Low Level Laser Therapy (LLLT) for Neck Pain: A Systematic Review and Meta-Regression
Purpose: This systematic review update evaluated low level laser therapy (LLLT) for adults with neck pain. Methods: Computerized searches (root up to Feb 2012) included pain, function/disability, quality of life (QoL) and global perceived effect (GPE). GRADE, effect-sizes, heterogeneity and meta-regression were assessed. Results: Of 17 trials, 10 demonstrated high risk of bias. For chronic neck pain, there was moderate quality evidence (2 trials, 109 participants) supporting LLLT over placebo to improve pain/disability/QoL/GPE up to intermediate-term (IT). For acute radiculopathy, cervical osteoarthritis or acute neck pain, low quality evidence suggested LLLT improves ST pain/function/QoL over a placebo. For chronic myofascial neck pain (5 trials, 188 participants), evidence was conflicting; a meta-regression of heterogeneous trials suggests super-pulsed LLLT increases the chance of a successful pain outcome. Conclusions: We found diverse evidence using LLLT for neck pain. LLLT may be beneficial for chronic neck pain/function/QoL. Larger long-term dosage trials are needed.