A modified footplate for the Kerrison rongeur

Abstract

Use of the Kerrison rongeur for bone removal in spinal surgery is associated with dural tears and cerebrospinal fluid (CSF) leaks. We report a modification of the Kerrison rongeur footplate designed to reduce the risk of dural tears. A novel footplate was designed by incorporating the following parameters: (1) tapering the footplate to deflect soft tissue downward during positioning of the rongeur underneath the bone, and (2) making the footplate longer and wider than the cutting element to prevent soft tissue from entering into the cutting surface. Stereolithography models of the modified footplate were made and tested in a cadaver. A stainless steel modified footplate was then incorporated into an existing Kerrison rongeur as a working prototype, and tested in 20 laminectomy cases to clinically validate its design. The modified footplate prevented soft tissue from entering the cutting surface of the Kerrison rongeur in the manner intended by its design. No dural tears or CSF leaks were encountered in any instance. Potential soft tissue compression caused by an increase in footplate dimensions was not a significant issue in the rongeur size tested. This modification, however, might not be practical in rongeurs larger than 3 mm. The risk of dural tears and cerebrospinal fluid leaks in spinal surgery may be reduced by this footplate modification of the Kerrison rongeur. Soft tissue compression may limit the incorporation of this modification to rongeurs of 3 mm or smaller. The promising results warrant further tests with a wider range of sizes.