Yasutaka Tashiro1, Vani Sundaram2, Eric Thorhauer2, Tom Gale2, William Anderst2, James J Irrgang2, Freddie H Fu2, Scott Tashman2. 1. Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, U.S.A.; Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. Electronic address: ytashiro11@gmail.com. 2. Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, U.S.A.
Abstract
PURPOSE: To determine the in vivo dynamic graft bending angle (GBA) in anterior cruciate ligament (ACL)-reconstructed knees, correlate the angle to tunnel positions and tunnel widening, and evaluate the effects of 2 femoral tunnel drilling techniques on GBA. METHODS: Patients with an isolated ACL injury undergoing reconstruction from 2011 to 2012 were included. Transportal techniques were used to create femoral tunnels. Tunnel locations were determined by 3-dimensional computed tomography. Tibiofemoral kinematics during treadmill walking and running were assessed by dynamic stereo x-ray analysis 6 months and 2 years postoperatively. The GBA was calculated from the 3-dimensional angle between the graft and femoral tunnel vectors on each motion frame. The cross-sectional areas of femoral tunnels were measured at 6 months and compared with the initial size to assess tunnel widening. RESULTS: A total of 54 patients were included. Use of flexible drills resulted in significantly higher GBAs during walking (80.6° ± 7.8°, P < .001) and running (80.5° ± 9.0°, P = .025) than rigid drills (walking, 67.5° ± 9.3°; running, 74.1° ± 9.6°). Their use led to greater tunnel widening of 113.9% ± 17.6%, as compared with 97.7% ± 17.5% for rigid drills (P = .003). The femoral and tibial apertures were located in similar anatomic positions in both groups, but the femoral tunnel exits were located more anteriorly (P < .001) in the flexible drill group. A higher GBA was highly correlated with anterior location of femoral exits (r = 0.63, P < .001) and moderately correlated with greater tunnel widening (r = 0.48, P < .001). CONCLUSIONS: High GBAs were identified during dynamic activities after anatomic ACL reconstruction with a transportal femoral tunnel drilling technique. The GBA was greater when flexible drills were used. The high bending angle resulted from the more anterior location of the femoral tunnel exits, and it correlated with early bone tunnel widening at 6 months. These results suggest that a high GBA may increase stress at the bone-graft interface and contribute to greater tunnel widening after anatomic ACL reconstruction, although the clinical impact should be further investigated. LEVEL OF EVIDENCE: Level III, retrospective comparative study.
PURPOSE: To determine the in vivo dynamic graft bending angle (GBA) in anterior cruciate ligament (ACL)-reconstructed knees, correlate the angle to tunnel positions and tunnel widening, and evaluate the effects of 2 femoral tunnel drilling techniques on GBA. METHODS:Patients with an isolated ACL injury undergoing reconstruction from 2011 to 2012 were included. Transportal techniques were used to create femoral tunnels. Tunnel locations were determined by 3-dimensional computed tomography. Tibiofemoral kinematics during treadmill walking and running were assessed by dynamic stereo x-ray analysis 6 months and 2 years postoperatively. The GBA was calculated from the 3-dimensional angle between the graft and femoral tunnel vectors on each motion frame. The cross-sectional areas of femoral tunnels were measured at 6 months and compared with the initial size to assess tunnel widening. RESULTS: A total of 54 patients were included. Use of flexible drills resulted in significantly higher GBAs during walking (80.6° ± 7.8°, P < .001) and running (80.5° ± 9.0°, P = .025) than rigid drills (walking, 67.5° ± 9.3°; running, 74.1° ± 9.6°). Their use led to greater tunnel widening of 113.9% ± 17.6%, as compared with 97.7% ± 17.5% for rigid drills (P = .003). The femoral and tibial apertures were located in similar anatomic positions in both groups, but the femoral tunnel exits were located more anteriorly (P < .001) in the flexible drill group. A higher GBA was highly correlated with anterior location of femoral exits (r = 0.63, P < .001) and moderately correlated with greater tunnel widening (r = 0.48, P < .001). CONCLUSIONS: High GBAs were identified during dynamic activities after anatomic ACL reconstruction with a transportal femoral tunnel drilling technique. The GBA was greater when flexible drills were used. The high bending angle resulted from the more anterior location of the femoral tunnel exits, and it correlated with early bone tunnel widening at 6 months. These results suggest that a high GBA may increase stress at the bone-graft interface and contribute to greater tunnel widening after anatomic ACL reconstruction, although the clinical impact should be further investigated. LEVEL OF EVIDENCE: Level III, retrospective comparative study.
Authors: Asheesh Bedi; Volker Musahl; Volker Steuber; Daniel Kendoff; Dan Choi; Answorth A Allen; Andrew D Pearle; David W Altchek Journal: Arthroscopy Date: 2010-10-29 Impact factor: 4.772
Authors: Jae Gyoon Kim; Min Ho Chang; Hong Chul Lim; Ji Hoon Bae; Seung Yup Lee; Jin Hwan Ahn; Joon Ho Wang Journal: Arthroscopy Date: 2015-03-29 Impact factor: 4.772
Authors: Andrew Duffee; Robert A Magnussen; Angela D Pedroza; David C Flanigan; Christopher C Kaeding Journal: J Bone Joint Surg Am Date: 2013-11-20 Impact factor: 5.284
Authors: Kanto Nagai; Yasutaka Tashiro; Elmar Herbst; Tom Gale; Joon Ho Wang; James J Irrgang; William Anderst; Freddie H Fu Journal: Knee Surg Sports Traumatol Arthrosc Date: 2018-06-04 Impact factor: 4.342
Authors: Do Kyung Lee; Jun Ho Kim; Byung Hoon Lee; Hyeonsoo Kim; Min Jae Jang; Sung-Sahn Lee; Joon Ho Wang Journal: Orthop J Sports Med Date: 2021-10-22
Authors: Thomas E Moran; Anthony J Ignozzi; Eric R Taleghani; Amelia S Bruce; Joseph M Hart; Brian C Werner Journal: Orthop J Sports Med Date: 2022-03-16