Knee Arthroplasty Rehabilitation Outcomes Study

The intervention is to ask study participants to ambulate using an anti-gravity treadmill that integrates patented, NASA Differential Air Pressure (DAP) technology -- a precise air calibration system -- to uniformly reduce gravitational load and body weight during the warm-up phase of an outpatient physical therapy following a single total knee replacement.

The intervention is to ask study participants to warm up using Patterned Electrical Neuromuscular Stimulation (PENS) - that closely replicates the body's normal muscle and nerve firing patterns -- on his/her surgical leg in conjunction with a recumbent bike or a Nu-step bike during the warm-up phase of an outpatient physical therapy following a single total knee replacement.

The intervention is to ask study participants to ambulate using an anti-gravity treadmill in conjunction with use of Patterned Electrical Neuromuscular Stimulation (PENS) during the warm-up phase of an outpatient physical therapy following a single total knee replacement.

This is the active comparator of the trial that participants are asked to use either a recumbent or Nu-step bike normally seen in an outpatient physical therapy clinic to warm-up during a physical therapy session following a single total knee replacement.