A matched pairs comparison of single- versus double-bundle anterior cruciate ligament reconstructions, clinical results and manual laxity testing

Purpose To compare the subjective clinical results as well as manual anterior and rotational stability in patients treated with either single- (SB) or double-bundle (DB) anterior cruciate ligament (ACL) reconstructions. Methods Sixty-four patients who had undergone SB or DB hamstring ACL reconstruction with hamstrings were included in a retrospective matched pair analysis. At follow- up IKDC subjective, CKS, KOOS, CKS and a visual analogue satisfaction scale was assessed. A blinded surgeon examined the joint laxity and completed the objective IKDC. The KT-1000 was used to bilaterally test anterior tibial translation. Patients with confounding variables, which statistically influenced the clinical outcome (passive flexion and extension deficits, persistent quadriceps deficit, tibiofemoral osteoarthritis and non-repairable medial meniscus injury), were identified and excluded from the statistical analysis (n = 10). Results For all subjective scores, DB patients reported increased scores compared with SB patients. While consistently higher scores were demonstrated, statistical significance was only achieved for the IKDC subjective (P = 0.04) and VAS satisfaction (P = 0.02). Graded stability results of the Lachman, anterior drawer and pivotshift tests were significantly higher in the DB group and KT-1000 side-to-side difference was significantly better for DB (P = 0.01). Conclusion DB ACL reconstruction appeared to more consistently result in significantly higher subjective outcome scores and manual tests of joint stability than SB ACL reconstruction. Besides the surgical technique, normal extension and quadriceps strength after surgery were identified to be an essential component in order to provide the patient with a successful outcome.