title: Association of walking speed with sagittal spinal alignment, muscle thickness, and echo intensity of lumbar back muscles in middle-aged and elderly women.
abstract: BACKGROUND
  Age-related change of spinal alignment in the standing position is known to be associated with decreases in walking speed, and alteration in muscle quantity (i.e., muscle mass) and muscle quality (i.e., increases in the amount of intramuscular non-contractile tissue) of lumbar back muscles. Additionally, the lumbar lordosis angle in the standing position is associated with walking speed, independent of lower-extremity muscle strength, in elderly individuals. However, it is unclear whether spinal alignment in the standing position is associated with walking speed in the elderly, independent of trunk muscle quantity and quality. The present study investigated the association of usual and maximum walking speed with age, sagittal spinal alignment in the standing position, muscle quantity measured as thickness, and quality measured as echo intensity of lumbar muscles in 35 middle-aged and elderly women.
  
  
  METHODS
  Sagittal spinal alignment in the standing position (thoracic kyphosis, lumbar lordosis, and sacral anterior inclination angle) using a spinal mouse, and muscle thickness and echo intensity of the lumbar muscles (erector spinae, psoas major, and lumbar multifidus) using an ultrasound imaging device were also measured.
  
  
  RESULTS
  Stepwise regression analysis showed that only age was a significant determinant of usual walking speed. The thickness of the lumbar erector spinae muscle was a significant, independent determinant of maximal walking speed.
  
  
  CONCLUSIONS
  The results of this study suggest that a decrease in maximal walking speed is associated with the decrease in lumbar erector spinae muscles thickness rather than spinal alignment in the standing position in middle-aged and elderly women.
authors: Department of Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan. masaki.mitsuhiro.27w@st.kyoto-u.ac.jp.
authors: Mitsuhiro
authors: M
authors: Masaki
authors: Department of Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.
authors: Tome
authors: T
authors: Ikezoe
authors: Department of Physical Therapy, Faculty of Rehabilitation, Kobe Gakuin University, Hyogo, 518 Arise, Ikawadani-cho, Nishi-ku, Kobe, 651-2180, Japan.
authors: Yoshihiro
authors: Y
authors: Fukumoto
authors: Department of Occupational Therapy, Faculty of Allied Health Sciences, Yamato University, Osaka, 2-5-1 Katayama-cho, Suita, 564-0082, Japan.
authors: Seigo
authors: S
authors: Minami
authors: Department of Rehabilitation, Kyoto Yawata Hospital, Kyoto, 61 Kawaguchi-Bessho, Yawata, 614-8114, Japan.
authors: Junichi
authors: J
authors: Aoyama
authors: Department of Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.
authors: Satoko
authors: S
authors: Ibuki
authors: Faculty of Health and Medical Science, Kyoto Gakuen University, Kyoto, 1-1 Nanjyo-Otani, Sogabe-cho, Kameoka, 621-8555, Japan.
authors: Misaka
authors: M
authors: Kimura
authors: Department of Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.
authors: Noriaki
authors: N
authors: Ichihashi
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D064131:Back Muscles / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D005260:Female; D006801:Humans; D007564:Japan; D008875:Middle Aged; D009929:Organ Size; D011187:Posture / Q000502:physiology*; D013223:Statistics as Topic; D014463:Ultrasonography / Q000379:methods; D000072797:Walking Speed / Q000502:physiology*
keywords: Aged; Middle-aged; Paraspinal muscles; Posture; Ultrasonography; Walking speed