29. August 2017 · Comments Off · Categories: Acupuncture, Carpal Tunnel Syndrome

Acupuncture may achieve long-term pain relief in carpal tunnel syndrome (CTS) by rewiring the brain, according to findings by an American research team. Previous studies have shown that the brain’s primary somatosensory cortex, which receives incoming signals related to the sense of touch, is pathologically remapped in CTS. Specifically, brain cells that usually respond to touch from specific fingers start to respond to signals from multiple fingers (measured as reduced cortical separation distance). In a sham-controlled neuroimaging study of acupuncture for CTS, researchers divided 80 patients into three groups. One group received electro-acupuncture on the hand and arm near the site of their pain (local), the second received electro-acupuncture on the ankle opposite the wrist with the pain (distal), while the third received sham electro-acupuncture with non-penetrating needles near the site of carpal tunnel pain. Each patient received 16 treatments over two months. At the end of the treatment period, the researchers found that all three interventions improved patient-reported CTS symptoms. However, only verum (local and distal) acupuncture produced improvements in neurophysiological outcomes, both local to the wrist (median sensory nerve conduction speed) and in the brain (cortical separation distance). Local verum acupuncture led to measurable improvements in outcomes both at the affected wrist and in the brain, while distal verum acupuncture produced improvement at the wrist only. Brain remapping seen after local verum acupuncture was correlated with sustained improvements in symptom severity at three-month follow-up. No physiological improvements resulted from sham acupuncture. The authors propose that while sham acupuncture may provide short-term benefits by modulating known placebo circuitry in the brain, real acupuncture can lead to lasting improvement in CTS symptoms by rewiring the primary somatosensory cortex, in addition to modulating local blood flow to the peripheral nerve in the wrist.
Rewiring the primary somatosensory cortex in carpal tunnel syndrome with acupuncture. Brain. 2017 Apr 1;140(4):914-927.

A group from Taiwan has demonstrated that short-term acupuncture treatment can result in long-term improvement in carpal tunnel syndrome (CTS), and that acupuncture produces significantly better results than oral steroid treatment. Seventy-seven patients with mild-to-moderate idiopathic CTS were randomised to either four weeks of oral prednisolone or twice-weekly acupuncture sessions. The patients were followed up at seven and 13 months using global symptom score (GSS) assessments and electrophysiological nerve conduction studies. Compared with baseline levels, the percentages of patients who showed treatment failure, moderate improvement and good improvement were significantly different between the two groups in favour of acupuncture, at both month seven (10.5, 2.6 and 86.8% acupuncture vs 33.3, 7.7, and 59% steroids) and month 13 (15.8, 2.6 and 81.6% acupuncture vs 51.3, 0 and 48.7% steroids). The acupuncture group showed significantly better improvement in GSS, distal motor latencies and distal sensory latencies compared to the steroid group throughout the one-year follow-up period. (A Randomized Clinical Trial of Acupuncture Versus Oral Steroids for Carpal Tunnel Syndrome: A Long-Term Follow-Up. J Pain. 2010 Nov 24. [Epub ahead of print]).

A systematic review and meta-analysis evaluating the effectiveness of acupuncture and acupuncture-like treatments for CTS carried out by Korean authors has concluded that the evidence for acupuncture as a symptomatic therapy for CTS is encouraging, but not convincing. Six RCTs met their inclusion criteria, and a meta-analysis of acupuncture versus steroid injection therapy favoured acupuncture in terms of responder rate. The methodological quality of the reviewed studies was assessed as generally low land the authors called for further rigorous studies to establish the therapeutic value of acupuncture for this condition. (Acupuncture for Carpal Tunnel Syndrome: A Systematic Review of Randomized Controlled Trials. J Pain. 2010 Nov 17. [Epub ahead of print]).