Tissue Specific Healing

Question 1

Define contusion

Answer 1

muscle is subject to a sudden heavy compressive force

Question 2

Define strain

Answer 2

excessive tensile force leads on the muscle

Question 3

Describe skeletal muscle inflammatory phase

Answer 3

• hemostasis, hematoma, and inflammation occur within the first 24-48 hours
• necrosis of muscle tissue
• infiltration of leukocytes
• edema

Question 4

Describe skeletal muscle proliferation/repair phase

Answer 4

• matrix formation for fibroblastic function
• collagen formation from Type III to Type I
• excessive scar tissue creates a mechanical barrier for muscle fiber regrowth

Question 5

Describe muscle regeneration after transection (cut)

Answer 5

muscle fibers regenerate by growth from undamaged stumps or by growth of new, independent fibers

Question 6

Describe muscle regeneration of a contused or strained muscle

Answer 6

• capable of self repair
• process is slow and often incomplete
• loss of strength and high rate of re-injury

Question 7

Describe skeletal muscle remodeling

Answer 7

• 14 days post injury
• regenerating myofibers & maturation of new myofibers
• revascularization

Question 8

Describe skeletal muscle maturation

Answer 8

• extracellular matrix deposition
• scar tissue formation
• innervation of regenerated myofibers
• maturation of regenerated myofibers
• recovery of muscle functional capacity

Question 9

Functions of tendons & ligaments

Answer 9

• 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

Question 10

Describe tendons/ligaments inflammatory phase

Answer 10

• platelets begin clot formation
• phagocytic cells clear debris
• fibrin/fibronectin cross-linked collagen

Question 11

Describe tendons/ligaments proliferation phase

Answer 11

• occurs 2-3 weeks after injury
• fibroblasts secrete Type III collagen
• granulation tissue migrates & proliferates
• capillary sprouts blood vessels

Question 12

Describe tendons/ligaments maturation/remodeling phase

Answer 12

• 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

Question 13

What are the norms for health individuals during the tendon/ligament maturation/remodeling phase

Answer 13

• healing lasts 12-16 weeks to manage stressors
• 24 weeks strength is 40-60% of healthy tendon
• 40-50 weeks to gain normal strength

Question 14

What is the most common mechanism of injury for a ruptured tendon/ligament

Answer 14

oblique and rapid forces

Question 15

What are the different degrees of ligament sprains

Answer 15

Grade 1: stretching & small tears
Grade 2: large tear
Grade 3: complete tear

Question 16

Intraarticular ligaments properties

Answer 16

• 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

Question 17

Components of bone

Answer 17

• cortical 80% densely packed outer layer
• cancellous 20% spongy, containing trabecular providing structural support & strength

Question 18

What influences skeletal shape and mass of bone

Answer 18

• mechanical loading placed on it
• mineral homeostasis - hormonal factors

Question 19

Bone inflammatory phase

Answer 19

• bleeding occurs resulting in hematoma formation
• inflammatory cells arrive at the injured site
• accompanied by cellular proliferation

Question 20

Bone reparative phase

Answer 20

• 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

Question 21

Bone remodeling phase

Answer 21

• 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

Question 22

Important measures for inflammatory phase of soft tissues

Answer 22

• 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

Question 23

Stages of ROM for tendon or muscle ruptures

Answer 23

• 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

Question 24

When is returned to sports considered safe

Answer 24

• 80% return of strength compared to the noninvolved side

Question 25

When can a program be initiated

Answer 25

• a program can be initiated as soon as pain & swelling subside to recover range of motion, strength, and endurance