Prefrontal versus motor cortex transcranial direct current stimulation (tDCS) effects on post-surgical opioid use

Area of Science:

• Neurosurgery
• Pain Management
• Neuromodulation

Background:

• Post-operative pain is a significant concern following total knee arthroplasty (TKA).
• Previous research indicated opioid-sparing effects of motor cortex transcranial direct current stimulation (tDCS).
• This study aimed to compare motor cortex tDCS and prefrontal cortex tDCS against sham and active controls.

Purpose of the Study:

• To evaluate the efficacy of prefrontal cortex and motor cortex tDCS in reducing post-operative opioid consumption after TKA.
• To compare the effects of targeted tDCS interventions with sham and active control groups.

Main Methods:

• 58 patients undergoing unilateral TKA were randomized into four groups: motor cortex tDCS, prefrontal cortex tDCS, active control, and sham.
• Patients received four 20-minute sessions of tDCS (2 mA) post-surgery.
• Opioid consumption (hydromorphone via patient-controlled analgesia) was monitored for approximately 72 hours.

Main Results:

• The prefrontal cortex tDCS group showed significantly lower hydromorphone use compared to the sham group (p < 0.0001).
• The motor cortex tDCS group exhibited significantly higher hydromorphone use than the sham group (p < 0.0001).
• No significant difference in opioid use was observed between the sham and active-control groups.

Conclusions:

• Anodal tDCS over the left prefrontal cortex appears to be a promising strategy for reducing opioid requirements after TKA.
• Motor cortex stimulation did not yield opioid-sparing effects in this double-blind study.
• Further research is warranted to optimize cortical stimulation techniques for post-operative pain management.