Background Subacromial impingement (SAI) is a common disorder of the shoulder accounting for about half of all complains of pain in the shoulder.
A number of clinical tests are recommended to identify SAI, however, the accuracy of impingement tests is only moderate when compared to findings on both US and surgery (1;2).
The diagnose SAI is rather unspecific but it is assumed that both tendons and bursa in the shoulder are impinged with the acromial bone in the movement of the shoulder. Impingement may be verified by dynamic US, which allows real time examination of the shoulder joint in motion
Objectives The aim of this cross sectional study was to evaluate the concurrent validity of a number of clinical impingement tests in patients with thickened bursa (≥2mm on US). The validity was calculated using dynamic US examination of the shoulder as gold standard.
Methods Hundred-forty subjects with unspecific shoulder pain were screened for the study. Of these 99 fulfilled the inclusion criteria of having an enlarged bursa (≥2mm) at US examination and no other conditions with could explain the shoulder pain, e.g. tendon ruptures or biceps tenosynovitis. In all subjects five different clinical impingement tests were made by an experienced physiotherapist (Neer, Hawkins, Full can, Empty can, Apprehension test) (3). Subsequent a dynamitic US examination of shoulder abduction was performed by an US specialist unaware of the results of the clinical test. The US impingement test was defined as positive if the tendon and or bursa were impinged at the acromial bone during abduction of the shoulder.
Statistics: Kappa values were calculated.
Results A full and valid data set was present in 93 of the 99 patients. Results are seen in Table 1.
Conclusions The concurrent validity (Kappa) for all the clinical tests of impingement was poor compared to dynamic US and absolute agreement was only seen in about half of the persons. In general the clinical tests assessed the person as having impingement much more often than US did. Misinterpretation could be due to compression of tender and swollen structures in the subacromial space during impingement test
Kelly SM, Brittle N, Allen GM. The value of physical tests for subacromial impingement syndrome: a study of diagnostic accuracy. Clin Rehabil 2010 Feb;24(2):149-58.
Michener LA, Walsworth MK, Doukas WC, Murphy KP. Reliability and diagnostic accuracy of 5 physical examination tests and combination of tests for subacromial impingement. Arch Phys Med Rehabil 2009 Nov;90(11):1898-903.
Cools AM, Cambier D, Witvrouw EE. Screening the athlete’s shoulder for impingement symptoms: a clinical reasoning algorithm for early detection of shoulder pathology. Br J Sports Med 2008 Aug;42(8):628-35.
Disclosure of Interest None Declared