Shoulder Tests

How Valid Are Shoulder Tests?

By Warren Hammer, MS, DC, DABCO

It appears that the validity of almost all of the shoulder tests we perform on a daily basis are in question. This is rather frustrating and brings up questions regarding our treatment locations.

Our soft-tissue treatments and joint manipulations decrease patient pain and often resolve their problems, but if the functional tests we use to determine the sites of pain are controversial, then how do we know we are actually on the source of the pain? If we are not on the source of the pain, how valid is our treatment method? Maybe we don't have to be on the source of the pain. Maybe there is a hands-on mechanism at work that has nothing to do with our theories. Clearly, more studies are needed regarding the effects of soft-tissue treatment and the validity of functional testing.

Lewis states that most orthopedic tests for the shoulder cannot truly isolate a particular structure, since when we use tests that compress or stretch an area, adjacent structures also have to be compressed, stretched or contracted.¹ He feels that these tests are basically symptom or pain tests, especially since although they usually demonstrate a high sensitivity (proportion of actual positives correctly identified), they have a low specificity (proportion of negatives correctly identified). In other words, we are unable to determine the patients who don't have the problem, so that prevents us from determining who really has the problem.

The subacromial bursa is highly innervated and is the largest structure in the subacromial space. Most cuff tests have the effect of stressing this sensitive structure. "The areas of insertion of the individual tendons are large because they each splay and then interdigitate with each other. Therefore, tension in any one musculotendinous unit is distributed, directly or indirectly, over a wide area."² Another problem with interpreting functional tests for the cuff is that the coracohumeral and glenohumeral ligaments act as check-reins that become taut in specific positions and could resist stresses that would otherwise fall exclusively on the tendons of the cuff. "The coracohumeral ligament [appears] to reinforce the supraspinatus tendon, to which it is parallel and firmly adherent."²

Recently, Beaudreuil, et al., and Hegedus, et al., conducted a systematic literature review and selected the studies that reported the best diagnostic accuracy for shoulder clinical tests.^3,4Unfortunately, many tests for degenerative rotator-cuff disease have not been evaluated and some of the ones that were evaluated tested small numbers. They concluded that the diagnostic performance of clinical tests for rotator-cuff tendon disease was fragmentary, but that there were objective data to support the usefulness of some of the tests.

The following tests showed low sensitivity and low specificity: the Neer test at 79 percent and 53 percent, and the Hawkins-Kennedy test at 79 percent and 59 percent. For superior labral (SLAP) tears, the Speed test was 32 percent and 61 percent for sensitivity and specificity, respectively. It was concluded that the Speed test had no diagnostic utility for a SLAP lesion.⁴

With regard to rotator-cuff integrity, only the external-rotation lag sign (ERLS) and drop-arm test demonstrated value as specific tests for a tear of any rotator cuff muscle, but the ERLS was more specific for the infraspinatus. The bear-hug and belly-press tests "appear to be valuable as specific tests for ruling in a subscapularis muscle tendon tear when positive," and the internal rotation lag test for the infraspinatus and the lift-off test for the subscapularis were acceptable.^3,4 Weakness of unresisted active external rotation appeared valid for the infraspinatus.

The Hornblower test showed evidence for a tear or dysfunction of the teres minor or infraspinatus. As this particular test is not commonly used, here is how it is performed: With the patient sitting or standing, the shoulder is externally rotated at 90 degrees of abduction. Examiner supports the arm in the scapular plane. The elbow is flexed to 90 degrees and the patient is asked to rotate the arm externally against the resistance. Positive sign is the inability to maintain the externally rotated position and the arm dropping back to neutral position.

Relatively acceptable tests for instability were the apprehension, relocation and anterior-release tests, especially when apprehension, rather than pain, was used as the definition for a positive test.⁴ If pain is the only response, it is also very possible that we are aggravating the cuff. Research regarding the acromioclavicular (AC) joint stated that the active compression test (horizontal adduction across the chest) "may be diagnostic of AC joint pathology." The biceps load II appeared to be useful in diagnosing a SLAP lesion.

