Mechanisms of injury Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is a muscle strain?

A

Overstretching of a muscle in which muscle fibres tear - usually near muscle tendon junction
Highest in eccentric contraction where under linear contraction force but lengthening

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What muscles often experience muscle strain?

A

Hamstring
Quadriceps
Hip flexors
Hip adductors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the grading of muscle strains?

A

Grade 1- some fibres involved
Grade 2 - signficant number of fibres invovled
Grade 3 - complete tear or rupture- usually in already tendinopathic sufferers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Whats the challenge about muscle strains?

A

High incidence rate
High re injury rate
Slow healing
Persistent symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Of the hamstrings which is most at risk and why?

A

Biceps femoris
Thought to occur in terminal phase of gait cycle - 2nd half hamstring are active and lengthened - reaches 110% of its length in upright position.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What was loughborough’s research in relation to Hamstring strains?

A

Aponeurosis size - disproportionately small biceps femoris long head aponeurosis suggested as a risk factor as the mechanical strain is concentrated to a small area
Found - high variation in aponeurosis size but not related to muscle size and knee flexor strength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the signs and symptoms of a hamstring strain?

A

Usually occur during sprinting - limb suddenly after a brief bout of explosive sprinting and would be forced to stop and fall to ground
localised stfiffness, tightness, discolouration, swelling, redness and bruising
May have a stiff leg gait as cannot use hamstring to initiate movement

Broad discoloration may indicate high grade myotendionous injury or avulsion #

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Explain the examination of a suspected hamstring strain

A

Palpate to check for muscle belly rupture - precise location may be hard to identify as deep
- Hurdle test
- Bent knee stretch test
Increased posterior thigh pain with extension indicates possible hamstring strain or tendinopathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What imaging may be used in suspected hamstring strains?

A

XR - negative results unless ischial tuberosity avulsion #
Dynamic ultrasonography - identify fluid collections - oedema and internal bleeding
MRI/ CT- precisely define injury location, degrees of damage, number of involved tendons, extent of retraction and chronicity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How can we assess knee strength?

A

Maximal torques generated by hamstrings and quadriceps and ratio is isokinetic dynamometer test - flexion and extension speed fixed- resistant depends on torque participant can generate leading to no harm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the different types of strength ratio hamstring to quads?

A
  • Conventional H:Q ratio - concentric to concentric
  • Functional H:Q ratio - eccentric to concentric
  • Concentric - Eccentric
  • Eccentric - Eccentric
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which ratio is usually used and why?

A

Functional H:Q - Hamstring usually lengthened when working

Should be at least 60% - more preferable to at least 75%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the issue with resting time from a muscle strain?

A

Too long hamstring would shrink and scar tissue form around the tear
Too little time risks reinjury

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Explain the management of a total hamstring tear

A

Surgical repair and braced with a hip orthosis in 30-40 degrees of flexion to limit stress to surgical site
Followed by rehab
Will need DVT prevention

Weight bearing with crutches > RoM development > isotonic exercise > dynamic hip training / isometric stretching > sports specific > full isotonic evaluation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Post a complete hamstring tear when can people return to sport?

A

When injured side is 80% strength of non operative leg

6-10 months

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What exercises are recommended by the NHS for hamstring strains?

A
Hamstring stretch 
Buttock stretch
Supine Walk out bridge
Supine single limb chair bridge exercise
single limb balance windmill touches with dumbbells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Explain the principles of the Nordic hamstring exercise

A

Partner exercise - leaning forward with someone resting on ankles. Asked to use their arms to buffer the fall and let their chest touch the surface and immediately push up to minimise concentric phase.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the advantages of the Nordic hamstring exercise ?

A

Can be done anywhere
Can be done entire team at once
Reduced injury risk- more effective

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

In the meta-analysis what were identified as the RFs - Hamstring strains?

A

Older age, previous injury of hamstring strain and increased quadriceps peak torque.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Explain model based image matching in relation to ACLs and its findings?

