Timing sequence of multi-planar knee kinematics revealed by physiologic cadaveric simulation of landing: implications for ACL injury mechanism.
BACKGROUND
Challenges in accurate, in vivo quantification of multi-planar knee kinematics and relevant timing sequence during high-risk injurious tasks pose challenges in understanding the relative contributions of joint loads in non-contact injury mechanisms. Biomechanical testing on human cadaveric tissue, if properly designed, offers a practical means to evaluate joint biomechanics and injury mechanisms. This study seeks to investigate the detailed interactions between tibiofemoral joint multi-planar kinematics and anterior cruciate ligament strain in a cadaveric model of landing using a validated physiologic drop-stand apparatus.


METHODS
Sixteen instrumented cadaveric legs, mean 45(SD 7) years (8 female and 8 male) were tested. Event timing sequence, change in tibiofemoral kinematics (position, angular velocity and linear acceleration) and change in anterior cruciate ligament strain were quantified.


RESULTS
The proposed cadaveric model demonstrated similar tibiofemoral kinematics/kinetics as reported measurements obtained from in vivo studies. While knee flexion, anterior tibial translation, knee abduction and increased anterior cruciate ligament strain initiated and reached maximum values almost simultaneously, internal tibial rotation initiated and peaked significantly later (P<0.015 for all comparisons). Further, internal tibial rotation reached mean 1.8(SD 2.5)°, almost 63% of its maximum value, at the time that peak anterior cruciate ligament strain occurred, while both anterior tibial translation and knee abduction had already reached their peaks.


CONCLUSIONS
Together, these findings indicate that although internal tibial rotation contributes to increased anterior cruciate ligament strain, it is secondary to knee abduction and anterior tibial translation in its effect on anterior cruciate ligament strain and potential risk of injury.
Sports Medicine Research Laboratory, Department of Orthopaedic Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States; Engineering Center for Orthopaedic Research Excellence (ECORE), Departments of Orthopaedics and Bioengineering, University of Toledo, Toledo, OH, United States.
Ata M
AM
Kiapour
Sports Health and Performance Institute, The Ohio State University, Columbus, OH, United States; Department of Orthopaedic Surgery, The Ohio State University, Columbus, OH, United States.
Carmen E
CE
Quatman
Engineering Center for Orthopaedic Research Excellence (ECORE), Departments of Orthopaedics and Bioengineering, University of Toledo, Toledo, OH, United States.
Vijay K
VK
Goel
Sports Health and Performance Institute, The Ohio State University, Columbus, OH, United States; Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States.
Samuel C
SC
Wordeman
Sports Health and Performance Institute, The Ohio State University, Columbus, OH, United States; Department of Orthopaedic Surgery, The Ohio State University, Columbus, OH, United States; Department of Biomedical Engineering, The Ohio State University, Columbus, OH, United States; Departments of Physiology and Cell Biology, Family Medicine and the School of Health and Rehabilitation Sciences, The Ohio State University, Columbus, OH, United States.
Timothy E
TE
Hewett
Biomechanics & Injury Mitigation Systems, Research & Exploratory Development Department, The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, United States. Electronic address: constantine.demetropoulos@jhuapl.edu.
Constantine K
CK
Demetropoulos
D000328:Adult; D016118:Anterior Cruciate Ligament / Q000503:physiopathology*; D000070598:Anterior Cruciate Ligament Injuries; D001696:Biomechanical Phenomena / Q000502:physiology; D001703:Biophysics / Q000295:instrumentation; D002102:Cadaver; D005260:Female; D005269:Femur / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D012399:Rotation; D013977:Tibia / Q000502:physiology; D013997:Time Factors
Anterior cruciate ligament; Biomechanics; Cadaveric experiments; Injury; Landing