Lecture 6: injury classification and stages of healing Flashcards
1
Q
What is macrotrauma?
A
MSK trauma of large magnitude (strains, sprains, contusions)
2
Q
What is mictotrauma?
A
MSK trauma of small magnitude (stress fractures, overuse injuries)
3
Q
What are forms of MSK trauma?
A
Physical, chemical, thermal, metabolic, biological
4
Q
What are the directions of force?
A
- Tensile
- Compression
- Shear
- Torsion
- Bending
- Combined loading
5
Q
What are the 3 responses to force? Describe each one
A
- Elastic response - tolerable load
- load is removed and tissue returns to original shape - Yield load
- max amt of load before deformation - Failure
- does not return to normal shape (fractures, strains, sprains)
6
Q
What is the microfailure zone?
A
btwn elastic and plastic region, once load passes this zone and goes into plastic region, deformation occurs
7
Q
What is stress?
A
Force divided by area
8
Q
How does area affect magnitude of stress?
A
Force over large area has a smaller magnitude of stress
9
Q
What is acceptable strain tolerance of a tissue?
A
- load before failing
- deformation before failing
- energy stored before failing
10
Q
Stiffness of tissue: steeper slope =
A
greater stiffness
11
Q
Stiffness of tissue: greater stiffness=
A
less deformation
12
Q
On a strain vs stress graph, when does the elastic region end and become the plastic region?
A
The yield point
13
Q
What are the fibrous joints?
A
- synarthrosis
- sutures
- syndesmosis
- gomphosis
14
Q
what are the cartilaginous joints?
A
- synchondrosis
- symphyses
15
Q
What are the synovial joints?
A
- plane
- hinge
- pivot
- condyloid
- saddle
- ball-and-socket
16
Q
Synovial joints include
A
articular cartilage, synovial cavity, articular capsule, synovial fluid, and ligaments
17
Q
Describe connective tissue.
A
- joins structures together
- dense/loose
- regular/irregular fibers
- main components: collagen, elastin, reticulin (and ground substance)
18
Q
Describe collagen
A
- gives strength to tissue
- most numerous protein in the body
- bone 95% of extracellular matrix
- developed from fibroblasts
- crosslinks
19
Q
Describe elastin
A
- stretch property
- ability to return to original shape
- scarce in some structures (tendons and ligaments)
20
Q
describe ground substance
A
- protein chains that give substance to structure
- provide cement-like foundation (provide strength for collagen)
- hold water
21
Q
What is the cause of injury?
A
event altering tissue structure
22
Q
What are the effects of injury?
A
ability of tissues to carry out normal function/load
23
Q
What are closed soft tissue injuries (list them)
A
Muscle/tendon: strains, tendinopathy, contusions
Joint injury: sprains, dislocations/subluxations, articular cartilage damage, bursitis
24
Q
What is ecchymosis?
A
tissue discoloration if hemorrhage is superficial
25
What is hematoma?
swelling of clotted blood
26
Describe contusions
- direct compressive force from external blow
- ecchymosis
- hematoma
- complications: acute compartment syndrome, active bleeding, large hematomas
27
Classification for contusions: 1st degree
Damage: superficial tissues crushed
Weakness: mild, if any
Loss of function: mild
ROM: no restriction
28
Classification for contusions: 2nd degree
Damage: superficial and some deep tissues crushed
Weakness: mild to moderate
Loss of function: moderate
ROM: decreased
29
Classification for contusions: 3rd degree
Damage: deeper tissues crushed (fascia surrounding muscle may rupture, allowing swollen tissues to protrude)
Weakness: moderate to severe
Loss of function: severe
ROM: significantly decreased because of swelling
30
What are muscle strains
- injuries to muscle that cause varying degrees of tears to a muscle
- typically caused by stretch induced by a large contraction (eccentric contractions)
31
What are the S/S of muscle strains
- acute MOI - overstretch or overload
- pain located over injury site (commonly musculotendinous junction)
- discolorations (severe)
- muscle weakness and/or ROM limitations
32
Classification of Strains: 1st degree
Damage:
Weakness:
Muscle spasm:
Loss of function:
Swelling:
Palpable defect:
Pain on contraction:
Pain w/ stretching:
ROM:
Damage: few fibers of muscle are torn
Weakness: mild
Muscle spasm: mild
Loss of function: mild
Swelling: mild
Palpable defect: no
Pain on contraction: mild
Pain w/ stretching: yes
ROM: decreased
33
Classification of Strains: 2nd degree
Damage:
Weakness:
Muscle spasm:
Loss of function:
Swelling:
Palpable defect:
Pain on contraction:
Pain w/ stretching:
ROM:
Damage: nearly half of muscle fibers are torn
Weakness: moderate to severe
Muscle spasm: moderate to severe
Loss of function: moderate to severe
Swelling: moderate to severe
Palpable defect: no
Pain on contraction: moderate to severe
Pain w/ stretching: yes
ROM: decreased
34
Classification of Strains: 3rd degree
Damage:
Weakness:
Muscle spasm:
Loss of function:
Swelling:
Palpable defect:
Pain on contraction:
Pain w/ stretching:
ROM:
Damage: all muscle fibers torn (rupture)
Weakness: moderate to severe
Muscle spasm: moderate to severe
Loss of function: severe
Swelling: moderate to severe
Palpable defect: yes (if early)
Pain on contraction: none to mild
Pain w/ stretching: no
ROM: may increase or decrease depending on swelling
35
What are ligament sprains?
