Sports-related groin pain or 'sports hernia'

INTRODUCTION — The term "sports hernia" is used to describe a condition characterized by groin pain, often in an athlete, in which there is no demonstrable hernia. The term is therefore a misnomer because there is typically no true hernia or defect in the groin or abdominal wall [1].

A variety of other terms have been used interchangeably to describe this condition, including "sports-related groin pain" (preferred), "sportsman's hernia," "hockey groin," and "athletic pubalgia." The condition has become more widely known as a growing number of professional athletes have undergone surgical treatment of the condition.

Sports-related groin pain was described initially in Europe but has become a more common diagnosis in the United States among athletes involved in high-intensity sports. It is not confined to professional athletes, however, and has been described in youth, college, and recreational athletes.

The diagnosis and treatment of sports-related groin pain are discussed here. True groin hernias (eg, inguinal and femoral hernia) are reviewed separately. (See "Classification, clinical features, and diagnosis of inguinal and femoral hernias in adults" and "Overview of treatment for inguinal and femoral hernia in adults".)

DEFINITION — The basic definition of sports-related groin pain (ie, sports hernia) is any condition causing persistent unilateral pain in the groin without demonstrable hernia. This definition assumes that no other significant gastrointestinal or genitourinary condition is present that might account for the patient’s symptoms. Sports-related groin pain, therefore, is a clinical diagnosis.

Although inguinal hernia is clinically absent, in virtually all reported case series, a small number of occult hernias are identified at the time of surgical exploration.

There is ongoing debate about the terminology used to describe this condition [2,3].

ETIOLOGY AND RISK FACTORS — Sports-related groin pains typically result from chronic, repetitive trauma or stress to the musculotendinous portions of the groin. It often develops in an insidious fashion without sudden or dramatic pain. Symptoms typically come from overuse of the lower abdominal musculature (eg, rectus abdominus) and the muscles of the upper thigh (eg, adductors).

Sports-related groin pain is more common in males than females and is more common with sports such as hockey, soccer, rugby, and American football, in which athletes frequently move forcefully from a forward-leaning position (ie, standard "athletic stance") into one of extension. Extension of the anterior trunk, abduction of the hip (stretching of adductor muscles), or both is commonly described. As such movement occurs in numerous athletic endeavors, virtually all sports can produce sports-related groin pain. In addition, any sport that involves high-speed change of direction (eg, sprinting, cutting, turning) or torquing of the groin (eg, kicking) can contribute to development of the condition.

Risk factors for the development of sports-related groin pain were investigated in high-performance hockey players [4]. Subjects were evaluated for degree of off-season training, peak isometric adductor torque, total hip abduction flexibility, prior injury, degree of National Hockey League (NHL) experience, and measurement of skate blade hollowness. Variables predictive of groin injury were limited to players with prior injury, those who did not condition aggressively during the off-season, and veteran (older) players. Similar findings have been reported in other series examining a wider variety of athletes.

A retrospective review of over 200 professional American football players at the National Football League (NFL) scouting combine reported an association between low vitamin D levels and a history of sports-related groin pain and lower extremity muscle strains [5]. Low vitamin D may increase susceptibility to injury or muscle dysfunction. (See "Vitamin D and extraskeletal health", section on 'Muscle function'.)

PATHOPHYSIOLOGY AND CLINICAL ANATOMY — Variable pathologic abnormalities have been described in athletes with sports-related groin pain, all related to repetitive strain in the inguinal and pubic regions. Early reports suggested that the primary culprit was a tear of the external oblique aponeurosis (figure 1 and figure 2), leading to injury of the ilioinguinal nerve as it coursed through this area (figure 3) [6]. Subsequently, some experts have emphasized other possible causes, including [7,8]:

●Imbalances in strength between the rectus abdominis and adductor muscles, leading to injury at the aponeurosis of the oblique muscles

●Defect or weakness within the posterior inguinal canal

●Compression of the genital branch of the genitofemoral nerve, possibly due to weakness of the posterior inguinal canal (the author feels this is a less likely explanation)

During intense athletic activity, the muscles, tendons, and ligaments of the inguinal region are continually under stress and in turn exert substantial stress on the pubic bones and joint and related structures. Relative differences in the strength of the opposing forces exerted on the pubic region from the rectus abdominus above and the adductor muscles below is a possible cause for the pathologic changes seen with sports-related groin pain. In addition, repetitive trunk extension, hip abduction, and torso rotation create shear forces that can contribute to injury at the insertion of the rectus abdominis and adductor longus and may subsequently lead to injury of the posterior abdominal wall.

