目的：五十肩的患者常有關節活動度受限的問題，然而臨床上並沒有建立評估肩關節前側及後側緊縮程度的方法。本研究的目的在於⑴分別檢測低胸外展(below-chest abduction)及越胸內收(cross-chest adduction)的測試者內及測試者間信度；⑵分別計算肩關節前側緊縮程度的角度和肩關節外旋角度之問以及肩關節後側緊縮程度的角度和肩關節內旋角度之間的相關性來評量建構效度。方法：十六位平均年齡54.5歲的五十肩患者參與本實驗。分別以以傾斜儀(inclinometer)及量角器(goniometer)量測肩關節前後側緊縮程度及肩關節旋轉角度。結果：以低胸外展及越胸內收分別量測肩關節前側及後側的緊縮程度時有良好(good)的施測者間及施測者內信度(intratester ICC=0.84，0.91；intertester ICC=0.82，0.89)。肩關節前側緊縮程度和肩關節外旋角度之間(R^2=0.499，p=0.003)以及肩關節後側緊縮程度和肩關節內旋角度之間(R^2=0.448，p=0.002)皆有著顯著相關。結論：低胸外展及越胸內收這兩種測試皆有著良好的信度及建構效度。臨床者可推論五十肩患者外旋及內旋方向所減少的關節活動度與其肩關節前後側緊縮程度有關。

Purposes: The purposes of this study were to (1) examine intratester and intertester reliability for measurement of anterior and posterior shoulder tightness in patients with frozen shoulder syndrome (FSS), and (2) assess construct validity by determining the relations between shoulder rotation range of motion (ROM) and shoulder tightness. Methods: Sixteen patients with FSS were recruited. Shoulder internal and external rotation ROM was measured with a goniometer. Anterior and posterior shoulder tightness was measured in below-chest abduction and cross-chest adduction positions with an inclinometer. Results: Both the intratester and intertester reliability for anterior and posterior shoulder tightness were good (intratester ICC=0.84 and 0.91; intertester ICC=0.82 and 0.89). Significant relationships between internal rotation ROM to posterior shoulder tightness (R^2=0.448, p=0.002) and external rotation ROM to anterior shoulder tightness (R^2=0.499, p=0.003) were found in patients with FSS. Conclusions: Below-chest abduction and cross-chest adduction are reliable tests for measurement of anterior and posterior shoulder tightness respectively. The construct of the two tests are valid, so clinicians may make an inference of relationships between decreased shoulder rotation ROM and shoulder tightness in patients with FSS.