times athletic activities are what type of stretch?
Ballistic
