Comparison of single-bundle and double-bundle isolated posterior cruciate ligament reconstruction with allograft: a prospective, randomized study

Abstract

Purpose: The purpose of this study was to evaluate whether posterior cruciate ligament reconstruction with the double-bundle (DB) technique improved stability of the knee compared with the single-bundle (SB) technique.

Methods: This prospective study included 50 patients who were randomized to undergo posterior cruciate ligament reconstruction by use of tibialis anterior grafts with either the SB technique (25 patients) or DB technique (25 patients). The group assignment was concealed before allocation with the use of sealed envelopes. Posterior stability was evaluated with the KT-1000 arthrometer (MEDmetric, San Diego, CA), and clinical outcomes were assessed with the Lysholm score, Tegner activity score, and International Knee Documentation Committee score (both objective and subjective).

Results: There were 22 patients in the SB group and 24 patients in the DB group with a minimum follow-up period of 2 years. No differences were found between the 2 groups regarding patient demographic data and the duration from injury to operation (P > .05). The Lysholm score was 88.0 ± 4.2 (range, 83 to 93) in the SB group and 89.8 ± 3.8 (range, 86 to 95) in the DB group, and there was no significant difference between the 2 groups (P = .447). The Tegner activity score improved significantly to 6.2 ± 0.9 (range, 5 to 8) in the SB group and 6.8 ± 1.2 (range, 5 to 9) in the DB group. The side-to-side difference in posterior translation decreased to 4.1 ± 1.3 mm (range, 5.5 to 2.5 mm) in the SB group and 2.2 ± 1.3 mm (range, 4.5 to 2.0 mm) in the DB group, and there was a significant difference between the 2 groups (P < .05). According to the International Knee Documentation Committee (both objective and subjective), the DB group had a better grade distribution (P < .05) and had a statistically higher grade (71.6 ± 6.7; range, 63 to 80) than the SB group (65.5 ± 7.8; range, 56 to 75) (P < .05).

Conclusions: Although both techniques resulted in similar patient satisfaction as measured by outcome assessment, the DB procedure significantly improved knee stability.

Level of evidence: Level II, lesser-quality randomized controlled trial.