View Full Version : Summary (No. of gait loading cycles/year)

Hassan Serhan
07-18-1995, 08:26 AM
Dear Netters;

My sincerest thanks to all of you who responded to my request for
info on the number of gait loading cycles/year.

my original request was
>Dear Biomch-L readers,

>We are interested in performing statistical analysis of the total number
>of loading cycles per year on the hips and knees of males and females
>during normal daily living. In this study we will include people from
>different age groups and different occupations. We will also include total
>hip and knee arthroplasty patients to measure the pre and post-operative
>activity levels.

>We would like to know if similar work has been done, or if there is another
>research group doing such a work.

>Thank you for any pointers!!

>Hassan A. Serhan PhD
>Asst. Prof. Ortho. Dept.
>SUNY at Buffalo)

================================================== ================
Here is a summary of the information I received:
================================================== ================

From: Ed Lemaire

Geoff Fernie has done some limb limb counting with
amputees some time ago. He is at the U. of Toronto and/or
Sunntbrook Hospital I think. Sorry but I don't have any more
address info. The Hugh MacMillan Rehabilitation Center in
Toronto would know how to reach him.

Ed Lemaire, MSc
The Rehabilitation Center
Ottawa, Ontario, Canada
613-737-7350 x5592


From: "Ton van den Bogert"

Dear Dr. Hassan,

Several groups are working on activity monitoring
using accelerometry, where accelerometer signals are recorded by a
miniature datalogger (for a day, or a week) and analyzed
afterwards. One of those groups is at the University of Twente
(Netherlands). Contact: Dr. Peter Veltink .
Those techniques are able to recognize certain types of activity,
and also allow counting of the number of cycles.

If you are interested in a more quantitative analysis of the hip
joint, my own research may be relevant for you. I have developed
a method, also using accelerometry, to quantify the magnitude of
loading in the hip (not just the type of activity and the number
of cycles). The instrumentation is more complex, however, so
it's probably not suitable for activity monitoring. I used four
triaxial accelerometers on the upper body. You might be able to
use only two, one mounted at the lower back and one mounted
higher up. This is the absolute minimum for estimation of 3-D
linear and angular acceleration of the upper body.

I can send you a copy of a publication, preferably by E-mail

-- Ton van den Bogert
Human Performance Laboratory
University of Calgary


From: Carol Oatis

I believe work was done at Rancho Los Amigos Hospital, Downey California
and the USC Department of Physical Therapy several years ago on steps per
month in healthy subjects and in people with hip DJD. It may have been a
Masters thesis by Patricia McElvey, back in the seventies. I don't know
if it was ever published . Good luck


From: Ton van den Bogert
To: hassan serhan
Subject: Re: No. of gait loading cycles/year

You wrote:
>In our initial study, we used electronic pedometers to simply count the
>number of steps taken by the patients pre and pos-operatively. This data
>will be used as a measure in the evaluation of THA and TKA.

That is probably a good way to do this if walking is the main
type of activity for your patients, i.e. you don't need to
distinguish between different activities (walking, running,
jumping etc.).

>Ps. yes I'm interested in receiving a PS file of your paper, I think it

I will E-mail the file. But, be aware that my application is
quite unique. Most other applications of accelerometers for
activity monotoring use heuristic, rather than mathematical,
analysis to recognize and count activity cycles.

-- Ton van den Bogert


From: lk1boq74@icineca.cineca.it (Marco Viceconti)

You can find info in "Materisl design analysis of the prosthetic anterion
cruciate ligament", J Biomed Mat Res, 14, 1980, pp: 567-586. I think
mostof the data they report is from:

Grood, E.S.; Noyes, F.R. ==> J bone J surg 58A:8 1976 pp1083 1088.

Hope this will help you


Laboratorio di Tecnologia dei Materiali tel.39-51-6366865
Istituti Ortopedici Rizzoli fax.39-51-6366863
via di barbiano 1/10, 40136 - Bologna, Italy


From: Kim Dwyer

Dear Hassan, I am not aware of any research you might find useful, in
fact I often wonder where exactly the figure "1million cycles/year" comes
from---this is what lots of us who perform wear testing to examine
polyethylene performance in total joint replacements use! Please keep me
updated as your study progresses.
One of our Resident's was interested in the amount of activity a
patient with early rheumatoid arthritis performs on a daily basis. He
provided pedometers for each patient that were about the size of a beeper
and asked the patients to wear them every wakig hour for a month. The
devices had their problems and the patients had their noncompliance
problems but it was useful when averaged over a large enough group. Just
an idea...
Another interesting issue that someone suggested is that not only
should we model the average speed at a particular joint and the
number of cycles, etc., but we are missing te boat if we do not model the
daily 'stumble, fall, etc." Someone said to go by our wear tester and
hit it with a hammer every once in a while. This sounds pretty funny
when you first hear it but over time it starts to make some sense
(usually after you do something clumsy yourself :-D
Good luck....

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~
Kimberly A. Dwyer, M.S. Clinical Mechanics Group
Dwyer@ME.QueensU.Ca Mechanical Engineering
Queen's University, Kingston, Canada
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~