The final answers regarding our cuff tests are still not in. Personally, I will not give up on them. What I realize is that they may not be as specific as I thought, but palpating for localized tenderness that correlates with the positive test adds a dimension that has not been tested. This will be the way I will be interpreting many shoulder tests until a definitive conclusion regarding their value is made.

References

1. Lewis JS. Rotator cuff tendinopathy/subacromial impingement syndrome: Is it time for a new method of assessment? Br J Sports Med, 2009;43:259-64.
2. Clark JM, Harryman DT II. Tendons, ligaments, and capsule of the rotator cuff. Gross and microscopic anatomy. J Bone Joint Surg Am, 1992;74:713-25.
3. Beaudreuil J, Nizard R, Thomas T, et al. Contribution of clinical tests to the diagnosis of rotator cuff disease: a systematic literature review. Joint Bone Spine, 2009;(76):15-9.
4. 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;42:80-92.

Is That Shoulder Test Accurate?

By Warren Hammer, MS, DC, DABCO

We routinely evaluate shoulder problems such as rotator-cuff tendinitis, cuff tears, labral tears (including SLAP lesions), instability, etc., with tests that often are considered valid since they are written up in orthopedic texts and journal articles.

However, it is important to evaluate those tests as to their true validity. As I quoted in a previous Dynamic Chiropracticarticle,¹ most orthopedic tests for the shoulder cannot truly isolate a particular structure, since when we use tests that compress or stretch an area, adjacent structures also have to be compressed, stretched or contracted.

Lewis² feels that these tests are basically symptom or pain tests, especially since although they usually demonstrate a high sensitivity (proportion of actual positives that are correctly identified, i.e., the percentage of sick people who are correctly identified as having the condition), they have a low specificity (the proportion of negatives that are correctly identified, i.e., the percentage of healthy people who are correctly identified as not having the condition). In other words, we are unable to determine the patients who don't have the problem, which prevents us from determining the patients who have the problem.

My 2009 article was based on the findings of Hegedus, et al.,³ who had completed a meta-analysis of shoulder tests the year before. This article is based on Hegedus' findings of a follow-up meta-analysis of shoulder tests for 2012.⁴ In statistics, a meta-analysis refers to methods focused on contrasting and combining results from different studies in the hope of identifying patterns among study results, sources of disagreement among those results, or other interesting relationships that may come to light in the context of multiple studies.⁵

In Hegedus' meta-analysis, he makes us aware of theinherent bias in many studies, such as whether all of the patients were included in the analysis; failure to use a double-blind design; and that many tests with a high sensitivity and specificity have been studied only once (usually by the author of the test) and never confirmed by other scientists. Tests such as the active compression and biceps load II had excellent diagnostic statistics, only to have further research fail to replicate the results of the original authors.⁴

The question arises about testing for subacromial impingement (SIS) which if analyzed as a diagnosis, is a multifactorial shoulder problem that no single test can really evaluate. "Subacromial impingement syndrome (SIS) represents a spectrum of pathology ranging from subacromial bursitis to rotator cuff tendinopathy and full-thickness rotator cuff tears. The relationship between subacromial impingement and rotator cuff disease in the etiology of rotator cuff injury is a matter of debate."⁶

Both extrinsic compression and intrinsic degeneration may play a role, since a bursitis, cuff tear or tendinopathy can all be responsible for the so-called cluster of diagnostic possibilities called an SIS. One of the main tests for SIS is the Hawkins Kennedy, which apparently rules out SIS when it is negative; but this test, along with the Neer test and the painful arc test, has poor specificity and a negative likelihood ratio (-LR), indicating how much the odds of the disease decrease when a test is negative to rule out SIS.

