title: Mechanism of camptocormia in Parkinson's disease analyzed by tilt table-EMG recording.
abstract: BACKGROUND
  We previously classified camptocormia of Parkinson's disease (PD) into upper and lower types based on the inflection point, and reported improvement of upper camptocormia after lidocaine injection into the external oblique. However, the exact pathophysiology of this phenomenon remains obscure.
  
  
  METHODS
  Surface electromyography (sEMG) was recorded in 11 PD patients with upper camptocormia, 11 PD patients with lower camptocormia, and 10 age-matched PD patients without postural deformity. Electrodes were positioned above the external oblique, hip flexors and paraspinal muscles at Th11 level bilaterally. Recording commenced with the patient in supine position on a tilt table, and continued when the table was tilted up to vertical position. Lidocaine was injected into the external oblique in patients with upper camptocormia and the psoas major in patients with lower camptocormia.
  
  
  RESULTS
  All patients with upper and lower camptocormia developed the corresponding camptocormic posture during tilt up. The onset of camptocormic posture was preceded by the appearance of sEMG activity in the external oblique in 10 out of 11 patients with upper camptocormia, but less frequently in patients with lower camptocormia and the controls. Hip flexors sEMG activity was recorded in almost all patients. Posture was improved in 8 out of 9 patients with upper camptocormia, and 9 out of 11 patients with lower camptocormia following injections of lidocaine.
  
  
  CONCLUSIONS
  The results suggest the external oblique is involved, at least in part, in the development of upper camptocormia. Although EMG findings cannot differentiate pathogenicity, the psoas major is probably involved in lower camptocormia.
authors.affiliation: Department of Neurology, National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi-cho, Kodaira, Tokyo, 187-8551, Japan; Department of Neurology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Kofu, 409-3898, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Furusawa
authors.affiliation: Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Kodaira, Tokyo, 187-8551, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Hanakawa
authors.affiliation: Department of Neurology, National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi-cho, Kodaira, Tokyo, 187-8551, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Mukai
authors.affiliation: Department of Rehabilitation, National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi-cho, Kodaira, Tokyo, 187-8551, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Aihara
authors.affiliation: Department of Neurology, National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi-cho, Kodaira, Tokyo, 187-8551, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Taminato
authors.affiliation: Department of Rehabilitation, National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi-cho, Kodaira, Tokyo, 187-8551, Japan.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Iawata
authors.affiliation: Department of Neurophysiology, National Institute of Neuroscience, Kodaira, Tokyo, 187-8551, Japan.
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Takei
authors.affiliation: Department of Neurology, National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi-cho, Kodaira, Tokyo, 187-8551, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Sakamoto
authors.affiliation: Department of Neurology, National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi-cho, Kodaira, Tokyo, 187-8551, Japan. Electronic address: mihom@ncnp.go.jp.
authors.forename: Miho
authors.initials: M
authors.lastname: Murata
mesh_terms: D000009:Abdominal Muscles / Q000503:physiopathology; D000368:Aged; D004576:Electromyography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009134:Muscular Atrophy, Spinal / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D010300:Parkinson Disease / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D013121:Spinal Curvatures / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D018667:Tilt-Table Test / Q000379:methods*
keywords: Camptocormia; Electromyography; External oblique; Lidocaine; Parkinson's disease