Several studies have addressed both intrinsic and extrinsic possible risk factors.
The main intrinsic factor consists of the strength imbalance between the adductor and abdominal muscles, but also reduced flexibility, important asymmetry or dysmetria between the lower limbs, lumbar hyperlordosis, and sacroiliac or hip arthropathy are listed as intrinsic risk factors for the development of adductor and abdominal tendinopathy . Other extrinsic risk factors are incorrect athletic training, unfavorable conditions of the playground, and wrong sport equipment, above all footwear.
14.2 Clinical Assessment and Diagnosis
Because of the several anatomical structures in the groin area, the diagnosis is often difficult, and attention to differential diagnosis must be paid .
The physical examination should rule out a hypothetic inguinal or abdominal hernia, as well as the femoroacetabular impingement (FAI) with a concomitant labral tear or a pubic symphysis affection .
The most common clinical presentation is groin or lower abdominal pain, often associated with a pain irradiation to the medial aspect of the thigh, to the abdomen, or even to the perianal area .
Usually unilateral, pain starts after physical activity and moves progressively to the other side, often compromising everyday activities and social life. In advanced stages, even actions like sneezing, coughing, defecating, or sexual activity cause pain .
For a proper evaluation and a correct diagnosis, several factors must be taken into account.
Clinical evaluation is important to determine whether the cause is articular, musculotendinous, hernia related, or of combined origin .
Observation of the patient is chiefly important in order to evaluate the mobility of the hips on all planes, the plantar support, the hindfoot and forefoot structure, as well as the posture, the rachis mobility, the spinal curvatures, and the modified rotation of the pelvis, if present. In fact it is well demonstrated that the adductor tendinopathy is commonly correlated with lumbar hyperlordosis and anteversion of the pelvis . Furthermore, the clinician should observe the inguinal canal, the symmetry of posterior superior iliac spines with the patient in supine position, the knee axis, and the patellar orientation.
The palpation of some specific point helps to identify the most painful areas. The most frequently finding for adductor tendinopathy is tenderness along the tendon during passive abduction and resisted hip adduction in extension  (Fig. 14.3). Also rectoabdominal and iliopsoas tendon insertions are considerable typical painful points in this tendinopathy  (Fig. 14.2). Pain may be also evocated during the adduction or contraction of the abdominal muscles (Fig. 14.4), iliopsoas (Fig. 14.5), and rectus femoris (Figs. 14.6 and 14.7), while the clinician exerts counter resistance during passive stretching of the adductors and iliopsoas muscles .
Adductor muscle and tendon strain associated with medial thigh and anterior groin pain during resisted adduction and passive abduction
Rectus abdominis. Pain with resisted trunk flexion and localized tenderness to palpation
Iliopsoas strain: pain with hip hyperextension or resisted hip flexion at 90°
Rectus femoris strain: pain with resisted hip flexion and knee extension
Specific clinical tests are for the evaluation of the articular mobility and to identify more accurately the painful points: through these tests it is possible to prove the shortening of the anterior chain, the posterior chain, and the sacroiliac joint . Similarly, the peripheral neurological examination may be performed using the Lasegue test, the Wassermann test, the patellar and Achilles tendon reflexes, and the cutaneous sensibility. As regards the adductor muscles, it is mostly common to evaluate the isometric contraction against proximal or distal resistance, with flexed or extended legs, for the assessment of the abdominal muscles and the eccentric contraction of both the rectus abdominis and the oblique muscles.
The instrumental confirmation of the diagnosis consists of conventional radiographs, ultrasound, and magnetic resonance.
X-ray assessment is used to confirm the diagnosis and to exclude bone or coxofemoral joint disorders . Plain radiographs show the hips and pelvis symmetry and observe the tendon insertional areas and the bone structure. The anteroposterior weight-bearing view of the pelvis is particularly useful. It is not uncommon to locate hip osteoarthritis and modified limiting bone in the presence of groin pain . The flamingo stress views are also used to evaluate pelvic stability .
Ultrasound is the first-line imaging modality to assess musculotendinous structures, insertional tendon areas, ligaments, and all the soft tissues. It is useful to distinguish between an acute trauma and a chronic overload injury, and it may also individuate an inguinal hernia or any alteration of the posterior wall of the inguinal canal . Longitudinal and axial images are then compared to the contralateral side.
Magnetic resonance imaging (MRI) is used to investigate some morphological details, because of the elevated contrast resolution images. It is usually helpful to individuate bone marrow edema, insertional tendinopathy, and symphysis capsular disruption  (Fig. 14.8). Central disc protrusion is relatively common among soccer players .
MRI imaging: bilateral adductor tendinopathy associated with osteitis pubis
MRI is generally preferred over computed tomography (CT) in case of acute lesions; conversely, CT images are commonly used for calcific or insertional chronic tendinopathies because of its detailed evaluation .
The management of adductor and abdominal tendinopathies consists of multimodal measures, such as pharmacological therapy, physical rehabilitation, and instrumental procedures.
The rehabilitation period may be distinguished in acute phase, subacute phase, and return to sport. During the whole healing time, a neuromuscular taping may be applied in order to promote muscular relaxation and to protect the musculotendinous units from any overstretching .
In the acute phase, the most important goal is pain reduction, mainly through muscular relaxation. This may be obtained using local injections of NSAIDs, corticosteroids, supplements for muscles and tendons, or platelet-derived growth factor (PDGF) .
Rehabilitation starts with postural balance measures, such as global and site-specific stretching, decontracting massotherapy, mechanical and proprioceptive recovery, and global postural exercises. During this first stage, isometric strengthening of the abdominal and adductor muscles is advised.
In the subacute phase, concentric and eccentric exercises may be started to promote muscle strengthening, always paying attention to the cardiovascular system. Massotherapy is also useful to stimulate microcirculation and to reduce inflammation . Heat therapy, extracorporeal shock wave therapy, and laser therapy are the most commonly used instrumental treatments, since they effectively promote tendon enthesis regeneration . With the introduction of core stability exercises, it is possible to stimulate the synergic strengthening of the adductors, abdomen, and lumbar muscles . Running is gradually reintroduced, starting on the treadmill, without interrupting any instrumental therapy.