Biomedical Engineering Reference
In-Depth Information
FIGURE 10-16
The Aulie 802 is a
typical passive
prosthetic knee joint
shown here
extended and flexed.
(Courtesy of Aulie,
with permission.)
FIGURE 10-17
Low-cost knee prostheses (a) Comparison between the JaipurKnee and
the LEGS M1. (b) JaipurKnee in action. (Courtesy of LeTourneau University and Melanie
Worley, Re:Motion Designs, with permission.)
The JaipurKnee shown in Figure 10-17, was developed by biomedical device design
and evaluation students at Stanford University based on their examination of the mechan-
ics of high-end titanium knee joints costing between $10,000 and $100,000. They also
surveyed a range of materials to find one that would be suitable to build a cheap pros-
thetic. The JaipurKnee is a polycentric knee joint made from oil-filled nylon polymer that
is self-lubricating and can be manufactured for under US$20 (Greig, 2009).
Prior to this, starting in 2004 students at LeTourneau University in Texas were develop-
ing the LeTourneau Engineering Global Solutions (LEGS) M1 knee. It is a block-shaped,
four-bar, polycentric joint made from Delrin, a low-cost polymer used to make journal
bearings and stainless steel bolts. The M1 costs about $15 to make and is being locally
manufactured at some of the 20 prosthetics clinics in developing nations (Stanfield, 2010).
