The Effect of tDCS in the Preoperative Period of Hallux Valgus Surgical Treatment

Hospital de Clinicas de Porto Alegre

Status: Completed

Conditions: Hallux Valgus; Chronic Pain

Treatments: Device: Active tDCS; Device: Sham tDCS

Study type: Interventional

Funder types: Other

Identifiers

NCT02360462

14-0643

Details and patient eligibility

About

This is a clinical trial that intend to determine if transcranial direct current stimulation (tDCS) is effective in the treatment of postoperative pain and in the anxiety level in the preoperative period of hallux valgus surgical treatment

Full description

Introduction: Forefoot deformities are important cause of feet pain and discomfort and affect around 80% of general population, predominantly in female population. Among teenagers and adults´ common forefoot deformities is hallux valgus. To achieve the deformity heal, surgical treatment is needed. The transcranial direct current stimulation (tDCS) is a non invasive technic, that aims for the central nervous system modulation for pain control, which can become a therapeutic option for postoperative pain. Experimental studies have shown that tDCS has reverted the hyperalgesia induced by chronic stress and articular inflammatory pain, has reduced total knee arthroplasty postoperative opioid consumption and a single 20 minutes session has shown reduction in endoscopic procedures opioid consumption, safety and minimal adverse effects. However, the tDCS effect in preoperative hyperalgesia has not been explored yet in sensitized patients, neither in anxiety and postoperative rehabilitation of patients submitted to hallux valgus surgical correction. In this study, it was chosen to use tDCS to stimulate cerebral cortex due to its efficacy in painful syndromes, for being a non invasive, low cost and easy-to-apply technic in comparison to other neurostimulation technics and especially, for its potential to counter-regulate the mal adaptive neuroplastic alterations associated to chronic pain. Objective: to evaluate the effect of tDCS compared to tDCS-sham in the pain control (visual analog scale score, pain threshold and the descendent modulator system), perioperative anxiety, postoperative analgesic drug consumption and in the rehabilitation of patients with arthralgia of the first metatarsophalangeal articulation submitted to hallux valgus surgical correction. Method: it is a randomized, blinded, placebo-sham controlled clinical trial which includes 40 female patients, between 18 and 70 years old, candidates to hallux valgus surgical treatment by combined Chevron + Akin osteotomy due to arthralgia of the first metatarsophalangeal articulation. The patients will be randomized and divided into two groups that will be treated with two tDCS or tDCS-sham sessions of 20 minutes each in preoperative period. Expected results: This study will evaluate the effect of tDCS as a treatment option to postoperative pain and perioperative anxiety of patients submitted to hallux valgus surgical correction. In case of proven efficacy, this technic can become a low cost, easy access, safe and effective treatment option for these patients.

Enrollment: 40 patients

Sex: Female

Ages: 18 to 70 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• indication of hallux valgus surgical treatment because of arthralgia of the first metatarsophalangeal joint,
• capability of writing and understanding the Portuguese language

Exclusion criteria

• diabetic neuropathy,
• history of intense or frequent headache,
• chronic dermatologic disease,
• previous adverse effects to treatment with tDCS, seizures,
• severe cranial trauma with alteration of the cranial anatomy,
• metallic intracranial implants or pacemaker,
• non-compensated psychiatric disease,
• non-collaborative patients,
• history of neurologic,
• oncologic disease,
• heart, renal or hepatic failure.

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

---

40 participants in 2 patient groups

Active tDCS

Experimental group

Description:

Active tDCS will be applied in the head of the patients in 20 minute sessions, twice. First session will be applied in the night before and the second session, in the morning before the surgical procedure. The stimulation will be administered with a pair of surface electrodes, sponge coated, soaked in saline. A battery-powered constant current stimulator will be used for this purpose (tDCS device). The stimulation is performed by placing the anodal electrode in the primary motor cortex (M1) and the cathodal one in the contralateral supraorbital area, and it will use a 2 mA current

Treatment:

Device: Active tDCS

Sham tDCS

Sham Comparator group

Description:

The sham tDCS consists in the same montage of the active tDCS, but the device is turned off 30 seconds after starting stimulation (without letting the patient notice it). The rest of the montage is kept identical to the active one during the 20 minutes session.

Treatment:

Device: Sham tDCS