Understanding and appreciating human anatomy is emphasized early in our training as sports medicine professionals. Proper palpation and correct special test technique can improve your ability to unravel the injury puzzle and making a definitive diagnosis, especially when considering the complexity of the upper extremity. However, which is more accurate at determining upper extremity pathology? Each has its place in the evaluation, but is one technique (palpation) more sensitive and specific for Type I and Type II subacromial impingement than the other (special tests)? Therefore, the purpose of this study was to determine the diagnostic accuracy of tendon palpation and special tests for diagnosing type I and II subacromial impingement syndrome. For this study, 69 subjects (48 women, 21 men) experiencing shoulder pain related to impingement syndrome lasting 6-12 months, with no history of shoulder surgery, a healthy contralateral shoulder to function as a control, and normal range of motion were recruited. The Neer and Hawkins tests were both examined. In order to validate the palpation techniques, the physiotherapists conducted training to standardize 2 kg of finger pressure by using a pinch grip dynamometer. Once able to consistently apply 1.8-2.2 kg of finger pressure without the dynamometer, the clinicians executed deep soft tissue palpation of the following structures: supraspinatus, infraspinatus, subscapularis and long head of the biceps. A score of 0-3 was used to classify the amount of pain elicited during palpation, with 0 being “no tenderness” and 3 being “severe tenderness.” All unhealthy shoulders underwent sonography, with any of the following findings deemed to be caused by impingement syndrome: partial thickness supraspinatus tear, tendonosis, subacromial/subdeltoid bursitis (SASDB), and tendon calcification. The most common finding was supraspinatus tendonosis (74%), with SASDB and biceps tendon sheath effusion manifesting at similar rates (35% and 33% respectively). Neer and Hawkins tests were positive in 72% and 64% of the subjects, respectively. Palpation tests were positive in the following manner; supraspinatus 84%, infraspinatus 35%, subscapularis 42% and long head of the biceps 65%. These results indicate that the supraspinatus palpation is more accurate than either special test, and that an absence of supraspinatus tenderness indicates an absence of tendon irritation. They also indicate that including supraspinatus palpation in the physical exam makes it more specific for Neer I and II impingement, at least as far as the supraspinatus is involved. They also found that when the Neer test was positive, supraspinatus tendonosis was significantly more prevalent and when the Hawkins tests was positive, partial supraspinatus tears occurred more frequently.
These results are interesting, and a case could be made that palpation tests alone might be enough to differentially diagnose impingement in patients that lack the physical capability of being put through the impingement special tests. One of the more important take home messages is that when SASDB is present, the specificity of all of the palpation tests decreases. However, it is still important to take an accurate and thorough patient history, palpate the surrounding soft tissue structures as well as perform the appropriate special tests in order to make the most appropriate diagnosis. While the Neer and Hawkins tests demonstrated diagnostic accuracy for impingement, the results suggest that if the test is positive there may actually be underlying tendon breakdown and this should be taken into account during examination. Are you surprised that palpation of the supraspinatus tendon is better predictor of impingement than either the Hawkins or Neer impingement tests?
Subacromial Space Decreases at Low Amounts of Abduction