Efficacy of high-intensity laser therapy for patellofemoral pain: a systematic review and meta-analysis

Introduction

Patellofemoral pain (PFP) is a common cause of anterior knee pain, particularly among physically active individuals. High-intensity laser therapy (HILT) has shown analgesic effects in several musculoskeletal conditions; however, its role in PFP remains unclear.

Objective

To evaluate the effects of HILT in people with PFP.

Method

Randomized controlled trials (RCTs) evaluating HILT for PFP were identified through searches in PubMed, Scopus, Web of Science, CINAHL, MEDLINE, ScienceDirect, the Cochrane Library, and PEDro, with additional screening of reference lists and gray literature (last search: May 1, 2026). The primary outcome was pain intensity, while functional outcomes were considered secondary. Risk of bias was assessed using the Cochrane RoB 2 tool. Meta-analyses were conducted using standardized mean differences (SMDs) with 95% confidence intervals under a random-effects model. Certainty of evidence was evaluated using the GRADE framework.

Results

Four RCTs were included, with 77 participants allocated to HILT combined with exercise and 92 to control groups. The overall RoB was assessed as high across all included trials, primarily driven by concerns related to outcome measurement and selective reporting. All HILT protocols were delivered alongside therapeutic exercise (strengthening and/or stretching), and no included trial evaluated HILT as a standalone intervention. HILT resulted in a statistically significant reduction in pain at post-treatment (SMD = − 0.66; 95% CI − 0.98 to − 0.35; p < 0.01) and at follow-up (SMD = − 1.08; 95% CI − 1.89 to − 0.26; p < 0.01); however, the certainty of evidence was rated as very low due to high RoB across included trials, substantial heterogeneity (I² > 50%), and imprecision related to small sample sizes. No significant between-group differences were observed for functional outcomes (Kujala scale), for which the certainty of evidence was also very low due to similar methodological limitations.

Conclusion

HILT combined with therapeutic exercise may reduce pain in individuals with PFP; however, its independent effect cannot be determined. The very low certainty of the evidence limits confidence in these findings, and improvements in functional outcomes remain unclear. High-quality randomized controlled trials are required to clarify the role of HILT in PFP rehabilitation and to determine its potential contribution within multimodal treatment approaches.

Trial registration

CRD42025631248 (PROSPERO) (December 24, 2024).