Advanced technology in the evaluation of chronic neck impairment

Abstract: An electrogoniometrical method was modified for clinical motion analysis of the head and neck. Simultaneous measurements of neck motion range and motion pattern in the three planes could be obtained, and a graphical illustration of the movements was possible. The equipment showed high reliability and validity.Electrogoniometry was applied to female traverse crane operators with long-tenn absence from work due to neck complaints after several years' exposure to static occupational stresses. A reduced active neck motion range and motion speed consistent with the clinical picture of chronic trapezius myalgia was found, and a graphical illustration of the character of neck stiffness was obtainable. Due to large variations, the graphs did not allow any specific pathoaoatomic conclusions to be drawn.Electrogoniometry was further applied to fonner steelworks grinders with acquired work incapacity due to chronic neck complaints after long tenn exposure to vigorous upper body vibrations. A decreased active neck motion range and -motion speed was found. The motion pattern, as compared with that of the controls, was frequently altered. The curves showed a high degree of movement irregularities with large variations. Radiographically, the former grinders showed a moderately increased degree of degenerative cervical spine changes, without any certain relation to the obtained motion patterns. The grinders had a moderately decreased vibration sense in the upper and lower extremities. The results suggest an acceleration of the degenerative processes in the cervical spine, also involving the supporting soft tissues of the neck.In patients with suspected cervical vertigo body equilibrimn was examined with the head in predefined positions using combined electrogoniometry and dynamic posturography. Measurements with eyes closed on a sway-referenced forceplate showed a significantly increased body sway in the head position defined by the patients as the one most prone to elicit vertigo or unsteadiness. The difference occurred both when compared with neutral head position and when compared with the most painful head position in patients with neck pain only. An alteration of proprioceptiveafferents from the painful neck seemed to be the most likely cause.In patients with posttraumatic trapezius myalgia the microcirculation and electromyographic responses to local fatigue in the trapezius muscles were examined simultaneously using percutaneous laser-Doppler flowmetry and surface electromyography. At load levels causing local fatigue, an impaired ability to increase the blood flow was demonstrated on the painful side in patients with unilateral pain. In the 'normal' side an ordinary blood flow increase occurred at increased arm elevation angle, shoulder torque and EMG amplitude. A disturbed regulation of the trapezius muscle microcirculation should be considered in the evaluation of patients with posttraumatic chronic neck pain.