Acute adhesive capsulitis is a frequent shoulder pathology, characterised by a spontaneous pain onset and a progressive loss of scapular movement. External rotation seems to be most restricted in these patients. Previous studies have shown beneficial effects of physiotherapy. However, the direct effect of the Kaltenborn glenohumeral posterior mobilisation technique on range of motion (ROM), function and pain perception has not been proven yet. This study compared conventional physiotherapy with the glenohumeral posterior mobilisation technique and revealed significant pain decrease, significant increase of external rotation and an improve in function.