Low-level laser in the treatment of carpal tunnel syndrome: clinical, electrophysiological, and ultrasonographical evaluation

The objective of this study is to investigate the efficacy of low-level laser therapy (LLLT) in patients with carpal tunnel syndrome (CTS). Sixty patients with CTS were included in this placebo-controlled and double-blind study and randomly assigned to three treatment groups: active laser with a dosage of 1.2 J/per painful point, active laser with a dosage of 0.6 J/per painful point, and placebo groups. A total of 5 points across the median nerve trace were irradiated with Gal-Al-As diode laser. All groups were treated 5 times per week for 3 weeks. Clinical assessments included pain intensity, grip strength, symptom severity score (SSS), functional status score (FSS), nerve conduction studies, and cross-sectional area (CSA) of the median nerve as measured by ultrasonography. Compared to baseline, post-treatment VAS scores (group 1, P < 0.001; group 2, P < 0.001; group 3, P < 0.01), grip strength (P < 0.05), SSS scores (group 1, P < 0.001; group 2, P < 0.001; group 3, P < 0.01), and FSS scores (P < 0.05) improved significantly in all groups. Only sensorial nerve velocity measurements on the palmar region showed a significant improvement in both active laser groups (P < 0.01). There was no significant difference in any of the outcome measures among the groups. With the chosen laser type and dose regimen, the results suggested that LLLT was no more effective than placebo in CTS.