Download Shoulder Objective Examination

Shoulder Objective Examination
How to Interpret Special Tests
Special Tests
• Lots of test for different pathologies
• Some tests can be used for different
pathologies
• Interpreting results can be confusing
• Statistics can be used to help ‘Guide’ us
Diagnostic Tests
• Tests can be positive
• Test can be negative
• BUT
• Test might be positive when the pathology may
not be present
• Test might be negative when the pathology is
present
Confused?
Diagnostic Tests
Condition
Present
Condition Not
Present
Test Positive
TRUE POSITIVE FALSE POSITIVE
Test Negative
FALSE
NEGATIVE
TRUE
NEGATIVE
Time for some maths!!!
Diagnostic Tests
Condition
Present
Condition Not
Present
Test Positive
TRUE POSITIVE FALSE POSITIVE
A
B
Test Negative
FALSE
NEGATIVE
C
Sensitivity
A/(A+C)
TRUE
NEGATIVE
D
Specificity
D/(B+D)
E.g
• 100 people have an ACL rupture confirmed through
surgery
• Anterior Draw test was completed on all 100
• It was positive 87 times
• It was therefore negative 13 times
• 50 people did not have an ACL rupture confirmed
through surgery
• Anterior Draw test was completed on all 50
• It was positive 20 times
• It was therefore negative 30 times
• N.B These figures are made up!!
Diagnostic Tests
Condition
Present
Condition Not
Present
Test Positive
87
20
Test Negative
13
30
Sensitivity
87/(87+13)
Specificity
30/(20+30)
E.g
• In the example ACL case the anterior draw test
gives the following properties
• Sensitivity – 87%
• Specificity – 60%
Sensitivity
• Proportion of patients with the condition who
have a positive test result
• Tests with high sensitivity have few false
negative, therefore a negative result RULES
OUT the condition
Specificity
• Proportion of patients without the condition
who have a negative test result
• Tests with high specificity have few false
positive, therefore a positive results RULES IN
the condition
Likelihood Ratios
• Likelihood ratios combine the sensitivity and
specificity of a test
• By doing this you can compare with other test
• You can also work out the probability of tests
being present when test RESULTS are
COMBINED
Likelihood Ratios
• Positive Likelihood
Ratios
• Negative Likelihood
Ratio
– The change in ODDS
favouring the disorder given a
positive test
= ((Sensitivity/(1-Specificity))
– The change in ODDS
favouring the disorder given a
negative test
= ((1-Sensitivity)/Specificity)
• Helpful for RULING IN
• The bigger the better
• Values > 5.0 are useful
• Helpful for RULING OUT
• The smaller the better
• Values < 0.30 are useful
E.G
• Anterior Draw Test
• So from the example of
the anterior draw it is a
– Sensitivity 87%
good test to rule OUT
– Specificity 60%
an ACL tear, but not so
• Positive Likelihood Ratio
good at ruling IN a tear.
