Groin Injuries:
Groin strains are injuries incurred to the adductor muscles located on the middle aspect of the thigh. They occur in sports which involve repetitive kicking and twisting and are commonly seen in most field sports, equating to 11% to 16% of all soccer injuries seen. They can occur from either a one off forceful contraction (tear) or from ongoing repetitive micro-traumas to the muscle or tendon (tendinopathy). The most common mechanism for these types of injuries include a quick change of direction or during a kicking action.
There are four groin muscles that make up the inner part of the thigh. All playing similar roles in stabilising the hip in both running, kicking, jumping and change of direction. The most commonly injured of the groin muscles being the adductor longus (most superficial).
- Adductor Longus
- Adductor Brevis
- Adductor Magnus
- Pectineus
The groin muscles attach onto the pelvis in close proximity to the tendons of the abdominal muscles. These two muscle groups work together to create cross body stability and power during kicking and sprinting. When injuring the groin muscles, the abdominal muscles as well as the hip flexor muscles, must be addressed during rehabilitation to reduce the chance of re-occurrence and to ensure a full return to function.
Before commencing rehab on an injured groin muscle, other causes of pain or contributing factors should be ruled out first. The other possible causes of pain include:
- Hip flexor strain
- Abdominal strain
- Hamstring strain
- Abdominal strain
- Osteitis Pubis
- Inguinal hernia (Athletic pubalgia)
- Hip Joint pain
- Low back or SIJ referred pain
Current evidence:
Groin pain once chronic (greater than 6 weeks of pain) often has better results with surgery than with rehab alone. A study looking at return to sport after undergoing surgery or a period of exercise and physiotherapy, compared the effectiveness of the two treatments. After 3 months, 90% of the surgery group returned to sport compared to 27% of the exercise only group. Although there are some limitations to this study, it does outline the importance of dealing with groins strains in their first incidence to ensure a return to function and to avoid the need for surgery.
Brinck et. al, 2011
A recent systematic review investigated the evidence on physiotherapy aimed at strengthening and coordinating the muscles stabilising the hip and pelvis when treating groin pain; compared to passive treatments of physiotherapy. They found that there is level 1 evidence that a more pro-active and strengthening approach leads to superior results compared with passive physical therapy.
Jansen et. al, 2008
Research looking to identify common risk factors that athletes and patients had in common around the time of their groin strain, identified the following to be correlated:
Tyler et. al, 2010
- A previous injury to groin = Increased risk of re-occurrence
- Preseason practice sessions, more attendance = reduced risk of injury
- Level of experience, more experience = reduced risk of injury
Rehabilitation:
Rehab involves strengthening the injured muscle or tendon and working on stability of the entire hip joint. Given the frequency of athletes with recurrent groin injuries it is crucial to address all contributing factors before returning to play. Tendinopathies requiring high load / strength exercises over a > 3-month period whilst acute strains requiring rest, gradual exercise and a program targeted at eccentric strength and force production.
Modalities used:
- Clinical exercise
- Exercise programs
- Massage
- Dry needling
- Cortisone / PRP injections
- Shockwave therapy (Chronic tendon)
- Surgery (severe ruptures or chronic instability)
TAKE HOME:
Groin strains are a common injury, especially in adolescents and in field sports involving twisting and kicking. They are often trickier than other lower limb injuries to manage due to their role in stabilising the hip and producing power with running and kicking movements.
A proper diagnosis is crucial to prevent a acute groin strain becoming chronic – where surgery is the likely avenue which can mean up to or greater than a year off from sport. Early diagnosis is crucial to ensure return to play is done correctly and to reduce the chance of re-injury.