We treated 34 consecutive articular fractures of the proximal humerus in 33 patients with good bone quality by open reduction and internal fixation. Anatomical or nearly anatomical reduction was achieved in 30, at a mean follow-up of 63 months (25 to 131), complete or partial avascular necrosis had occurred in 12 cases (35%). Two patients subsequently underwent arthroplasty and six further patients required additional surgery. The 32 patients who did not require arthroplasty obtained a mean Constant score of 78 points or 89% of an age- and gender-matched normal score (66 points or 76% in the presence and 83 points or 96% in the absence of avascular necrosis (p < 0.0005)); 22 were painfree, and seven had mild pain and three moderate pain. The mean active anterior elevation was 156°. Internal fixation of complex fractures of the proximal humerus restored good shoulder function if avascular necrosis did not develop.