2015 ISAKOS Biennial Congress ePoster #1262

Simultaneous Evaluation of Jump-Landing Task with Three-Dimensional Kinematic Analysis and Landing Error Scoring System. Correlation of the Results Obtained from the two Evaluation Methods

Takatoshi Morooka, MD, Nishinomiya, Hyogo JAPAN
Hiroshi Nakayama, MD, Nishinomiya, Hyogo JAPAN
Kaori Kashiwa, MD, Sasayama, Hyogo JAPAN
Shunichiro Kambara, MD, Nishinomiya, Hyogo JAPAN
Tomoya Iseki, MD, NIshinomiya, Hyogo JAPAN
Kenji Kurosaka, MD, Nishinomiya, Hyogo JAPAN
Ryo Kanto, MD, Nishinomiya, Hyogo JAPAN
Shota Morimoto, MD, Nishinomiya, Hyogo JAPAN
Takeo Nagura, MD, PhD, Tokyo JAPAN
Shinichi Yoshiya, MD, Nishinomiya, Hyogo, Hyogo JAPAN

Hyogo College of Medicine, Nishinomiya, Hyogo, JAPAN

FDA Status Cleared

Summary: There was a significant correlation between the LESS score and peak knee valgus angle as well as the peak internal tibial rotation during drop vertical jump test. These study indicate efficacy of the LESS in screening subjects at risk for non-contact ACL injury.




The Landing Error Scoring System (LESS) has been shown to be a reliable clinical screening tool to identify individuals at increased risk of suffering noncontact ACL injury in identifying risky kinematics during the drop vertical jump (DVJ) test; however, correlation between the LESS score and three-dimensional kinematics data are still not clarified, and significance of the LESS has not been fully validated. The purpose of this study was to examine relationship between results of three-dimensional kinematic analysis and LESS score in young female subjects.


Sixteen female healthy volunteers participated in the study (average age; 19.6 years). None of the subjects had any history of major injuries to the trunk and lower extremities.
All subjects performed 3 test DVJ trials according to the LESS protocol described by Padua et al.. Frontal and sagittal view video data were acquired using standard HD video camcorders (HDR-CX560, Sony, Tokyo, Japan) that were positioned according to the LESS protocol. Analysis of the dynamic motion on video images was performed using ImageJ software (Rasband, W.S., ImageJ, U. S. National Institute of Health, Bethesda, Maryland, USA). Simultaneously, three-dimensional kinematics data were collected using an 8-camera motion analysis system (Vicon motion system, Oxford, UK) with ground reaction forces recorded using a force plate. In order to accurately analyze the sequential change in tibio-femoral spatial relationship at the knee, the Point Cluster Technique (PCT) was utilized. The motion analysis was started at the timing of initial toe contact. Maximum (peak) angles measured for flexion, varus/valgus, and tibial rotation during the sequence of dynamic motion were adopted as parameters. Thereafter, correlation between the kinematic results obtained by the PCT and the LESS score was statistically analyzed.


A significant correlation was found between peak knee valgus angle and LESS score (R=0.86, P<0.05). All subjects experienced internal tibial rotation after toe contact, and there was a moderate correlation between the peak internal tibial rotation angle and the LESS score (R=0.36); however, no significant correlation was detected between the peak flexion angle and the LESS score (R=0.15).


There was a correlation between the LESS score and peak knee valgus angle as well as peak internal tibial rotation. Increased internal tibial rotation in combination with valgus has been reported to induce increased force in the ACL. Therefore, the results of this study suggest the efficacy of the LESS in screening subjects at risk for non-contact ACL injury. Consequently, it is thought that screening of large mass population using the LESS may help construct an effective injury prevention program.