Outcome evaluations of lower extremity joint reconstructions should include
an assessment of patient activity. In vivo wear assessments of total joint
prostheses should be based on a measure of use, not time in situ or a prox
y such as age or gender; however, clinicians lack a simple method to reliab
ly assess the activity of patients with joint replacement. The modern pedom
ter can be a satisfactory means of quantifying the use of lower extremity j
oints. The pedometer, however, requires special effort on the part of the p
hysician or evaluator and the patient. Therefore, we compared the quantitat
ive assessment of walking activity of 100 total joint replacement patients,
as measured with a pedometer, to the UCLA activity score and a simple visu
al analog scale that can easily be employed during a routine office evaluat
ion. Both the UCLA activity rating (P = .002) and the visual analog scale r
ating of the investigator (P = .00001) had a strong correlation with the av
erage steps per day as recorded by the pedometer. There was, however, up to
a 15-fold difference in the average steps per day for individual patients
with the same UCLA score. The visual analog scale as rated by the patients
of their own activity did not have as strong a correlation with the pedomet
er data (P = .08) as did patient age (P = .049). For practical reasons, the
pedometer is probably best reserved for the evaluation of extreme cases of
activity (dr inactivity). This study indicates chat both the UCLA activity
rating and the investigator visual analog scale are valid for routine acti
vity assessment in a clinical setting. Adjustments of the UCLA activity sco
re for the frequency and intensity of activity, as can be done with the inv
estigator visual analog scale, increase the accuracy of the activity rating
.