Anatomic single vs. double-bundle ACL reconstruction: a randomized clinical trial–Part 1: clinical outcomes

PURPOSE: Compare clinical outcomes of anatomic single-bundle (SB) to anatomic double-bundle (DB) anterior cruciate ligament reconstruction (ACLR). It was hypothesized that anatomic DB ACLR would result in better International Knee Documentation Committee Subjective Knee Form (IKDC-SKF) scores and reduced anterior and rotatory laxity compared to SB ACLR. METHODS: Active individuals between 14 and 50 years of age that presented within 12 months of injury were eligible to participate. Individuals with prior injury or surgery of either knee, greater than a grade 1 concomitant knee ligament injury, or ACL insertion sites less than 14 mm or greater than 18 mm were excluded. Subjects were randomized to undergo SB or DB ACLR with a 10 mm-wide quadriceps tendon autograft harvested with a patellar bone block and were followed for 24 months. The primary outcome measures included the IKDC-SKF and KT-1000 (side to side difference) and pivot shift tests. Other secondary outcomes included measures of sports activity and participation, range of motion (ROM) and re-injury. RESULTS: Enrollment in the study was suspended due to patellar fractures related to harvest of the patellar bone plug. At that time, 57 subjects had been randomized (29 DB) and two-year follow-up was attained from 51 (89.5%). At 24-month follow-up there were no between-group differences detected for the primary outcomes. Twenty-one (77.8%) DB’s and 20 (83.3%) SB’s reported returning to pre-injury sports 2 years after surgery (n.s) Three subjects (2 DB’s, 5.3% of total) sustained a graft rupture and 5 individuals (4 SB’s, 8.8% of total) had a subsequent meniscus injury. CONCLUSIONS: Due to the early termination of the study, there were no detectable differences in clinical outcome between anatomic SB and DB ACLR when performed with a quadriceps tendon autograft with a bone block in individuals with ACL insertion sites that range from 14 to 18 mm. LEVEL OF EVIDENCE: Level 2 SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00167-021-06585-w.