Abstract
INTRODUCTION: This systematic review and meta-analysis of randomized controlled trials (RCTs) aims to compare clinical outcomes and complication profiles of bioabsorbable versus metallic implants in orthopaedic surgery. METHODS: Four databases (PubMed, MEDLINE, EMBASE, CINAHL) were searched from inception to April 8, 2025, for RCTs comparing bioabsorbable and metal implants in orthopaedic procedures. Data were extracted on demographics, implant type, complications, and outcomes. Meta-analyses using random-effects models were performed for pooled comparisons, and heterogeneity was quantified using the I (2) statistic. Risk ratios (RR) and mean differences (MD) were calculated with 95 % confidence intervals (CI). RESULTS: Twenty-seven RCTs involving 1437 patients (738 bioabsorbable, 699 metallic) were included. Overall complication rates were similar between groups (RR: 1.05, 95 % CI: 0.62-1.77, I (2) = 49.8 %, p = 0.85). Bioabsorbable implants had a 15.5 % complication rate compared to 13.3 % for metallic implants. Newer materials showed lower complication rates of 2.5 % for PLLA-HA and 5 % for magnesium compared to 16.5 % for other compounds. There were no foreign body reactions in the studies using newer materials. There was a statistically significant decrease in surgical site infections in the bioabsorbable group (RR: 0.36, 95 % CI: 0.17, 0.79, I (2) = 0 %, p = 0.02). No significant differences were found regarding hardware failure, pain and functional deficiency, and healing rates. Subgroup analysis of ankle procedures (n = 5) showed a higher complication rate in the bioabsorbable group (RR: 3.75, 95 % CI: 1.02, 13.8, I (2) = 25 %, p = 0.05), influenced by one study reporting a 33.7 % foreign body reaction rate. Anterior cruciate ligament reconstruction, foot, and upper limb subgroups showed comparable outcomes. CONCLUSION: Bioabsorbable implants provide comparable complication rates and clinical outcomes to metallic implants across orthopaedic subspecialties. Outcomes may vary by anatomical site and implant generation, with newer bioabsorbable materials demonstrating promising safety profiles. Further long-term studies are warranted to evaluate their performance in high-stress applications and guide clinical decision-making. LEVEL OF EVIDENCE: Level I - Systematic Review of Randomized Controlled Trials.