Masayoshi Yagi

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BACKGROUND The focus of most anterior cruciate ligament reconstructions has been on replacing the anteromedial bundle and not the posterolateral bundle. HYPOTHESIS Anatomic two-bundle reconstruction restores knee kinematics more closely to normal than does single-bundle reconstruction. STUDY DESIGN Controlled laboratory study. METHODS Ten cadaveric(More)
The anterior cruciate ligament (ACL) can be anatomically divided into anteromedial (AM) and posterolateral (PL) bundles. Current ACL reconstruction techniques focus primarily on reproducing the AM bundle, but are insufficient in response to rotatory loads. The objective of this study was to determine the distribution of in situ force between the two bundles(More)
BACKGROUND The objective of this study was to evaluate the effectiveness of reconstructions of the anterior cruciate ligament to resist anterior tibial and rotational loads. We hypothesized that current reconstruction techniques, which are designed mainly to provide resistance to anterior tibial loads, are less effective in limiting knee instability in(More)
Double-bundle anterior cruciate ligament (ACL) reconstruction reproduces anteromedial and posterolateral bundles, and thus has theoretical advantages over conventional single-bundle reconstruction in controlling rotational torque in vitro. However, its superiority in clinical practice has not been proven. We analyzed rotational stability with three(More)
The objective of this study was to experimentally evaluate a single-bundle versus a double-bundle posterior cruciate ligament reconstruction by comparing the resulting knee biomechanics with those of the intact knee. Ten human cadaveric knees were tested using a robotic/universal force-moment sensor testing system. The knees were subjected to a 134-N(More)
BACKGROUND It is generally thought that tissue regeneration and good functional recovery can be expected after anterior cruciate ligament reconstruction using the hamstring tendons. However, persistent strength deficit in deep knee flexion has also been reported. HYPOTHESIS Morphologic regeneration of the harvested hamstring tendon is not necessarily(More)
BACKGROUND The pivot-shift test is commonly used for assessing dynamic instability in anterior cruciate ligament-insufficient knees, which is related to subjective knee function, unlike static load-displacement measurement. Conventional measurements of 3-dimensional position displacement cannot assess such dynamic instability in vivo and produce comparable(More)
PURPOSE The purpose of this study was to obtain more than 2 years' follow-up after surgery to investigate the effect of the difference in rotatory stability based on our previous data on the clinical outcome among 3 groups: double-bundle (DB) reconstruction group, anteromedial (AM) single-bundle reconstruction group, and posterolateral (PL) single-bundle(More)
The anterior cruciate ligament consists of 2 functional bundles, the anteromedial and the posterolateral bundle. Anterior cruciate ligament reconstruction has traditionally focused on recreating the anteromedial bundle, while the reconstruction of the posteromedial bundle has not routinely been addressed. The authors, from 2 academic centers, present a(More)