Other conditions thought to contribute to patient symptoms include osteitis pubis (inflammation of the pubic tubercle) and musculotendinous strain of the adductor muscles (figure 4) [9]. A study from the United Kingdom performed exploratory inguinal surgery on 35 patients with groin pain [10]. Nearly two-thirds of patients had a tear in the external oblique aponeurosis. Other patients were found to have torn conjoined tendons, small direct hernias, weak posterior wall, and lipomas of the spermatic cord.

HISTORY AND PHYSICAL EXAMINATION — The diagnosis of sports-related groin pain is made in a patient who participates in high-intensity sport and has typical symptoms with no evidence of hernia or other common injuries (eg, isolated adductor muscle strain) or conditions on history and physical examination. (See 'Diagnosis' below.)

Symptoms vary in their nature, intensity, duration, and frequency [7,8]. Pain at the groin or the area of the pubic tubercle is the predominant symptom. While most patients describe pain that developed gradually over weeks to months, some may describe an acute injury during athletics involving extreme trunk extension and hip abduction. Pain may radiate to the lower abdomen, particularly the area of the rectus abdominus insertion or the adductor tendon origin. It is often exacerbated by sudden increases in intra-abdominal pressure, as can accompany coughing or sneezing. Straining at defecation can also cause mild discomfort. Athletes may describe increasing pain while playing their sport, particularly when performing movements involving the lower abdominal and adductor muscles. Frequently, symptoms can be reproduced by simple maneuvers such as performing sit-ups or crunches [11].

Examination of the groin fails to detect the bulge or "silky" sensation of an impulse with coughing or straining that is typical of an inguinal hernia. Palpation of the superficial (external) inguinal ring via the scrotum, as performed to assess for a hernia, typically reveals point tenderness and dilation of the ring and provokes symptoms (figure 5) [12]. Tenderness may be present at the pubic tubercle where the conjoint tendon inserts or over the deep (internal) inguinal ring (figure 1) or at the origin of the adductor.

Further examination is performed with the patient in a supine position with their knees bent and heels together (so-called "frog position"). If the patient has pain or discomfort with forced adduction against the examiner's resistance, this too is suggestive of a sports-related groin pain. Additional tests include putting the athlete into positions of stress from their particular sport and applying resistance to see if this reproduces symptoms. An example would be to have a soccer player assume the position of kicking across their body and resist the internal rotation and adduction of the lower leg.

DIAGNOSTIC IMAGING — Imaging is not necessary for patients whose diagnosis is clear and who will be managed nonoperatively with physical therapy. In general, most surgeons order an imaging study prior to surgical treatment; the choice of magnetic resonance imaging (MRI) or ultrasound depends upon local expertise and availability. Anteroposterior (AP) plain radiographs of the pelvis are generally not helpful for the diagnosis of sports-related groin pain but, if obtained, may demonstrate boney abnormalities consistent with osteitis pubis.

Magnetic resonance imaging — MRI studies with a large field view that includes the pubic symphysis can provide important information about the extent and location of injury [13,14]. In patients with sports-related groin pain, MRI may reveal abnormalities of the pectineus and rectus abdominus [15-17]. According to one small observational study, MRI demonstrates 68 percent sensitivity and 100 percent specificity for rectus abdominis tendon injury [18]. MRI may also reveal changes in the conjoint tendon, inguinal ligament, and adductor longus tendon consistent with injury.

Potentially confusing MRI findings include marrow edema of the symphysis pubis (osteitis pubis) and fluid in the symphysis pubis, as these findings occur in some patients who do not appear to have pain related to the symphysis.

Ultrasound — Ultrasound, particularly dynamic ultrasound, probably offers the best method for diagnosing abnormalities in the inguinal canal. Musculoskeletal ultrasound examination of the hip region and ultrasound for the diagnosis of inguinal hernia are reviewed separately. (See "Musculoskeletal ultrasound of the hip" and "Classification, clinical features, and diagnosis of inguinal and femoral hernias in adults", section on 'Diagnostic evaluation'.)

Ultrasound is operator dependent, and the diagnosis of sports-related groin pain requires a radiologist or clinician with expertise [19,20]. Ultrasound examination of the floor of the inguinal canal by an experienced ultrasonographer may demonstrate occult hernias and occasionally demonstrates conjoint "tendonitis," attenuation of the conjoint tendon, and indirect evidence of tendinopathy of the adductor longus (image 1 and image 2) [21,22]. Ultrasound may also reveal tearing of the aponeurotic plate of the rectus abdominis and adductor longus and irregularity and spurring of the body of the pubis (image 3).

