title: Carpal tunnel syndrome treated with a diode laser: a controlled treatment of the transverse carpal ligament.
abstract: OBJECTIVE
  The purpose of this placebo-controlled study was to investigate the therapeutic effects of the 830-nm diode laser on carpal tunnel syndrome (CTS).
  
  
  BACKGROUND
  Many articles in the literature have demonstrated that low-level laser therapy (LLLT) may help to alleviate various types of nerve pain, especially for CTS treatment. We placed an 830-nm laser directly above the transverse carpal ligament, which is between the pisiform and navicular bones of the tested patients, to determine the therapeutic effect of LLLT.
  
  
  METHODS
  Thirty-six patients with mild to moderate degree of CTS were randomly divided into two groups. The laser group received laser treatment (10 Hz, 50% duty cycle, 60 mW, 9.7 J/cm(2), at 830 nm), and the placebo group received sham laser treatment. Both groups received treatment for 2 wk consisting of a 10-min laser irradiation session each day, 5 d a week. The therapeutic effects were assessed on symptoms and functional changes, and with nerve conduction studies (NCS), grip strength assessment, and with a visual analogue scale (VAS), soon after treatment and at 2-wk follow-up.
  
  
  RESULTS
  Before treatment, there were no significant differences between the two groups for all assessments (p > 0.05). The VAS scores were significantly lower in the laser group than the placebo group after treatment and at follow-up (p < 0.05). After 2 wk of treatment, no significant differences were found in grip strengths or for symptoms and functional assessments (p > 0.05). However, there were statistically significant differences in these variables at 2-wk follow-up (p < 0.05). Regarding the findings of NCS, there was no statistically significant difference between groups after treatment and at 2-wk follow-up.
  
  
  CONCLUSIONS
  LLLT was effective in alleviating pain and symptoms, and in improving functional ability and finger and hand strength for mild and moderate CTS patients with no side effects.
authors.affiliation: Department of Bio-Industrial Mechatronics Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Wen-Dien
authors.initials: WD
authors.lastname: Chang
authors.forename: Jih-Huah
authors.initials: JH
authors.lastname: Wu
authors.forename: Joe-Air
authors.initials: JA
authors.lastname: Jiang
authors.forename: Chun-Yu
authors.initials: CY
authors.lastname: Yeh
authors.forename: Chien-Tsung
authors.initials: CT
authors.lastname: Tsai
mesh_terms: D002349:Carpal Tunnel Syndrome / Q000503:physiopathology / Q000532:radiotherapy*; D004311:Double-Blind Method; D018737:Hand Strength; D006801:Humans; D054023:Lasers, Semiconductor / Q000627:therapeutic use*; D008023:Ligaments, Articular / Q000528:radiation effects*; D028022:Low-Level Light Therapy; D008475:Median Nerve / Q000503:physiopathology; D008875:Middle Aged; D009431:Neural Conduction; D010147:Pain Measurement