• An, Kai-Nan (PI)
  • An, Kai-Nan (PI)

Project: Research project

Project Details


The long-term goal of this study is to address the problems of
elbow joint dysfunction and reconstructive surgery.
Biomechanically, it is important to characterize 1) the mechanical
environment and requirements imposed on the elbow joint in daily
and recreational activities, and 2) the pathologic motion loss,
weakness, and instability, thereby defining the functional
impairment to be corrected or addressed by reconstructive surgery.
A detailed analysis of the reconstructed elbow joint under these
mechanical environments will allow definition of the objective
benefits of the surgery and provide a basis for selecting a given
procedure. The specific aims of this study are: (1) to analyze
the muscle and joint forces across the elbow joint resulting from
selected activities of daily living and (2) to compare the
constraint and stability of five types of prostheses for elbow
joint replacement. To achieve these two specific goals, both the
analytic and experimental methods developed in past years will be
used. The kinematics and external load application on the segments distal
to the elbow joint will be collected for 10 selected activities by
combined use of the electromagnetic tracking system,
electrogoniometers, and load cells. The intersegmental forces and
moments about the elbow joint due to inertial effects as well as
external loading will be calculated using the three-dimensional
DYNAMIC model developed. Finally, the specific muscle and joint
resultant forces and moments will be calculated using the MUSCLE
model. This study will be accomplished by using 40 normal
subjects, 20 of each sex ranging in age from 50-60 years. Joint constraint and stability performance will be used to compare
the five selected designs of prostheses for elbow joint
reconstruction and replacement, each of which is currently
available and represents a unique design feature and concept.
Experimentally, the joint stability or laxity in cadaveric
specimens with prosthetic replacements will be quantitated by using
the joint kinematic analysis. Movement of the elbow joint will be
achieved with simulated muscle loading as well as additional
valgus-varus stress. Changes in the pattern and magnitude of the
axes of rotation will be used to assess the joint constraint. In
addition, the mechanical advantage of each muscle around the
replaced joint will be calculated based on the tendon excursion and
joint rotation. Sensitivity analysis will also be performed to
analyze the effects of surgical placement of these prostheses and
soft tissue reconstruction.
Effective start/end date12/1/7911/30/98


  • National Institutes of Health
  • National Institutes of Health: $152,427.00
  • National Institutes of Health
  • National Institutes of Health: $133,366.00
  • National Institutes of Health
  • National Institutes of Health
  • National Institutes of Health
  • National Institutes of Health
  • National Institutes of Health


  • Medicine(all)


Explore the research topics touched on by this project. These labels are generated based on the underlying awards/grants. Together they form a unique fingerprint.