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Home , Adductor longus muscle, Athletic pubalgia, Groin, PELVIS syndrome

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GROIN PAIN: A VIEW FROM BELOW The impact of lower extremity function and podiatric interventions

– Written by Michael Kinchington, Australia

INTRODUCTION pain in sport, there is a lack of evidence- The objective of this paper is to: The evaluation and treatment of based regarding diagnosis and 1. Review causes of groin pain in the pain in athletes is challenging, often conservative management of groin pain. athlete. because the anatomy is complex, multiple This is surprising as the morbidity of groin 2. Examine potential biomechanical risk coexist that can cause similar pain ranks only behind , anterior factors for groin pain. symptoms and the causation of injury cruciate injury and bone fracture 3. Explore the role of in the is multi-factorial. Athletic groin injuries in terms of time loss from sport1. Much management of the athletic groin pain. are more prevalent in sports that involve of the scientific literature relies upon an kicking and twisting movements while association between qualitative history running. Sports such as ice hockey, fencing, taking, clinical appraisal and diagnostic handball, cross-country skiing, hurdling, imaging. Hence, links between groin pain high jumping and football (soccer and and lower extremity biomechanics are Asymmetry Australian Rules) commonly have a high poorly represented within the scientific incidence of groin injury. Groin pain literature. Despite the lack of an evidence of the legs is accounts for approximately 5 to 18% of base, clinically the link between - all athletic injuries, with kicking sports biomechanics, leg length inequality and considered a risk generally producing most of these injuries. pelvic instability is clear. Within the clinical For example, the literature indicates that realm of sports injury, biomechanical factor for injury nearly 1/3 of soccer players will develop optimisation principals are frequently groin pain during the course of their careers. utilised to prevent, rehabilitate and manage Yet, despite the high prevalence of groin groin pain.

360 Sportsman’s Figure 1: Anatomy of athletic pubalgia or ‘groin disruption injury’.

kicking, changing directions and tenderness of the exacerbated by provocative examination techniques.

Sports hernia Obturator Sports hernia is a medially-located bulge entrapment in the posterior wall of the due to weakening of the abdominal wall3. This has been attributed to an injury of the (common insertion of internal oblique and transverse abdominus muscles joining the distal lateral edge of rectus abdominus). The conjoint tendon with the lower edge of internal oblique and Adductor tendinopathy transverse abdominus muscles protects the posterior wall of the inguinal canal ( transversalis), a weak point in the abdominal Osteitis wall. The is explained as interplay of opposing forces between the abdominal and adductor muscles. Conjoint tendon CAUSES OF GROIN PAIN IN THE ATHLETE avulsion fractures can also occur at the is the inferomedial portion of internal Groin pain reviewed attachment of the adductor tendons to oblique (trunk rotation and lateral flexion) The definition of groin pain is broad and the pubic bone, as well as repetitive micro- and transversal abdominus (core stability) vague. The literature provides no consensus trauma or shearing forces to the pubic muscles. The role of adductors is adduction, on pathology/pathophysiology or manage- symphysis. This micro-trauma exceeds the flexion and internal rotation of the . The ment. Groin pain involves a number of dynamic tissue capacity for hypertrophic condition presents often, and has complex conditions involving the lower , remodelling, resulting in tissue degenera- clinical findings and historically varying inguinal regions, proximal adductors and tion. The condition is overuse in nature, terminology. It is interchangeably referred perineum, upper anterior and hip. caused by repetitive contraction of the to as a sportsman’s hernia, pre-hernia The most commonly seen groin pathology muscles that attach to the pubic bone complex, conjoint tendon tear, Gilmore’s is related to the adductor muscles, pubic and the pubic symphysis. Actions such groin, external oblique tear and inguinal symphysis, inguinal region and nerve as running, jumping, kicking and rapid wall deficiency4,5. Athletes who participate supply to the groin. changes of direction cause the abdominal in sports that require repetitive twisting Diagnosis is complicated by multiple and groin muscles to produce a pulling and turning at speed (Australian Rules groin pathologies presenting at one time. or traction force on the pubic bone. This football, soccer, hockey) are at most risk of This is referred to as ‘’, a adds to the suboptimal biomechanics of developing a ‘sports hernia’. generalised term that refers to a spectrum the and lower extremity, and results The mechanism is usually of insidious of musculoskeletal injuries that occur in and in excessive stress and injury. Despite the onset and often unilateral on the dominant around the pubic symphysis and that share clarity of the mechanism of injury, the kicking leg in football. However, it is similar mechanisms of injury and common condition is still not well-understood as it important to note that 1/3 of patients clinical manifestations2. Another clinically can involve multiple factors including: describe a sudden tearing sensation. The relevant label is ‘groin disruption injury’ • stress reaction of the pubic symphysis pain is typically localised to the conjoint (Figure 1) consisting of sportsman hernia, due to high shear forces common with tendon but may involve the inguinal osteitis pubis, conjoint tendinopathy, cutting and side-stepping actions, canal laterally or the lower abdomen. The adductor tendinopathy and • conjoint tendon or in combination pain increases with sudden movements, entrapment3. with the adductors that spreads to the acceleration, twisting, turning and kicking subchondral bone, and may be provoked by coughing and Osteitis pubis • an imbalance or loss of synergy between sneezing. Symptoms may range from mild Osteitis pubis is a condition that involves the abdominals and adductor muscles. tenderness without palpable protrusion of the pubic bone symphysis, surrounding Clinical signs of osteitis pubis include the inguinal wall, to severe tenderness but muscle insertions and structures. Small groin pain while climbing stairs, running, not a palpable protusion (hernia).

