Any one familiar with twitter may have seen the recent hash tag for the 1st World Conference on goring pain in athletes (#Groin2014). This conference in Doha, Qatar was brilliantly orchestrated by Adam Weir (@AdamWeirSports) and his team at Aspetar. Run over three days and cram packed with information, I’m going to try and summarise the points that I found most interesting and thought provoking – please be aware these are my interpretations of what other speakers said and do not serve justice to the quality of the talks and presentations.
I have themed the findings into 3 main categories: Epidemiology; Adductor related pathologies & Femoral Acetabular Impingement (FAI) (Not an exclusive list of things discussed at the conference)
What quickly became clear through the presenters was that even in 2014, we categorise injuries far too broadly. Consider the structures involved in the “Groin” and its no wonder why this area of the body see’s such huge injury occurrences. Also, our terminology needs to be more accurate. Per Holmich (@PerHolmich) brilliantly said “Pubalgia is as specific as saying Kneealgia” we need to be more concise with our terms if we are going to understand the pathologies and management better.
That said, a lot of the current research into epidemiology does categories pathologies into hip /groin. So we have to go with the stats that are in front of us. And what are they…
Of 110 multi-sport athletes assessed by Andreas Serner (@aserner), 76% of these injuries occurred in football-code sports. Markus Walden’s (@MarkusWalden) systematic review of 12 papers found that “Groin injuries” accounted for 9-18% of all injuries in mens football, with greater time loss of injury seen in tournament football compared to the regular season. Is this because of better monitoring at club level? Where medical teams know the players in a detail that international staff can’t due to limited exposure to players? Or as Walden says, is it due to the acute nature of injuries in tournaments due to reduced recovery and increased fatigue?
Both Walden and John Orchard (@DrJohnOrchard) found a greater incidence of groin injuries in men compared to women. It was suggested that the anatomical variance in womens hips puts them at more risk of lateral hip and knee pain rather than groin pain. The inguinal canal deficiency is also greater in men than womens.
Adductor Related Pathologies
Walden reports that 64% of groin related injuries are adductor related. This was supported by Serners paper with adductor longus being the most frequently injured of the adductor muscles. The picture below demonstrates Serners findings that 1/4 of all diagnosed injuries are negative on imaging, and that clinical presentations of rectus femoris & iliopsoas especially, often appear different on imaging.
Looking at risk factors for adductor pathologies, Jackie Whittaker (@jwhittak_physio) highlighted the basic but fundamental fact that previous injury is the biggest risk factor for future adductor pathology. Secondary to this, isolated adductor strength is a good indicator – ability to perform a squat is not! (Useful for those collating Injury Screening tools). Building on from Whittaker, Andrea Mosler (@AndreaBMosler) agreed that reduced strength coupled with positive pain on 45 degree adductor squeeze highlighted strong evidence for future groin pathology. Mosler summarised the following battery of tests for risk factors with adductor related groin pain:
Adductor strength – Strong evidence that low scores indicate future groin pain
BKFO (Bent knee fall out) – strong evidence that less flexible patients have greater risk of pathology
IR (Internal Rotation) – moderate evidence between decreased IR range and pathology
ER (External Rotation) in neutral – NO evidence to link decreased range and pathology. (Despite this lack of evidence, Geoff Verrall (@GeoffreyVerrall) does highlight a loss of ER in sport due tightening of the pubofemroal ligament and shortening of the adductors – improving this ER will help with force dissipation – so assessment is still valid!)
Eamonn Delahunt (@EamonnDelahunt) presented his research findings of squeeze assessments and groin pathologies, concluding that 45 degree squeeze has the highest sEMG and strength values (mmHg) of the 3 traditional squeeze measures. Contradictory to Moslers & Delahunts assessment of the adductors, Kristian Thorborg (@KThorborg) favoured long lever assessment when assessing for strength and pain. Pain provocation tests at a 0-degree squeeze is the best assessment to “rule adductor longus in.” While Delahunt drew his conclusions from a small population of gaelic footballers over a 6 month review period, Thorborg presented around 12 of his studies looking into the assessment of groin related pathologies. What is worth considering, is what structures are being affected when testing at these different ranges. As you’ll see below, it is a very complex and integrated part of the body.
Anthony Schache emphasised the importance of understanding the anatomy of the groin, in particular the soft tissue attachments. “Antomoy books provide discrete anatomy definitions which implies discrete anatomy – but this is not true.” The image below highlights the intimate attachments of surrounding structures in the groin.
