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Novel Design of an Anterior Cruciate Ligament (ACL) Injury Prevention Brace. Lawrence Technological University BME Senior Projects 1 Dr. Mansoor Nasir, Fall 2013 Faculty Advisor: Dr. Eric Meyer, PhD Technical Advisor: Ken Cook, P.E. Rachel Porter Dan Greenshields Justin Killewald. - PowerPoint PPT Presentation
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1
Novel Design of an Anterior Cruciate Ligament (ACL) Injury Prevention BraceRachel Porter
Dan Greenshields
Justin Killewald
Lawrence Technological UniversityBME Senior Projects 1Dr. Mansoor Nasir, Fall 2013
Faculty Advisor: Dr. Eric Meyer, PhDTechnical Advisor: Ken Cook, P.E.
2Agenda
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
3Problem
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
4Need 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
5Design
ACL braces Prevent hyperextension Prevent valgus bending
Osteoarthritis braces Unicompartmental loading
Include design characteristics of prevention braces
6Knee Anatomy
Bones Ligaments Menisci Cartilage Muscles/tendons
[2] http://www.webmd.com/pain-management/knee-pain/picture-of-the-knee
7Knee Motions
Sagittal Flexion Extension
Coronal/Frontal Valgus bending Varus bending
Axial Internal rotation
External rotation
8Knee Injuries Bone fracture Torn ligament
ACL PCL MCL LCL
Torn meniscus Lateral Medial
Osteoarthritis
[7]
9ACL 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
http://bretcontreras.com/wp-content/uploads/q-angle-men-vs-women.jpg
10ACL 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
11Objective
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
12Current 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
http://www.djoglobal.com/products/donjoy/defiance
13Osteoarthritis 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
14Modified Hinge Design
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
15Modified Hinge Design cont.
Polycentric normal action Compressive loading – flexed action
16Patent Filing Process
http://www.uspto.gov/patents/process/index.jsp
17Current Patent Search
Hundreds of knee brace patents OA brace ACL brace
Individual components patented Hinge - consistent Strap Frame
18Future 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
19Institutional 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
http://www.irbservices.com/irbservices/Choose_IRBS_files/IRBS%20Master%20Logo.png
20Current Testing Techniques
3D motion capture 20 participants Stop-jump landings
With and without brace
Measured Knee flexion angle Ground reaction forces
[5]
21Experimental 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
http://bjsm.bmj.com/content/early/2010/06/16/bjsm.2009.069351/F2.large.jpg
22Cost & 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
23Timeline
Month Milestone
January Assemble first prototype brace and begin human subject testing
February Continue testing prototype and adjust design
March Adjust design and continue testingData analysis
April Data analysis and interpretation
May Prepare final report and presentationFile provisional patent
24Anticipated Challenges
Not a significant decrease in compressive load forces Time restrictions Failed IRB approval Patent filing
25Tasks & 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
26References
[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 39.11 (2009): 937-60. Print.
[2] http://www.webmd.com/pain-management/knee-pain/picture-of-the-knee [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): 300-06. Print. [4] Meyer, Eric G., and Roger C. Haut. "Excessive Compression of the Human Tibio-femoral Joint
Causes ACL Rupture." Journal of Biomechanics 38.11 (2005): 2311-316. 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): 1136-143. Print.
[6] http://www.djoglobal.com/education/patient-education/acl-bracing [7] Majewski, M., H. Susanne, and S. Klaus. "Epidemiology of Athletic Knee Injuries: A 10-year
Study." The Knee 13.3 (2006): 184-88. 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): 3-10. Print.
27Questions?