Distal Rotational Metatarsal Osteotomy (DROMO) for the treatment of hallux valgus associated with first metatarsal pronation: Surgical technique and initial results.

Background: Hallux valgus (HV) is a very common deformity worldwide. Most of the surgical techniques used in the treatment of HV only correct these deformities in two planes, that is sagittal and transverse planes. The importance of the first metatarsal pronation as an etiological factor of hallux valgus is validated by numerous authors and it is usually unaddressed. Few surgical techniques have focused on the correction of rotational deformity of the hallux valgus. We aim to first report a detailed technique and a case series using the Distal Rotational Metatarsal Osteotomy (DROMO) surgical technique, which is less invasive and can address the pronation deformation.

Methods: The inclusion period was 6 months finishing in April 2021. The study analyzed the following x-ray parameters: preoperative and postoperative intermetatarsal angle (IMA), preoperative and postoperative hallux valgus angle (HVA), preoperative and postoperative coronal rotation of the first metatarsal according Hardy and Clapham's classification as described by Kim et al., preoperative and postoperative shape of the first metatarsal head as described by Ono et al. RESULTS: 33 patients matched our inclusion and exclusion criteria. Most patients underwent the surgery for the left foot (n = 18), compared to the right foot (n = 15). We found statistically significant differences between preoperative and postoperative IMA (p < 0.001), preoperative and postoperative HVA (p < 0.001). Preoperative and postoperative coronal rotation of the first metatarsal as classified by Hardy and Clapham was significantly different (p < 0.001), as well as preoperative and postoperative shape of the first metatarsal head (p < 0.01).

Conclusions: DROMO can correct the metatarsal rotation through minimal invasive surgery. From our perspective, DROMO technique should be another alternative for HV correction technique which in time can be associated as a local anesthetic technique, DROMO results are attractive for an ambulatory procedure.