- neurological, vascular or cardiac problems that limited physical function, contralateral knee pain greater than 2/10 on a numerical pain rating scale, severe osteoarthritis or other orthopaedic conditions in the non-operated lower extremity that limited function, sub-acute inpatient rehabilitation following unilateral total knee arthroplasty, uncontrolled diabetes, smoking or drug abuse, living >45 minutes away from the outpatient rehabilitation clinic, surgical complication requiring an altered course of rehabilitation, inability to walk 30 meters without an assistive device or inability to rise from a chair without use of arms