Groin and Hip Injuries in Football — The Most Persistent Problem in the Game

Introduction

Groin injuries are the most common time-loss injury in professional football. They account for 12–16% of all injuries at elite level, have notoriously high recurrence rates, and frequently resist complete resolution — players returning from groin injuries often carry chronic pain that impairs training quality for months. The groin region’s anatomical complexity — five adductor muscles, hip flexors, abdominals, pubic symphysis, and hip joint all converging — means that the same symptom location can arise from multiple distinct pathologies requiring different management.

The Science

Anatomical complexity of the groin: The groin symptoms cluster involves structures from the adductor group (longus, brevis, magnus, pectineus, gracilis), iliopsoas (hip flexor), rectus abdominis, pubic symphysis, and hip joint. Distinguishing the primary pain generator requires systematic clinical examination and often imaging — MRI is the gold standard for groin injury classification.

Primary groin injury types in football:

1. Adductor muscle strain: The adductor longus (origin at pubis) is most commonly strained. Mechanism: forced abduction stretch or sudden forceful adduction (shooting, tackling). Classification by grade determines return-to-play timeline — Grade I (muscle pain, no structural damage): 1–2 weeks; Grade II (partial tear): 3–8 weeks; Grade III (complete tear): surgical evaluation required.

1. Athletic pubalgia/sports hernia: Chronic lower abdominal and groin pain arising from deficiency in the posterior inguinal wall, often associated with high-velocity hip extension and trunk rotation (kicking mechanics). Poorly understood, frequently misdiagnosed, and may require surgical repair in chronic cases.

1. Femoroacetabular impingement (FAI): Abnormal contact between femoral head and acetabulum during hip flexion — exacerbated by the kicking motion. Creates labral tearing and cartilage damage over time. FAI is found at high prevalence on imaging of professional footballers (estimated 55–77%) — but not all morphological FAI is symptomatic.

1. Hip flexor strain (iliopsoas): Mechanism: forceful hip flexion against resistance (e.g., tackling opponent mid-kick). Recovery typically faster than adductor strains but recurrence rate is high without specific rehabilitation.

Adductor strength as injury predictor: Reduced adductor-to-abductor strength ratio is a significant prospective risk factor for groin injury. Teams with systematic hip strength testing and rehabilitation protocols demonstrate significantly lower groin injury incidence.

What Research Says

Ekstrand et al. (2011) analysed 16 years of UEFA injury data in British Journal of Sports Medicine (across 24 clubs), confirming that groin injuries account for 12–16% of all injuries in professional football, that recurrence rates are among the highest of any injury type (22–30%), and that adductor strength deficits are the most consistently modifiable risk factor.

Tyler et al. (2001) demonstrated in American Journal of Sports Medicine that hip adductor weakness (measured on isokinetic dynamometer) predicted groin injury in professional ice hockey players with high sensitivity — and that a preseason adductor strengthening programme in players identified as at-risk significantly reduced injury incidence. The football equivalent data parallels these findings.

Harøy et al. (2019) published the Copenhagen Adductor Exercise as a groin injury prevention exercise in British Journal of Sports Medicine, demonstrating that 6 weeks of Copenhagen adductor exercises (partner-assisted adductor eccentric loading) significantly increased adductor strength and reduced injury incidence in a professional football population.

Did You Know? The Copenhagen Adductor Exercise — developed from a simple observation that no football-specific adductor strengthening exercise existed comparable to the Nordic hamstring curl — is now the most widely implemented groin prevention tool in professional football. A player lies on their side supported on one forearm; a partner holds the top leg at ankle height; the player performs a side plank while lowering and raising the unsupported bottom leg, loading the adductors eccentrically. Two sets of 12 reps, 3 times per week, was the training dose in the original prevention trials.

Applied to Football

Groin injury prevention and management framework:

1. Copenhagen Adductor Exercise in every warm-up. Two sets of 12 reps (bilateral) 3 times per week reduces groin injury incidence. Include from pre-season through the full season.
2. Hip adductor/abductor strength screening. Annual isokinetic or clinical manual muscle testing. Players with adductor-to-abductor ratio <80% or absolute adductor weakness are in the targeted prevention group.
3. Never rush groin injury return-to-play. Premature return from Grade II adductor strain is the primary driver of recurrence. Full pain-free adduction strength (≥90% of contralateral side) is the required return threshold.
4. Distinguish adductor strain from FAI and pubalgia before rehabilitation. MRI at presentation for groin injuries persisting >2 weeks. Adductor strain rehabilitation is counterproductive for FAI-related symptoms.
5. Graduated kicking load in return-to-play. Kicking mechanics are the highest-load event for groin structures. Graduated kicking volume (low-intensity passing → full shooting → training → match) in return is non-negotiable.

Key Takeaways

• Groin injuries represent 12–16% of all professional football injuries with 22–30% recurrence rates
• Adductor weakness is the most consistently modifiable risk factor for groin injury
• Copenhagen Adductor Exercise reduces injury incidence and improves adductor strength in professional populations
• FAI (femoroacetabular impingement) is present on imaging in 55–77% of professional players — distinguish symptomatic from incidental
• Grade II adductor strain requires full strength restoration (≥90% contralateral) before return — not just pain clearance

References

• Ekstrand, J., Hagglund, M., & Waldén, M. (2011). Injury incidence and injury patterns in professional football: the UEFA injury study. British Journal of Sports Medicine, 45(7), 553–558.
• Harøy, J., Clarsen, B., Wiger, E. G., Øyen, M. G., Serner, A., Thorborg, K., … & Bahr, R. (2019). The Adductor Strengthening Programme prevents groin problems among male football players: a cluster-randomised controlled trial. British Journal of Sports Medicine, 53(3), 145–152.
• Tyler, T. F., Nicholas, S. J., Campbell, R. J., & McHugh, M. P. (2001). The association of hip strength and flexibility with the incidence of adductor muscle strains in professional ice hockey players. American Journal of Sports Medicine, 29(2), 124–128.
• Weir, A., Brukner, P., Delahunt, E., Ekstrand, J., Griffin, D., & Khan, K. M. (2015). Doha agreement meeting on terminology and definitions in groin pain in athletes. British Journal of Sports Medicine, 49(12), 768–774.