- acute traumatic injuries to ligaments
- placed in extreme ROM in which ligament supports
36
What are the S/S of ligament sprains?
- discomfort over ligament (point of tenderness)
- swelling
- loss of function
- increased laxity
- pain w/ stretching
- muscle weakness
- no contraction pain (theory no, real life yes!)
37
Classification of Spains: 1st degree
Damage:
Distraction w/ stress tests:
Weakness:
Muscle spasm:
Loss of function:
Swelling:
Pain on contraction:
Pain w/ stretching:
ROM:
Damage: few fibers are torn
Distraction w/ stress tests: <5mm distraction
Weakness: mild
Muscle spasm: none
Loss of function: mild
Swelling: mild
Pain on contraction: none
Pain w/ stretching: yes
ROM: decreased
38
Classification of Spains: 2nd degree
Damage:
Distraction w/ stress tests:
Weakness:
Muscle spasm:
Loss of function:
Swelling:
Pain on contraction:
Pain w/ stretching:
ROM:
Damage: nearly half of fibers are torn
Distraction w/ stress tests: 5-10mm distraction
Weakness: mild to moderate
Muscle spasm: none to minor
Loss of function: moderate to severe
Swelling: moderate
Pain on contraction: none
Pain w/ stretching: yes
ROM: decreased
39
Classification of Spains: 3rd degree
Damage:
Distraction w/ stress tests:
Weakness:
Muscle spasm:
Loss of function:
Swelling:
Pain on contraction:
Pain w/ stretching:
ROM:
Damage: all lig fibers torn (rupture)
Distraction w/ stress tests: >10mm distraction
Weakness: mild to moderate
Muscle spasm: none to minor
Loss of function: severe (instability)
Swelling: moderate to severe
Pain on contraction: none
Pain w/ stretching: no
ROM: may increase or decrease depending on swelling; dislocation or subluxation possible
40
What is a dislocation?
Bones are forced beyond normal limits (associated w/ damage to surrounding ligs and capsules, and possible muscle-tendon units)
41
What is a subluxation?
partial/incomplete dislocation
42
What is bursitis and when does it happen?
Irritation of bursa
- acute or chronic (single traumatic compression or repeated compressions)
43
S/S of Burstitis
- localized swelling (obvious in olecranon, prepatellar)
- point tender
- warm to touch
44
What is a common term for tendon pathology? How is it confirmed?
Tendinopathy (confirmed w/ histopathological examination)
45
What is tendinitis?
Tendons lack good blood supply, many have lack of direct inflammatory response (short-term)
46
What is tendinosis?
Degenerative changes result (chronic)
47
Tendinopath S/S
- chronic onset (MOI overuse or repetitive overstretching/overload)
- pain, swelling
- crepitus
- pain at extremes of motion (passive & active)
- pain increases during stretching and RROM
- strength decreases w/ pain
48
What is tenosynovitis? What are the symptoms if it's acute/chronic?
- Inflammation of synovial sheath surrounding a tendon (common in hands and feet)
- Acute: grating sound (crepitus) w/ mvmt, inflammation and swelling
- chronic: nodule formation in tendon sheath
- long term tendinopathy can lead to accumulation of mineral deposits in the bone (myositis ossificans)
49
What are the stages of overuse injuries?
