Effects of Transcranial Direct Current Stimulation on Pain Control in Chronic Painful Total Knee Arthroplasty

The TSEF-PTG study is a single center, double blinded randomized controlled trial.

The aim is to evaluate the effects of a tDCS stimulation and exercise vs sham tDCS and exercise on pain control in chronic (lasting more than 3 months from the intervention) painful total knee arthroplasty (TKA) patients.

The participants will be randomized in two groups: intervention group (IG) and control group (CG).

The IG will receive a 20 minute program of active tDCS (2mA intensity, anode placed on primary motor cortex controlateral to the TKA, cathode placed on controlateral supraorbital region) followed by a 30 minute exercise program, 5 days a week, for 2 consecutive weeks.

The CG will receive a 20 minute program of sham tDCS (15 seconds of activation and then no stimulation, same position of IG) followed by the same 30 minute exercise program, 5 days a week, for 2 consecutive weeks.

The participants will be evaluated at T0 (enrolling), T1 (at the end of the program), T2 (at 1 month from the end of the program) and T3 (at 3 months from the end of the program).

The primary outcome is the variation of pain intensity, the secondary outcomes are the variation of knee function and of the quality of life.

Inclusion criteria

• signed informed consent
• able to independently walk (with or without walk aids)
• chronic painful TKA (more than 3 months)
• Visual Analogic Scale for pain more than 3/10
• No cognitive impairments (MMSE>24 or =24/30)

Exclusion criteria

• intracranial metal devices, pacemakers or any implantable devices
• cutaneous abnormalities on the stimulation sites
• epilepsy (past or present)
• neurological or psychiatric pathologies
• cognitive impairment (MMSE<24/30)
• no opioids abuse (past or present)
• severe cardiopulmonary, renal or hepatic pathologies
• pregnancy
• known present TKA complications (e.g. infections, mobilization, etc...)
• pain therapy modifications in the last 1 month