Dimensions of the cervical neural foramina in resting and retracted positions using magnetic resonance imaging.

Study Design: Prospective within-subject experimental design using a sample of convenience.

Objectives: To describe cervical foraminal dimensions in vivo of nonimpaired, asymptomatic individuals in a neutral cervical spine position using magnetic resonance images, and then to document dimensional changes of the foramina when placing the neck in a retracted position.

Background: Physical therapists frequently use movement interventions to treat spine dysfunctio The influence of positional changes of the head and neck on the dimensions of the cervical neuiural foramina is not well documented.