Proximal Rotational Metatarsal Osteotomy for Hallux Valgus (PROMO)

Background: Hallux valgus deformity consists of a lateral deviation of the great toe, metatarsus varus, and pronation of the first metatarsal. Most osteotomies only correct varus, but not the pronation of the metatarsal. Persistent postoperative pronation has been shown to increase deformity recurrence and have worse functional outcomes. The proximal rotational metatarsal osteotomy (PROMO) technique reliably corrects pronation and varus through a stable osteotomy, avoiding fusing any healthy joints. The objective of this research is to show a prospective series of the PROMO technique. Methods: Twenty-five patients (30 feet) were operated with the PROMO technique. The sample included 22 women and 3 men, average age 46 years (range 22-59), for a mean prospective follow-up of 1 year (range 9-14 months). Inclusion criteria included symptomatic hallux valgus deformities, absence of severe joint arthritis, or inflammatory arthropathies, with a metatarsal malrotation of 10 degrees or more, with no tarsometatarsal subluxation or arthritis on the anteroposterior or lateral foot radiograph views. The mean preoperative and postoperative Lower Extremity Functional Scale (LEFS) score, metatarsophalangeal angle, intermetatarsal angle, metatarsal malrotation, complications, satisfaction, and recurrence were recorded. Results: The mean preoperative and postoperative LEFS scores were 56 and 73. The median pre-/postoperative metatarsophalangeal angle was 32.5/4 degrees and the intermetatarsal angle 15.5/5 degrees. The metatarsal rotation was satisfactorily corrected in 24 of 25 patients. An Akin osteotomy was needed in 27 of 30 feet. All patients were satisfied with the surgery, and no recurrence or complications were found. Conclusions: PROMO is a reliable technique, with good short-term results in terms of angular correction, satisfaction, and recurrence. Long-term studies are needed to determine if a lower hallux recurrence rate occurs with the correction of metatarsal rotation in comparison with conventional osteotomies. Level of evidence: IV, prospective case series