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Musculotendinous Pubic region: adductor tendinopathy Figure 2: The inter-relationship of groin pain or ‘groin disruption injury’.

Nerve entrapment Bone Groin disruption injury Obturator nerve/ Pubic: osteitis pubis (athletic pubalgia) ilioinguinal nerve

Inguinal canal pathology Sports hernia: conjoint tendinopathy

Adductor tendinopathy and cause nerve entrapment. Obturator entrap- Human movement patterns affect the way The most common musculoskeletal ment pain can present as a deep ache in the the body functions and are implicated in cause of groin pain is a muscle strain of proximal adductor region that is referred to sporting injury. The goal of which the is the the medial thigh and worsens with exercise. is to maintain a state of equilibrium or most frequently injured. With repetitive Pain or numbness radiates down the inner homeostasis of the , muscles and loading this results in micro-inflammatory thigh, with associated weakness. The sporting techniques (e.g. walking, running, change in the para-symphseal bone which is obturator nerve arises from the ventral rami jumping and kicking) in an effort to prevent a precursor to osteitis pubis2. The adductors of L2 - L4 and descends through the psoas injury. Groin pain is a multifactorial dilemma act as primary stabilisers of the hip . muscle. The nerve continues to descend for the sports medicine practitioner. Adductor-related groin pain can be acute, through the obturator tunnel where it primarily as a strain of the myotendinous divides into an anterior and a posterior In the literature junction associated with a powerful branch. Pain typically has an insidious While an association exists between contraction (kicking actions) or can be onset and is localised to the adductor origin groin pain and sports involving kicking and chronic with tenderness over the adductor at the pubic bone. Imaging does not play a twisting activities when running, there is insertion at the pubic bone. Tendinopathy significant role in confirming the diagnosis, a lack of literature that investigates the in the groin is not acute, but a silent but may be important in excluding other effect of musculoskeletal biomechanics pathology. It presents with gradual pain diagnoses. Diagnostic measures include: in groin pain. This is most likely due to and stiffness in the groin region with start- • reproduction of pain by the the anatomical and biomechanical causes up activity, dysfunction is exacerbated by adductor muscles after exercise, which are complex and controversial. To sprinting, cutting, kicking and sliding tackle • electromyography and highlight the lack of established scientific actions. Clinical signs include tenderness on • a local anaesthetic block of the obturator research in the groin-lower extremity palpation at the origin of the adductors and nerve. biomechanics paradigm, the online data pain with resisted hip abduction. Examination findings are painful passive bases CINAHL, PsycINFO®, Medline®, abduction, painful/weak resisted adduction SPORTDiscus, Cochrane and Scopus Pelvic nerve entrapment and tenderness at the pubic tubercle. After were searched to retrieve all available Obturator neuralgia has been described exercise there is weak resisted adduction publications related to “groin and lower as a cause of exercise-related groin pain, and sometimes numbness in the lower/ extremity biomechanics in sport” for the particularly in athletes with a high repet- inner thigh. The condition represents a period January 1990 to December 2012. All ition of twisting and turning, and kicking. subset of groin pain in athletes that is databases were systematically searched The condition involves a fascial entrapment treatable by surgical means (fascial release). using the same keywords and text words. of the obturator nerve where it enters the allows most patients to resume Where relevant, ‘smart word’ searching thigh. Symptoms include medial thigh pain previous levels of activity. was used when the data bases did not that begins insidiously. The obturator nerve recognise the search words. Peer-reviewed is entrapped proximally where it enters the BIOMECHANICAL RISK FACTORS FOR GROIN journal publications with themes exploring thigh, but its cutaneous dermatome is at PAIN IN THE ATHLETE any facet of links between groin pain and the middle/lower medial thigh. The pain Biomechanics is the science of motion the lower extremity including leg length at the adductor origin points to adductor and how the musculoskeletal system differences and pelvic imbalances were enthesopathy that could consequently adapts to variations in human movement. examined.