Since there is no single pathognomonic shoulder test, the Hegedus meta-analysis revealed the best test combinations for various shoulder pathologies as follows:⁴

• SLAP: passive distraction and active compression
• Type 2 SLAP: compression-rotation, apprehension, speed
• Labral tear: anterior slide, crank, relocation
• Supraspinatus tendinopathy: age>39, painful arc, self-report of popping or clicking
• Rotator-cuff tear: age> 65, weakness in external rotation (infraspinatus test), night pain
• Subscapularis tendinopathy and possible tear: lift-off, resisted internal rotation
• Anterior instability: apprehension, relocation

For more information regarding any of the tests mentioned in this article, just enter the test name in Google. Performance of these tests is often demonstrated on YouTube.

References

1. Hammer W. "How Valid Are Shoulder Tests?" Dynamic Chiropractic, Oct. 7, 2009.
2. Lewis JS. Rotator cuff tendinopathy/subacromial impingement syndrome: is it time for a new method of assessment? Br J Sports Med, 2009;43:259-264.
3. Hegedus EJ, Goode A, Campbell S, Morin A, et al. Physical examination tests of the shoulder: a systematic review with meta-analysis of individual tests. Br J Sports Med, 2008;42:80-92.
4. Hegedus EJ. 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, July 7, 2012. (Epub ahead of print)
5. Greenland S, O' Rourke K: Meta-Analysis. In: Rothman KJ, Greenland S, Lash T (editors):Modern Epidemiology, 3rd Edition. Lippincott Williams and Wilkins; 2008:652.
6. Harrison AK, Flatow EL. Subacromial impingement syndrome. J Am Acad Orthop Surg, 2011 Nov;19(11):701-8.

A New Functional Shoulder Test

By Warren Hammer, MS, DC, DABCO

At the last soft tissue seminar aboard the Pacific Princess Cruise in the Caribbean, a 55-year-old doctor presented with a very interesting shoulder problem.

He stated that during the course of his working day his shoulder pain steadily increased. He also stated that he had shoulder pain during the night while sleeping on the shoulder. He said that x-rays taken last year revealed sclerosis at the greater tuberosity and some degeneration at the acromioclavicular joint.

The positive findings of a functional examination of the shoulder revealed pain on resistive shoulder abduction and minimal instability when tested in a posterior to anterior stress compared to the opposite shoulder. Stressing the humeral head in a posterior to anterior direction with the arm in abduction (90 degrees), and external rotation (apprehension test) created pain in the anterior capsule compared to the opposite side. Upon questioning, the doctor stated that he injured his shoulder years ago. It is important to realize that a shoulder that reveals anterior instability can, with overuse, exert a traction affect on the rotator cuff muscle/tendon causing pain and possible weakness. The cuff muscles function to compress and depress the humeral head against the glenoid. With instability, in this case excessive anterior humeral translation, the rotator cuff muscles are forced to overwork to maintain humeral stability. Over a period of time, excessive occult or overt anterior translation of the humeral head will eventually fatigue the rotator muscles and create strain and eventual tendinitis.

A new test has recently been devised¹ which determines if instability is etiologically related to tendinitis of the rotator cuff muscles. After the supine apprehension test is performed, with the patient in the apprehension position (abduction 90 degrees, external rotation and slight extension), the examiner reduces the anterior instability position by pushing proximal humerus posterior. At this point, if increasing external rotation is less painful (relieving anterior instability), then you can conclude that the anterior instability is probably primary and the supraspinatus tendinitis (painful resisted abduction) is secondary. While friction massage and modalities on the supraspinatus might relieve the tendinitis, ultimate cure of the problem necessitates increasing the strength and stability of the rotator cuff musculature.

In this case, the passive static tissue (glenoid labrum), capsule or glenohumeral ligaments may be elongated causing a stress on the dynamic stabilizers (rotator cuff muscles).

