The Scarf osteotomy is a commonly used surgical procedure for treating hallux valgus in Europe. Screw fixation is standard practice, although some surgeons now go without internal fixation. Plate fixation is still being studied. The aim of this study was to compare the radiological outcomes of these fixation methods, which has not been performed up to now. Hypothesis : Relative to screw fixation, plate fixation of a Scarf osteotomy of the first metatarsal (M1) prevents secondary impaction, without increasing the complication rate or recurrence rate.

A retrospective study was performed of two internal fixation methods for Scarf osteotomy (screw vs. plate), by analyzing the secondary impaction of the first metatarsal, recurrence of the hallux valgus (angle M1P1>20) on X-rays, incidence of complications and potential discomfort related to the hardware. The osteotomy procedure was the same in both groups: 50patients were included consecutively in each fixation group between February 2014 and November 2015.

The mean follow-up was 13.0±2.7months in the screw group and 12.3±1.1 months in the plate group. There were no severe complications, although four cases of delayed wound healing occurred (3in plate group, 1in screw group). In the screw group, there was one case of secondary impaction, two cases of recurrence (4%) and one case of discomfort. In the plate group, there were no cases of impaction, three recurrences (6%) and five cases of discomfort, leading to plate removal in three of these cases.

There was no significant difference between groups in the M1 secondary impaction rate or recurrence rate: screw fixation did not lead to a higher recurrence rate. Systematic fixation with a locked plate for Scarf osteotomy had no advantages over screw fixation in our study.

II, Comparative study with continuous cohorts.