362 A total of 676 from CINAHL (n=86), intrinsic risk factors for injury. The most symphysis at the front form a unit to hold PsycINFO (n=13), Medline (n=320), SPORT common of these factors are: the pelvis absolutely steady during any Discus (n=169), and Scopus (n=88) articles • foot misalignment, activity in any position which involves were identified with themes applicable • knee position, movement of the legs. If the pelvic girdle is to the search. The Cochrane database did • tibial angle, not balanced and firmly tied by all of the not result in any meta-analyses previously • femoral anteversion, ligamentous structures it cannot effectively examining the focus of the current review. • leg length discrepancy (which can allow movement of the legs without excess Further investigation harnessed a total of 12 encompass pelvic instability) and strain at the pubic symphysis joint. The articles with broad reference to groin-lower • a past history of injury. pubic symphysis joint may shear or separate extremity biomechanics and leg length Figure 3 identifies the main biomechani- causing pain. Instability of the pelvis and inequality studies associated with the lower cal risk factors of the lower extremity resultant groin pain has many contributing extremity in sport. However, no results were which have an association with groin factors, the common biomechanical entities obtained for specific research on the effects pain. For the sports medicine practitioner being: of anatomical biomechanics of the lower an understanding of biomechanics will • faulty foot and body mechanics, extremity and groin pain. There were case assist athletes when preparing for the • gait disturbances, studies with reference to the topic. goal of injury-free sport and when injury • poor running or walking mechanics, As the literature provides limited does occur, enabling sound rehabilitation • tight, poor hip range of motion due to consensus, much of the research into links principles. muscle stiffness in the , groin and between the biomechanics of anatomical , pathology and groin pain is gained from THE ROLE OF THE UNSTABLE PELVIS IN • muscular imbalances and clinical appraisal, case studies, surgical GROIN PAIN • leg length differences. reports and observations from the sports A well-balanced pelvis is paramount Thus a goal of athlete screening is to medicine community. Consensus has to optimal sports biomechanics as the identify the unstable pelvis and nullify been achieved that muscle imbalance or majority of sports played depend on a well- the causative factors that result in leg structural asymmetry is a key component balanced pelvis that requires the complex length inequality, reduced hip range of to sub-optimal biomechanical homeostasis, orchestration of different muscle groups, movement and adductor-abductor muscle which within the confines of clinical sports and joints. The sacroiliac joints imbalance (refer to malicious malalignment medicine are rated the most important at the back of the pelvis and the pubic syndrome). These entities contribute to functional and structural pelvic instability, compromising rotational stabilisation of the pelvis which is a critical factor in injury prevention and reoccurrence3. Pelvic asymmetry (core stability) LEG LENGTH INEQUALITY An imbalance between the lengths of legs is frequently overlooked in the evaluation of groin, low back and hip problems. Asymmetry of the legs is considered, in clinical sports medicine, to Malicious Groin disruption be a risk factor for postural compensations misalignment syndrome injury/athletic pubalgia Leg length inequality and injury. It generally can be classified into (knock ; foot (functional v structural) pronation; & the role of lower three categories: external rotation) biomechanics 1. Anatomical difference: a natural developmental asymmetry which is fixed following closure of the femoral and tibial growth plates. Other causes of a structural or anatomical Footwear difference include fracture, disease (ground surface; and complications of hip replacement age; suitability) surgery. 2. Apparent (functional) discrepancy: this is due to an instability of the hip-pelvis- low back, that allows the proximal to migrate proximally, or due to Figure 3: Relationship between ‘groin disruption injury’ and lower extremity biomechanics. an adduction or abduction contracture

