Electronic Ligament Balancing for Knee Arthroplasty

Despite the overall success of total knee arthroplasty in relieving painpatient reported dissatisfaction rates are highImprovement in implant design and crosslinked polyethylene have reduced revision rates due to implant loosening and polyethylene wearHoweverligament instability is now emerging as the primary cause of revision in the short termKnee instability is multifactorial in originand caused by ligament laxitycomponent alignmentand poor muscle controlWhile there are several reliable systems for accurate component alignmentligament balancing remains an art and is largely dependent on the surgeon s intuition and subjectivefeelXpandOrtho has developed an electronic knee ligament balancing system that measures dynamic balance during knee arthroplasty and addresses many of the major deficiencies in the current standards for optimizing soft tissue balanceThis Phase I SBIR has two aimsIn Aimwe will establish the accuracy of the device in measuring ligament balance while performing knee arthroplasty in cadaver kneesand after changing bone cuts and conducting ligament releasesIn Aimwe will conduct a pilot clinical study for proof of concept assessment of feasibilitysurgeon acceptance and learning curveand short term clinical outcomesThis innovative device is a self contained disposable electronic balancing system with adaptive distractionUnlike traditional mechanical instrumentsour device measures balance over the entire range of flexionThe clinical relevance is in the ability to relate intraoperative balance with postoperative outcometo gain insights intooptimalbalance for kneesthe potential to develop new recommendations for balancingand finally closing the gaps between implant designsurgical alignmentand soft tissue balance for optimizing functionXpandOrthoInc was founded inby DrsColwell and D Lima who have overdecades of experience in knee arthroplastymulticenter clinical trialsand biomechanics researchThe team successfully executed challenging projects such as implantation of electronic knee componentsXpandOrtho has access to surgeons and patients at Scripps Clinicand to their state of the art biomechanics laboratoryXpandOrtho receivedkFDA approval for their first deviceThe broad interest in this device from surgeons and industry in reflected in attached representative letters of interestIn a subsequent Phase II we plan to quantify potential links between intraoperative balance with postoperative outcomes and function Ligament instability after knee arthroplasty is one of the primary causes of revision in the short termThis Phase I SBIR will measure the accuracy of a novel electronic ligament balancing device and demonstrate proof of concept in a pilot clinical studyThe device can relate intraoperative balance with postoperative outcomedevelop new recommendations for balancingand integrate implant designsurgical alignmentand soft tissue balance for optimizing function