If osteitis pubis is considered in the differential diagnosis, technetium-99m bone scan may be obtained and generally demonstrates increased uptake in the region of the pubis and loss of the "clear stripe" that separates the bony margins of the symphysis. Such findings are not present with sports-related groin pain.

DIAGNOSIS — Sports-related groin pain is a clinical diagnosis made based on a suggestive history and examination findings after other causes of groin pain (eg, inguinal hernia, isolated adductor muscle injury) have been ruled out. The majority of patients are young males participating in high-intensity sports (eg, ice hockey, soccer, rugby, American football) that place repetitive strain on the musculotendinous structures of the inguinal region and who complain of groin or pubic area pain. Palpation of the superficial (external) inguinal ring via the scrotum, as performed to assess for a hernia, typically reveals point tenderness and dilation of the ring and provokes symptoms.

Given the limited evidence available, the diagnosis of sports-related groin pain can be approached several ways. According to the British Hernia Society, any three of the following five clinical findings may confirm the diagnosis [23]:

●Localized tenderness at the pubic tubercle at the insertion of the conjoint tendon

●Tenderness over the deep inguinal ring

●Dilatation and/or pain at the external inguinal ring without obvious hernia

●Tenderness at the origin of the adductor longus tendon

●Diffuse pain in the groin, perineum, or inner thigh

In many clinics, patients with three or more of these findings are referred to a surgeon with experience treating sports-related groin pain. Clinicians with expertise in musculoskeletal ultrasound may first perform an examination looking for signs consistent with the diagnosis. However, many patients have vague presentations without three or more of the listed signs. If such a patient fails to improve with appropriate nonoperative care, including rehabilitation of the abdominal and adductor muscles, diagnostic imaging or surgical consultation is obtained.

DIFFERENTIAL DIAGNOSIS — The differential diagnosis for sports-related groin pain includes the large differential of groin pain generally (table 1). Included in this differential are osteitis pubis, distal abdominal rectus strain or avulsion, adductor tenoperiostitis, and tear of the adductor longus. Medical and surgical causes include epididymitis and inguinal hernia. Relatively uncommon but important diagnoses to consider include testicular torsion and enlarged inguinal lymphadenopathy (possibly associated with infection or neoplasm). A simple adductor muscle strain (ie, "groin pull"), or a true hernia that was not noted previously on physical examination, should be considered.

Several factors may complicate the diagnosis of sports-related groin pain. One or more pathologic findings may be present, groin- and hip-related conditions may coexist, or symptoms from one or more causes may overlap. The approach to undifferentiated groin pain in the athlete and active adult is reviewed in detail separately. (See "Approach to hip and groin pain in the athlete and active adult".)

When differentiating between sports-related groin pain and adductor muscle strain, a common athletic injury, symptom duration is one useful factor. If symptoms fail to improve with several weeks of rest from sport and standard conservative measures (eg, ice, compression with elastic bandage, elevation when at rest), adductor strain is less likely. Conversely, symptoms from sports-related groin pain recur as soon as the patient resumes athletic activity. Patients with adductor muscle strain or tendinopathy are more likely to experience focal pain when lifting their leg while climbing stairs or when stretching their adductors or squeezing their thighs together (forceful adduction). Symptoms from sports-related groin pain are more prominent when performing abdominal crunches, and pain radiates down the upper, inner thigh. (See "Adductor muscle and tendon injury".)

TREATMENT

Initial treatment — Following any acute injury, the application of ice packs to the affected area three to four times per day for approximately 10 minutes at a time is beneficial. Treatment with ibuprofen or another nonsteroidal antiinflammatory medication reduces pain and acute inflammation. Once acute symptoms subside, gentle rehabilitation exercises performed under the guidance of a knowledgeable physical therapist, athletic trainer, or other clinician may be helpful. Rest is a simple but important part of initial care. Patients who insist on continuing athletic endeavors soon after injury take considerably longer to heal any injury to the groin.

Often, the simple initial interventions described here do not provide long-term relief. Typically, after a brief period of rest, the athlete experiences a recurrence of symptoms when they renew their activity. Treatment options for these individuals include physical therapy and surgical repair. Many professional athletes find it difficult to take the prolonged rest necessary to heal the groin completely and opt for surgery.

