必ず遭遇する手根管症候群—見分け方と治療法は？

Carpal Tunnel Syndrome:Diagnosis and Treatment

Point

・手根管症候群の症状は，第1〜4指橈側のしびれ，夜間〜早朝にかけての増悪，ring finger splittingが特徴的である．

・診断は，臨床症状とPhalenテストやTinel様徴候などの身体所見，電気生理検査を組み合わせて行う．

・手術療法は有用であり，局所麻酔下に顕微鏡を用いて低侵襲に行える．

　Carpal tunnel syndrome（CTS）is a common entrapment neuropathy caused by compression of the median nerve around the wrist. The risk factors of CTS include female sex, diabetes mellitus, hypothyroidism, obesity, arthritis, hemodialysis, acromegaly, and pregnancy. CTS is characterized by paresthesia in the distribution of the median nerve. Patients are often unaware of ring-finger splitting and the combination of Tinel's sign and Phalen's test improves diagnostic accuracy. In addition, electrophysiological assessments can help to confirm a CTS diagnosis; their sensitivity ranges from 57-94% and their specificity from 51-97%. CTS negatively affects the quality of life but improvement by surgery can be expected. For conservative treatment, a neutral wrist splint worn at night or oral medication such as nonsteroidal anti-inflammatory drugs, vitamin B12, and pregabalin have been shown to be effective against CTS. CTS surgery may be indicated in patients with thenar muscle atrophy and when conservative treatment is ineffective. The surgery involves a small skin incision under a microscope and local anesthesia. Long-term outcomes with respect to pain, numbness, function, symptomatology relapse, and frequency of re-surgery do not significantly differ between patients subjected to open or endoscopic surgery.