Smart Cavity Creator Drill for Lumbar Interbody Fusion

PROJECT SUMMARYABSTRACT Older patients with persistent and progressive symptoms of chronic back pain and leg pain often have a diagnosis of lumbar degenerative spondyolisthesis and undergo complex lumbar decompression and fusion surgeryOverof these procedures are performed in the United States each yearSurgery is highly effective but technically challengingOne technical challenge of fusion in spondylolisthesis is that after decompressionthere may not be much bone left on the posterior surface of vertebrae for bone graft placementThereforeto improve bone healingsurgeons also perform aninterbody fusionacross the intervertebral disk space between the vertebral bodiesThis part of the surgery requires manipulating nerve rootswhich may be injuredleading to new leg pain after surgery intoof the patientsA surgical technique that requires less or no manipulation of the nerve roots may avoid these poor outcomesWe have developed a drill that creates a cavity across the intervertebral disc space through a small access bore without requiring nerve root manipulationThe cavity can then be filled with bone graft materials to allow fusionHoweverthe drill currently requires manual positioning and control by the surgeonSlight malposition could lead to a catastrophic injury of nearby vital structuresincluding spinal nervesi eparalysisand large blood vesselsi esudden bleeding and deathMost modern surgical suites can now be equipped portable fluoroscopy based CT scannersThere is an opportunity to develop novel imaging and computer driven surgical tools that enable surgeon to perform previously unthinkable complex surgeriesWith these changes in the surgical environmentwe have resurrected our old cavity creation drill with sensors that detect the drill s positiontorque and electrical resistanceWe have developed an anchoring mechanism that tightly attaches the drill to the vertebraewhile preventing the bones from movingWe have also developed precise computer control of drill activation and linear displacementWe are requesting funding to allow refinement of the prototypesmartdrill for use in a sterile surgical environment and conduct in vitro validation in harvested human cadaversSenior orthopedic surgery and neurosurgery residents will train to use the device and then perform procedures on harvested pig lumbar spine specimensWe hypothesize that theSmart Cavity Creatordrill will allow surgeons to precisely control the size and location of the intervertebral cavity to exactly match the preoperative plan and have no failuresi eno violation of vertebral body cortical marginsSBIR funding for prototype refinement and in vitro validation will accelerate development of this potentially disruptive technologyEventuallythis method could lead to a new technique for lumbar interbody fusion with less morbidity PROJECT NARRATIVE Degenerative spondylolisthesis is a forward slippage of one spinal vertebra over an adjacent oneIt is a common cause of back pain in older peopleFusion surgery is effective for relieving symptomsbut the surgery is technically complexDelicate nerve roots can be injured by manipulation during surgeryresulting in new leg pain after surgeryWe propose to complete development and early testing of a smart drill that is partially computer driven to help surgeons perform this procedure with less nerve root manipulation and fewer postsurgical complications