To compare the mechanical effectiveness between performing conventional partial patellectomy and the separate vertical wiring technique for a comminuted fracture of the inferior pole of the patella.

Twenty patellae from cadavers (ten pairs) were used to model acute comminuted fractures of the inferior pole of the patella. Comminuted fractures of the inferior pole of the patellae were made by an oscillating saw. Then they were fixed with separating vertical wiring on one side and the other side received a partial patellectomy by the pull-out suture technique. We measured the maximal lengths between the superior and inferior poles of the normal patella and after fixation. A biomechanical test was then performed to compare the strength of fixation in the two group.

The lengths of patella in the separate vertical wiring group (mean: 5.63 cm) were longer than those in the partial patellectomy group (5.24 cm). The maximal strengths of fixation in the separate vertical wiring (mean: 250.1 Newtons) were higher than in the partial patellectomy (mean: 69.7 Newtons).

A separate vertical wiring is an effective method for fixation of the comminuted fracture of the inferior pole of the patella.