Study designs of evaluations included in the review
Prospective randomised controlled trials (RCTs) and quasi-randomised trials that allocated treatments using factors not related to ACL reconstruction, with a minimum of 2 years follow-up, were eligible for inclusion. Comparative trials with a historical control group were excluded.
Specific interventions included in the review
Studies that compared central third BPTB with 4SHS autografts inserted using an arthroscopically assisted technique were eligible for inclusion. All studies used a central third patellar tendon graft with bone blocks for BPTB. Participants undergoing 4SHS received either a doubled semitendinosus and gracilis graft or a quadrupled semitendinosus graft. All but one of the included studies used consistent surgical procedures, but different types of femoral and tibial fixation were used (details were reported). Post-operative rehabilitation varied considerably amongst the studies (details were reported).
Participants included in the review
Inclusion criteria for the participants were not specifically stated, but it was clear that studies of patients undergoing ACL were eligible for inclusion. Where reported, the mean age of the participants in the included studies ranged from 22 to 32 years and the time from injury to surgery ranged from 3 to 42 months. The majority of the participants were male.
Outcomes assessed in the review
The review assessed extension loss, flexion loss, Lachman testing, pivot shift testing, arthrometer testing, return to sports, clinical knee scores, isokinetic muscle testing, patellofemoral joint pain, graft ruptures and other complications. The included studies used different definitions for extension loss (less than 3 degrees loss considered as no loss and 1 degree loss considered to be loss). They also applied different forces during arthrometer testing and used different scoring systems for clinical knee scores.
How were decisions on the relevance of primary studies made?
The authors did not state how the studies were selected for the review, or how many reviewers performed the selection. [A: Two authors independently selected the studies and there were no disagreements.]