New in the Literature: Squatting as a Clinical Marker of Function After Total Knee Arthroplasty (Am J Phys Med Rehabil. 2013;92(1):53-60.)
In
patients who have primary unilateral knee arthroplasty, as rehabilitation
visits increased there was a direct association to improved interlimb
weight-bearing symmetry when squatting to 60 degrees, say authors of an article in American Journal of Physical Medicine &
Rehabilitation.
For this study, 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 was
used as a marker that could discriminate between patients 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 week after surgery. Stepwise regression was conducted to
determine whether clinical characteristics predicted weight-bearing asymmetry
at discharge.
At initial visit (first observation), 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. 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.
APTA member Mark D. Rossi, PT,
PhD, CSCS, is the article's lead
author. APTA members Thomas Eberle, PT, DPT, DMT, FAAOMPT, Denis
Brunt, PT, EdD, Marlon Wong, PT, DPT, OCS, MTC, and Matthew Waggoner,
PT, DPT, MTC, are coauthors.