TY - JOUR
T1 - Frontal Plane Loading Characteristics of Medial Collateral Ligament Strain Concurrent With Anterior Cruciate Ligament Failure
AU - Schilaty, Nathan D.
AU - Bates, Nathaniel A.
AU - Krych, Aaron J.
AU - Hewett, Timothy E.
N1 - Funding Information:
*Address correspondence to Nathan D. Schilaty, DC, PhD, Department of Orthopedic Surgery, Mayo Clinic, Biomechanics Laboratories, 200 First Street SW, Rochester, MN 55905, USA (email: schilaty.nathan@mayo.edu). yDepartment of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota, USA. zSports Medicine Center, Mayo Clinic, Rochester, Minnesota, USA. §Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA. ||Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, Minnesota, USA. {Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio, USA. N.D.S. and N.A.B. contributed equally as co–first authors. One or more of the authors has declared the following potential conflict of interest or source of funding: The authors acknowledge funding from the National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01AR056259 and R01AR055563 to T.E.H. and L30AR070273 to N.D.S.) and from the National Institute of Child Health and Human Development (K12HD065987 to N.D.S.). A.J.K. is a paid consultant for Arthrex Inc and DePuy Orthopedics Inc, receives royalties from Arthrex Inc, and serves on the medical board of trustees for the Musculoskeletal Transplant Foundation. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.
PY - 2019/7/1
Y1 - 2019/7/1
N2 - Background: Both the anterior cruciate ligament (ACL) and the medial collateral ligament (MCL) bear load during athletic tasks of landing, cutting, pivoting, and twisting. As dynamic knee valgus is a purported mechanism for ACL injury, the MCL should bear significant strain load with valgus force. Hypothesis: The intact MCL will demonstrate a significant increase in strain upon failure of the ACL at 25° of knee flexion. Study Design: Controlled laboratory study. Methods: In vivo kinetics/kinematics of 44 healthy athletic participants were measured to determine stratification of injury risk (ie, low, medium, and high) in 3 degrees of knee forces/moments (knee abduction moment, anterior tibial shear, and internal tibial rotation). These stratified kinetic values were input into a cadaveric impact simulator to assess ligamentous strain during a simulated landing task. Uniaxial and multiaxial load cells and differential variable reluctance transducer strain sensors were utilized to collect mechanical data for analysis. Conditions of external loads applied to the cadaveric limbs were varied and randomized. Results: ACL strain increased with increased dynamic knee abduction moment (χ2[5] = 14.123, P =.0148). The most extreme dynamic knee abduction moment condition demonstrated significantly higher ACL strain compared with lower loaded trials (P≤.0203). Similarly, MCL strain increased with dynamic knee abduction moment (χ2[5] = 36.578, P <.0001). Matched-pairs analysis compared ACL strain with MCL strain (maximum ACL strain – maximum MCL strain) and demonstrated high strain for the ACL versus the MCL (S177 = 6223.5, P <.0001). Conclusion: Although significant, MCL strain had minimal increase with increased dynamic knee abduction moment, and the event of ACL failure did not significantly increase MCL strain when compared with high dynamic knee abduction moment conditions in the cadaveric model. The ACL bears more strain than the MCL at increasing amounts of dynamic knee abduction moment at 25° of knee flexion, which may explain the limited concomitant MCL injury rate that can occur during a dynamic valgus collapse of the knee. Clinical Relevance: These characteristics of ACL and MCL strain are important to understand the mechanisms that drive these injuries at the knee and will improve rehabilitation and injury prevention techniques.
AB - Background: Both the anterior cruciate ligament (ACL) and the medial collateral ligament (MCL) bear load during athletic tasks of landing, cutting, pivoting, and twisting. As dynamic knee valgus is a purported mechanism for ACL injury, the MCL should bear significant strain load with valgus force. Hypothesis: The intact MCL will demonstrate a significant increase in strain upon failure of the ACL at 25° of knee flexion. Study Design: Controlled laboratory study. Methods: In vivo kinetics/kinematics of 44 healthy athletic participants were measured to determine stratification of injury risk (ie, low, medium, and high) in 3 degrees of knee forces/moments (knee abduction moment, anterior tibial shear, and internal tibial rotation). These stratified kinetic values were input into a cadaveric impact simulator to assess ligamentous strain during a simulated landing task. Uniaxial and multiaxial load cells and differential variable reluctance transducer strain sensors were utilized to collect mechanical data for analysis. Conditions of external loads applied to the cadaveric limbs were varied and randomized. Results: ACL strain increased with increased dynamic knee abduction moment (χ2[5] = 14.123, P =.0148). The most extreme dynamic knee abduction moment condition demonstrated significantly higher ACL strain compared with lower loaded trials (P≤.0203). Similarly, MCL strain increased with dynamic knee abduction moment (χ2[5] = 36.578, P <.0001). Matched-pairs analysis compared ACL strain with MCL strain (maximum ACL strain – maximum MCL strain) and demonstrated high strain for the ACL versus the MCL (S177 = 6223.5, P <.0001). Conclusion: Although significant, MCL strain had minimal increase with increased dynamic knee abduction moment, and the event of ACL failure did not significantly increase MCL strain when compared with high dynamic knee abduction moment conditions in the cadaveric model. The ACL bears more strain than the MCL at increasing amounts of dynamic knee abduction moment at 25° of knee flexion, which may explain the limited concomitant MCL injury rate that can occur during a dynamic valgus collapse of the knee. Clinical Relevance: These characteristics of ACL and MCL strain are important to understand the mechanisms that drive these injuries at the knee and will improve rehabilitation and injury prevention techniques.
KW - anterior cruciate ligament (ACL)
KW - cadaveric
KW - medial collateral ligament (MCL)
KW - simulation
KW - strain
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U2 - 10.1177/0363546519854286
DO - 10.1177/0363546519854286
M3 - Article
C2 - 31219708
AN - SCOPUS:85068090961
VL - 47
SP - 2143
EP - 2150
JO - American Journal of Sports Medicine
JF - American Journal of Sports Medicine
SN - 0363-5465
IS - 9
ER -