Abstract Objective: To determine the effects of cervical flexion and traction on foraminal volume and isthmus area at the C5-C6 foraminal space in cadavers. Design: This study evaluated the foraminal space at C5–C6 in cadaver specimens during flexion and traction of the cervical spine. Setting: An orthopedic biomechanics laboratory and department of radiology of a university medical center. Patients or Other Participants: Nine cadaver cervical spines, C1 through T3, were used in the study. Superficial tissues were dissected, preserving the ligaments. Interventions: Proximal and distal portions of the cadaver spines were potted using bone cement. Spines were mounted and imaged with computed tomography in neutral position, 15° of flexion, and maximum flexion with and without 25lbs of axial traction. Main Outcome Measures: The areas and volumes of the foramen were measured and calculated. Results: Flexion alone significantly increased the foraminal volume and isthmus area at C5–C6. Traction resulted in little additional change. Conclusions: For cervical spines with mild to moderate degenerative changes at C5–C6, cervical flexion with or without traction produces significant increases in foraminal volume and area at the foraminal isthmus.