A

Excessive secondary movement - rotation and tertiary joint motion - AB and AD duction within 40ms of footstrike

  1. Abduction neutral at strike and then increased 10-13 degrees at 40ms
  2. External rotation of 5 degrees at footstrike and internally rotated to 8 degrees at 40ms
  3. knee externally rotated again 17 degrees afterwards
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Explain the theory about subluxation - cause or effect?

A
  1. valgus strain on MCL and lateral meniscus
    2, Compression and quadriceps contraction - posteriort translation of lateral femoral condyle and rupture of ACL at 40ms
  2. Without ACL- medial femoral condyle translated posteriorly–> tibial external rotation.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Explain the relationship between hamstrings, quadriceps and the strain on the ACL

A

Movement of the knee through a flexed to extended position - passively or actively increases ACL strain
When knee is almost fully extended strain on the ACL is greatest.
- At this orientation - isolated quadricep contraction increases strain
- Isolated hamstring contraction neither increases or decreased strain

Quadriceps contracting and hamstrings not - ACL is experiencing highest strain making it vunerable to injury

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Explain the principles behind an ACL repair

A

Injured ACL is removed
Drill holes in femur and tibia
Pass graft through the tunnels
Fix graft with screws

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Explain the double bundle and its repair technique

A

Anteriomedial bundle - translational,
Posteriomedial bundle - rotational

Can use a hamstring graft for repair
Double bundle repair can be done arthroscopically leaving very little scars.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Explain the difference between stability and laxity

How can each be tested?

A

Stability involves the contribution from muscles
Laxity - just testing the function of the ligaments

  • can be rotational or linear

Laxity can be tested using Arthrometer KT100- given a certain fixed amount of stress and then measure the displacement - higher displacement higher laxity
Stability can be tested using a dynamic functional test- good for gross evaluation but not for in vivo motions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How is the BPB graft obtained and what are the potiental consequences of this?

A

Open knee surgery - wound at anterior knee may cause loss of sensation numbness or discomfort in knealing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the methods that can be employed to help healing of a hamstring graft?

A
Bone morphogenic proteins 
Mesechymal stem cells
Calcuim phosphate cement 
Low intensity pulsed ultrasound
Shock wave therapy
US guided shock wave therapy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the main mechanism for ACL injury and what is injured in this?
How does this vary from the unhappy triad?

A

Knee in toe out
MCL, ACL and lateral meniscus

~Unhappy triad is medial meniscus and ligament and ACL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What percent of ankle sprains are each type and what is injured in each?

A
  • Lateral (85%) - Anterior talofibular ligament, posterior talofibular ligament and calofibular ligament
  • Medial (5%) - Deltoid ligament
  • High ankle sprain (10%) - interosseus membrane and sydesmotic ligament.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the issue with high ankle sprains?

A

Rarely diagnosed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How are each of the ankle sprains caused?

A

Lateral - inversion and supination
Medial sprain - eversion and pronation
High ankle sprain - Dorsiflexion and inversion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What muscles should aim to be strengthened during ankle sprain rehab?

A

Fibularis brevis and longus - main evertors of the ankle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the grading for ankle sprains?

A

Anatomical - based on the ligaments involved

1) AFTL only
2) AFTL and PFTL
3) AFTL, PFTL and CFL

Severity

  1. Mild/ partially stretched
  2. Partial tear
  3. Completely torn
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Why are eversion sprains more rare?

A

Fibular extends down to lower position in the form of the lateral malleolus providing an actual block

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is used to decide when to XR a ankle or foot?

What is good about these?

A

Ottowa Ankle/foot rules

They have a high sensitivity and good specificity - sensitivity means few false negatives - picks up most #s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is important to remember about the diagnosis of ankle sprains?

A

Cannot give a specific diagnosis for 5 days post injury

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are the tests done during examination of the ankle?

