Carpal tunnel syndrome (CTS) is a common entrapment neuropathy of the median nerve characterized by paresthesias and pain in the first through fourth digits. We hypothesize that aberrant afferent input from CTS will lead to maladaptive cortical plasticity, which may be corrected by appropriate therapy. Functional MRI (fMRI) scanning and clinical testing was performed on CTS patients at baseline and after 5 weeks of acupuncture treatment. As a control, healthy adults were also tested 5 weeks apart.
During fMRI, sensory stimulation was performed for median nerve innervated digit 2 (D2) and digit 3 (D3), and ulnar nerve innervated digit 5 (D5). Surface-based and region of interest (ROI)-based analyses demonstrated that while the extent of fMRI activity in contralateral Brodmann Area 1 (BA 1) and BA 4 was increased in CTS compared to healthy adults, after acupuncture there was a significant decrease in contralateral BA 1 (P