The radiographic evaluation of cervical sagittal alignment and stability in Hirayama disease

English Keywords:Hirayama disease  Cervical radiographs  Cervical flexed motion range  Cervical instability  The depth of the cervical lordosis

English Abstract:

  【Abstract】 Objectives: To analyze cervical sagittal alignment and stability in Hirayama disease on radiographs. Methods: From May 2007 to January 2013, 28 patients were diagnosed Hirayama disease, all males, with an average age of 19.5 years(range, 15-24 years). Cervical flexion and extenion radiographs were performed on 28 patients and control subjects(males, average age of 20.9, range from 18 to 23 years). Anterior-posterior(AP) and lateral cervical radiographs were also performed on 21 patients and all control subjects. Cervical flexion motion range, angular mobility and the depth of cervical lordosis were measured. Results: The range of cervical flexion motion(C2-C7) was 37.52°±9.09°, which was significantly greater than that of control subjects(25.39°±8.66°, P<0.05). The angle mobility of lower cervical spine was respectively 14.37°±5.22°, 16.70°±3.44°, 17.05°±3.66° and 15.15°±4.25° in Hirayama disease patients, which was greater than that of control subjects(11.03°±3.67°, 11.69°±3.85°, 13.29°±3.61° and 12.19°±3.55° respectively)(P<0.05）. The depth of the cervical lordosis was 5.42±7.35mm in Hirayama disease group, which was lower than that of control group. 57.1%(12/21) patients showed cervical curvature change or even kyphosis. Conclusions: The increase range of cervical flexion motion, cervical instability and curvature change exist in Hirayama disease. The increase range of cervical flexion motion has correlation with cervical straighten or kyphosis.