A
  • Anterior draw test - anterior translocation indicates instability
  • Talar tilt test - tests CFL - feel for separation between talus and tibia
    > foot must be neutral as otherwise tests the AFTL

High ankle sprains

  • Squeeze test
  • Crossed Leg test
38
Q

What is the management for a high ankle sprain and why?

A

Walker boot - compression holds the ankle in place and prevents any further stress on the interosseous membrane and syndesmotic ligament

39
Q

Why must we never use complete immobilisation in ankle sprain?

A

stiffness , atrophy and increased proprioception

40
Q

What are the two aietologies of lateral ankle sprains??

A
  • Delayed peroneal reaction - occurs at 40ms - peroneal muscles at lateral shank function to initiate ankle pronation which opposes supination- human reaction not fast enough to accomodate sudden explosive motions resulting in inversion sprains
  • Incorrect landing- supination and platarflexed - increased supination leads to medially deviated vertical ground reaction force which doesnt pass through the joint center and twisting torque is applied
41
Q

What are the chronic symptoms of ankle sprain?

A

Persistent synovititis, ankle striffness, swelling, pain, muscle weakness and giving way
1-4 sprains –> pain
5+ –> instability

42
Q

What are the two types of instability found at the ankle?

A

Mechanical - laxity of the ligaments
Functional - Abnormal function with recurrent episodes of giving way

Mechanical can lead to functional but functional may exist without mechanical.

43
Q

What are the general methods for prophylaxis of ankle sprains?

A
Prophylactic devices including strapping
Functional training 
Technique training 
Change of game rules 
Education
44
Q

Explain the intelligent anti-sprain system

A

Gyroscope heel monitor ankle twisting motions - causes electrical stimulation of the peroneal muscles at threshold- gives mechanical support from own muscles when needed - allow agile ankle for best sports performance.

45
Q

What are the issues of Nordic hamstring exercises?

A

As strength increases two or even three players might be required

Slow increase in repetitions and load was designed to minimise muscle soreness

46
Q

What were some of the issues with the nordic hamstring exercise study?

A

Limited results and purposes of the study due to being professional athletes - limited time and effort for testing and had to prioritize tests thought to be most relevant from injury prevention.

47
Q

What is the definition of tendinopathy?

A

overuse tendon injury occuring in loading tendons
resulting in pain, decreased exercise tolerance and decreased function.
Characteristic changes in tendon structure –> less capable of sustaining repeated tensile load
common to occur at attachment to bone- pathology induces a cell matrix change
- Variable recovery

48
Q

Explain the stages of tendinopathy

A
Stress Shielded 
Normal --> adapted tendon
Reactive tendinopathy 
Tendon disrepair 
Degenerative tendinopathy
49
Q

What are the assumed pathologies behind tendinopathy?

A

Mucoid, hyaline and hypoxia

50
Q

Give some of the features of reactive tendinopathy?

A

Homogenous thickening - fusiform manner of swelling
thicken to increase CSA to decrease stress and increase stiffness- increased proteoglycans and H20 content
No change in neurovaascular structures
Collagen intact
acutely overloaded tendon - more common in young

51
Q

Give some of the features of tendon dysrepair

A

Attempted healing - greater matrix breakdown- increased protein production resulting in separation of collagen
Increased vascularity and neuronal growth
Pain associated with vessels and neural centralization
Focal areas of hypoechogenicity - increased vascularisation on doppler

52
Q

Give the features of degenerative tendinopathy

A

LITTLE REVERSIBILITY
Focal changes - one or more nodular area with or without general thickening
Areas of increased cellularity and large areas of matrix filled with vessels, breakdown products and little collagen

US- hypoechogenic regions with few reflections from collagen
Numerous and large vessels on doppler

Sources of pain - hypoxia, neural and centralization

53
Q

What are the treatments for early tendinopathies?

A

Physical treatments- reduce loading

Pharmacokinetics - corticosteriods and NSAIDs

54
Q

What are the treatments for late tendinopathies?