Stage 1: pain after activity only
Stage 2: pain during activity that does not restrict performance
Stage 3: pain during activity that restricts performance
Stage 4: chronic, unremitting pain even at rest
50
What are intrinsic causes of overuse injuries?
- malalignment of limbs
- muscle imbalances (weaknesses, tightness)
51
What are extrinsic causes of overuse injuries?
- training errors (too fast too soon)
- faulty technique
- incorrect surfaces and equipment
- poor environmental conditions
52
What is osteoarthritis? What is the cause?
- degeneration of articular cartilage in a jnt
- caused by a combo of factors: stresses obtained during PA, jnt trauma, aging process
53
What are the S/S of osteoarthritis?
Pain, limited mvmt
54
What are muscle cramps?
Painful involuntary contractions of muscles (often exercise induced):
- Clonic: alternating contraction and relaxation
- Tonic: continued contraction
55
What are the causes of muscle cramps?
Exact causes unknown (biochemical imbalances, neuromuscular fatigue)
56
What are muscle spasms?
- Involuntary contraction of short duration caused by a reflex action
- Can be biochemically derived or initiated by a mechanical blow to a nerve or muscle
57
What are the 2 injury types?
Primary:
- caused by particular event
- external causes vs internal causes
Secondary:
- caused by complications after primary injury occurs
- hypoxia and ischemia
58
What are the phases of soft tissue healing?
- inflammatory
- proliferative
- maturation
59
What is the inflammatory phase of healing?
- Day 0-6
- greatest within first 24-72hrs
- inflammatory response is GOOD (need to control it)
- SHARP
60
What does SHARP stand for?
Swelling (tumor)
Heat (calor)
Altered function (function laesa)
Redness (rubor)
Pain (dolor)
61
Explain Part 1 of the inflammatory response.
- 1st goal: stop blood loss from wound
- local vasoconstriction (seconds to 10mins): large vessels constrict from signals from neurotransmitters
- reduction of blood vol = increased blood viscosity/resistance to the flow
- platelet rxn promotes clotting as cells combine together with fibrin: mechanical plug
62
Explain Part 2 of the inflammatory phase.
- vasodilation due to: histamine and bradykinin
- proteins are activated to promote activities for healing
- phagocytosis: attraction of macrophages + neutrophils
- release chemical mediators (bradykinin + histamine)
63
What does the release of Bradykinin and Histamine in Part 2 of the inflammatory phase do?
- inc. blood vessel wall permeability
- promotes vasodilation
- Pain!!
64
What are the vascular events of primary injury tissue damage?
- Vasoconstriction/platelet plug (sec-mins)
- vasodilation/inc. cell permeability (1hr)
- Hemorrhage
- edema: causes WBC infiltration
- ischemia/hypoxia (leads to secondary tissue damage)
- clotting/coagulation
65
What are the cellular events of (primary) tissue damage?
- vasoconstriction/platelet plug (sec-mins)
- mast cells release chemical mediators (histamine, bradykinin): causes vasodilation/inc cell permeability
- chemotaxis
- WBC infiltration
- phagocytosis (then secondary tissue damage)
66
What is the goal of proliferative phase of healing?
- Days 3-21
- repair and regeneration of injured tissues
67
What does proliferative phase entail?
Development of:
- new blood vessels
- fibrous tissue formation
- generation of new epithelial tissue
- wound contraction
Fibroblasts synthesize new type III collagen fibers
Angiogenesis: new vessel formation
68
What is the goal of the maturation phase?
Up to 1 year
- maturation of newly formed scar tissue
69
What is scar tissue?
- Fibrous, inelastic, and nonvascular (less strong/functional)
- less flexibility and decreased size of involved tissues
- excessive scar tissue: keloid tissue
70
What does maturation phase entail (apart from scar tissue)
- Type III becomes type I collagen
- Alignment of fibers along muscle fibers to regain mobility and strength
- tensile strength increase can continue up to 2 years later
71
What is the long-term impact of injuries?
- bad rehab that doesn't reorient collagen fibers: permanent of 30% compared to pre-injury strength
- muscle fibers are permanent cells and don't reproduce/proliferate
- ligs and tendons need to be in very close proximity to heal (if isolated (ACL), it has a poor chance of healing conservatively)
- tissue immobilization: atrophy, loss of strength, decreased healing
72
Inc immobilization time =
inc. atrophy
73
Describe nerve injuries
- do not heal as fast as soft tissues of bones
- heal at a rate of <1mm per day or 2.5mm per month
- most common: tensile and compression
