Mirco Herbort1, Christoph Domnick2, Michael Johannes Raschke2, Simon Lenschow2, Tim Förster2, Wolf Petersen3, Thore Zantop4. 1. Department of Trauma, Hand and Reconstructive Surgery, Westphalian Wilhelms University Muenster, Muenster, Germany mirco.herbort@uni-muenster.de. 2. Department of Trauma, Hand and Reconstructive Surgery, Westphalian Wilhelms University Muenster, Muenster, Germany. 3. Sporthopaedicum Straubing, Straubing, Germany. 4. Department of Orthopedic and Trauma Surgery, Martin Luther Hospital, Berlin, Germany.
Abstract
BACKGROUND: Anatomic femoral tunnel placement in anterior cruciate ligament (ACL) reconstruction is considered to be a key to good primary stability of the knee. There is still no consensus on whether a centrally placed single bundle in the anatomical femoral footprint can compare with anatomic double-bundle (DB) reconstruction. PURPOSE/HYPOTHESIS: The purpose of this study was to determine knee kinematics after single-bundle ACL reconstruction via the medial portal technique using 2 different femoral tunnel positions and to compare results with those of the anatomic DB technique. The hypotheses were that (1) single-bundle reconstruction using the medial portal technique with a centrally placed femoral tunnel relative to the native footprint (SB-central technique) would more closely restore intact knee kinematics compared with the same reconstruction technique with an eccentric femoral tunnel drilled in the anteromedial bundle footprint (SB-AM technique) and (2) DB reconstruction would result in superior kinematics compared with the SB-central technique. STUDY DESIGN: Controlled laboratory study. METHODS: Knee kinematics was examined in 10 fresh-frozen human cadaveric knees using a robotic/universal force-moment sensor system. Kinematics in simulated pivot-shift and 134-N anterior tibial loading tests were determined in different conditions within the same specimen: (1) intact ACL, (2) deficient ACL, (3) SB-AM, (4) SB-central, and (5) DB. RESULTS: All reconstruction techniques significantly reduced anterior tibial translation (ATT) compared with a deficient ACL at 0°, 15°, 30°, 60°, and 90° in the anterior tibial loading test (P < .01, repeated-measures analysis of variance) and at 0°, 15°, and 30° in the simulated pivot-shift test (P < .001). There were no significant differences in the SB-central group and the DB group compared with the intact ACL. Reconstruction in the SB-AM group resulted in significantly increased ATT compared with the intact ACL in near-to-extension angles in both tests (0°, 15°, and 30°; P < .01). SB-central and DB reconstructions both resulted in significantly reduced ATT, in some tests at ≤30°, compared with SB-AM reconstruction (P < .05). No significant differences between the SB-central and DB groups were found (P > .05). CONCLUSION: The SB-central technique restored intact knee kinematics more closely than did SB-AM reconstruction at time zero. There were no differences in knee kinematics between the DB and SB-central techniques. CLINICAL RELEVANCE: Anatomic single-bundle ACL reconstruction provides similar knee kinematics as anatomic double-bundle reconstruction.
BACKGROUND: Anatomic femoral tunnel placement in anterior cruciate ligament (ACL) reconstruction is considered to be a key to good primary stability of the knee. There is still no consensus on whether a centrally placed single bundle in the anatomical femoral footprint can compare with anatomic double-bundle (DB) reconstruction. PURPOSE/HYPOTHESIS: The purpose of this study was to determine knee kinematics after single-bundle ACL reconstruction via the medial portal technique using 2 different femoral tunnel positions and to compare results with those of the anatomic DB technique. The hypotheses were that (1) single-bundle reconstruction using the medial portal technique with a centrally placed femoral tunnel relative to the native footprint (SB-central technique) would more closely restore intact knee kinematics compared with the same reconstruction technique with an eccentric femoral tunnel drilled in the anteromedial bundle footprint (SB-AM technique) and (2) DB reconstruction would result in superior kinematics compared with the SB-central technique. STUDY DESIGN: Controlled laboratory study. METHODS: Knee kinematics was examined in 10 fresh-frozen human cadaveric knees using a robotic/universal force-moment sensor system. Kinematics in simulated pivot-shift and 134-N anterior tibial loading tests were determined in different conditions within the same specimen: (1) intact ACL, (2) deficient ACL, (3) SB-AM, (4) SB-central, and (5) DB. RESULTS: All reconstruction techniques significantly reduced anterior tibial translation (ATT) compared with a deficient ACL at 0°, 15°, 30°, 60°, and 90° in the anterior tibial loading test (P < .01, repeated-measures analysis of variance) and at 0°, 15°, and 30° in the simulated pivot-shift test (P < .001). There were no significant differences in the SB-central group and the DB group compared with the intact ACL. Reconstruction in the SB-AM group resulted in significantly increased ATT compared with the intact ACL in near-to-extension angles in both tests (0°, 15°, and 30°; P < .01). SB-central and DB reconstructions both resulted in significantly reduced ATT, in some tests at ≤30°, compared with SB-AM reconstruction (P < .05). No significant differences between the SB-central and DB groups were found (P > .05). CONCLUSION: The SB-central technique restored intact knee kinematics more closely than did SB-AM reconstruction at time zero. There were no differences in knee kinematics between the DB and SB-central techniques. CLINICAL RELEVANCE: Anatomic single-bundle ACL reconstruction provides similar knee kinematics as anatomic double-bundle reconstruction.
Authors: Lin Lin; Jing-Sheng Li; Willem A Kernkamp; Ali Hosseini; ChangWan Kim; Peng Yin; Lianxin Wang; Tsung-Yuan Tsai; Peter Asnis; Guoan Li Journal: J Biomech Date: 2016-09-21 Impact factor: 2.712
Authors: Jonathan K Jennings; Daniel P Leas; James E Fleischli; Donald F D'Alessandro; Richard D Peindl; Dana P Piasecki Journal: Orthop J Sports Med Date: 2017-08-07