Do bioabsorbable magnesium screws pose any clinical complications compared to standard screws in hallux valgus surgery? A systematic review and meta-analysis

Abstract

Background: Hallux valgus (HV) is a common progressive foot deformity in which the first metatarsophalangeal (MTP) joint is affected, causing significant functional disability and foot pain. The use of biodegradable magnesium screws has gained recent attention for its use in HV surgery. Titanium metallic screws are the standard implants used due to their good mechanical strengths and resistance to corrosion. Despite this, their nondegradable nature means patients often require a second operation to remove the implant. To address this issue, biodegradable magnesium screws have gained recent attention to be evaluated as an alternative fixation tool in HV surgery. Objective: To evaluate the potential complications associated with the biodegradable magnesium screws in HV surgery, with a wider outlook in its application in other orthopaedic procedures. Methods: A systematic review and meta-analysis were performed as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A search of databases identified all studies comparing biodegradable magnesium versus titanium screws in hallux valgus surgery, as well as studies evaluating magnesium screws in other orthopaedic procedures. Post-operative complications, function and pain were the primary outcome measures. Function was assessed using the Ankle Society hallux metatarsophalangeal-interphalangeal scale (AOFAS). In addition, the Visual Analogue Scale (VAS) was utilised for the assessment of pain. Secondary outcomes included operation time and patient satisfaction. Results: Seven studies assessing magnesium screws in HV were identified. A further relevant 13 studies in other orthopaedic procedures were also eligible for inclusion, with a total of 586 participants. In comparison to standard titanium screws, biodegradable magnesium showed comparable AOFAS scores (MD = 3.81, CI = 0.08 to 7.55, P = 0.05) and VAS score (MD = -0.24, CI = -0.56 to 0.08, P = 0.14). However, magnesium screw was associated with various complications, notably early degradation and delayed healing. In terms of the secondary outcomes, there was no statistically significant difference between the two HV groups in terms of operation time and patient satisfaction. Conclusion: While magnesium showed promising postoperative functional and pain outcomes for HV surgery, close attention must be drawn towards its complications leading to unsatisfactory surgical outcomes. Larger studies with long term follow up using different alloys are recommended to comprehensively assess their application in HV surgery.