Trial Outcomes & Findings for Active Versus Passive Motion Device Following Knee Replacement Surgery (NCT NCT02339831)

1153 patients electing to undergo unilateral partial or total knee replacement at the New England Baptist Hospital from 03/2007-12/2010 were screened for participation. Of these patients, 110 elected to participate in the study and were randomized into one of the two study groups.

Active Versus Passive Motion Device Following Knee Replacement Surgery

Quadriceps strength measurements using a hand held dynamometer

Sit-to-Stand test: After one demonstration of the sit-to-stand test, standing up from a seated position without support, two tests were timed and the better value recorded. Patient was asked to sit with back against chair and told to stand up without using any support. Arms were suggested to be folded in front of chest. Time started with recorded said "Go".

Biodex Balance Machine Score. The system consists of a multiaxial standing platform with a maximum tilt of 20 degrees. All participants were tested on level 8, and a balance index was calculated using the time and deviation (in degrees) on the platform relative to a neutral position. The normal range for adults 54-71 is 1.79 - 3.35. Lower values indicate better/greater stability.

Kinesthesia was measured by recording the angle of the flexed knee and documenting how close the patient was able to reproduce the angle with closed eyes. The differences were recorded in degrees using an 8-inch goniometer.

Knee-flexion was measured using an 8-inch goniometer.

Short form 36 mental health score. The scale is measured from 0-100. 0 is the lowest or worst possible level of functioning and 100 is the highest or best possible level of functioning.

Western Ontario and McMaster Universities Arthritis Index is measured on a scale of 0-68. Higher scores on the WOMAC indicate worse pain, stiffness, and functional limitations.

Knee society score is an objective patient reported outcome survey to measure a patient's functional ability before and after knee arthroplasty. It is measured on a scale of 1-100. A score between 80-100 indicated excellent functioning, a score between 70-79 indicates good functioning, a score between 60-69 indicates fair functioning, and a score below 60 indicates poor functioning.

Self-reported total pain medication consumption was recorded by patients and at the end of the four-week period converted into standard units for comparison as "oxycodone equivalent dosage".