Bioabsorbable Versus Metallic Interference Screw Fixation in Anterior Cruciate Ligament Reconstruction: A Meta-Analysis of Randomized Controlled Trials

PurposeThe aim of the study was to investigate the outcomes between bioabsorbable and metallic screw fixation in anterior cruciate ligament (ACL) reconstruction.MethodsRandomized controlled trials (RCTs) comparing bioabsorbable versus metallic screw fixation in single-bundle ACL reconstruction were identified systematically, and the outcomes were analyzed in terms of infection rate, knee joint effusion, Lysholm score, International Knee Documentation Committee final score, pivot-shift test, and KT-1000/-2000 arthrometer (MEDmetric, San Diego, CA) measurements. The type of grafts was ignored in the meta-analysis. Standard mean difference (SMD) or risk ratio (RR) with 95% confidence interval (CI) was calculated by a fixed-effects or random-effects model. Heterogeneity across the studies was also assessed.ResultsWe included 10 studies comprising 790 patients who were treated by bioabsorbable versus metallic screw fixation for single-bundle ACL reconstruction. The meta-analyzed results of these studies showed that there was no statistically significant difference between bioabsorbable and metallic screw fixation in infection rate (RR, 0.91; P = .87; 320 patients in 5 studies), KT-1000/2000 arthrometer testing (SMD, −0.01; P = .95; 438 patients in 7 studies), pivot-shift testing (RR, 1.06; P = .82; 260 patients in 4 studies), International Knee Documentation Committee final score (RR, 0.87; P = .63; 300 patients in 5 studies), and Lysholm score (SMD, 0.03; P = .89; 204 patients in 4 studies). The incidence of knee effusion was higher in the bioabsorbable screw group (RR, 2.57; P = .04; 421 patients in 4 studies).ConclusionsThere was no significant difference in measurement results of knee joint stability or knee joint function outcome between bioabsorbable and metallic interference screws. Knee joint effusion is more common after ACL reconstruction with bioabsorbable interference screw fixation than with metallic interference screw fixation. More high–methodologic quality randomized controlled trials would be helpful in further meta-analysis.Level of EvidenceLevel I, meta-analysis.