Article

The aims of this study were to evaluate weight bearing during standing
and 30- and 60-degree squats approximately 1 wk and 2 mos after surgery and
determine whether weight bearing during squatting could be a better clinical
marker than standing for identifying perceived functional limitation
approximately 1 wk after surgery. A further objective was to determine whether
age, body mass index, and number of outpatient visits over the course of
rehabilitation predicted weight bearing during a squat approximately 2 mos after
surgery. DESIGN: The percentage of body weight placed over both limbs during
stand and 30- and 60-degree squats in 38 patients (25 women and 13 men) who had
primary unilateral knee arthroplasty was determined. An asymmetry index would be
used as a marker that could discriminate between those who perceived at least
moderate difficulty with functional tasks and those who perceived only slight or
no difficulty with functional activities based on the physical function dimension
of the Western Ontario McMaster Universities Osteoarthritis index approximately 1
wk after surgery. Stepwise regression was conducted to determine whether clinical
characteristics predicted weight-bearing asymmetry at discharge. RESULTS: At
initial visit (first observation), and compared with the uninvolved side,
individuals placed significantly less body weight over the involved or operated
limb for stand and 30- and 60-degree squats (P < 0.0001). Results were similar at
last rehabilitation visit (second observation). Identifying at least moderate
self-reported difficulty with functional tasks based on the receiver operator
characteristic curve for the asymmetry index for the stand position was 0.64,
whereas for the 30- and 60-degree squats, the area under the curve was 0.81 and
0.89, respectively. At discharge from rehabilitation, there was a moderate to
good direct relationship (r = 0.70) between the number of rehabilitation visits
completed and the weight-bearing asymmetry index for the 60-degree squat.
CONCLUSIONS: On the first outpatient visit, individuals who had primary
unilateral knee arthroplasty placed more body weight over the uninvolved side for
the three weight-bearing positions. With high probability, the asymmetry index
for both squatting angles identified perceived functional difficulty. As
rehabilitation visits increased, there was a direct association to improved
interlimb weight-bearing symmetry when squatting to 60 degrees.

Langue : ANGLAIS