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of the hip that causes pelvic obliquity, is uneven or too soft will also overload the types with high root density, generally the so that one hip is higher than the other. unstable pelvis. warmer climate grasses, creates greater When the patient stands, it gives the Important footwear characteristics for shoe-surface traction. Conversely ryegrass, impression of leg length discrepancy, injury prevention include: a cool climate winter grass, is likely to while the problem is actually due to • traction, create lower surface traction due to its fine musculoskeletal dysfunction. • cushioning, root density. Therefore a combination of 3. Combination of the first and second • fit and unstable pelvis and poor footwear selection type of leg length imbalances. • suitability relative to task as well as relative to ground surface is a risk factor for Consensus on what leg difference is lower-limb morphology. groin injury. However, this association has considered clinically significant varies in A common mechanism, but a poorly never been made scientifically. the literature. A review of the American understood one, is the interaction between Academy of Orthopaedic Surgeons foot-fixation and playing surface interface. Injury prevention literature shows that, in a study of 600 Data from various professional sporting When it comes to athletes, footwear is military personnel, 30% had a limb length organisations including the NFL (American the only form of player apparel that acts as imbalance ranging from 5 to 15 mm. This Football) indicates that per-team injury a filter between the ground surface and the was considered a normal variation6. Other rates are 27% higher for games played on body. It is this interaction that will directly reports indicate that anatomic leg-length artificial turf surfaces vs games played influence movement patterns of an athlete inequality is not clinically significant until on natural grass. Injury is also associated on a variety of surfaces (soft, hard, wet, dry the magnitude reaches 20 mm. Other with climatic conditions with an increase and undulating). For active populations such studies suggest as little as 5 mm difference in injury associated with warmer climates as military personnel, basketball players, is considered significant7. The effect of leg (e.g. pre-season training and early rounds runners and footballers, footwear has a length inequality on pelvic alignment is the of competition) and grass species. Grass direct correlation to injury. While a plethora altered biomechanics of the sacroiliac joint and pelvic girdle as a whole. An incorrect Ground reaction force (Fz ) pelvic tilt increases the risk of groin injury 1 as the pelvis is tilted too far forward causing musculoskeletal pelvic imbalance. The Motion control shoe effect of pelvic overload during sport cannot be underestimated in groin injury. Running 1000 and other exercise-related activities are associated with high ground reaction Ground reaction force (Fz ) forces (Figure 4). Such load forces with an 1 unstable pelvis, secondary to leg length 750 imbalance, at high speed running, kicking and twisting manoeuvres will compromise groin integrity. Cushioned shoe 500

FOOTWEAR AND GROUND SURFACES A common mechanism for lower extremity injury is the relationship between ground reaction force (N) Vertical 250 ground surface and footwear. Ground hardness refers to the effect the ground has on absorbing impact loads. The contribution of hard grounds to groin injury is associated 0 with high ground reaction forces at one end 0.0 0.1 0.2 0.3 of the ground spectrum and an unstable- Time (s) soft surface at the other. Ground reaction forces during running and jumping are Loading forces associated with exercise: commonly measured to range from 2 to 10 • Walking: x1.5 body weight times body weight (Figure 4). Hard ground • Running: x2-3 body weight • Jumping: x4-8 body weight provides greater peak reaction forces and are associated with injury risk especially in those sports that involve running, jumping, Figure 5: Differences in load attenuation when running in firm shoes on hard surfaces vs side-stepping and other load-bearing cushioned footwear on hard surfaces. Figure adapted from Ferris DP, Liang K, Farley CT. exercises. However, just as hard surfaces Runners adjust leg stiffness for their first step on a new running surface. J Biomech 1999; are a risk factor, a ground surface which 32:787-794.

364 contribute to a number of sporting outcomes Figure 5: Malicious misalignment such as performance, traction, comfort syndrome: internal femoral torsion, and injury. It is therefore imperative that internally rotated knees, tibial any injury prevention and management bowing and hyper-pronated feet. programme take into account individual tailored footwear prescription and that the type of footwear used be specific to ground conditions.