The doctor was told to have his supraspinatus treated by friction massage to realign scar tissue and improve extensibility of the tendon. He was also told to build up the rotator cuff muscles to improve the stabilization of the humeral head in the glenoid. Exercises should not be performed in extreme external rotation or at 90 degrees shoulder abduction in order to reduce the stress on the anterior capsule and subacromial space. Of course, if the instability is excessive and the patient depends on his shoulder for work or athletics, surgery may be necessary.

This case was interesting in that it demonstrated a weakness in inert tissue (capsule etc.) that eventually affected the contractile tissues (supraspinatus tenoperiosteal insertion). The use of the shoulder reduction test helps us to determine if shoulder instability is related to the causes of shoulder impingement.

References 

1. Jobe, F.W.; Kvitne, R.S. Shoulder Pain in the Overhand Or Throwing Athlete: The Relationship of Anterior Instability and Rotator Cuff Impingement. Orth Rev 1989; 18:963-975.

Labral Tests for the Shoulder Are Not Reliable

By Warren Hammer, MS, DC, DABCO

Practitioners evaluating the cause of shoulder pain and instability rely on particular tests to determine if a labral tear is responsible. The test for a superior labral anterior-posterior (SLAP) lesion, discussed in my Sept.13 article does not appear to be as valid as the author of the test claimed; the same appears true with respect to some of the other tests we commonly use, such as the O'Brien, crank and anterior slide tests. These tests have been accepted as reliable and are found in practically all textbooks on the shoulder.

I recently read two studies in theAmerican Journal of Sports Medicine,^1,2that showed these labral tests were also positive for shoulder conditions, such as impingement, rotator cuff tears and acromioclavicular sprain. The labrum was normal on MRI or arthroscopic examination. Even using multiple labral tests on a patient did not increase diagnostic accuracy.

What a blow! Here I am, pontificating on the shoulder, saying there is "probably a labral tear," when I should be saying there is a slight chance of a labral tear! Performing these tests and feeling for a click or pain, or asking if the pain is deep-seated, is not reliable.

Stetson and Templin² evaluated the crank and O'Brien tests, used to detect glenoid labral tears of the shoulder. They stated that the authors of these tests indicated high sensitivity ratings, and that "there has been no verification or duplication of such results (high sensitivity) by any independent examiners." "Sensitivity" of a test is defined as the probability that patients who truly should have the positive response have that response when the test is performed. "Specificity" of a test is defined as the probability that patients who should truly have a negative response, express a negative response when the test is performed.

As far as the clinician is concerned, "positive predictive value" (PPV) is probably the most important variable. PPV is defined as the probability that a patient who receives a positive test result will truly have a positive response (the actual pathology tested for).³

Stetson and Templin used diagnostic shoulder arthroscopy and magnetic resonance imaging on 65 patients with shoulder pain (average duration of pain: 12 months). Patients had symptoms of night pain, pain in the overhead position, and popping, catching or locking of the shoulder. The mechanism of injury included falls; lifting a heavy object; a direct blow; repetitive overhead activity; traction and pulling injuries; or insidious onset. The authors concluded that none of the above tests were specific for SLAP lesions.

We are taught to rely on functional tests to determine what is going on in our bodies, and accepted orthopedic tests are, at times, proven wrong. For years, I have realized that most orthopedic tests are not very specific, and I have always appreciated functional tests that seem to stress a particular area. What other tests that we use are unreliable? This is why, if we think we have found the cause of a problem, and our treatment does not seem to be effective in a reasonable amount of time, we should rethink the issue.

References

1. McFarland EG, Kim TK, Savino RM. Clinical assessment of three common tests for superior labral anterior-posterior lesions. Amer J of Sports Med 30(6);2002:810-815.
2. Stetson WB, Templin K. The crank test, the O'Brien test, and routine magnetic resonance imaging scans in the diagnosis of labral tears. Amer J of Sports Med 30(6);2002:806-809.
3. Butler DS. The Sensitive Nervous System. Adelaide, Australia; Noigroup Publications;2000:357-358.