Groin Pain Background
Chronic groin pain is an often debilitating condition and one for which the recovery is rarely smooth. One of the biggest challenges when dealing with groin pain is that, put simply, there is a lot of stuff going on there. All the muscles, tendons, joints and ligaments are very close anatomically and interact with each other meaning that it is often difficult to differentiate between structures. Clients commonly present with multiple structures involved (research would suggest this occurs in over 40% of cases) meaning getting a clear answer or diagnosis can sometimes be difficult.
Groin Pain Incidence
Groin pain is responsible for approximately 25% of AFL season injuries, 21% of Football/Soccer injuries and is more common in kicking sports and Ice Hockey. Approximately 1 in 3 professional athletes carry groin pain over the season break and will then start the next season with a pre-existing injury for the next medical team to manage. Commonly, the diagnosis may have been oversimplified considering only the adductor muscles as a cause in isolation resulting in an inadequate rehabilitation program and delayed recovery.
In the past, any pain in the groin that persisted for longer than 6 weeks was termed “Osteitis Pubis” which still gets used in media reports today. Unfortunately, there was no clear definition of what this involved which then impacted on our ability to better manage and research it. So, a few years ago, they put a group of 25 experts into a room in Doha and didn’t let them out until they had some consensus on defining groin pain, which became known as the Doha Agreement. The terminology was simplified indicating a general structure using the specific entities of adductor-, inguinal-, pubic- and iliopsoas- related groin pain as well as hip-related groin pain. All of the areas can refer pain into the groin, but may require differing rehabilitation pathways to recovery.
Before we get to the rehabilitation pathway, it is important to understand some of the anatomical structures involved.
Pubic Symphysis Anatomy
The pubic symphysis is a secondary cartilaginous joint, consisting of a wedge-shaped fibrocartilaginous interpubic disc situated between two layers of hyaline cartilage, which line the medial surfaces of the pubic bones. It is reinforced by 4 strong ligaments and surrounding muscles. The adductor longus, adductor brevis and rectus abdominus attach either side of the anterior pubic ligament and interpubic disc. The attachment of the adductor muscles via the interpubic disc to the rectus abdominus provides a mechanism for force transmission across the pubic symphysis.
The pubic symphysis is most susceptible to shearing forces, suggesting that force created by the adductor muscles and rectus abdominis can influence injury risk. The activation of the transversus abdominis provides compression across the superior portion of the pubic symphysis and works with the inferior pubic ligament and pelvic floor muscles to increase stability of the pubic symphysis. This requires effective muscle activation and strength of the above muscles and possibly weakness or poor muscle activation patterns can influence injury presentation and recovery.
Tendons around the Groin Region
Tendons may be affected by overloading through excessive exercise or strain beyond their capacity, but conversely may also become pathological through underloading. This process usually affects the underside of the tendon and is known as “Stress Shielding” where the tendon is not loaded enough in exercise which then leads to deconditioning resulting in tendon degeneration.
The most common of these tendons involved in groin pain are the Adductor Longus and the Rectus Abdominis. This commonly relates to increased anterior pelvic tilt or pelvic rotation causing increased length and subsequent load in these tendons. This is particularly the case in kicking sports as this picture shows, however is also significantly loaded in change of direction activities and sports using large range of hip motion such as dance and gymnastics.
Inguinal Canal Anatomy
The inguinal canal is a passage in the abdominal wall which conveys the spermatic cord in men and the round ligament in women as well as two small nerves from the abdominal cavity. The canal is larger and more prominent in men and the surrounding musculature is less developed than that in females. There may be a potential weakness in the abdominal wall which may be genetic or acquired and therefore a common site of herniation. The sides and roof of the canal are comprised of abdominal muscles and fascia. Of particular note are the transversus abdominis and internal oblique muscles which are commonly described as creating a “co-joined” or “conjoint” tendon where they insert onto the pubic tubercle. On contraction, they create a “window shutter” type mechanism to reduce the size of the external opening during athletic activity. If this mechanism fails, the external opening remains open and creates greater potential for bulging of the posterior abdominal wall, causing potential hernia.
Another potential source of injury around this region is to the external oblique musculotendinous complex which is responsible for trunk rotation. These structures can commonly interact and coexist with adductor related pain and once again is commonly found in kicking sports or martial arts.
