Knee Osteoarthritis in elder cause pain and decrease their functional activity. After conservative rehabilitation failure, they might receive total knee arthroplasty. The post-operation rehabilitation could improve range of motion and might help them to back activities of daily Living earlier. However, the pain and swelling after the operation of total knee arthroplasty cause the limitation of early mobilization, cause ROM limitation, muscle strength decrease, functional activity decrease, and impaired activity of daily life. In recent studies, the effect of whole body vibration included improving pain, swelling, muscle strength, balance, and functional activity, increasing metabolic rate and decreasing lactate accumulation. the investigators expect the early intervention of whole body vibration and traditional physical therapy on the post-TKA patient could improve ROM, decrease swelling, increased muscle strength, functional activity, and balance as compared with traditional physical therapy.

1. Name: whole body vibration BW-750
2. Dosage form: frequency 4-10 Hz, 10-15minutes with rest for 3-5 minutes * 2 days in standing position
3. Dose(s): post-op day2, WBV 4-10 Hz, 10-15minutes with rest for 3-5 minutes, post-op day3 WBV 4-10 Hz, 10-15 minutes with 3-5 minutes in standing position
4. Dosing schedule: whole body vibration 4-10 Hz for 10-15 minutes with rest 3-5 minutes on post-op day 2 and day3
5. Mechanism of action: passive muscle contraction, improve swelling, increase blood flow, and improve muscle strength
6. Pharmacological category: N/A

IV.Study design 1. ■ Control: ■ placebo 2. Blinding: ■ double blind 3. Randomized: ■ yes □ no 4. ■ Parallel 5. Duration of study:from IRB approval ~to 31 , Dec. , 2019 6. Number of subjects: 52 persons 7. Is there any of the followings included DSMB, Data Safety Monitoring Board:

• no V.Assessment criteria 1. Efficacy: pain (VAS)，swelling circumference，knee range of motion，knee extensor muscle strength，time up and go，and Activities of Daily Living 2. Safety: The duration and frequency of whole body vibration is relative low. The risk of damage is very low 3. Pharmacokinetics: Not apply 4. Quality of life: Through facilitate muscle contraction, improve blood flow, and decrease pain could improve muscle power, increase range of motion and ADL VI. Selection criteria

  1. Main inclusion criteria: knee osteoarthritis, post-operation of total knee arthroplasty, single leg
  2. Main exclusion criteria: vital signs unstable, uncontrolled blood pressure, diabetes mellitus, neoplasm, neurological disorder, fibromyalgia, cardiac pacemaker, bilateral TKA, musculoskeletal involvement other than TKA VII.Study procedures(summary)
  1. Written informed consent must be obtained before any study specific procedures are undertaken.
  2. The process of the experiment (brief describe)

  1. Randomized distribute participants into two groups, "whole body vibration(experimental group)+ traditional physical therapy" group and "placebo group with traditional physical therapy+ whole body vibration (placebo without turn-on vibration)".

  2. Post-TKA day 1 (not op day) Pre-test (baselin data) include pain(VAS), leg circumference, knee ROM, knee extensor strength (JAMMAR), sit to stand average duration, 6 meters ambulatory test.

     Both groups receive traditional physical therapy and passive continuous passive motion (CPM).

  3. Post-TKA day 2 Both groups keep traditional physical therapy and CPM.

  (1) The experimental group perform pre-test before the treatment. After the pre-test, participants receive 10-15 minutes WBV exercise in standing position, amplitude 2mm, frequency 4-10Hz, with rest about 3-5minutes. After the treatment, perform post-treatment test 1.

  (2) The control group standing on the WBV machine without turn-on for 10-15 minutes and then post-treatment test 1.

  4. Post-TKA day 3

  1. The experimental group participants receive 10-15 minutes WBV exercise in standing position, amplitude 2mm, frequency 4-10 Hz, with rest about 3-5minutes. After the treatment, perform post-treatment test 2.

  2. The control group standing on the WBV machine without turn-on for 10-15 minutes and then post-treatment test 1.

     Statistical analysis 1. Statistical Method for Efficacy / Safety measurements: Demographic data were collected on age, pre-TKA Osteoarthritis X-ray Kellgren-Lawrence classification, sex, weight, height, side of involvement. The investigators use t-test, or chi-square test to confirm homogeneity.

     On the other side, measurement the circulation of the affected limb above knee 15 cm, knee and below knee 5cm for swelling evaluation. Pain scale with Numeric Rating Scale; NRS) before intervention, post-test 1 and post-test 2. Muscle power of knee extensor by the duration with holding knee extension in sitting position before intervention, post-test 1 and post-test 2 Knee range of motion with goniometer in sitting (prone position) The duration of time up and go，6 meter ambulation test with walker usage. ADL evaluation with Barthel Index including transfer score, ambulation score, and up/down stairs score. Paired t-test is applied for statistical significance between these measurements.

     Discussion The investigator expected that post treatment, the patients in the vibration group got increases in knee extensor strength, improvement in calf swelling and functional performance when compared to the control group.

Inclusion Criteria:

• knee osteoarthritis
• post-operation of total knee arthroplasty
• single leg knee arthroplasty

Exclusion Criteria:

• vital signs unstable
• uncontrolled blood pressure
• diabetes mellitus
• neoplasm
• neurological disorder
• fibromyalgia
• cardiac pacemaker
• musculoskeletal involvement other than TKA

A single-blinded randomized control trial Intervention by the physical therapist Evaluation by the physician