title: Greater Cervical Muscle Fat Infiltration Evaluated by Magnetic Resonance Imaging is Associated With Poor Postural Stability in Patients With Cervical Spondylotic Radiculopathy.
abstract: METHODS
  A population-based, cross-sectional study.
  
  
  OBJECTIVE
  The aim of this study was to quantitatively evaluate the relationship between static postural stability and fat infiltration within cervical multifidus muscle in patients with cervical spondylotic radiculopathy (CSR).
  
  
  BACKGROUND
  CSR causes denervation by compression of nerve roots. This denervation is detected by fatty infiltration or results in fatty infiltration within muscles. Proprioceptive information in cervical multifidus muscle plays an important role in coordinated movement of postural stability; however, there have been few studies evaluating the relationship between postural stability and fat infiltration within cervical multifidus muscle among CSR patients.
  
  
  METHODS
  Sixteen CSR patients with C6 injuries and 25 age-matched healthy controls underwent magnetic resonance images to examine bilateral cervical multifidus muscle. For evaluation of fat within muscle, a muscle fat index (MFI) was calculated by using both measurement of cervical multifidus muscle and intermuscular fat. Participants' postural stability at upright position with eyes-opened and eyes-closed for 60 seconds was examined by a platform. Two parameters, the total length and the area of the center of pressure (COP), were used for evaluation.
  
  
  RESULTS
  The CSR group showed significantly poorer postural stability than the control group (eyes-opened the total length; P < 0.05, eyes-closed the total length; P < 0.05, eyes-closed the area; P < 0.05). There were significant group differences at C4, C5, and C6 MFI (P < 0.05). In the CSR group, a correlation analysis demonstrated that the age, C4, C5, and C6 MFI values were significantly associated with the eyes-closed the total length of the COP (P < 0.05).
  
  
  CONCLUSIONS
  Fat infiltration within muscle could lead to inhibition of normal activity of musculature. The present study suggests that fat within cervical multifidus muscle could directly cause postural instability in static standing, even though the proprioceptive information has normal lower limbs.
authors.affiliation: *Department of Rehabilitation, Shiroishi Kyoritsu Hospital, Saga, Japan †Division of Cognitive Neuropsychology, Graduate School of Medicine, Saga University, Saga, Japan ‡Department of Physical Therapy, School of Health Sciences at Fukuoka, International University of Health and Welfare, Fukuoka, Japan §Department of Rehabilitation, Takagi Hospital, Fukuoka, Japan ¶Faculty of Rehabilitation Sciences, Nishikyushu University, Saga, Japan ||Department of Neurosurgery, Shiroishi Kyoritsu Hospital, Saga, Japan.
authors.forename: Tsubasa
authors.initials: T
authors.lastname: Mitsutake
authors.forename: Maiko
authors.initials: M
authors.lastname: Sakamoto
authors.forename: Yuji
authors.initials: Y
authors.lastname: Chyuda
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Oka
authors.forename: Hirokatsu
authors.initials: H
authors.lastname: Hirata
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsuo
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Oishi
authors.forename: Etsuo
authors.initials: E
authors.lastname: Horikawa
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology*; D016022:Case-Control Studies; D002574:Cervical Vertebrae / Q000503:physiopathology / Q000601:surgery; D003430:Cross-Sectional Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D009333:Neck / Q000033:anatomy & histology*; D064170:Paraspinal Muscles / Q000033:anatomy & histology; D011187:Posture / Q000502:physiology*; D011843:Radiculopathy / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology*; D055009:Spondylosis / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology*