The purpose of this study is to evaluate the effect of the KneeMD subject-controlled knee rehabilitation device on the incidence of postoperative flexion contracture.

Postoperative flexion contracture (FC), defined as >10°, is the most common disabling early complication of primary total knee replacement (TKR) surgery, affecting up to 6% of all subjects. A knee flexion of 65° is required to walk, 70° is needed to lift an object from the floor, 85° to climb stairs, 95° for optimal sitting and standing, and 105° to tie shoelaces. With growing subject and physician expectations for function and range of motion (ROM) after surgery, FC complications have become an early measure of success in TKR surgery.

The purpose of this study is to evaluate the effect of the KneeMD subject-controlled knee rehabilitation device on the incidence of postoperative FC. The primary endpoints are the preoperative change in active range of motion (AROM) and the incidence of postoperative FC at 2 weeks. Secondary endpoints include the change in AROM in subjects with postoperative FC.

Inclusion Criteria:

1. Measurable Knee Flexion Contracture, with deficit limiting Active Range of Motion (AROM) and Passive Range of Motion (PROM) by at least - 10°
2. 18 years of age and older
3. Able to understand informed consent and willingness to conform to trial responsibilities

Exclusion Criteria:

1. Previous surgical treatment of knee, including tibial osteotomy
2. Botulinum Toxin Treatment within the last four months
3. Mechanical joint impingement
4. Neuromuscular pathologies such as epilepsy
5. Treatment with quinolone, antibiotic medication
6. Pregnant or nursing
7. Fractures
8. Osteomyelitis or any orthopedic infection
9. Extensor mechanism dysfunction
10. Knee joint neuropathy
11. Previous Stroke or Brain Injury