Malicious misalignment syndrome The relationship between groin pain and malicious misalignment syndrome is one of compensation. ‘Malicious misalignment syndrome‘ is characterised by excessive internal rotation of the hips and femur, knock knees, tibial bowing and hyper- pronated feet. The condition is commonly associated with patellofemoral dysfunction and anterior knee pain. However, the implications of the biomechanics of this syndrome to groin pain should not be underestimated. Accepted dogma indicates the importance of pelvic stability to prevent injury and guard against reoccurrence3. Logically, misalignment of lower extremity of data highlights the benefits of footwear principle of maintaining homeostasis of foot biomechanics will contribute to an to injury prevention, often footwear is function is the need for a close association unstable pelvis. A probable mechanism an area of sporting preparation which is between foot and shoe motion. Over the is an internally rotated lower limb with not factored into the injury prevention past 20 years, research has substantiated the hyperfoot pronation. The foot-ankle motion paradigm. Not only does the type of surface neurophysiological responses of footwear to will cause the legs to rotate and the pelvis used on various surfaces potentially pose an individual whereby individuals are likely to tilt forward straining the sacroiliac injury risk, but the relationship between to adapt running styles due to different joint. Where asymmetrical leg rotations or foot types (pesplanus, pescavus, hyper- shoes, foot-leg biomechanical imbalances asymmetrical foot pronation exists, there pronated, supinated) and footwear is an and lower extremity muscular tuning. will be asymmetrical loading of the right important criterion for injury prevention. Furthermore, without tailored footwear and left hemi-pelvis that contributes to The individualism of foot shape and foot prescriptions, a close association between pelvic instability. biomechanics adopting generic footwear the fit of a foot and an athletic shoe does not The pathomechanics of ‘malicious prescription policies, where one footwear exist. These features will have implications misalignment syndrome’ for the athlete is style applies to all in a team or where the for movement efficiency, injury prevention the alteration to running stride. Over time athlete selects footwear based on personal and performance enhancement ideals the demands of an unbalanced running bias, is poor sports medicine. An important of athletic footwear. Thus footwear will stride causes the adductor muscles to tighten, limiting external hip rotation, shortening and tightening of and an anterior pelvic tilt. The result is increased spinal curvature and continuous tension on the Footwear is the only muscles in the lower back, causing elements of the musculoskeletal system to function at unnatural angles to each other. In turn player apparel that acts the sacroiliac joint and pubis symphysis are prone to repetitive weakening and micro as a filter between the instability of the osteochrondral junctions of the pelvis, pelvic instability and eventual injury. ground and body Unilateral weight-bearing is a necessary requirement of closed-chain sporting

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activity for walking, running and kicking increases the load forces of the pelvis, players was decreased significantly from actions. Logically, this normal sequence especially at the pubis symphysis. baseline12. of intermittent single leg loading and unloading results in increased loading at Muscle imbalance THE ROLE OF PODIATRY IN THE the hemi-pelvis. If the pelvis is stable, these As a consequence of restricted hip MANAGEMENT OF THE ATHLETIC GROIN demands can be catered for. However, when joint range of motion, imbalances of the PAIN the pelvis is unstable the potential for adductors and abductor muscle groups occur. The role of podiatry in the management athletic chronic groin injury is enhanced Differences in muscular strength between and prevention of groin injury necessitates where restricted hip joint motion exists the adductor and abductor muscle groups a comprehensive understanding of the role and imbalances between the adductors and results in a lack of mechanical advantage for of lower extremity biomechanics in groin abductors occur. the groin as a whole. The primary function pathology. For enhanced patient outcomes, of the adductor muscle group is adduction co-operation between the , Hip range of motion of the thigh (open chain motions) and surgeon, physiotherapist and podiatrist Over the past 30 years there has been stabilisation of the lower extremity and provides a comprehensive management an ever-increasing body of knowledge pelvis in closed chain motion. Reviews of hip plan for the athlete. Stabilisation of the associating restricted hip range of motion muscular weakness in athletes suggest that pelvis requires integrity of the adductor and groin injury. In an early study of 180 adductor muscle strength is linked to the muscle group and the pubis symphysis. footballers, decreased hip abduction range incidence of groin strains. A study conducted The effect of alignment of the feet, legs of motion was linked with subsequent in ice hockey players found a relationship and pelvis is significant to ensuring pelvic groin strains, compared with uninjured between low hip adduction strength and stability. Injury to the pelvic and lower limb players8. A more in-depth investigation of groin strains11. In the players who sustained muscles, tendons and joints will disrupt 306 professional footballers also concluded a groin strain, pre-season adduction/ normal hip mechanics and lead to an that decreased range of hip abduction was abduction strength ratio was lower on the increased risk of adjacent injury. Podiatric a significant risk for groin injury9. Similar side that subsequently sustained a groin screening of the pelvis by assessing lower results were obtained in a study of Aust- strain (compared with the uninjured side). extremity biomechanics and foot posture ralian Rules footballers conducted over two Furthermore, hip adduction/abduction will contribute to injury prevention and seasons. Players without previous history of strength ratios were significantly different assist in rehabilitation of groin injuries. The groin injury who displayed reduced total hip between a non-injured and injured group of assessment of the lower extremity includes: joint range of motion progressed to chronic professional athletes in the National Hockey groin injury10. The pathomechanics of poor League. These results were reproduced in a 1. Clinical observation, gait analysis and hip range of motion is not only the effect 2012 study of 86 elite underage Australian review of plain film . of shortening the adductor muscle group, footballers which indicated that athletes A comprehensive patient evaluation which loads the insertion and predisposes, with groin injury exhibited hip adductor provides the clinician with an under- especially adductor longus, which is most muscle strength deficiency both before standing of the biomechanics which commonly injured during sporting activity, and during the onset of groin injury. The contribute to groin pain. Examination but the reduction on hip range of motion mean hip adductor muscle strength of these requires both weight-bearing postural

