The use of intramedullary devices for fixation of metatarsal osteotomies in hallux valgus surgery - A systematic review.

Background: Hallux valgus is a common foot condition with numerous surgical techniques described. Minimally invasive surgery is becoming more popular, with resultant development of suitable fixation devices. The aim of this systematic review was to evaluate the evidence on the use of intramedullary devices in hallux valgus first metatarsal corrective osteotomies, and describe clinical and radiological outcomes, with an overview of techniques and implants used.

Methods: We searched PubMed, Medline, Embase and EMCare databases, conforming to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Radiological outcomes including the hallux valgus angle (HVA) and intermetatarsal angle (IMA) were recorded, as well as clinical outcome scores and complications. Methodological quality of included studies was assessed using the MINORS score.

Results: Ten studies were included, comprising 696 feet in 745 patients. Data pooling and metanalysis was not possible due to overall low quality of evidence. Four implants were reported (Endolog, ISO Plate, V-Tek Plate, Link Fixator) and used with distal first metatarsal osteotomies, with improvement in HVA, IMA, and clinical outcome scores comparable to other fixation techniques. There were no reported cases of non-union. Complication rates were variable (all cause range of 0-21%) across all studies, with an overall low rate.

Conclusion: Intramedullary devices are viable and safe to use for hallux valgus first metatarsal osteotomies, with comparable radiological and functional outcomes to other techniques. Current evidence base is of low methodological quality, therefore high quality studies are required to further evaluate these devices.