Per Holmich was keen to build further on these assessments as part of a clinical diagnosis, saying that adductor pain replicated with stress tests PLUS pain on palpation of the adductor origin (must be “the patients pain”) indicates that the adductors are the main driver of pain – any one identifying factor on its own is not enough to indicate a diagnosis. But, consider what Schache said about the anatomy – we would need to ensure that our palpation skills were incredibly accurate. You can see how being a centimetre out when palpating the pubic bone for the adductor origin could be the difference between adductor longus (AL) or gracilis, or rectus abdominus. For this reason, its important to take your time when palpating this area, although it can be uncomfortable for both practitioner and patient, but confidently & slowly working your way around the attachments could help improve your diagnosis.
Of significant interest regarding the adductors is the difference in anatomy. Stephanie Woodley describes the intramuscular tendon of AL as being 23% of the femur length, compared to 11% of femur length for adductor brevis. Also significant is the decreased vascularity of AL, less than that of brevis and both of these are less than that of gracilis. If we now consider that AL is the most commonly injured structure in the groin, could this be a cause of injury rates? At any rate, it is certainly a consideration worth knowing for healing times.
Both Damian Griffin and Joanne Kemp (@JoanneLKemp) were keen to clarify the terminology of FAI. FAI relates to the pain caused by a CAM or Pincer lesion, CAM or pincer lesions don’t necessarily mean FAI.
“Athletes will undergo increased loads and greater demands on joints (ROM) than the general public, therefore impingements that are asymptomatic with ADL’s become FAI in sporting population” Damian Griffin.
Rintje Agricola describes an increased risk of FAI in males, especially in a sporting population but most interestingly reports that FAI is not prevalent in the non-athletes – therefore are we looking at a preventable pathology?
We believe now that CAM deformities develop around 12-13 years old (Agricola and Kemp), the same age that IGF1, key for bone development, peaks in adolescent males. ER and flexion increase weight bearing through the femoral neck and lateral femoral head, around the growth plate, so increased physical activity at this stage of development will promote bony changes on these lateral surfaces. The population most at risk would athletes specialising in one sport, say football academies, where they increase their training volume and intensities as they physically mature.
If we understand this to be true, should we now seriously start to consider activity modification for children in this stage of development? Obviously we would need to understand stages and rate of physical maturity for individuals, and then there is a bigger debate of getting coaches on side for this change in loading.
The presence of a CAM deformity may not cause FAI in all individuals. However Schache gives an example where a CAM lesion may actually provide a false positive, or exacerbate existing symptoms. If we assessing IR range through a flexed position, a CAM lesion may act as a lever on the pubic synthesis and increase stress in this area. So a detailed assessment and knowledge of individual hip morphology would help us differentiate between an impingement or pubic synthesis stress.
Staying with this thought process of structural limitations through range, Morritz Tannast explained benefits of assessing rotation in neutral and through flexion. In a neutral hip, with legs hanging off the end of the plinth, we can assess the posterior wall of the hip joint. Extra-articular impingement in this position is most likely to come from the lesser trochanter and the ischium. In prone, we can assess the degree of ante torsion of the femoral head by looking at total range of rotation, so:
– Low antetorision would present as decreased IR and increased ER
– High antetorsion would therefore present as increased IR and decreased ER
Assessing through slight flexion, abduction and ER any extra articular impingement will be from the ischium up against the greater trochanter and our old friend, a CAM lesion. Griffin advocates the use of control and low speed with impingement tests, encouraging clinicians to explore the contact surface of the acetabular ring.
So far through this summary, we have stayed very insular with our assessment and anatomy. Kemp encourages the clinician to consider the control of the trunk with hip pathology. An increased anterior pelvic tile will equal and increased acetabular retroversion and a decreased IR at 90 hip flexion. Sometimes, it may not be the presence of a CAM deformity reducing that range, so on this final point summarising the hip and groin, I wold encourage people to still consider the bigger picture of the patient and what role the hip / groin plays in a combination of movement patterns and dysfunctions.
Taking this forward
There is a great deal, and I mean a huge amount, that I have not discussed. Secondary cleft signs of the pubic synthesis or surgical interventions for hip & groin pathology for example. But one topic I have not discussed that is probably glaringly obvious is the treatment and management.
In terms of exercise prescription, I think this will be led by your clinical abilities to diagnose the pathology (Remember Serners findings above, don’t just treat the scan!) Hopefully this summary will encourage to you read more of the presenters own works, or maybe it has re-enforced your understanding of what is a complex structure in the body. Essentially management of this area is much like any other in the body, we identify complications or restrictions and we address them. Usually this is a global approach, looking at the whole kinetic chain – remembering that this conference focused on a very key, but isolated area of that chain.
If you are still reading at this point, thanks for taking the time to read through what is arguably the most complex and detailed blog I’ll probably every write!
Yours in sport