366 Figure 6: Anteroposterior X-ray of pelvis with 6 left leg raised (‘flamingo’ view) indicating Sacro-iliac joint dysfunction macro-instability (widening) of the symphysis illustrated by separation which will pubis and slight superior migration of left manifest as a pelvic instability pubic bone when compared with right. Misalignment of femoral heads Figure 7: Relationship between pelvic indicating drop of the right hemipelvis, alignment/ground surfaces and footwear indicating leg length inequality selection.

to distinguish true leg length discrepancy from apparent leg length discrepancy. In such a situation, CT leg length scans will provide an accurate diagnosis between anatomical and functional leg length difference. For assessment of the pelvis, sacroiliac dysfunction and bone pathology weight-bearing anteroposterior X-rays of the pelvis and ‘flamingo’ stress radiographs are used. Flamingo views are valuable as they quantify pubic instability, specifically Gross separation of the fibrocartilaginous joint the amount of symphyseal displacement. between the pubic rami and drop of the right pubis Measures greater than 2 mm are termed to highlight injury to pubis symphysis macro-instability (Figure 6).

2. lifts and foot orthotics UNSTABLE Mandatory requirements: STABLE 7 Heel raises, foot lifts and shoe PELVIS 1. Podiatry assessment: PELVIS heel raises/foot orthotics modifications balance a biomechanically 2. Physio rehabilitation inferior pelvis or level a tilted hemipelvis 3. Repeated groin screening due to an anatomical or functional short leg, reduce the shortening associated with a leg length difference and improve Cushioned shock absorbing gait efficiency. Heel lift utilisation, shoes e.g. moulded round however, will only address one aspect Hard stud football boots/ surface short cleats of lower limb instability. Foot orthotics are often required to optimise foot-ankle biomechanics (hyper-pronation, pesplanus, Player choice with athlete ankle equinus), assist with compensatory Ideal ground biomechanical motions of tibial bowing and genu valgum considerations for optimal surface (knock knees) and neutralise the effects of performance malicious misalignment syndrome. For the clinician managing groin injury generally, a Soft Motion control combination of heel raise and foot orthotics surface high traction shoes e.g. is used in combination. screw-ins football boots/long cleats 3. Footwear The use of prescription footwear is also an important component of the podiatric and non-weight-bearing examination. Measurements of leg-length discrepancy management of groin pain. Tailored Static stance evaluation will enable an are obtained prone or lying down in non- footwear programmes significantly overall evaluation of posture, identify foot weight-bearing positions. While providing lower injury rates in sport. Evidence from imbalances and assess pelvic asymmetry. a generic overview of possible leg length intervention studies in codes of football Gait observations, both shod and barefoot, inequality, it is an unreliable measure as indicate a direct correlation between enable the clinician to better appreciate muscle imbalance will affect the results. improved individual comfort, reduced injury the effect of groin injury on locomotion and During weight-bearing standing evaluation, and improved performance. Figure 7 offers whether the lower extremity biomechanics if there is a pelvic tilt due to a possible leg clinical guidelines to footwear and ground can be addressed by footwear and orthotic length difference then weight-bearing X-ray surface management for the stable and interventions. is the investigation of choice. It is important unstable pelvis.

