The Effectiveness of Virtual Reality Based Rehabilitation in Patients With Knee Osteoarthritis

PEDALO® Sensamove Balance System was used to evaluate postural balance of subjects.It has a balance board in which consists of sensors to record and process data about balance performance to a computer.

Severity of the knee Osteoarthritis of participants was evaulated with "Western Ontario and McMaster Universities Arthritis" (WOMAC LK 3.1). The WOMAC LK has 24 questions in three subscales (pain , stiffness, physical functions) and a total of 24 questions. Each item is scored 0 to 4. Maxiumum score is 96. the higher the scores indicate that the severity of the disease is worse.

Kinesiophobia was assessed with TAMPA Scale for Kinesiophobia (TSK). TSK is a 17-item measure that assesses kinesiophobia (fear of movement). Each item is evaluated on a 4-point Likert scale with scoring alternatives ranging from 'strongly disagree' to 'strongly agree. Total scores range from 17 to 68, with higher scores reflecting greater kinesiophobia.

Muscle Strength was evaulated with Biodex System Pro 4 Isokinetic Dynamometer (Biodex Medical Systems, Inc, Shirley, NY. USA). The subjects were seated in such a position that knee and hip were at 900 flexion, and shoulders, ankle and pelvis were fixed to the machine. The centre of the knee joint was aligned with the centre of the dynamometer by using a laser-pointing device. Before testing, 5-min warming programme was performed by using treadmill. Isokinetic test was performed with 5 repetitions at 1200/s and 2400/s angular velocities. Tests were performed in a standardized order and all subjects have received identical instructions and encouragements.

Pain was evaulated with VAS (Visual Analog Scale). The VAS consists of a 10 cm straight line which presents a continuum of intensity and has verbal anchors at opposite ends representing 'no pain' at the bottom and 'pain as bad as it can be' at the top. The participants were asked to mark the representing point of their pain levels. The values were recorded in cm .

Knee proprioception was evaulated with MarVAJED system (Marmara Visual Auditory Joint Education Device). MarVAJED® is used in virtual rehabilitation and also has test software which can evaluate knee proprioception. The sensors of the system were placed on the upper and lower parts of the knee joint. The subjects were asked to lie down in prone position. The system was calibrated and then the knee joint was passively flexed at 30 degree. Participants were allowed to wait for ten minutes in this position to perceive the degree of knee flexion. Then the knee joint was passively brought back to the initial position and the patients were asked to actively flex their knee at 300 with their eyes closed. The same protocol was performed in 60 degree. . The difference between the reference degree and the degree that the subject performed during the test was automatically calculated by the MarVAJED system.

The active range of motion of knee (flexion, extension) was assessed by using a universal goniometer. Kendall-McCreary criteria was considered in the assessments. Measurements were repeated three times and the average value was used in the statistical analysis.

Functionality of participants was evaulated with Aggregated Locomotor Function (ALF) test. Aggregated Locomotor Function (ALF) test consists of three parts: stair climbing, walk and transfer tests. The time was recorded for each of the tests. longer periods mean that functionality is worse.