A

Physical treatment - Friction therapy, USS, surgery and extra corpeal shock wave therapy
Pharmacotherapy - Prolotherapy and sclerosing therapy and GTN

55
Q

Explain what is meant by a ligament being visoelestic

A

Like a spring and a piece of grass
Stretch when under tension and return to original shape once tension is removed - cannot if past certain point or stretched for too long

if strained slowly they are lengthened - rapidly with snap

56
Q

What are the signs and symptoms of a tendinopathy?

A

Seemingly insidious onset of pain, well localised pain, pain on waking or starting activity that eases with movement, pain on direct palpation

57
Q

What are the risk factors for tendinopathy?

A

Intrinsic - gait, heavy hit strike, double heel lift, age BMI, previous injury
Extrinsic - fluroquinolones, steriods, footwear and exercise type.

58
Q

What are the rehab goals of tendinopathy?

A

RoM
Address contractile deficits
Address and reinforce movement patterns

59
Q

What are other things to consider in recovery from tendinopathy?

A
Biomechanics 
Flexibility 
Associated injuries 
Lumbar spine / SI joint 
Neural mobility
60
Q

What is the beighton score?

What does it indicate?

A

Hypermobility test

>=4 indicates hypermobility - may be asymptomatic therefore not syndrome

61
Q

Describe the recovery pathway from tendinopathy?

A

Starts with low isometric loading and then progresses to eccentric training and continued load management.

62
Q

What is kinematics?

A

Spatiotemporal characteristics of a movement usually presented by distance, velocity, acceleration in linear and rotational directions

63
Q

What is kinetics of a movement?

A

Force characteristics of a movement- presented by force or torque/moment.

64
Q

Explain the findings in kinematic studies and over use injuries

A

Window of healthy coordinative variability
Increasing leads to increased risk of injury
Decreasing leads to increased risk of injury due to increased concentrated wear on certain tissues.

65
Q

What are the methods used to determine coordinative variability ?

A

Discrete relative phase - time of key events in each of angles profiles
Modified vector coding - spatial measure based on angle angle plot
Continuous relative phase - spatiotemporal measurement based on phase phase generated from angular position and angular velocity of the segments.

66
Q

Give some of the features of iliotibial band syndrome

A

friction between the iliotibal band and underlying lateral epicondyle of the femur mainly in the stance phase
Ache over lateral aspect of knee brought on by running

67
Q

What were the findings, with relation to the leg in the middle of the road, of running on a camber?

A

Less supinated touch down angle
Increased maximal pronation
Increased maximal velocity of pronation
Greater total rearfoot motion
No time difference in time to maximal pronation or to peak acceleration
No change in impact shock as measured by accelerometry.

68
Q

What is the current advice about shoe wearing?

A

Wear shoes that are comfortable

RTC evidence conflicting - motion control of shoe may be helpful

69
Q

What are the findings of BARE foot running?

A

Less injuries but lower running miles
Bare foot - more plantar foot surface injuries and increased calf injuries and decreased knee injuries and plantar fascititis.

70
Q

What is the definition of concussion?

A

subset of mTBI complex pathophysiology process affecting the brain induced by bio mechanical forces (may be direct blow or impact to another part of the body with mechanical force transmitted to head)

71
Q

What are the primary risk factors for concussion?

A

Female, younger, LD and ADHD, history of migraines and history of concussion

72
Q

What are the secondary risk factors for concussion?

A

Immediate dizziness
Migraine Symptoms
Fogginess, difficulty concentrating, vomitting, dizziness, headache, slowness, imbalance or photosensitivity >3 days after injury

73
Q

What is associated with higher severity of concussion?

A

Rotational forces

74
Q

Give some of the clincial presentations of concussion

A

Loss of consciousness
Ataxia
Tonic posturing

  1. Vestibular
  2. Cognitive
  3. Occulomotor
  4. Mood and Anxiety
  5. Cervical
  6. Post traumatic migraine
75
Q

What are the red flags of a suspected concussion that prompt further examination?

