Retrospective Cohort Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Dec 18, 2017; 8(12): 913-921
Published online Dec 18, 2017. doi: 10.5312/wjo.v8.i12.913
Anterolateral rotatory instability in vivo correlates tunnel position after anterior cruciate ligament reconstruction using bone-patellar tendon-bone graft
Yasutaka Tashiro, Ken Okazaki, Koji Murakami, Hirokazu Matsubara, Kanji Osaki, Yukihide Iwamoto, Yasuharu Nakashima
Yasutaka Tashiro, Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, United States
Yasutaka Tashiro, Ken Okazaki, Koji Murakami, Hirokazu Matsubara, Kanji Osaki, Yukihide Iwamoto, Yasuharu Nakashima, Department of Orthopaedic Surgery, Kyushu University, Fukuoka 812-8582, Japan
Author contributions: Tashiro Y designed the study, performed surgeries and followed up patients; he analyzed the data and drafted the manuscript; Okazaki K assisted designing the study, performed surgeries and followed up patients; he revised the manuscript; Murakami K performed subjective and objective data collection, assisted data analysis and evaluation; Matsubara H and Osaki K performed kinematic data collection, assisted data analysis and evaluation; Iwamoto Y helped grant writing, directed all clinical aspects and co-supervised the entire research; Nakashima Y directed all clinical aspects and supervised the entire research.
Supported by JSPS Fellowships for Research Abroad, No. H27-787; and International Research Fund for Subsidy of Kyushu University School of Medicine Alumni.
Institutional review board statement: This study protocol was approved by the institutional review board (IRB ID: 24-108) of Kyushu University (3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan).
Informed consent statement: All subjects gave their informed consent before they were included to this study.
Conflict-of-interest statement: The authors declare that they have no conflict of interest.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Yasutaka Tashiro, MD, PhD, Department of Orthopaedic Surgery, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. 11yasu@med.kyushu-u.ac.jp
Telephone: +81-92-6425488 Fax: +81-92-6425507
Received: November 22, 2016
Peer-review started: November 23, 2016
First decision: February 17, 2017
Revised: February 23, 2017
Accepted: October 29, 2017
Article in press: October 29, 2017
Published online: December 18, 2017
Abstract
AIM

To quantitatively assess rotatory and anterior-posterior instability in vivo after anterior cruciate ligament (ACL) reconstruction using bone-patellar tendon-bone (BTB) autografts, and to clarify the influence of tunnel positions on the knee stability.

METHODS

Single-bundle ACL reconstruction with BTB autograft was performed on 50 patients with a mean age of 28 years using the trans-tibial (TT) (n = 20) and trans-portal (TP) (n = 30) techniques. Femoral and tibial tunnel positions were identified from the high-resolution 3D-CT bone models two weeks after surgery. Anterolateral rotatory translation was examined using a Slocum anterolateral rotatory instability test in open magnetic resonance imaging (MRI) 1.0-1.5 years after surgery, by measuring anterior tibial translation at the medial and lateral compartments on its sagittal images. Anterior-posterior stability was evaluated with a Kneelax3 arthrometer.

RESULTS

A total of 40 patients (80%) were finally followed up. Femoral tunnel positions were shallower (P < 0.01) and higher (P < 0.001), and tibial tunnel positions were more posterior (P < 0.05) in the TT group compared with the TP group. Anterolateral rotatory translations in reconstructed knees were significantly correlated with the shallow femoral tunnel positions (R = 0.42, P < 0.01), and the rotatory translations were greater in the TT group (3.2 ± 1.6 mm) than in the TP group (2.0 ± 1.8 mm) (P < 0.05). Side-to-side differences of Kneelax3 arthrometer were 1.5 ± 1.3 mm in the TT, and 1.7 ± 1.6 mm in the TP group (N.S.). Lysholm scores, KOOS subscales and re-injury rate showed no difference between the two groups.

CONCLUSION

Anterolateral rotatory instability significantly correlated shallow femoral tunnel positions after ACL reconstruction using BTB autografts. Clinical outcomes, rotatory and anterior-posterior stability were overall satisfactory in both techniques, but the TT technique located femoral tunnels in shallower and higher positions, and tibial tunnels in more posterior positions than the TP technique, thus increased the anterolateral rotation. Anatomic ACL reconstruction with BTB autografts may restore knee function and stability.

Keywords: Anterior cruciate ligament, Patellar tendon, Bone-patellar tendon-bone, Rotatory instability, Magnetic resonance imaging, Tunnel position, Anatomic, Single-bundle

Core tip: Anterolateral rotatory instability was quantitatively assessed in 40 anterior cruciate ligament-reconstructed knees with bone-patellar tendon-bone autografts using a Slocum anterolateral rotatory instability test in open magnetic resonance imaging 1-1.5 years after surgery, and correlated to tunnel positions evaluated by high resolution computed tomography scan 2 wk after surgery. Femoral tunnel positions were shallower (P < 0.01) and higher (P < 0.001), and tibial tunnel positions were more posterior (P < 0.05) in the trans-tibial (TT) group, compared with the trans-portal (TP) group. Anterolateral rotatory translations were significantly correlated with the shallow femoral tunnel positions, and they were greater in the TT group (3.2 ± 1.6 mm) than in the TP group (2.0 ± 1.8 mm) (P < 0.05).