Internal fixation of three-dimensional distal metatarsal I osteotomies in the treatment of hallux valgus deformities using biodegradable magnesium screws in comparison to titanium screws.

BACKGROUND: Various implants, for example K-wires, screws, plates or staples, have been introduced for the stabilisation of corrective osteotomies in hallux valgus surgery. To provide high initial stability and to avoid subsequent implant removal, a novel biodegradable magnesium screw (MAGNEZIX® CS, Syntellix AG, Hanover, Germany) has been developed and approved for clinical use.

METHODS: Between October 2014 and June 2016, magnesium screws were used in 100 patients with a symptomatic hallux valgus deformity for the fixation of Chevron and Youngswick osteotomies. The results were compared to a retrospective cohort of 100 patients, in which titanium screws were applied to stabilize the osteotomies in a comparable manner. All follow-up data was collected retrospectively.

RESULTS: Both cohorts showed no differences concerning the age of patients, comorbidities, number of corrected toes and duration of surgery. The median clinical follow up was 12.2 weeks (magnesium) and 11.7 weeks (titanium), respectively. No difference was found between the magnesium screws and the titanium screws in respect to prolonged wound healing or deep infection. One patient complained about a prominent screw head in the titanium group and one screw fracture was noticed in the magnesium group most probably due to early full weight bearing. All patients but four could start full weight bearing in normal shoes at six weeks.

CONCLUSIONS: Early results of 100 cases of biodegradable magnesium screws in hallux valgus surgery show non-inferior results concerning clinical outcome and complications compared to titanium alloy screws. To avoid implant removal, while keeping high initial stability, magnesium screws are an excellent option in hallux valgus surgery.