Study Design
People who met the inclusion criteria
were invited to a motion analysis
laboratory for an instrumented gait
analysis. Participants first provided
written informed consent. Next, anatomical
markers were placed over
the following landmarks on the limb
that was diagnosed with knee OA:
the greater trochanters, the medial
and lateral femoral condyles, the
medial and lateral malleoli, the heads
of the first and fifth metatarsals, and
the distal aspect of the laboratory
shoe (Nike Air Pegasus*). Tracking
markers were placed on the skin
over the L5–S1 interspinous space,
the ipsilateral anterior superior iliac
spine, and the ipsilateral iliac crest.
Additionally, clusters of 4 tracking
markers were placed on the distal
posterior thigh and the posterior lateral
shank. A cluster of 3 individual
rear-foot markers were placed
directly over the calcaneus and projected
through holes in the heel
counters of the laboratory shoe.15
Marker placement and testing were
completed by 2 trained laboratory
researchers using a marker set that
has been shown to be reliable within
and between days.18