Flexion and traction effect on C5-C6 foraminal space.

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 degrees 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.