Abstract
The purpose of this cadaveric study was to analyze variation in anterior cruciate
ligament (ACL) tunnel placement between surgeons and the influence of preferred surgical
technique and surgeon experience level using three-dimensional (3D) computed tomography
(CT). In this study, 12 surgeons drilled ACL tunnels on six cadaveric knees each.
Surgeons were divided by experience level and preferred surgical technique (two-incision
[TI], medial portal [MP], and transtibial [TT]). ACL tunnel aperture locations were
analyzed using 3D CT scans and compared with radiographic ACL footprint criteria.
The femoral tunnel location from front to back within the notch demonstrated a range
of means of 16% with the TI tunnels the furthest back. A range of means of only 5%
was found for femoral tunnel low to high positions by technique. The anterior to posterior
tibial tunnel measure demonstrated wider variation than the medial to lateral position.
The mean tibial tunnel location drilled by TT surgeons was more posterior than surgeons
using the other techniques. Overall, 82% of femoral tunnels and 78% of tibial tunnels
met all radiographic measurement criteria. Slight (1–7%) differences in mean tunnel
placement on the femur and tibia were found between experienced and new surgeons.
The location of the femoral tunnel aperture in the front to back plane relative to
the notch roof and the anterior to posterior position on the tibia were the most variable
measures. Surgeon experience level did not appear to significantly affect tunnel location.
This study provides background information that may be beneficial when evaluating
multisurgeon and multicenter collaborative ACL studies.
Keywords
anterior cruciate ligament reconstruction - femoral drilling technique - tunnel placement
variability - CT imaging - ACL - surgeon experience
