Transcranial Direct Current Stimulation in Older Persons With Knee Pain (Knee Pain and tDCS): Randomized Pilot Study
Condition: Knee Osteoarthritis
MeSH terms: Osteoarthritis; Osteoarthritis, Knee
Study type: Interventional

Summary: 
      The purpose of this research is to study the effects of Transcranial Direct Current
      Stimulation (tDCS) on clinical pain, mobility disability, and pain sensitivity to gain a
      better understanding of the factors that cause pain and disability in people with knee
      osteoarthritis (OA). In particular, people from different ethnic and racial groups may
      experience OA pain differently which is why the focus will be on older Asian Americans and
      non-Hispanic whites. It is important to find a reason for such difference so that a better
      treatment can be found for all OA patients. In addition, the research study will examine if
      there is any ethnic differences in pain and mobility disability. The investigator hypothesize
      that Asian Americans will report greater pain and mobility disability than non-Hispanic
      whites, and that active tDCS will result in improvement in pain and disability compared to
      sham tDCS.
    

Detailed description: 
      If you participate in the study, the following will happen:

      Randomized into one of two groups. Which will either receive the full length session of brain
      stimulation or a much shorter session of brain stimulation. The shorter version of
      stimulation looks like and is performed in the same way as the longer electrical stimulation
      session, but stimulation is stopped before it can have much of an effect on the brain. You
      will not know which group you have been assigned to while participating in the research, but
      you may find out at the completion of the research study.

      X-Rays will be done on both knees while standing up.

      Questionnaires about arthritis pain you are having, your thoughts and feelings about it, and
      any stress that you may have experienced.

      Walking Test will be performed on a flat surface for 6 minutes at a fast pace without help
      from an assistive device (cane or walker) or another person.

      Assessment of Physical Performance requires walking at short distance (about 13 feet), stand
      up from a chair 5 times without using your arms, and stand in 3 different positions while
      keeping your balance.

      Assessment of Sensitivity to Heat. Heat pain sensitivity will be tested using a commercially
      available thermal sensory testing machine (Medoc, Inc.) used widely in clinical settings.
      This machine has a small (about 1 inch by 1 inch) square piece that is used to apply heat to
      the skin. Heat will be applied to the knees and arms. The amount of heat is controlled by a
      computer. One or more of the following types of heat stimuli will be delivered: 1) a slowly
      increasing heat that can be stopped by pressing a button when it becomes warm, painful, or
      intolerable; 2) a series of 5-10 heat pulses that are brief (less than 2 seconds in
      duration), and rate how painful each heat pulse feels; and 3) a few longer heat pulses (15-30
      seconds) at different temperatures to rate how painful each heat pulse feels. The procedures
      can be stop at any time.

      Assessment of Sensitivity to Pressure will be done using a handheld device with a small
      rubber tip to apply pressure to the knee, thigh, and shoulder.

      Assessment of Sensitivity to Mechanical Stimulation will be done using a handheld probe that
      has a small nylon tip to tap both the knee and hand.

      Blood Draw: Blood will be taken at the baseline visit and at the last visit.

      Brain Stimulation: The stimulation technique called transcranial direct current stimulation
      (tDCS) and it involves placing two sponge-like electrodes on your head and delivering a very
      weak electrical current to your scalp, which is generated by a 9 volt battery.

      In addition, weekly phone calls will be done for the next 3 weeks.
    

Intervention name(s): Active tDCS; Sham tDCS
Intervention type(s): Device; Device
Intervention description(s): This group will receive tDCS with a constant current of 2 mA intensity will be applied for 20 minutes once a day for five consecutive days using a pair of thick (0.3 cm) rectangular surface sponge electrodes (5 cm x 7 cm) saturated with 10 mL of saline solution. The anode electrode will be placed over M1 (C3 or C4 according to the 10-20 system for EEG electrode placement) of the hemisphere contralateral to the affected knee, and the cathode electrode will be placed over the supraorbital region (SO) ipsilateral to the affected knee (M1-SO montage).; This group will receive tDCS with a constant current of 2 mA intensity will be applied for 30 seconds once a day for five consecutive days using a pair of thick (0.3 cm) rectangular surface sponge electrodes (5 cm x 7 cm) saturated with 10 mL of saline solution. The anode electrode will be placed over M1 (C3 or C4 according to the 10-20 system for EEG electrode placement) of the hemisphere contralateral to the affected knee, and the cathode electrode will be placed over the supraorbital region (SO) ipsilateral to the affected knee (M1-SO montage).
Other intervention name(s): Transcranial Direct Current Stimulation
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment