Tissue Specific Healing Flashcards
Define contusion
muscle is subject to a sudden heavy compressive force
Define strain
excessive tensile force leads on the muscle
Describe skeletal muscle inflammatory phase
- hemostasis, hematoma, and inflammation occur within the first 24-48 hours
- necrosis of muscle tissue
- infiltration of leukocytes
- edema
Describe skeletal muscle proliferation/repair phase
- matrix formation for fibroblastic function
- collagen formation from Type III to Type I
- excessive scar tissue creates a mechanical barrier for muscle fiber regrowth
Describe muscle regeneration after transection (cut)
muscle fibers regenerate by growth from undamaged stumps or by growth of new, independent fibers
Describe muscle regeneration of a contused or strained muscle
- capable of self repair
- process is slow and often incomplete
- loss of strength and high rate of re-injury
Describe skeletal muscle remodeling
- 14 days post injury
- regenerating myofibers & maturation of new myofibers
- revascularization
Describe skeletal muscle maturation
- extracellular matrix deposition
- scar tissue formation
- innervation of regenerated myofibers
- maturation of regenerated myofibers
- recovery of muscle functional capacity
Functions of tendons & ligaments
- can sustain high unilateral tensile loads, transfer forces, & provide flexible support
- can respond to tensile & compressive forces and return to normal
- the thicker the tendon the greater tensile strength it has
Describe tendons/ligaments inflammatory phase
- platelets begin clot formation
- phagocytic cells clear debris
- fibrin/fibronectin cross-linked collagen
Describe tendons/ligaments proliferation phase
- occurs 2-3 weeks after injury
- fibroblasts secrete Type III collagen
- granulation tissue migrates & proliferates
- capillary sprouts blood vessels
Describe tendons/ligaments maturation/remodeling phase
- occurs ~3 weeks after initial injury
- Type III collagen is replaced with Type I collagen
- during early weeks (4-6 weeks) of remodeling the force required to rupture a repaired tendon can be as little as a muscle contraction
What are the norms for health individuals during the tendon/ligament maturation/remodeling phase
- healing lasts 12-16 weeks to manage stressors
- 24 weeks strength is 40-60% of healthy tendon
- 40-50 weeks to gain normal strength
What is the most common mechanism of injury for a ruptured tendon/ligament
oblique and rapid forces
What are the different degrees of ligament sprains
Grade 1: stretching & small tears
Grade 2: large tear
Grade 3: complete tear
Intraarticular ligaments properties
- poor healing response
- thin synovial sheath disrupts & blood dissipates preventing clot formation
-release of matrix proteins - months to years to synthesize & degrade collagen to remodel normal ligamentous properties to manage loads & stresses
Components of bone
- cortical 80% densely packed outer layer
- cancellous 20% spongy, containing trabecular providing structural support & strength
What influences skeletal shape and mass of bone
- mechanical loading placed on it
- mineral homeostasis - hormonal factors
Bone inflammatory phase
- bleeding occurs resulting in hematoma formation
- inflammatory cells arrive at the injured site
- accompanied by cellular proliferation
Bone reparative phase
- includes the formation of the soft callus - 2 weeks on x-rays
- repair lasts between 6-12 weeks
- osteoclast - bone macrophages
- osteoblasts - produce bone matrix
Bone remodeling phase
- begins once union has occurred - no movement
- ends when bone returns to normal
- disorganized woven bone is replaced with mature organized lamellar bone
- excessive boney callus is reabsorbed in response to stresses
Important measures for inflammatory phase of soft tissues
- after injury or surgery the soft tissue’s ability to hold sutures is at an all-time low
- protected rest is imperative during this stage
- gradually increasing tensile force that is slow enough to promote the next stages of healing
Stages of ROM for tendon or muscle ruptures
- controlled passive movement is allowed during the proliferative phase (5-28 days)
- around 4-8 weeks after injury active range of motion is initiated with controlled gentle movements
- resistance exercises is started at 8 weeks or later after repair
- at the end of 12 weeks with no complications, full force muscle contraction can be tolerated
When is returned to sports considered safe
- 80% return of strength compared to the noninvolved side
When can a program be initiated
- a program can be initiated as soon as pain & swelling subside to recover range of motion, strength, and endurance
