A device for dimensioning a circumference of a cavity includes a body with a lumen and a distal aperture. The device also includes a longitudinal member extending through the lumen with a distal end and a proximal end. The longitudinal member is capable of slidable movement through the body between retracted and advanced positions. The device also includes a flexible member adapted to conform to a circumference of a cavity contained, e.g., in an intervertebral disc space. The flexible member is operatively connected to a longitudinal member such that upon retraction of the longitudinal member the flexible member retracts into the lumen. When the longitudinal member is moved toward the advanced position, the flexible member is advanced out of the lumen and expands to conform to a dimension which approximates the circumference of the cavity. An apparatus is provided which includes a device for dimensioning a circumference of a cavity and an access member for facilitating conduction of the device to a surgical site, the device adapted and configured to fit within the access member. A kit is provided which includes a working tube incorporating a vertebral distractor, a spreader for assisting and maintaining the vertebral distractor in a distracted configuration, a closing tube for maintaining the working tube in a closed configuration, and a cavity circumference measuring device.