Musculoskeletal injury

Question 1

What are the two most common types of muscle injuries?

Answer 1

Contusions and strain-induced

Question 2

What causes contusions?

Answer 2

crush or compressive

Question 3

what causes strain-induced injuries?

Answer 3

tensile (stretching)

Question 4

what causes a laceration?

Answer 4

a cut

Question 5

what are the muscle groups commonly affected by muscle injuries?

Answer 5

hamstrings, adductors, quadriceps, and calf muscles

Question 6

which muscles are vulnerable to crush injuries?

Answer 6

the quadriceps

Question 7

what is the MOI of a crush injury?

Answer 7

a direct blow (blunt force)

Question 8

if the muscle is tensed with a crush injury is the force more superficial or deep?

Answer 8

superficial

Question 9

what is formed with a crush injury?

Answer 9

a hematoma

Question 10

could myositis ossificans occur with a crush injury?

Answer 10

yes

Question 11

what is myositis ossificans traumatica?

Answer 11

heterotypic bone formation (bone starts growing into the muscle)

Question 12

what is intramuscular myositis ossificans traumatica?

Answer 12

abnormal bone growth in one muscle

Question 13

what is intermuscular myositis ossificans traumatica?

Answer 13

abnormal bone growth in multiple muscles

Question 14

what determines if myositis ossificans traumatica is intramuscular or intermuscular?

Answer 14

how deep the force is

Question 15

could the abnormal bone growth go away with time?

Answer 15

yes

Question 16

what causes a mild (micro traumatic) strain-induced injury?

Answer 16

eccentric over-loading, or overexerting an untrained muscle

Question 17

what is mild strain-induced injuries?

Answer 17

soreness after new activity; minor muscle damage with delayed-onset muscle soreness (DOMS)

Question 18

what causes severe (macro traumatic) strain-induced injuries?

Answer 18

a rupture of muscle fibers, connective tissue, and blood vessels.
typically from overexerting the muscle quickly and stopping quickly

Question 19

where is severe strain-induced injuries the most common?

Answer 19

and the mho-tendinous junctions (where the tendon meshes with muscle)

Question 20

what happens when muscle is injured?

Answer 20

there is damage to connective and muscle tissue elements (typically at the myo-tendinous junction).
the damage to connective and muscle tissue elements is typically ultrastructural damage to the sarcomeres.

Question 21

what does muscle injury result in?

Answer 21

deficit in tension generating capabilities of muscle, strength loss and other signs and symptoms of acute injury.

Question 22

what are the three steps to muscle repair?

Answer 22

1. degeneration
2. regeneration
3. fibrosis

Question 23

what happens during degeneration?

Answer 23

a breakdown and removal of damaged cells and cellular debris

Question 24

what is the inflammatory response during the degeneration phase and when does it begin?

Answer 24

a system of vascular and cellular events. begins immediately after injury

Question 25

what happens during regeneration?

Answer 25

and activation of satellite cells, which signals myoblasts (muscle cell that wants to regenerate)

Question 26

what happens during the fibrosis stage?

Answer 26

activation of fibroblasts (tissue that scars)

Question 27

what tends to win in the competition between myoblasts and fibroblasts?

Answer 27

fibroblasts

Question 28

what are the two problems with fibrosis?

Answer 28

1. a lack of a signal to shut off or down-regulate fibrosis
2. over expression of collagen

Question 29

what propagates fibrosis?

Answer 29

TGF-beta1

Question 30

what is tendon

Answer 30

tight, parallel bundles of collagen that are “virtually dead during life”

Question 31

what do tendons do?

Answer 31

transmit forces of muscle to bone for joint movement and stability.

Question 32

are tendons highly vascularized and innervated?

Answer 32

no

Question 33

are tendons exposed to high mechanical load in tension?

Answer 33

yes

Question 34

what are tendon injury responses characterized by?

Answer 34

Tissue degenerative process.

Question 35

what is tendinopathy?

Answer 35

used to describe tendon-related symptoms that develop from overuse

Question 36

what is tendinosis?

Answer 36

Used to describe intra-tendinous degeneration

Question 37

Should you start with low load and high repetitions for tendons, or high load and low repetitions?

Answer 37

low load and high repetitions.

Question 38

is tendon responsive to eccentric loading exercises?

Answer 38

yes