Physical therapy — For high-performance athletes seeking a quick return to sport, the delay caused by a lengthy period of rest or physical therapy is often unacceptable, and thus, surgical repair has been their preferred treatment approach for sports-related groin pain. However, several observational studies suggest that for athletes willing to participate in a well-designed physical therapy program focused on increasing the strength and mobility, and improving the coordination and mechanics, of the muscles of the pelvis, hips, and lower extremities, outcomes comparable to surgery can be achieved [24-26].

As an example, a prospective observational study of 205 athletes with anterior hip and groin pain (pain or tenderness at the pubic aponeurosis was the presenting finding in 64 percent) of at least four weeks duration reported substantial improvements in hip and groin function and strength, and in running mechanics, sufficient to enable 73 percent of athletes to return to pain-free play at a mean of 9.9 weeks [25].

Physical therapy is a reasonable approach for patients who can afford to resume sports or work activities at a slower pace. Patients who do not improve with a trial of conservative treatment that includes a well-designed physical therapy program, but who wish to resume their prior level of activity, should be referred to a surgeon.

Surgery — Surgical exploration and repair is the most common treatment for sports-related groin pain, although few controlled trials confirming the effectiveness of this approach have been performed. In one such randomized trial of 60 patients, including many high-level athletes, with chronic groin pain diagnosed as sports-related groin pain (minimum three months of symptoms), 27 of the 30 patients treated with laparoscopic surgery and mesh placement returned to full sport activity within three months of the procedure compared with 8 of 30 managed with physical therapy and other nonsurgical interventions [27]. At one-year follow-up, 29 of 30 surgical patients had returned to full activity while seven of the patients treated conservatively during the study period subsequently opted for surgery and also returned to full sport activity; the remainder of the nonsurgical patients continued to experience disabling symptoms.

Before proceeding to surgery, it is important to rule out isolated adductor muscle injury as the cause of symptoms. Adductor injuries are best treated with physical therapy, although in rare cases (eg, complete tendon rupture), surgery may be needed. (See "Adductor muscle and tendon injury".)

Surgical exploration can be performed either laparoscopically or open using an anterior approach. The former restricts the surgeon to simply placing prosthetic mesh in the preperitoneal space and dividing nerve fibers (specifically the genitofemoral nerve as it passes through the internal ring) [28,29]. Others, particularly within the European community, have advocated convincingly for a transabdominal preperitoneal approach [30].

The standard preperitoneal laparoscopic approach involves using polypropylene or polyester mesh, though biologic inserts have also been employed with good results [31]. A potential complication of mesh hernia repair, the development of infection, is discussed separately. (See "Overview of treatment for inguinal and femoral hernia in adults".)

Alternatively, an open anterior approach allows for greater precision in identifying the abnormality and in tailoring the corrective surgery to the specific pathophysiologic abnormality [6,10]. In most cases, anterior approaches will demonstrate injury to the aponeurosis of the external oblique with an associated injury to the ilioinguinal nerve. Neurectomy or neural ablation is often employed to minimize long-term persistent dysesthesia. Standard anterior hernia approaches are also used with good effect [32]. A mini-open incision sports-related groin pain repair has been described [33].

In a multicenter randomized trial involving 65 athletes (approximately one-half soccer players), no significant differences in long-term pain relief or return to activity were found between patients treated with open minimal suture repair (OMSR) compared with endoscopic extraperitoneal repair (EER), although pain resolved more quickly in patients treated with EER [34]. By three months, 25 of 31 patients in the OMSR group and 31 of 34 patients in the EER group had achieved full recovery, and nearly all patients were pain free.

In select patients, some surgeons report good results performing tenotomy of the adductor longus, but evidence is limited to small case series [35,36]. Tenotomy can be done either as an isolated procedure or in conjunction with a more traditional sports-related groin pain repair.

PREVENTION — Little, if any, research has been done to investigate prevention strategies for sports-related groin pain. Some experts advocate general core strengthening, but no specific exercise program has been studied. General exercises to improve core strength and endurance (eg, planks and side planks (picture 1)) and to develop strength and mobility of the hip musculature (eg, squats (picture 2 and picture 3 and picture 4)) would seem to be reasonable. (See "Practical guidelines for implementing a strength training program for adults".)

OUTCOMES — Available studies suggest that long-term improvement is seen in up to 90 percent of surgically treated patients, although relapses can occur in a small number [29,37]. The large majority of athletes return to play, and performance is not impaired by surgical repair [38-41]. However, evidence is limited to uncontrolled, observational studies. In addition, the reported results are likely contingent upon having access to a surgeon with expertise in the relevant procedures, as was the case in these studies.

