SPORTS REHABILITATION 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 groin based medicine 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 pathologies coexist that can cause similar pain ranks only behind knee, anterior factors for groin pain. symptoms and the causation of injury cruciate ligament injury and bone fracture 3. Explore the role of podiatry 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 foot-ankle 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 hernia pubalgia or ‘groin disruption injury’. kicking, changing directions and tenderness of the pubic symphysis exacerbated by provocative examination techniques. Sports hernia Obturator nerve Sports hernia is a medially-located bulge entrapment in the posterior wall of the inguinal canal due to weakening of the abdominal wall3. This has been attributed to an injury of the conjoint tendon (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 (fascia transversalis), a weak point in the abdominal Osteitis pubis wall. The pathology 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 hip. The ment. Groin pain involves a number of dynamic tissue capacity for hypertrophic condition presents often, and has complex conditions involving the lower abdomen, 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 thigh 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 ‘athletic pubalgia’, a adds to the suboptimal biomechanics of developing a ‘sports hernia’. generalised term that refers to a spectrum the pelvis 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 obturator nerve • 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). 361 SPORTS REHABILITATION 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 strain 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 sports medicine which the adductor longus muscle 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 joints, 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 joint. 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 stretching 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