Test position and reliability in measurements of dorsal neck muscle endurance

Abstract

The aims of the study were to compare the relative electromyographic (EMG) activity of the extensor muscles at three different locations of the spine (cervical, thoracic and lumbar) during three different dorsal neck muscle endurance test procedures, in order to determine the procedure in which the dorsal neck muscles are maximally activated in asymptomatic individuals. The reliability for one of these test procedures was evaluated using an endurance test expressed in seconds in both healthy volunteers and patients with neck discomfort. Surface EMG activity of the spinal extensor muscles was acquired in three different locations during three different test procedures: the “extended neck lift”, and “straight neck lift” with light and heavy loads in 12 healthy volunteers. The “extended neck lift” was assessed for intra-rater reliability in 30 healthy volunteers and 10 patients with neck disorders and for inter-rater reliability in another 30 healthy volunteers and nine patients with neck disorders. EMG activation of the spinal extensor muscles was generally low. Only during the “extended neck lift” was there a slight tendency that cervical extensors were more activated compared with thoracic extensors. The reliability was good (ICC 0.80–0.94); however, the maximal intra-individual differences and the measurement error were large. The different test procedures used are comparable but there was a slight tendency for “the extended neck lift” to be a more selective measurement for the cervical extensors. The “extended neck lift” is reliable and could be appropriate for evaluating groups of patients.

• Electromyography
• endurance tests
• neck muscles
• reliability