A
Deteriorating conscious state 
Increased confusion or irritability
Increased severity of headache
Seizure or convulsions 
Double vision or deafness
Weakness or tingling in legs and arms
76
Q

How is the diagnosis of concussion made?

A

Subjective opinion
Clinical observations
Computer testing

77
Q

What can be used on pitch to identify concussion and what does it test?

A

Maddocks Questions - tests memory

What venue, What half, Who scored last, Did you win last week, Who did you play last week

78
Q

What sort of headache is associated with cervical symptoms of concussion?

A

Mohawk or eye pain headache

79
Q

What test can be done for concussion post match? When should it be completed and why’?

A

SCAT 5
Completed an hour after finishing match - allow time for food and water to stop these impacting on performance

Test is done at the start of the season and provides a basis on which can then assess for the symptoms of concussion

80
Q

Give some examples of cognitive testing

A

Cogsport and impact

81
Q

Explain occulomotor and vestibular testing

A

Occulomotor testing
-Eye movements- nystagmus, convergence, smooth persuit, saccades
- King Devick testing- rapid number naming assessment
Vestibular testing
- BESS - subjective, lack of clinically meaningful assessment, instrument cost, space and personal to conduct test
-Many achieve normal score despite having symptoms when done 2-3 days post injury

82
Q

Explain the return to play post concussion and how this varies based on age

A

Adult
2 Weeks rest and symptom free then a gradual return to play with 24 hours at each stage - earliest return to play is 19 days
U19
2 Weeks rest and symptom free then a gradual return to play with 48 hours at each stage - earliest return to play 23 days

83
Q

Explain why prolonged rest may be counterproductive in concussion

A

Effects on mood, increased use of health care, absence from work or school, physical deconditioning and social isolation.

84
Q

What is important in the recovery from concussion?

A

Monitor athletes for symptoms resolving - education on why symptoms occur may lead to reassurance
Involve MDT- psychology, school/work, coaches and S&C coaches

85
Q

Explain the control of movement and the afferent processes involved

A

Afferent information - occulomotor system, vestibular system, local proprioception and global proprioception- all systems need to be saying the same thing or symptoms develop

86
Q

What is the injury risk post concussion?

A

More likely to experience MSK injuries

87
Q

What needs to be accounted for in rugby with relation to concussion?

A

Rugby stimulates all sensory systems - requires significant coordination
Need adequate strength - every 1 pound increase in neck strength reduces concussion by 5%

88
Q

What was the conculsion of the concussion paper?

A

brief period of cognitive and physical rest appropriate for patients and following this should gradually increase activity. Exact amount of rest not well defined and need more research- close monitored sub-symptom threshold, submaximal exercise may be of benefit.

Best available evidence – doesn’t support efficacy of prescribing complete bed rest for more than a few days.
Bouts of intense physical activity or mental activity can exacerbate symptoms in concussed athletes- transient and need to improve our understanding of pathophysiology and impact on long term outcomes.
Athletes should be encouraged to gradually resume their non-sport activities as tolerated, avoiding heavy exertion and activities that have increased risk of further concussion until cleared.
Prescribing rest should be balanced against possible harms- shortening the rest doesn’t necessarily mean speedier return to sport -multimodal clinical assessment.

89
Q

What were the limitations of the concussion reading?

A

Most studies – low methodological quality ad biased by systematic errors.
Review may be subject to publication bias and language bias as only studies in English
May be other methods of treatment that weren’t included.

Some studies lacked control groups, lack of randomization and lack of control for confounders

90
Q

When are concussive symptoms worse?

A

Vestibular symptoms - worse with rapid head movements, busier more stimulating environments
Cognitive symptoms - worse at the end of the day
Post traumatic migraine - after PA, or vestibular/occulomotor testing

91
Q

What are the functions of a SCAT 5 test?

A

Can be used to aid diagnosis. and see recovery progression- cannot be used as a stand alone method