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Figure 8: Example of cleated football boots for soft/unstable surfaces.

When an unstable pelvis is diagnosed in the athlete, the type of footwear selected will differ depending on the ground surface. When the surface is soft and unstable, such as those encountered with natural turf in winter climates, the aim is to provide a stable lower extremity to ensure musculoskeletal homeostasis. This is achieved by increasing the coefficient of friction and thus traction between the athlete and the ground surface. Thus for football, suitable footwear styles References include football boots with screw-in studs 1. Falvey EC, Franklyn-Miller A, McCory PR. 9. Arnason A, Sigurdsson SB, Gudmundsson and long cleats. The groin triangle: a patho-anatomical A, Holme I, Engebretsen L, Bahr R. Risk When ground surfaces are firm, the approach to the diagnosis of chronic factors for injuries in football. Am J Sports aim of managing and rehabilitating pelvic groin pain in athletes. Br J Sports Med Med 2004; 32:5-16. instability is to attenuate load to the lower 2009; 43:213-220. extremity and thus dampen the forces of 10. Verrall GM, Slavotinek JP, Barnes PG, 2. MacMahon PJ, Hodnett PA, Koulouris GC, Esterman A, Oakeshott RD, Spriggins running and multi-directional movements. Eustace SJ, Kavanagh EC. Hip and groin AJ. Hip joint range of motion restriction Suitable footwear therefore includes pain: radiological assessment. The Open precedes athletic chronic groin injury. J Sci cushioned running shoes and, in football, Sports Medicine Journal 2010; 4:108-120. Med Sport 2007; 10:463-466. moulded, turf-style shoes. 3. Garvey JF, Read JW, Turner A. Sportsman 11. Tyler TF, Nicholas SJ, Campbell RJ, McHugh CONCLUSION hernia: what can we do? Hernia 2010; MP. The association of hip strength and Chronic groin pain is a common problem 14:17-25. flexibility with the incidence of adductor in athletes. The multifactorial nature 4. Kavanagh EC, Koulouris G, Ford S, muscle strains in professional ice hockey and the various anatomical structures McMahon P, Johnson C, Eustace SJ. MR players. Am J Sports Med 2001; 29:124-128. that contribute to groin pain have made imaging of groin pain in the athlete. 12. Hides JA, Brown CT, Penfold L, Stanton WR. the condition difficult to prevent and Semin Musculoskelet Radiol 2006; 10:197- Screening the lumbopelvic muscles for a manage. Early detection and intervention 207. relationship to injury of the quadriceps, are the keys to optimal management and 5. Koulouris G. Imaging review of groin pain , and adductor muscles prevention of chronic injury. The current in elite athletes: an anatomic approach to among elite Australian Football League lack of reliable clinical indicators (i.e. clinical imaging findings. AJR Am J Roentgenol players. J Orthop Sports Phys Ther 2011; and functional screening tests) to assess 2008; 19:962-972. 41:767-775. the likelihood of developing chronic groin 6. Ortho Info. Limb length discrepancy. From pain makes it difficult to establish effective http://www.orthoinfo.aaos.org/topic. Michael A. Kinchington Ph.D., M.Pod., M. prophylactic guidelines, but an astute cfm?topic=a00259 Accessed March 2013. Ex & Sports Science, F.A.A.P.S.M., F.S.M.A. clinician awareness of the potential risk 7. Knutson GA. Anatomic and functional Research Fellow factors will improve athlete management. leg-length inequality: a review and This review provides the clinician with an Australian Catholic University recommendation for clinical decision- understanding of the entity, focuses on the Sydney, Australia making. Part II, the functional or biomechanical risks associated with groin unloaded leg-length asymmetry. Chiropr Contact: [email protected] pain from a lower extremity perspective Osteopat 2005; 13:12. and introduces the role of podiatry as an effective adjunct to the multi-disciplinary 8. Ekstrand J, Gillquist J. The avoidability of soccer injuries. Int J Sports Med 1983; groin management team. 4:124-128.

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