KEN OKAZAKI    Department   School of Medicine(Tokyo Women's Medical University Hospital), School of Medicine    Position   Professor and Division head
Article types	Original article
Language	English
Peer review	Peer reviewed
Title	Alignment factors affecting the medial meniscus extrusion increases the risk of osteoarthritis development.
Journal	Formal name：Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA Abbreviation：Knee Surg Sports Traumatol Arthrosc ISSN code：14337347/09422056
Domestic / Foregin	Foregin
Volume, Issue, Page	27(8),pp.2617-2623
Author and coauthor	Goto Norio, Okazaki Ken, Akiyama Takenori, Akasaki Yukio, Mizu-Uchi Hideki, Hamai Satoshi, Nakamura Shunsuke, Nakashima Yasuharu
Authorship	2nd author
Publication date	2019/08
Summary	PURPOSE:Varus alignment is known as one of the major causes of medial compartment osteoarthritis (OA). Medial meniscus extrusion also plays a critical role in the in the development of OA. However, studies on the exact relationship between alignment parameters and medial meniscus extrusion are limited. Therefore, this study aimed to investigate this relationship in patients with knee OA.METHODS:Based on a retrospective analysis of the outpatient magnetic resonance imaging (MRI) database, 190 knees were identified to be examined using weight-bearing, whole-leg radiographs and MRIs within 3 months from the first consultation. Subsequently, various parameters of lower leg alignment were measured, which affected the knee varus in radiographs. Finally, a statistical analysis was performed to assess the relationships between the OA grade, distance of medial meniscus extrusion (MME), and alignment parameters; hip-knee-ankle angle (HKAA), percentage of mechanical axis (% MA), medial proximal tibial angle (MPTA), and joint line convergence angle (JLCA). The subjects were divided according to the presence or absence of MME (Group A: MME distance below 3 mm, Group B: MME distance 3 mm and above) to assess the differences in each alignment parameter correlated with MME distance between the groups.RESULTS:MME distance significantly increased with OA grade progression. HKAA, % MA, MPTA, and JLCA significantly correlated with medial meniscus extrusion distance (r = - 0.21, - 0.23, - 0.16, 0.3, respectively). Multiple regression analysis of each significant alignment combined with age, sex, and body mass index revealed that HKAA, % MA, MPTA, and JLCA were significant independent factors of MME distance (P = 0.008, 0.0026, 0.011, 0.0001, respectively).
DOI	10.1007/s00167-018-5286-7
PMID	30456569