Which is More Useful, the “Full Can Test” or the “Empty Can Test,” in Detecting the Torn Supraspinatus Tendon?

Abstract

The purpose of this study was to determine the clinical usefulness of the full can and empty can tests for determining the presence of a torn supraspinatus tendon. The two tests were performed in 143 shoulders of 136 consecutive patients. In each test, the muscle strength was determined by manual muscle testing, and the presence of pain during the maneuver was recorded. We interpreted the tests as positive when there was 1) pain, 2) muscle weakness, or 3) pain or muscle weakness or both. Shoulders were examined by high-resolution magnetic resonance imaging with 95% accuracy for full-thickness rotator cuff tears. There were 35 shoulders with full-thickness tears of the supraspinatus tendon. The accuracy of the tests was the greatest when muscle weakness was interpreted as indicating a torn supraspinatus tendon in both the full can test (75% accurate) and the empty can test (70% accurate). However, there was no significant difference between the accuracy of the tests when this criterion was used. Pain was observed in 62 shoulders (43%) during the full can test and in 71 shoulders (50%) during the empty can test, but the difference was not statistically significant. Muscle weakness should be interpreted as indicative of supraspinatus tendon tear. Using this indicator, both tests are equivalent in terms of accuracy, but considering pain provocation, the full can test may be more beneficial in the clinical setting.

Diagnostic accuracy of clinical examination features for identifying large rotator cuff tears in primary health care

“…28,30,31,42 The majority of previous diagnostic accuracy studies in this area involved patients recruited primarily from surgical waiting lists and investigated only a small number of predominantly physical examination tests, reporting variable accuracy findings. 26,29,32,38,64 Only a limited number of studies estimated the diagnostic accuracy of patient history variables for identifying rotator cuff tears. 28,30,65 Our results support findings from these studies in which older age and the presence of night pain were found to be strong predictors of a rotator cuff tear.…”

“…A negative empty can test has also been reported as sensitive for a supraspinatus tear (sensitivity 89-99%, negative predictive values 93-98%) in surgical settings using the same positive test criteria as defined in our study (pain or weakness). 26,69 The diagnostic value of the empty can test for a rotator cuff (supraspinatus) tear is predicated on the belief that this test predominantly activates the supraspinatus muscle. 53 However, recent work casts doubt on this assumption, 53 reporting that infraspinatus, subscapularis, the upper, middle and lower fibers of trapezius, serratus anterior and all portions of the deltoid muscle were activated to a similarly high level as supraspinatus during the empty can test.…”

“…The majority of previous studies have estimated the diagnostic accuracy of a small number of physical examination tests for identifying rotator cuff tears. [26][27][28][29][30][31] Although 'lag' signs have shown consistently high levels of specificity (88-98%) for large rotator cuff tears in a number of studies, [30][31][32][33][34][35][36][37][38] 28,30,31,43 Yet such questions and tests may provide important information that might enhance the ability of the primary care clinician to diagnose MLM rotator cuff tears. Population differences, methodological concerns and lack of investigation of comprehensive clinical examination variables in previous studies mean the accuracy of the clinical diagnosis of MLM rotator cuff tears in primary care remains largely unknown.…”

Effects of the Shoulder Horn and Lightweight Dumbbell Training on Shoulder External Rotators

“…This effectively trains the shoulder decelerators, including the infraspinatus, teres minor, and deltoid muscles 3,4) . Several exercise programs, including the "emptycan exercise" 5) , "full-can exercise" [6][7][8][9][10] , and "prone full-can exercise" 11) are beneficial in strengthening the supraspinatus. Specific exercise positions progressing from 0° to 90° abduction of the scapular plane should be used in strength training of the shoulder rotators.…”

Effects of Preoperative Evaluation of Rotator Cuff Injuries on the Prediction of the Convalescence Period

“…Itoi et al showed that the level of accuracy of MRI findings for patients with shoulder cuff tears was similar to that of physical examination findings; hence, muscle strength evaluation should be used in the diagnosis of shoulder cuff tears 6) . Murrell et al showed that patients more than 60 years of age who showed two or more of the three signs-impingement, supraspinatus muscle weakness, and decreased external rotational power-had a 98% chance of having rotator cuff injuries 7) .…”