title: Morphologic differences in intervertebral foramina: a radiographic study of cervical spine positions in asymptomatic men.
abstract: OBJECTIVE
  The purpose of this study was to investigate morphologic differences using plain film radiographs in cervical intervertebral foramina (IVF) for the following positions: neutral; flexion combined with lateral flexion to the right, rotation to the left (FLFR-RL); and flexion combined with lateral flexion to the right, rotation to the right (FLFR-RR.)
  
  
  METHODS
  Fifteen participants (male; age, 22-29 years) with no history of neck pain were recruited to participate in this study. Radiographs were taken with participants standing and their cervical spines positioned in neutral, in FLFR-RL, and in FLFR-RR. Foraminal height and width were measured at levels C5/6 and C6/7 by a radiologist. Differences in IVF sizes between positions were analyzed.
  
  
  RESULTS
  The FLFR-RL position (flexion with contralateral rotation and lateral flexion) increased IVF height at C5/6 by 2.40 mm (24%; P<.01) and C6/7 by 2.64 mm (26%; P<.01) compared with the neutral position. However, no significant increase in foraminal width was observed compared with the neutral position (P>.05), and no significant difference in foraminal height and width increase was observed between FLFR-RL and FLFR-RR.
  
  
  CONCLUSIONS
  The results of this study demonstrate that the cervical FLFR-RL position increases the height of the cervical IVF as measured on radiographs.
authors.affiliation: Department of Physical Therapy, Tokoha University, Shizuoka, Japan. tomo310@mb.imfoweb.ne.jp
authors.forename: Tomonori
authors.initials: T
authors.lastname: Sato
authors.forename: Kenji
authors.initials: K
authors.lastname: Masui
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging* / Q000502:physiology*; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D016059:Range of Motion, Articular / Q000502:physiology*; D012016:Reference Values; D012399:Rotation; D013116:Spinal Cord / Q000000981:diagnostic imaging* / Q000502:physiology*; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult
keywords: Cervical Vertebrae; Posture; Spine Radiculopathy