Return to play in long-standing adductor-related groin pain: a Delphi study among experts

Key points

1. 01Strength: experts agreed on evaluating hip adductor isometric and eccentric strength with side-to-side symmetry as a key return-to-play criterion (96.9% agreed strength is a criterion).
2. 02Performance tests: planned and unplanned change-of-direction tasks at varying angles (45-90-110-180 degrees) reached strong consensus (96.9%); athletes must be pain-free and confident.
3. 03Sport-specific skills: agreed as a criterion by 96.9% of experts; athletes must be asymptomatic (75%) and self-confident (96.9%) during execution.
4. 04Imaging: the only section with negative consensus - 93.7% of experts agreed imaging should NOT be used as a return-to-play criterion.
5. 05Palpation, patient-reported outcome measures, intersegmental control, flexibility, and training load did not reach final consensus as formal criteria.

How it was conducted

Design

3-round Delphi consensus study

Participants

32 of 40 invited experts (80% acceptance rate); 28 from Europe, 3 from Australia, 1 from USA; healthcare practitioners with 2+ peer-reviewed publications in groin pain

Rounds

Round 1: open and closed questions across 9 sections; Round 2: items reaching >=70% threshold from Round 1; Round 3: Likert-scale rating (1-5) of remaining items

Consensus threshold

Round 3 required mean rating >=3.5, CV% <=30%, agreement >=70%, and Kendall's W p<0.05

Timeline

February 2020 to July 2020

Primary outcome

Expert consensus on return-to-play criteria for long-standing adductor-related groin pain

What they found

• Response rate was 100% across all 3 rounds; 32/40 experts (80%) participated.
• Round 1 positive consensus sections: Palpation (78.1%), Strength (96.9%), PROMs (71.9%), Intersegmental Control (71.9%), Performance tests (78.1%), Sport-specific skills (87.5%). Imaging reached negative consensus (75%).
• Round 2 retained positive consensus for: Strength (93.8%), Performance tests (90.6%), Sport-specific skills (90.6%); Imaging confirmed negative (78.1%). Palpation, PROMs, and Intersegmental Control lost consensus.
• Round 3 Kendall's W = 0.03 (p<0.001), confirming robustness. Mean CV% = 18.3% (range 12.9-28.7%); mean agreement rate = 84.4% (range 65.6-96.9%).
• Strength section: adductor isometric strength agreed by 75%, eccentric strength by 84.4%; side-to-side symmetry agreed by 87.6%.
• Imaging negative consensus confirmed at 93.7% in Round 3.
• Performance tests: planned/unplanned COD agreed at 96.9%; pain-free requirement agreed at 78.1%, athlete confidence at 93.7%.
• Sport-specific skills: overall criterion agreed at 96.9%; pain-free requirement at 75%, confidence requirement at 96.9%.

Limitations

• Geographical over-representation of European experts (87.5%) may limit generalisability to other sports cultures and settings.
• Consensus reflects expert opinion and practical experience, not direct experimental evidence; findings are not based on controlled clinical studies.
• Restricting eligibility to English-language proficiency may have excluded relevant experts from non-English-speaking regions.
• Only 4 of 9 assessed categories reached final consensus, leaving several clinically relevant domains (palpation, PROMs, intersegmental control, training load) without agreed guidance.

Why it matters

For patients

Athletes with long-standing groin pain can expect their clinician to assess their strength, change-of-direction ability, and sport-specific skills - and to require them to be pain-free and confident - before clearing them to compete.

For clinicians

Until higher-quality evidence exists, this consensus framework provides a practical first-step checklist: adductor strength (isometric and eccentric, side-to-side symmetry), COD performance tests, and sport-specific skill execution - all pain-free - are the agreed minimal physical requirements for return to play.

For readers

This Delphi study fills a practical gap by producing structured, expert-agreed criteria for a common and poorly managed sports injury, though the findings should be treated as provisional until validated in prospective cohort studies.