Though five‐strand hamstring autografts demonstrate greater graft diameter, postoperative outcomes are equivocal to four‐strand hamstring autograft preparations: a systematic review and meta‐analysis of level I and II studies

Abstract

Purpose To compare graft dimensions, functional outcomes, and failure rates following anterior cruciate ligament reconstruction (ACLR) with either ive-strand or four-strand hamstring autograft options. Methods Three databases (MEDLINE, PubMed, and EMBASE) were searched from inception to 22 April 2023 for level I and II studies comparing ive-and four-strand hamstring autografts in ACLR. The authors adhered to the PRISMA and R-AMSTAR guidelines as well as the Cochrane Handbook for Systematic Reviews of Interventions. Data on demographics, surgical details and rehabilitation, graft diameter, patient-reported outcome measures (PROMs), and rates of positive Lachman test, positive pivot shift test, and graft rupture were extracted. PROMs included Knee Osteoarthritis and Outcome Score (KOOS) subscales, Lysholm, and International Knee Documentation Committee (IKDC). Results One randomized controlled trial (RCT) and four prospective cohort studies with 572 patients were included. Graft diameters were larger in the ive-strand group with a mean diference of 0.93 mm (95% CI 0.61 to 1.25, p < 0.001, I 2 = 66%). The ive-strand group reported statistically higher KOOS ADL subscale and Lysholm scores with a mean diference of 4.85 (95% CI 0.14 to 9.56, p = 0.04, I 2 = 19%) and 3.01 (95% CI 0.48 to 5.53, p = 0.02, I 2 = 0%), respectively. There were no differences in KOOS symptoms, pain, quality of life, or sports subscales, or IKDC scores. There were no diferences in rates of positive Lachman test, positive pivot shift test, or graft rupture with pooled odds ratios of 0.62 (95% CI 0.13 to 2.91, n.s., I 2 = 80%), 0.94 (95% CI 0.51 to 1.75, n.s., I 2 = 31%), and 2.13 (95% CI 0.38 to 12.06, n.s., I 2 = 0%), respectively. Conclusions Although ive-stranded hamstring autografts had signiicantly larger graft diameters compared to four-stranded grafts with a mean diference of 0.93 mm, similar graft rupture rates and clinical laxity assessments were identiied following ACLR. While some PROMs were statistically superior in the ive-stranded hamstring groups, the threshold for the minimal clinical important diference was not reached indicating similar clinical outcomes overall. Level of Evidence Level II.