Pinfildi C.E.1, Bisset L.2, Xavier M.O.3, Evans K.2, Laakso L.2
1Federal University of São Paulo - Unifesp, Health and Movement Science, Santos, Brazil, 2Griffith University, School of Allied Health of Sciences, Gold Coast, Australia, 3Federal University of Vales do Jequitinhonha e Mucuri, Physical Therapy Department, Diamantina, Brazil
Background: Laser photobiomodulation therapy (PBMt) has been used with the aim to improve tissue repair and decrease pain in people with lateral epicondylalgia (LE) or tennis elbow. However, there is no consensus in the literature regarding the site of laser application which may be critical for efficacy of treatment.
Purpose: To understand how to best target PBMt for LE, we investigated: (1) blood flux patterns at the lateral elbow region; and (2) if PBM increases elbow blood flux at the site of application when delivered to identified target points.
Methods: All participants were healthy volunteers without LE symptoms. This placebo-controlled study was divided in two phases. Phase 1: Ten volunteers were recruited with the aim to assess elbow blood flux with laser doppler at six pre-determined anatomical positions. Phase 2: Lateral elbow blood flux response was evaluated in eight volunteers during low-level laser PBMt. Measurements were performed immediately before and after placebo or PBMt. The laser device used was: 904 nm GaAs, average power output 90 mW, pulse duration 200 ns, pulse frequency 10 kHz with total dose of 4J (42s). Statistical analysis for both phases used repeated measures ANOVA and post-hoc Bonferroni multiple comparisons. The alpha level was set at 0.05.
Results: In phase one, the highest mean blood flux measures were at points on the lateral supracondylar ridge and lateral epicondyle. In phase two, there was a significant difference (p 0.05) between pre-placebo, placebo and pre-PBMt measurement periods compared to the PBMt period. There was no change in mean blood flux measures in the pre-placebo, placebo or pre-PBMt periods.
Conclusion(s): Selective zones of elbow vascularity can be influenced with PBM in particular the lateral supracondylar ridge which may be considered an effective target for laser PBMt in LE.
Implications: This investigation highlights the potential importance of targeting specific points of elbow vascularity that may contribute to the optimization of laser PBMt for LE treatment.
Funding acknowledgements: Thanks to the Griffith University for granted this study
Topic: Musculoskeletal: upper limb
Ethics approval: This study was granted by the Human Research Ethics Committee - Griffith University in accordance with (NHMRC) (1999) (GU AHS/55/14/HREC).
All authors, affiliations and abstracts have been published as submitted.
