POSTER ABSTRACTS - ISAKOS

chronic(31), involving either native or
reconstructed ligaments.
Failures overall ocurred in 28% (9/32) but in
particular 56% of reconstructed ligaments (5/9).
There was no correlation to the treatment of coexistant
pathology and clinical scores remained
high in successful cases, although sporting
function did reduce.
We conclude that despite these results the
technique may avoid the necessity to proceeed to
reconstruction in appropriately selected,
counselled and rehabilitated individuals.
E-poster #377
Analysis of Anatomical and Functional Changes
of Hamstrings Muscles after ACL
Reconstruction
Toru Fukubayashi, Kashiwa, Chiba JAPAN,
Presenter
Yukiko Makihara, Tokyo, JAPAN
Akie Nishino, Tokyo, JAPAN
Akihiro Kanamori, Tsukuba, Ibaragi, JAPAN
Faculty of Sports Sciences, University of Waseda,
Tokorozawa, Saitama, JAPAN
INTRODUCTION: We have previously reported
that the architectural differences of the
semitendinosus (ST) and gracilis (G) have an
influence in the loss of deep knee flexion torque
after anterior cruciate ligament (ACL)
reconstruction. In this study, a detailed analysis of
the anatomical and functional changes of the
hamstring muscles and tendons after ACL
reconstruction was performed.
METHODS: Thirteen athletes who underwent ACL
reconstruction by ipsilateral ST or ST/G tendons
participated in this study. Isometric knee flexion
torque of both limbs at 30, 45, 60, 90 and 105
degrees were recorded with the subjects in a
prone position. At the same time, the
electromyography (EMG) data normalized to 50%
of the maximum voluntary contraction (MVC) for
the ST, semimembranosus (SM) and biceps
femoris (BF) were measured. Transaxial MRI data
was used to calculate the volume of the hamstring
muscles as well as the proximal migration of the
ST.
RESULTS: A significant decrease in torque of the
reconstructed side was shown only at 90 and 105
degrees (p