729 glenohumeral joint are encountered on the anterior aspect of the joint. Chung [9] shows that if a standard anterior fluoroscopic approach is used, the needle may traverse the primary stabilisers. To overcome this drawback a modified anterior approach through the rotator interval can be performed [13]. This is comparable with the US-guided anterior approach. With this approach the needle entry site is at the level between the coracoid process and the superior medial quadrant of the humeral head, which is cranial to the stabilising structures of the shoulder. This limits the risk of compromising diagnostic quality because of leakage of contrast material. This study was not a strict comparative study between US and fluoroscopic techniques because all radiologists kept their own routine, introducing variables like needle size and the use of local anaesthetics. Also the differences in injection skills may play a role. Nevertheless, an important observa- tion of this study is the wide variation in delivered patient care. Although this study is too small to analyse the contribution of different factors to this variation, it is important for physicians to be aware of these phenomena. The results suggest that US-guided glenohumeral joint injection is preferable to fluoroscopic-guided glenohumeral joint injection. To confirm the findings a prospective study without variables such as needle size and local anaesthetics is needed. Furthermore, the number of operators should be extended to minimise the effect of differences in operator skills. Conclusion The four image-guided injection techniques are successful in injection of contrast material into the glenohumeral joint. 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