Novel Design of an Anterior Cruciate Ligament (ACL) Injury Prevention Brace Rachel Porter Dan Greenshields Justin Killewald 1 Lawrence Technological University BME Senior Projects 1 Dr. Mansoor Nasir, Fall 2013 Faculty Advisor: Dr. Eric Meyer, PhD Technical Advisor: Ken Cook, P.E.

Agenda  Problem  Need Statement  Background  Knee Anatomy  Knee Mechanics  Knee Injuries  ACL Injuries  ACL Injury Mechanisms  Objective  Current progress/Future plans  Research plan  Design Process  Patent  Testing  Cost & materials  Timeline  Tasks & responsibilities 2

Problem  Knee injuries account for approximately 60% of all sports related injuries. Nearly half of those injuries occur to the ACL [1].  Extensive recovery time ~ 8-12 months 3

Need Statement  An improved knee brace for ACL injury prevention could help lower the injury rate in athletes.  Short term benefits  In turn, this potentially could delay the onset of further knee complications later in life.  Long term benefits 4

Design  ACL braces  Prevent hyperextension  Prevent valgus bending  Osteoarthritis braces  Unicompartmental loading  Include design characteristics of prevention braces 5

Knee Anatomy  Bones  Ligaments  Menisci  Cartilage  Muscles/tendons 6 [2]

Knee Motions  Sagittal  Flexion  Extension  Coronal/Frontal  Valgus bending  Varus bending  Axial  Internal rotation  External rotation 7

Knee Injuries  Bone fracture  Torn ligament  ACL  PCL  MCL  LCL  Torn meniscus  Lateral  Medial  Osteoarthritis 8 [7]

ACL Injuries  200,000 – 300,000 ACL injuries/year in the U.S. [3]  70% of injuries are non-contact [4]  Females are 3-10 times more likely to sustain injury [5]  Stop-jump landing and cutting [5]  Most common injury position: < 30° of flexion 9

ACL Injury Mechanisms  Internal rotation  Foot planted as body twists  Anterior shear of tibia  Foot planted as knee is hit from the front  Axial Load  Compressive force causes tibial slipping (5500 N) [4]  Hyperextension  Tension on ACL causes tearing  Valgus bending  Knee is angled towards center of body 10

Objective  Redesign OA brace hinge to prevent hyperextension, valgus bending, and axial loading on the knee joint to protect the ACL  Research plan  Hinge design  Patent filing  Human subject testing 11

Current ACL Braces  Donjoy Defiance – clinically proven brace  Decreases ACL strain [6]  FourcePoint hinge  Protects against hyperextension and valgus bending  Worn by many college and NFL linemen 12

Osteoarthritis Braces  Commonly used by elderly population  Medial compartment most affected by OA. [8]  Offload medial compartment to even the distribution on compartments  Unicompartmental loading  Medial/lateral 13

Modified Hinge Design 14  Polycentric gears  Spider gears  Hypothesis  Lateral hinge = polycentric  Medial hinge = spider gear  Stainless Steel  Both hinges – prevent hyperextension  Medial hinge – shifts loading mechanism  Lateral hinge – prevent valgus bending

Modified Hinge Design cont.  Polycentric normal action  Compressive loading – flexed action 15

Patent Filing Process 16

Current Patent Search  Hundreds of knee brace patents  OA brace  ACL brace  Individual components patented  Hinge - consistent  Strap  Frame 17

Future Patent Filing  Our design has not been patented  Two different hinges on our brace  Start process in January  Finish and file in May  Could take years to get full patent approval 18

Institutional Review Board (IRB)  Department of Health and Human Services  Protect the rights and welfare of human subjects  Monitor research development, testing and evaluation methods  Submitted for IRB approval  Application  Consent form  Participant info sheet 19

Current Testing Techniques  3D motion capture  20 participants  Stop-jump landings  With and without brace  Measured  Knee flexion angle  Ground reaction forces 20 [5]

Experimental Method  2 participants  Jump landing trials onto force plates  3 tests  Without brace  With Donjoy Defiance brace  With redesigned brace  Measure  Ground reaction force  Segment acceleration  Joint reaction force  Moment  Materials  Vicon Nexus  Polygon 21

Cost & Materials  Braces = $1000  Donjoy OA Defiance Brace  1 male and 1 female  Hinge redesign material = $500  Springs, screws, washers, stainless steel  Testing supplies = $300  Velcro, double sided tape  LESA foundation - $1000 granted 22

Timeline MonthMilestone JanuaryAssemble first prototype brace and begin human subject testing FebruaryContinue testing prototype and adjust design MarchAdjust design and continue testing Data analysis AprilData analysis and interpretation MayPrepare final report and presentation File provisional patent 23

Anticipated Challenges  Not a significant decrease in compressive load forces  Time restrictions  Failed IRB approval  Patent filing 24

Tasks & Responsibilities  Individual tasks  Rachel Porter  Institutional Review Board (IRB) filing  Dan Greenshields  Existing knee brace patent search  Patent application  Justin Killewald  Hinge design research  Materials used in braces  Shared tasks  Prototype design & fabrication  Testing  Data analysis  Presentation creation  Final report documentation 25

References  [1] Rishiraj, Neetu, Jack E. Taunton, Robert Lloyd-Smith, Robert Woollard, William Regan, and D.B. Clement. "The Potential Role of Prophylactic/Functional Knee Bracing in Preventing Knee Ligament Injury." Sports Medicine (2009): Print.  [2] [2]  [3]Teng, Phillis S.P., K.F. Leong, P.Y. Huang, and J. McLaren. "The Effect of a Knee-ankle Restraint on ACL Injury Risk Reduction during Jump-landing." Procedia Engineering60 (2013): Print.  [4] Meyer, Eric G., and Roger C. Haut. "Excessive Compression of the Human Tibio-femoral Joint Causes ACL Rupture." Journal of Biomechanics (2005): Print.  [5] Yu, B. "Immediate Effects of a Knee Brace With a Constraint to Knee Extension on Knee Kinematics and Ground Reaction Forces in a Stop-Jump Task." American Journal of Sports Medicine 32.5 (2004): Print.  [6]  [7] Majewski, M., H. Susanne, and S. Klaus. "Epidemiology of Athletic Knee Injuries: A 10-year Study." The Knee 13.3 (2006): Print.  [8] Gaasbeek, Robert D.A., Brenda E. Groen, Brieke Hampsink, Ronald J. Van Heerwaarden, and Jacques Duysens. "Valgus Bracing in Patients with Medial Compartment Osteoarthritis of the Knee A Gait Analysis Study of a New Brace." Gait & Posture26 (2007): Print. 26

Questions? 27