The Iliopsoas Muscle
The Iliopsoas comprises of both the Iliacus and Psoas Major muscles which in most people combine to form a fused tendon before it inserts on the femur. The Psoas Major originates from the lower border of the T12 vertebra to the upper border of the L5 vertebra and has a role as a lumbar stabiliser as well as a hip flexor, while the Iliacus works over the hip joint and is responsible for early hip flexion in the running cycle. These muscles have a large role to play in tasks and sports that involve kicking and high speed running as they constantly are being stretched and are consequently working in a lengthened position. The Iliopsoas is open to overload particularly when the athlete cannot control the amount of pelvic movement when running or kicking which may lead to injury.
Other Groin Pain Diagnosis
Of course, there are other potential causes of groin pain in addition to those already described. Pain can be referred from the spine or SIJ, or from abdominal organs such as in appendicitis. Additionally, nerve entrapment or irritation can refer pain into the groin and mimic a more mechanical presentation and requires careful assessment to identify. The most common of these to consider are those that pass through the inguinal canal- the ilioinguinal and genitofemoral nerves, which can present with nearly identical pain patterns as adductor, pubic or inguinal related groin pain. There are also some serious problems that must be considered and ruled out including infection, tumours and autoimmune conditions.
Causes of Groin Pain
The factors leading to groin pain are often multi-factorial usually related to load but also the athlete’s mechanics of movement. There have been only a small handful of specific risk factors identified including adductor strength, previous injury, age and level of sport participation. Given this lack of information, it has made researching and preventing injuries more difficult. It is important to recognise any change in training or kicking loads, or changed team role that may have contributed to the onset of symptoms.
An interesting study by Falvey in 2016 suggested that those athletes with groin pain of any entity or cause had altered movement patterns when cutting or changing direction and he suggested that retraining these patterns may provide improvement of groin related symptoms and reduced injury recurrence.
There does also appear to be a relationship between hip range of motion and the risk of groin pain. While the type of groin pain implicated is not specific to any entity, the principle of absorbing high sports-related forces in a smaller “anatomical workspace” does make sense. Research by Igor Tak (2017) showed that if both hips have reduced total range of motion there is increased risk of some form of groin injury.
Groin Pain Treatment
There has not been much quality research on physiotherapy and exercise paradigms for long standing groin pain, however there have been 5 main studies over the past 20 years all using a similar protocol designed by Per Holmich in 1999. This study looked at athletes who had ceased sport participation and the undertook a 2 stage exercise program after which 78% returned to sport.
Holmich used a combination of abdominal and groin strengthening with balance and single leg control exercises loading across the pubic symphysis to achieve this outcome. While looking at this protocol, I do question the exercise selection with our more recent understanding of this region however 4 subsequent studies that have either used of modified this protocol continue to report well over 50% success within 4 months.
More recently, research by Enda King, an Irish Sports Physiotherapist, has focussed on a more mechanical approach to improve movement patterns following on the work by Falvey. While this has not utilised specific adductor strengthening, his approach has showed significant promise with return to sport rates being high in significantly less time that protocols involving the Holmich exercises.
While this may be seen as a significant change to the management of this often complex region, I do believe we need to consider both approaches with any individual athlete. Individual variations in presentation and cause are exceedingly high requiring a structured assessment to classify the entity or entities most likely involved in each case, which then requires an individual specific approach to maximise effectiveness of the program. This is certainly not an area that we adopt a one-size-fits-all policy and will likely require both specific exercise targeted at objective findings as well as mechanical retraining to improve outcomes and prevent a return of symptoms when the athlete restarts sport.
Other Groin Pain Treatment Options
In cases where groin pain has proven to be recalcitrant or not improving to allow the athlete to successfully return to sport, involvement of Sports and Exercise Physicians, sports Physiotherapsits or other groin specialists may be required. This can assist with treatment direction and consider other causes for the symptoms to persist as well as provide adjunctive treatment options. Surgery is commonly seen as another option and adductor lengthening surgery (an adductor tenotomy) can restore function in some patients.
Groin Pain Summary
Consequently, any client with longstanding groin pain needs a comprehensive history and examination to identify factors relating to the onset of their condition which can then allow more specific direction to plan an effective treatment plan. We have to recognise that the groin is a complex area, requiring a structured and evidence based approach allowing consistently high outcomes. While recovery usually takes place over 3-6 months, there are effective management strategies to get you back on the field in the interim.
If you have chronic groin pain that is limiting your sporting activity and want to get on the road to recovery, call one of our team at Newcastle Sports Medicine on 4910 0805.