Ferlito JV et al. - Photobiomodulation and Pain in Plantar Fasciitis

Photobiomodulation reduces pain intensity in plantar fasciitis in the short term, either alone or in combination with exercise, according to a meta-analysis of 19 randomized trials. Its effect on functional disability remains uncertain, and it does not improve outcomes when added to other electrotherapy modalities.

What this study measured

This is a systematic review with a meta-analysis, not a single clinical trial. The authors searched five databases to identify randomized controlled trials conducted in adults with plantar fasciitis. Three scenarios were compared: photobiomodulation versus a placebo, versus other interventions, and as an adjunct to other therapies. The outcomes assessed were pain intensity and functional disability. Methodological quality was assessed using the PEDro scale, and the level of certainty was evaluated using the GRADE approach. Nineteen randomized controlled trials involving a total of 1,089 participants were included.

Key Findings

The results are expressed as the mean difference (MD) along with its 95% confidence interval. The summary does not specify the pain scale used to calculate these differences.

• Photobiomodulation alone, short-term pain: SMD = -22.02 (95% CI: -35.21 to -8.83)
• Photobiomodulation combined with exercise, short-term pain: SM = -21.84 (95% CI: -26.14 to -17.54)
• Photobiomodulation versus extracorporeal shock waves for pain relief: SM = -20.94 (95% CI: -32.74 to -9.13)
• Photobiomodulation combined with exercise versus exercise alone, at follow-up: DM = -18.42 (95% CI: -26.48 to -10.36)
• Functional impairment: may be more effective than therapeutic ultrasound in the medium and long term, but the effect may not be clinically relevant
• Adding photobiomodulation to other electrotherapeutic modalities: no additional benefit on the outcomes studied

How photobiomodulation works for this indication

The mechanisms proposed in the literature remain hypothetical and were not tested in this review. Red and near-infrared light is thought to be absorbed by cytochrome c oxidase, a photon acceptor in the mitochondrial respiratory chain, which could promote ATP production in the exposed cells. This would result in a modulation of local inflammation in the fascia. An effect on nociceptive conduction and sensitivity thresholds could also contribute to the reported reduction in pain intensity. These explanations are presented as hypotheses: they have not been measured in this study.

Limits You Should Know

Several caveats accompany these results. The observed superiority applies only to the comparison with extracorporeal shock waves: photobiomodulation did not prove superior to other interventions, either in terms of pain or functional disability. The authors explicitly note uncertainty regarding its ability to improve functional disability. When used in conjunction with other electrotherapeutic modalities, it did not improve outcomes—a negative finding that limits the value of combination protocols. Finally, the parameters for dose, wavelength, and number of sessions are not included in the abstract; therefore, no optimal protocol can be determined from this study.

What This Means in Practice

These findings position photobiomodulation as a non-pharmacological option for short-term plantar fasciitis pain, particularly when combined with an exercise program. They do not justify combining it with other forms of electrotherapy. Follow-up by a healthcare professional remains essential to establish a diagnosis and rule out other causes of heel pain.

Frequently Asked Questions

Does photobiomodulation replace rehabilitation exercises?

No. In this review, the best results for pain relief at follow-up came from the combination of photobiomodulation and exercise, compared to exercise alone. Exercise remains the cornerstone of treatment, with photobiomodulation being studied as an adjunct.

How long do the effects last?

The review reports short-term pain relief and a sustained benefit at follow-up for the combination with exercise. The exact duration of the follow-up is not specified in the study abstract. Therefore, the duration of the effect cannot be quantified.

Is photobiomodulation more effective than shock waves?

Based solely on the criterion of pain relief, the meta-analysis reports an advantage for photobiomodulation over extracorporeal shock waves. This finding is based on pooled data and does not predict an individual response. The choice of treatment modality is a matter for professional judgment.

Reference

Ferlito JV, Silva CF, Almeida JC, da Silva Lopes IA, da Silva Almeida R, Leal-Junior ECP, De Marchi T. Effects of photobiomodulation therapy (PBMT) on the management of pain intensity and disability in plantar fasciitis: systematic review and meta-analysis. Lasers in Medical Science, 2023. PMID 37464155. DOI 10.1007/s10103-023-03823-0. https://doi.org/10.1007/s10103-023-03823-0

This summary is provided for informational purposes only and does not constitute medical advice. Photobiomodulation is not a substitute for prescribed treatment. Consult a healthcare professional.