caa a22 4500 605458790 CHVBK 20210128100230.0 cr unu---uuuuu 210128e20150401xx s 000 0 eng 10.1007/s00167-014-2931-7 doi (NATIONALLICENCE)springer-10.1007/s00167-014-2931-7 Analysis of displacement and deformation of the medial meniscus with a horizontal tear using a three-dimensional computer model [Elektronische Daten] [Hiroshi Amano, Takehiko Iwahashi, Tomoyuki Suzuki, Tatsuo Mae, Norimasa Nakamura, Kazuomi Sugamoto, Konsei Shino, Hideki Yoshikawa, Ken Nakata] Purpose: The displacement and deformation of the knee meniscus significantly affect its roles; however, little is known about the displacement and deformation patterns of a torn medial meniscus. The objective of this study was to evaluate quantitatively the patterns of displacement and deformation in horizontally torn medial menisci during knee flexion. Methods: Twenty patients with horizontally torn medial menisci underwent three-dimensional (3-D) magnetic resonance imaging at varying degrees of knee flexion, and 3-D computer models of the tibia, tibial articular cartilage, and meniscus were generated. Based on these, the size of the horizontal tear (% tear) was evaluated and defined as the circumferential ratio between the length of the horizontal tear and that of the entire meniscus. The 3-D meniscus models were automatically superimposed over images taken at 0, 20, 40, and 60° of knee flexion by the voxel-based registration method. Meniscal motion and deformation during knee flexion were visualized and quantitatively calculated on the mid-sagittal plane. Correlations between the size of horizontal tear, displacement/deformation of torn menisci, and clinical symptoms were evaluated after conservative treatment for 3months. Results: The % tear was 35.7±12.5% (range 13.7-55.5%). During knee flexion, all torn menisci moved posteriorly, with gradual widening of horizontal and vertical gaps (p<0.05). A direct correlation was observed between % tear and change in the vertical tear gap during knee flexion (p<0.05). There was an inverse correlation between Lysholm score and % tear (p<0.05). Conclusion: Medial meniscal horizontal tears widen and deform during knee flexion, and % tear correlates with the change in the vertical gap. Patients with a lower % tear are more capable of performing activities of daily living after conservative treatment. This method may help clarify the cause of pain in patients with medial meniscus tears as well as facilitate the selection of an appropriate treatment plan. Level of evidence: Case series, Level IV. Springer-Verlag Berlin Heidelberg, 2014 Horizontally torn medial meniscus nationallicence MRI nationallicence 3-D computer model nationallicence Movement and deformation nationallicence Amano Hiroshi Department of Sports Orthopedics, Osaka Rosai Hospital, 1179-3 Nagasone-cho, Kita-ku, 591-8025, Sakai, Osaka, Japan aut Iwahashi Takehiko Department of Orthopedics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, 565-0871, Suita, Osaka, Japan aut Suzuki Tomoyuki Department of Orthopedic Surgery, Sapporo Medical University School of Medicine, S1-w16, Chu-ou-ku, 060-8543, Sapporo, Japan aut Mae Tatsuo Department of Orthopedics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, 565-0871, Suita, Osaka, Japan aut Nakamura Norimasa Faculty of Rehabilitation Science, Osaka Health Science University, 1-9-27, Temma, Kita-ku, 530-0043, Osaka, Japan aut Sugamoto Kazuomi Locomotor Biomaterial Limited to the Joint Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, 565-0871, Suita, Osaka, Japan aut Shino Konsei Osaka Yukioka College of Health Science, 1-1-41, Sojiji, 567-0801, Ibaraki, Osaka, Japan aut Yoshikawa Hideki Department of Orthopedics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, 565-0871, Suita, Osaka, Japan aut Nakata Ken Department of Health and Sport Sciences, Osaka University Graduate School of Medicine, 1-17, Machikaneyama, 560-0043, Toyonaka, Osaka, Japan aut Knee Surgery, Sports Traumatology, Arthroscopy Springer Berlin Heidelberg 23/4(2015-04-01), 1153-1160 0942-2056 23:4<1153 2015 23 167 https://doi.org/10.1007/s00167-014-2931-7 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00167-014-2931-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Amano Hiroshi Department of Sports Orthopedics, Osaka Rosai Hospital, 1179-3 Nagasone-cho, Kita-ku, 591-8025, Sakai, Osaka, Japan aut NATIONALLICENCE 700 1- Iwahashi Takehiko Department of Orthopedics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, 565-0871, Suita, Osaka, Japan aut NATIONALLICENCE 700 1- Suzuki Tomoyuki Department of Orthopedic Surgery, Sapporo Medical University School of Medicine, S1-w16, Chu-ou-ku, 060-8543, Sapporo, Japan aut NATIONALLICENCE 700 1- Mae Tatsuo Department of Orthopedics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, 565-0871, Suita, Osaka, Japan aut NATIONALLICENCE 700 1- Nakamura Norimasa Faculty of Rehabilitation Science, Osaka Health Science University, 1-9-27, Temma, Kita-ku, 530-0043, Osaka, Japan aut NATIONALLICENCE 700 1- Sugamoto Kazuomi Locomotor Biomaterial Limited to the Joint Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, 565-0871, Suita, Osaka, Japan aut NATIONALLICENCE 700 1- Shino Konsei Osaka Yukioka College of Health Science, 1-1-41, Sojiji, 567-0801, Ibaraki, Osaka, Japan aut NATIONALLICENCE 700 1- Yoshikawa Hideki Department of Orthopedics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, 565-0871, Suita, Osaka, Japan aut NATIONALLICENCE 700 1- Nakata Ken Department of Health and Sport Sciences, Osaka University Graduate School of Medicine, 1-17, Machikaneyama, 560-0043, Toyonaka, Osaka, Japan aut NATIONALLICENCE 773 0- Knee Surgery, Sports Traumatology, Arthroscopy Springer Berlin Heidelberg 23/4(2015-04-01), 1153-1160 0942-2056 23:4<1153 2015 23 167