 0.87/(1-0.6)
 2.175
• Negative Likelihood
Ratio
 (1-0.87)/0.6
 0.22
Probability and Odds
• To utilise Likelihood ratio we need to know
the pre-test probability and odds
• E.G 25% of knee injuries in population aged
19-15 are ACL ruptures
• Therefore pre-test probability of an ACL
rupture is an 25%
• Pretest odds= ((Pre test probability/ (1-pretest
probability))
Probability and Odds
• Pretest odds= ((Pre test probability/ (1-pretest
probability))
• Pretest odds = ((0.25/(1-0.25))
• Pretest odds = 0.333
• Posttest Odds = Pretest odds X Likelihood
Ratio
Likelihood Ratios
Pre-Test
Odds
Likelihood
Ratio
x
Post Test
Odds
=
0.3
X
2.18
=
0.654
0.3
X
0.22
=
0.066
Probability and Odds
• Posttest Probability = Posttest Odds/(Posttest odds + 1)
• Posttest Probability = 0.65/(0.65+1)
• Posttest Probability = 0.39
• Posttest Probability = 39%
E.G
• So from our example of the ACL injury and
anterior draw
• A positive Anterior Draw
– Increases chance of ACL rupture being present from
• 25% to 39%
• A negative Anterior Draw
– Decreases change of ACL rupture being present from
• 25% to 5%
Likelihood Ratios
• By using likelihood ratios and pretest odds we
can work out the probability of a pathology
being present when multiple tests are
combined
• More positive tests the more chance the
pathology is present
• More negative test the more chance the
pathology isn’t present
The Shoulder
Special Tests
Subacromial Impingement
Test
Sensitivity
Specificity
+ LR
- LR
Neer’s
Hawkins
Kennedy
70.00
52.55
3.95
0.84
78.58
55.08
2.23
0.39
57.20
66.51
2.05
0.69
55.40
58.31
1.92
0.89
47.67
68.41
2.60
0.85
Painful Arc
Supraspinatus/
Empty Can
Resisted
External
Rotation
Subacromial Impingement
80
70
60
50
40
30
20
10
0
Positive
Negative
Subacromial Impingement
100
90
80
70
60
50
40
30
20
10
0
Positive
Negative
Pre Test
Probability
Neers + Hawkins Neers + Hawkins Neers + Hawkins
Kennedy
Kennedy
Kennedy +
+External Rotation External Rotation
+ Painful Arc
Subacromial Impingement
• Published results
– Positive Hawkins Kennedy
– Painful Arc Sign
– Resisted External Rotation
– Positive Likelihood 5.03
(2+); 10.6 (3)
– Post Test Probability 90%
(2+); 95% (3)
(Park et al., 2005)
• Accumulation
–
–
–
–
Positive Neer’s
Positive Hawkins Kennedy
Positive External Rotation
Painful Arc
– Post Test Probability 80%
(2+) 87% (3+) 90% (4)
Anterior Instability
• Apprehension AND Relocation
• Sensitivity
– 81%
• Specificity
– 98%
• + LR
– 39.68
• - LR
– 0.19
Labral Tear
• Apprehension AND Relocation
• Sensitivity
– 38%
• Specificity
– 93%
• + LR
– 5.43
• - LR
– 0.67
Rotator Cuff Tear
• Age > 65 AND Weakness in ER AND Night Pain
• Sensitivity
– 49%
• Specificity
– 95%
• + LR
– 9.84
• - LR
– 0.54
SLAP
• Passive Distraction AND Active Compression
• Sensitivity
– 70%
• Specificity
– 90%
• + LR
– 7.00
• - LR
– 0.11
Does this really help?
• Not really!
• The tests for the shoulder possess poor
diagnostic properties
• Relies on an in depth knowledge of the
properties and a flare with maths
• This only important when referring for further
investigations (ESP Role or Consultant)
Does this really help?
1. Special Tests of the shoulder can help to
guide a diagnosis
2. Grouping of tests can lead to relatively
accurate diagnosis
3. They DO NOT show us what to treat
4. They are inferior to MRI or Arthroscopic
surgery
What should I do?
• Be aware of tests and how to perform them
• Use them in your exam to help differentially
diagnosis if required
• Special Tests are an adjunct to a standard exam
• IMPORTANT Treat what you find from your exam.
• IMPORTANT Refer on if symptoms do not
improve within 3-4 session for accurate
diagnostic tests e.g MRI, Ultrasound etc
References
• Hegedus EJ, Goode A, Campbell S, et al. Physical examination tests
of the shoulder: a systematic review with meta-analysis of
individual tests. Br J Sports Med 2008; 42(2): 80-92; discussion
• Hegedus EJ, Goode AP, Cook CE, et al. Which physical examination
tests provide clinicians with the most value when examining the
shoulder? Update of a systematic review with meta-analysis of
individual tests. Br J Sports Med 2012; 46(14): 964-78.
• Park HB, Yokota A, Gill HS, El Rassi G, McFarland EG. Diagnostic
accuracy of clinical tests for the different degrees of subacromial
impingement syndrome. J Bone Joint Surg Am 2005; 87(7): 1446-55.
• van der Windt DA, Koes BW, de Jong BA, Bouter LM. Shoulder
disorders in general practice: incidence, patient characteristics, and
management. Ann Rheum Dis 1995; 54(12): 959-64.