Rate of Tibial Tunnel Malposition Is Not Changed by Drilling Entirely Within the Stump of Preserved Remnants During ACL Reconstruction: A Prospective Comparative 3D-CT Study

• Published in: Orthopaedic journal of sports medicine Vol. 9; no. 10; p. 23259671211037324
• Main Authors: Padua, Vitor Barion C. de, Saithna, Adnan, Chagas, Eduardo Federighi B., Zutin, Tereza Lais M., Piazzalunga, Lucas Fernandes, Patriarcha, Luis Fernando, Gelas, Paulo Jose de Lorenzetti, Helito, Camilo P.
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA SAGE Publications 01-10-2021; Sage Publications Ltd
• Subjects: Ablation; Hypotheses; Knee; Orthopedics; Sports medicine; computed tomography; anatomic ACL reconstruction; ACL reconstruction; remnant preservation; ACL tunnel position
• ISSN: 2325-9671; 2325-9671
• DOI: 10.1177/23259671211037324

Background:
Remnant preservation during anterior cruciate ligament (ACL) reconstruction (ACLR) is controversial, and it is unclear whether the stump aids or obscures tibial tunnel positioning.
Purpose/Hypothesis:
The aim of this study was to determine whether the rate of tibial tunnel malposition is influenced by remnant preservation. The hypothesis was that using a remnant-preserving technique to drill entirely within the tibial stump would result in a significant reduction in tibial tunnel malposition as determined by postoperative 3-dimensional computed tomography (3D-CT).
Study Design:
Cohort study; Level of evidence, 2.
Methods:
Patients undergoing ACLR between October 2018 and December 2019 underwent surgery with a remnant-preserving technique (RP group) if they had a large stump present (>50% of the native ACL length) or if there was no remnant or if it was <50% of the native length of the ACL, they underwent remnant ablation (RA group) and use of standard landmarks for tunnel positioning. The postoperative tunnel location was reported as a percentage of the overall anteroposterior (AP) and mediolateral (ML) dimensions of the tibia on axial 3D-CT. The tunnel was classified as anatomically placed if the center lay between 30% and 55% of the AP length and between 40% and 51% of the ML length.
Results:
Overall, 52 patients were included in the study (26 in each group). The mean tunnel positions were 36.8% ± 5.5% AP and 46.7% ± 2.9% ML in the RP group and 35.6% ± 4.8% AP and 47.3% ± 2.3% ML in the RA group. There were no significant differences in the mean AP (P = .134) and ML (P = .098) tunnel positions between the groups. Inter- and intraobserver reliability varied between fair to excellent and good to excellent, respectively. There was no significant difference in the rate of malposition between groups (RP group, 7.7%; RA group, 11.5%; P ≥ .999).
Conclusion:
Drilling entirely within the ACL tibial stump using a remnant-preserving reconstruction technique did not significantly change the rate of tunnel malposition when compared with stump ablation and utilization of standard landmarks.