No difference in survival or subjective treatment failures were found between Double and Single bundle ACL reconstruction techniques in a prospective cohort study of 67,263 patients.
Several randomized studies comparing Double bundle and Single bundle ACL reconstructions have demonstrated moderately better objective knee stability in Double bundle reconstructions but no difference in subjective outcome. Due to the rare incidence of ACL revision procedures, failure outcomes have not been thoroughly investigated.
The aim of the study was to detect and compare the revision rates in Double bundle and Single bundle ACL reconstructed patients from three different registers in Scandinavia. Furthermore to compare the amount of patients in each group that were defined as “subjective treatment failures”, corresponding to a KOOS, Quality of Life subscore less than 44 points.
Study design: Prospective cohort study, Level 2.
Aggregated data from three national Knee ligament injury registries in Denmark, Norway and Sweden, were collected. The inclusion period was from 2004/2005 until December 31st 2014. All patients were registered with a primary ACL reconstruction and aged 14 to 60 years. The reconstructions were performed using hamstring tendon autografts either with a Double bundle or Single bundle technique. Patients with a previous ACL reconstruction in the same knee, or with concominant injury to the PCL, PLC or LCL were excluded. KOOS scores data were collected 1 and 2 years postoperatively and "subjective treatment failure" defined as a KOOS Quality of Life subscore less than 44 points were detected in the two groups. From the aggregated dataset the revision rates at 1, 2, 5 and more than 5 years after surgery were detected and the amount of treatment failures in each group were estimated.
67,263 patients were included in the study. 1,047 patients were reconstructed with a Double bundle hamstring tendon graft, 57,063 with a Single bundle hamstring tendon graft and 9,153 with a Single bundle patellar tendon graft. 4.4% of the patients in the Double bundle group and 4.4% in the Single bundle hamstring tendon group had undergone revision surgery during the study period. There was no difference in the crude risk of revision between the groups (p=0.99) Expected survival of the Double bundle group at 1, 2, 5 and > 5 years follow up were: 99.3%, 98.3%, 96.0%, 95.6%. In the Single bundle group the respective numbers were 99.3%, 97.8%, 96.1%, 95.6%.
25.0% of the patients in the Double bundle group and 28.3% in the Single bundle group achieved less than 44 points in the KOOS QoL subscore, and were defined as subjective treatment failures (p=0.13).
In this large register cohort no differences in graft survival or subjective treatment failure were found between the Single and Double bundle ACL reconstruction techniques.