An epidemiological study suggested that the injury mechanism of 'handball goalie's elbow' may be hyperextension. The pathomechanics of hyperextension combined with supination was studied in ten macroscopically normal, male, cadaveric elbow joint specimens. The age of the donors was 28.8 years (range 18-45 years). Extension loading of the elbow was performed in an experimental three-dimensional (3D)-kinematic loading apparatus. The degree of extension increased by 16.7 degrees +/- 8.7 degrees after loading. Hyperextension loads induced significant joint laxity in joint flexion (< 50 degrees) during forced valgus, external and internal rotation, respectively, but not during forced varus. The hyperextension trauma produced three lesions: (1) anterior capsule rupture, (2) avulsion of the proximal insertion of both the medial and the lateral collateral ligaments, and (3) occasional single rupture of the lateral collateral ligament. The lesions indicate that combined hyperextension and supination represent a possible mechanism leading to 'handball goalie's elbow'.