Graft Inclination Angles in Anterior Cruciate Ligament Reconstruction Vary Depending on Femoral Tunnel Reaming Method: Comparison Among Transtibial, Anteromedial Portal, and Outside-In Retrograde Drilling Techniques

Arthroscopy. 2020 Apr;36(4):1095-1102. doi: 10.1016/j.arthro.2019.09.040. Epub 2019 Nov 29.

Abstract

Purpose: To compare graft coronal and sagittal inclination angles in anterior cruciate ligament (ACL) reconstruction performed by different femoral tunnel drilling techniques with respect to intact native ACL.

Methods: In total, 72 patients were prospectively enrolled in the study. The inclusion criteria were complete ACL rupture and patient age between 18 and 55 years. Reconstructions were performed using 4 different femoral tunnel drilling technique: transtibial (TT), anteromedial portal with rigid (AMP-RR) or flexible (AMP-FR) reamer, and outside-in retrograde drilling (OI) techniques. Eighteen patients with intact native ACL were included as controls. Sagittal and coronal graft inclination angles were measured by magnetic resonance imaging 6 months after the procedure by 1 radiologist blinded in regards to the used technique.

Results: OI and AMP-FR techniques allowed for the maintenance of native-like ACL inclination in both the sagittal and coronal planes, whereas TT and AMP-RR increased the sagittal angle by a mean of 9.5° (P < .001) and 6.7° (P = .003), respectively, compared with native ACLs. AMP-RR and TT also showed increased sagittal graft inclination compared with AMP-FR (+6.1°, P = .009 and +9.0°, P < .001, respectively) and OI-drilling techniques (+5.5°, P = .024 and +8.4°, P < .001, respectively). No differences were observed among study groups in terms of coronal graft inclination.

Conclusions: The study hypothesis was partially confirmed, since OI and AMP-FR techniques, but not AMP-RR, using an independent portal for femoral drilling produce a more anatomic graft inclination on the sagittal plane with respect to TT.

Level of evidence: II, prospective comparative study.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Anterior Cruciate Ligament / diagnostic imaging*
  • Anterior Cruciate Ligament / surgery*
  • Anterior Cruciate Ligament Injuries / surgery*
  • Anterior Cruciate Ligament Reconstruction / methods*
  • Female
  • Femur / surgery*
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Prospective Studies
  • Surgical Instruments
  • Young Adult