New clinical test potentially more sensitive in detecting subscapularis tears

Incorporating the bear-hug test into preoperative exams may help surgeons preoperatively predict subscapularis tear size.

A new clinical examination called the bear-hug test may be more accurate for detecting small subscapularis tears than existing standard tests of subscapularis function, a study suggests.

Patients perform the bear-hug test by placing the palm of the affected side on the opposite shoulder with the fingers extended and the elbow positioned anteriorly. The patient then holds the position while the physician tries to pull the patient's hand from the shoulder by applying an external rotation force perpendicular to the forearm, according to the study.

"The test was considered positive if the patient could not hold the hand against the shoulder, or if he or she showed weakness of resisted internal rotation of greater than 20% compared with that of the opposite side. If the strength was comparable to that of the opposite side, without any pain, the test was negative," the authors said.

Johannes R.H. Barth, MD, and colleagues at the San Antonio Orthopaedic Group developed the test and compared it to the lift-off test, the belly-press test and the Napoleon test. The prospective study included 68 shoulders of 49 men and 19 women with an average age of 45.1 ± 14.7 years.

Using diagnostic arthroscopy, the researchers identified 34 rotator cuff tears, including 20 subscapularis tears, yielding a 29.4% prevalence rate of subscapularis tears, according to the study.

The bear-hug test produced eight false-negatives and four false-positives, compared to 12 false-negatives and one false-positive for the belly-press test. The lift-off test produced 14 false-negatives and no false positives, and the Napoleon test produced 15 false-negatives and one false-positive.

The bear-hug test had the highest sensitivity — 60% — compared to a sensitivity of 40% for the belly-press test, 17.6% for the list-off test and 25% for the Napoleon test, according to the study.

The bear-hug test was significantly more sensitive compared to the list-off test and the Napoleon test, but not the belly-press test, the authors noted. However, all four tests had a high specificity, ranging from 91.7% to 100%, with no significant difference among the tests. Also, both the bear-hug and belly-press tests had significantly greater areas under the receiver operating characteristic curve compared to the other two tests, according to the study.

"[The] bear-hug test is the most reliable test on clinical examination for detecting a lesion of the upper part of the subscapularis tendon, and a positive bear-hug test should alert the surgeon to pay particular attention to the subscapularis on arthroscopic evaluation," the authors said.

"The study also confirmed that by performing all of the subscapularis tests, the size of the tear could be suspected preoperatively," they noted.

Tears of at least 30% of the subscapularis were found with positive bear-hug and belly-press tests, but a tear of at least 50% of the subscapularis was needed to produce a positive Napoleon test and of at least 75% for a positive list-off test, according to the study.

"We believe that all of these tests should be performed during the clinical examination to optimize the surgeon's preoperative ability, not only to diagnose a subscapularis tear but also to predict the size of the tear," the authors said.

For more information:
Barth JRH, Burkhart SS, De Beer JF. The bear-hug test: A new and sensitive test for diagnosing a subscapularis tear. Arthroscopy. 2006;22:1076-1084.