Human KneeJoint Mechanics Module Development

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Human Knee-Joint Mechanics Module Development

• Dr. Robert Freeman
• Ms. Julie L. Fife
• University of Texas - Pan American
• Biomechanics
• June 18th, 2003
• Computer Simulations Also
• Being Demonstrated

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Project Goals

• To investigate a number of distinct theoretical
  sagittal plane models of the human knee joint
• Tibiofemoral Joint Variants
• Simple hinge joint model
• Cruciate linkage model
• Single-point surface contact model
• Patellofemoral Joint Variants
• Single-point patella model
• Rigid-body patella model

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Cruciate Linkage Model
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Cruciate Linkage Model with Single-Point Patella
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Working Model 2D Version of Cruciate Linkage Model

•  

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Knee-Joint Module

• A simulation of the preceding model is run from
  zero degrees flexion to 140 degrees flexion and
  stored as the avi file Knee.avi
• The resulting positional data is stored in the
  Excel file ACLForceData.xls
• Assumptions
• There is no friction between the femoral condyles
  and the (flat) tibial plateau.

The maximum force that the ACL can withstand is
2000N.
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Knee-Joint Module (cont.)

• The patellar tendon force (in Newtons) is given
  below as the fifth order polynomial in the
  flexion angle ? (in degrees).
• This polynomial was obtained as an approximation
  of the results given in Figure 6 of Serpas, et.al.

T(?) 439.106 (305.71?1) (-18.185?2)
(0.554?3) (-6.674 x 10-3?4) (2.5x10-5?5)

• Challenge Question
• Can voluntary contraction of the quadriceps
  muscle group tear the ACL during an isometric
  knee-tension exercise?

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Surface Contact Model
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Associated Instant Center Tutorials
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Other Activity Elbow Joint Module
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Additional Activities at UTPA

• A Planar Biomechanical Model-Based Control of a
  Human Leg
• To develop students understanding of the
  neuromuscular skeletal system from a control
  systems perspective using a simplified computer
  model of the human leg
• Dr. Mounir Ben Ghalia, Electrical Engineering
• Aerobic, Anaerobic, and Muscle Work Capacity
  Development and Retention Models
• To learn the concepts of energy expenditures
  during muscle work through aerobic and anaerobic
  combustion of nutrients as individual and
  combined sources of energy, and the physiological
  changes that take place during the use of muscles
• To learn the concepts of maximum work capacity
  for parts of the body that are generally used to
  perform static work
• Dr. Miguel A. Gonzalez, Manufacturing Engineering
  (Ergonomics)
• Materials Selection for Biological Systems
• To promote students understanding of the complex
  issues surrounding the application of engineering
  materials to biological systems
• To present a motivating challenge for the
  selection of materials for tissue repair in an
  alien creature with an extreme biology
• Dr. Robert Jones, Mechanical Engineering, and Dr.
  Mauli Agrawal (UTHSC-SA).

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Planned UTPA Course Offering

• A new technical elective in Mechanical
  Engineering on Biomechanics in Spring 2004 using
  VaNTH modules.
• Based on materials developed by Drs. Barr
  (UT-Austin), Freeman (UTPA), Pandy (UT-Austin),
  and Roselli (VU).
• Expected Annual Impact
• 30 to 40 Students
• 80 to 85 Hispanic
• 15 to 20 Female