An interventional study of Photobiomodulation (Low-Level Laser Therapy) and Sham Photobiomodulation (Sham Laser Treatment) in Osgood-Schlatter Disease and Sever's Disease, sponsored by Medical University of Gdansk. Recruiting at 1 site in Poland. Open to participants aged 10 Years to 17 Years. Per ClinicalTrials.gov, last updated 2026-10-09.
Sponsored by Medical University of Gdansk · Not applicable, Interventional, and Treatment
The goal of this clinical trial is to learn if low-level laser therapy (also called photobiomodulation) works to treat knee or heel pain in physically active children and adolescents with Osgood-Schlatter disease or Sever disease. It will also learn about the safety of this treatment. The main questions it aims to answer are:
Researchers will compare active low-level laser therapy to a sham (placebo) laser treatment. The sham treatment looks and feels the same but does not deliver therapeutic light. This comparison will show whether the laser therapy works better than placebo.
Participants will:
Participants will not know which treatment group they are in until the study ends.
This pilot randomized, participant-blinded, sham-controlled trial evaluates the feasibility, safety, and preliminary clinical signals of low-level laser photobiomodulation (low-level laser therapy; LLLT) in youth athletes (10-17 years) with symptomatic lower-extremity apophyseal pathology, primarily consistent with Osgood-Schlatter disease and/or calcaneal apophysitis (Sever disease) confirmed clinically and by ultrasound.
Participants are randomized 1:1 to active photobiomodulation or sham treatment and receive 10 sessions over 2 weeks delivered with a class 3B GaAlAs (Gallium-Aluminum-Arsenide) laser device using standardized parameters (near-infrared wavelength range; continuous mode; preset energy density; contact application over the symptomatic apophyseal region). Sham procedures are identical in appearance, session duration, and device operation but deliver 0 mW output.
The primary objective is feasibility (recruitment, retention, adherence, data completeness, safety). Secondary objectives are estimate-only between-group differences in pain and function at post-intervention and follow-up. Ultrasound is repeated after the intervention as an exploratory mechanistic assessment. Blood samples are collected at baseline only and are not repeated after the intervention.
After completion of the 2-week intervention and the immediate post-intervention assessment (T1), participants are offered the separately registered LEAP-REHAB exercise programme (NCT07521280; 12 weeks, started after the end of laser sessions), and most randomized participants entered it. No separate 3-month visit is performed. The 3-month outcomes are taken from the LEAP-REHAB visit closest to 3 months after the end of laser sessions (within 4 weeks), performed by physiotherapists who were not informed of the laser allocation. They therefore reflect the laser course followed by, or overlapping with, the exercise programme. Both study arms were eligible for the exercise programme on the same terms. The global rating of change in LEAP-REHAB refers to the start of the exercise programme, and a 3-month rating anchored to the pre-laser baseline is available only for participants in whom that item was collected. Participants who did not take part in LEAP-REHAB have missing 3-month data and are reported as lost to follow-up.
Allocation was assigned by drawing sealed opaque envelopes, without replacement, from a prepared pool containing equal numbers of active and sham envelopes. Allocation was not stratified.
The planned sample size was increased from 30 to 36 (18 per arm) to allow for attrition, and the recruitment window was extended to 31 December 2026 because the originally anticipated recruitment period was not met. These changes were made before any analysis of outcomes. Enrollment during the first recruitment phase was restricted to male participants. Whether female participants will be randomized in this trial will be specified before they are enrolled.
16 studies on the registry are indexed under Osteochondrosis; 5 are open to participants now.
This study's planned enrollment of 36 is below the median of 51 across 13 interventional studies indexed under Osteochondrosis.
Browse Osteochondrosis studies →Medical University of Gdansk is the lead sponsor of 133 studies on the registry; 46 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive active photobiomodulation (low-level laser therapy) applied to the symptomatic apophyseal region (tibial tubercle for Osgood-Schlatter-type pain and/or calcaneal region for Sever-type pain) using standardized device settings and application procedures. Treatment will be delivered in a series of sessions over the intervention period. All participants will also receive the same standardized conservative-care guidance (e.g., education and exercise/activity advice) provided to both study arms.
Device: Photobiomodulation (Low-Level Laser Therapy)
Participants will receive sham (placebo) laser treatment using the same device appearance, positioning, contact, and session schedule as the active intervention, but without delivery of therapeutic light. The sham procedure is designed to maintain blinding. All participants will also receive the same standardized conservative-care guidance (e.g., education and exercise/activity advice) provided to both study arms.
Device: Sham Photobiomodulation (Sham Laser Treatment)
Active photobiomodulation (low-level laser therapy) delivered using a laser device applied to the symptomatic apophyseal region (tibial tubercle for Osgood-Schlatter-type pain and/or calcaneal region for Sever-type pain). Sessions will be provided according to a standardized schedule and preset device parameters (wavelength/output/dose and application time) specified in the protocol.
Also known as: Low-Level Laser Therapy, Laser Photobiomodulation
Sham (placebo) photobiomodulation delivered with an identical device appearance and treatment routine (positioning, contact, and session duration) but without delivery of therapeutic light. The sham procedure is intended to maintain participant blinding and matches the active intervention schedule.
Also known as: Placebo Laser Treatment, Inactive Laser Treatment
Recruitment feasibility: proportion of eligible participants enrolled
Proportion enrolled among eligible candidates; threshold ≥80% within the recruitment window.
Time frame: From first screening contact through completion of enrollment.
Retention feasibility: proportion completing post-intervention and follow-up assessments
Proportion of randomized participants with complete assessments at baseline and post-intervention, and with 3-month follow-up data taken from LEAP-REHAB; threshold 20% attrition.
Time frame: Baseline to post-intervention (≈2 weeks) and baseline to ≈3 months after the end of laser sessions.