Outcomes in reported series do not appear to vary with the surgical approach used [10,42]. However, only one prospective study involving 16 subjects has objectively evaluated strength outcomes following surgery and rehabilitation [43]. Its authors concluded that pain may reduce lower limb strength as a result of disuse atrophy or pain-related muscle inhibition, and that relief of pain following surgery and rehabilitation can improve performance.

Complications from sports-related groin pain repair appear to be uncommon. In an observational study of 5460 procedures, hematomas developed in 0.3 percent of patients, superficial surgical site infections occurred in 0.4 percent, and 0.3 percent of patients developed dysesthesias of the ilioinguinal, genitofemoral, and anterior or lateral femoral cutaneous nerves [37]. Dysesthesias resolved in one-half of affected patients within 12 months.

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Hip and groin pain".)

SUMMARY AND RECOMMENDATIONS

●Definitions – Unilateral groin pain is a common complaint of high-performance as well as recreational athletes. In the absence of a true hernia, other medical or surgical conditions (table 1), or common injuries (eg, adductor muscle strain), this condition may be referred to as sports-related groin pain or "sports hernia." (See 'Definition' above.)

●Etiology and anatomy – The cause of sports-related groin pain is multifactorial but often involves injury and disruption of the aponeurosis of the external oblique muscle with concomitant injury to the ilioinguinal nerve (figure 1). (See 'Pathophysiology and clinical anatomy' above.)

●Epidemiology and pathophysiology – Sports-related groin pain occurs most often in males who participate in high-intensity sports such as hockey, soccer (football), rugby, and American football. It is associated with repetitive strain of the inguinal and pubic regions, which can stem from repeated, forceful movements from a forward-leaning position (ie, standard "athletic stance") into one of extension (particularly of the anterior trunk), abduction of the hip (adductor muscles), or both. (See 'Etiology and risk factors' above and 'Pathophysiology and clinical anatomy' above.)

●Presentation and physical examination – Symptoms can vary in their nature, duration, and frequency, but the typical presentation is of an athlete who participates in a high-intensity sport and complains of persistent groin pain that developed over weeks to months. Pain may radiate to the area of the rectus abdominus insertion or the adductor tendon origin. Pain is often exacerbated by any sudden increase in intra-abdominal pressure (eg, coughing, sneezing). Frequently, symptoms can be reproduced by performing abdominal crunches. (See 'History and physical examination' above.)

Examination does not detect the bulge or "silky" sensation of an impulse with coughing or straining that is typical of an inguinal hernia. Palpation of the superficial (external) inguinal ring via the scrotum typically reveals point tenderness and dilation of the ring and provokes symptoms (figure 5). Tenderness may be present at the pubic tubercle where the conjoint tendon inserts (figure 1). Discomfort with adduction against the examiner's resistance is suggestive.

●Diagnostic imaging – Imaging is not necessary for patients whose diagnosis is clear and who will be managed with physical therapy. Dynamic ultrasound and magnetic resonance imaging (MRI) often reveal characteristic lesions, but sensitivity is limited. (See 'Diagnostic imaging' above.)

●Diagnosis and indications for referral – Diagnosis is made based on a suggestive history and examination findings after other causes of groin pain (eg, inguinal hernia, isolated adductor muscle injury) have been ruled out. Given the range of possible presentations, once other diagnoses have been ruled out and sports-related groin pain is suspected, it is reasonable to refer the patient to a clinician with experience diagnosing and managing the condition. (See 'Diagnosis' above.)

●Differential diagnosis – The differential diagnosis includes the large differential of groin pain (table 1). Included in this differential are osteitis pubis, distal abdominal rectus strain or avulsion, adductor muscle or tendon injury, and adductor tenoperiostitis. Medical and surgical causes include epididymitis, inguinal hernia, testicular torsion, and enlarged inguinal lymphadenopathy.

●Management – Often, good outcomes are achievable with a well-designed physical therapy program focused on increasing the strength and mobility, and improving the coordination and mechanics, of the muscles of the pelvis, hips, and lower extremities. When symptoms do not resolve with rest and appropriate physical therapy, we suggest surgical repair for athletes seeking to regain their preinjury level of performance (Grade 2C). For high-performance athletes unwilling to accept the lengthy delays in return to play required for appropriate rest and physical therapy, early surgical referral is appropriate. Both laparoscopic and anterior approaches have been used with equivalent outcomes. (See 'Treatment' above.)

●Outcomes – According to observational studies, long-term outcomes are successful in up to 90 percent of surgical patients with appropriate rehabilitation. (See 'Outcomes' above.)