Adherence feasibility: proportion of intervention sessions completed
Percentage of planned sessions completed (10 total); threshold ≥8/10 sessions and ≥80% adherence.
Time frame: During the 2-week intervention period.
Data completeness feasibility: proportion of complete datasets for key clinical outcomes
Proportion of randomized participants with complete data for NPRS, PGIC, the applicable site-specific function measure (KOOS-Child or OxAFQ-C), treatment adherence, safety, and blinding-assessment fields. Target: at least 90% completeness of expected measurements.
Time frame: Baseline through approximately 3 months after the end of laser sessions.
Safety and tolerability: number and type of adverse events related to the intervention
Count and classification of adverse events temporally associated with treatment sessions.
Time frame: During the 2-week intervention period.
Blinding credibility: participant allocation guesses
After the immediate post-intervention assessment, participants guess whether they received active treatment or sham treatment, or indicate that they do not know, and rate their confidence. The proportion of correct guesses and Bang's blinding index with 95% confidence intervals are summarized descriptively.
Time frame: Immediately after the 2-week intervention
Proportion of Participants Rated as Responders on the Patient Global Impression of Change (PGIC) at 2 Weeks
PGIC is a 7-point global change scale from "very much improved" to "very much worse." A responder is defined as "much improved" or "very much improved".
Time frame: 2 weeks
Proportion of Participants Rated as Responders on the Patient Global Impression of Change (PGIC) at 3 Months
PGIC is a 7-point global change scale from "very much improved" to "very much worse." A responder is defined as "much improved" or "very much improved."
Time frame: 3 months
Change From Baseline in Pain Intensity as Measured by the Numeric Pain Rating Scale (NPRS) at 2 Weeks
NPRS ranges from 0 to 10, where 0 = no pain and 10 = worst pain imaginable. Pain intensity refers to worst pain in the last 7 days. The metric is change from baseline to 2 weeks.
Time frame: Baseline and 2 weeks
Change From Baseline in Pain Intensity as Measured by the Numeric Pain Rating Scale (NPRS) at 3 Months
NPRS ranges from 0 to 10, where 0 = no pain and 10 = worst pain imaginable. Pain intensity refers to worst pain in the last 7 days. The metric is change from baseline to 3 months.
Time frame: Baseline and 3 months
Change From Baseline in Knee Function as Measured by the KOOS-Child at 2 Weeks (Osgood-Schlatter Subgroup)
KOOS-Child subscale scores are transformed to a 0 to 100 scale, where higher scores indicate better knee status (fewer symptoms/better function). The metric is change from baseline to 2 weeks, assessed in the Osgood-Schlatter subgroup only.
Time frame: Baseline and 2 weeks
Change From Baseline in Knee Function as Measured by the KOOS-Child at 3 Months (Osgood-Schlatter Subgroup)
KOOS-Child subscale scores are transformed to a 0 to 100 scale, where higher scores indicate better knee status. The metric is change from baseline to 3 months, assessed in the Osgood-Schlatter subgroup only.
Time frame: Baseline and 3 months
Change From Baseline in Foot/Ankle Function (OxAFQ-C) at Post-intervention (2 weeks), Sever Subgroup Only
OxAFQ-C domains 0-100 (higher=better). Metric: change from baseline to ≈2 weeks. Assessed only in Sever participants.
Time frame: Baseline and 2 weeks
Change From Baseline in Foot/Ankle Function (OxAFQ-C) at Follow-up (3 months), Sever Subgroup Only
OxAFQ-C domains 0-100 (higher=better). Metric: change from baseline to 3 months.
Time frame: Baseline and 3 months
Change From Baseline in Ultrasound Features of the Symptomatic Apophysis at 2 Weeks
Musculoskeletal ultrasound of the index symptomatic apophyseal site using a standardized acquisition protocol (high-frequency linear probe; fixed patient position). Predefined features will be graded on ordinal scales and summed into a prespecified composite "ultrasound severity score" (higher = greater abnormality). Features include: (1) apophyseal fragmentation/irregularity, (2) tendon insertion thickening, (3) hypoechogenicity, (4) bursal fluid/soft-tissue swelling. Metric: change in composite score from baseline to 2 weeks.
Time frame: Baseline and 2 weeks
Treatment Expectancy and Credibility (TEC-C / TEC-P) at Baseline (Pre-intervention)
Treatment expectancy and credibility will be assessed in the child and parent/caregiver using pediatric versions of the Treatment Expectancy and Credibility measure (TEC-C and TEC-P). The child and caregiver complete the questionnaires independently (without influence on each other's responses). Scores are derived per instrument instructions (higher scores indicate greater expectancy/credibility).
Time frame: Pre-intervention (baseline), prior to the first treatment session and prior to functional testing.
Plan to share: Yes — De-identified individual participant data (IPD) that underlie the results reported in publications from this trial, along with a data dictionary, will be made available to qualified researchers. Data will include baseline characteristics, group allocation (coded), outcome measures, and adverse events. Data will be shared after publication of the primary results and will remain available for at least 5 years. Access will be provided upon reasonable request and approval of a methodologically sound proposal, with a signed data use agreement, and only for non-commercial research purposes. Supporting documents (protocol and statistical analysis plan) will be shared.
Time frame: Beginning after publication of the primary results and for at least 5 years.
Access criteria: Reasonable request to the principal investigator, a methodologically sound proposal, and a signed data use agreement, for non-commercial research purposes.
No publications or documents are linked to this record.
Started Mar 2026 (actual). Primary completion is estimated for Apr 2027, 13 months after the start.
Since we started tracking on Sep 25, 2026, the dates moved once, on Oct 9, 2026: primary completion Feb 2027 → Apr 2027 and completion Feb 2029 → May 2027.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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