Athletes involved in contact sports are at risk for a variety of different hip disorders. Participation in athletic activities involving physical contact, such as football, rugby, and hockey, among others, places athletes at risk for both repetitive mechanical intra-articular pain and direct impact-based injuries. Common injuries in this patient population include traumatic instability, contusions and “hip pointers,” and fractures of the hip and pelvis.

Of all athletes, those participating in contact sports are perhaps at the highest risk for traumatic hip instability, including subluxation and/or dislocation (see Fig. 2). Specifically, athletes most likely to sustain an injury resulting in hip instability include those participating in football and hockey [10]. It remains unclear as to whether these athletes are predisposed to hip instability due to underlying FAI. In a report of three cases of posterior hip instability by Berkes and colleagues [11], all three patients were found to have evidence of acetabular retroversion, a cam lesion, an elevated alpha angle, a labral injury, and a posterior acetabular rim fracture. While the presence of the bony fracture and possibly the labral injury can likely be attributed to the initial instability event, the other associated findings are clearly unrelated to the injury, and the question remains: do such anatomical abnormalities predispose these athletes to hip instability? Philippon and colleagues [10] performed hip arthroscopy on 14 professional athletes at a mean time of 125 days following traumatic hip dislocation and found all patients to have labral tears. Nine of the 14 athletes had evidence of FAI with cam- and/or pincer-type pathology. Despite the mean time from dislocation to reduction being only 3.56 h, all patients were found to have chondral defects at the time of arthroscopy, again suggesting possible preexisting intra-articular pathology from underlying FAI.

Hip pointer injuries are also common in contact athletes. The term “hip pointer” refers to an injury resulting from direct blunt trauma to the iliac crest. This type of injury is typically sustained only during contact sports after a direct blow to the hip and causes substantial pain and often an inability to continue participation [6, 12]. The trauma from the direct blow leads to subperiosteal edema with subsequent hematoma formation and a contusion of the iliac crest itself. In these situations, the history is usually diagnostic as patients are able to recall the specific inciting event and also point to where the pain is. Usually, plain radiographs are sufficient to rule out fracture and further diagnostic imaging is unnecessary. These patients will benefit from a course of activity modification, ice, and compression to the area. Occasionally, these patients may be managed temporarily with injections of local anesthetic to allow them quicker return to play [13]. While treatment for hip pointers is almost exclusively nonoperative, patients with persistent pain may be evaluated with hip arthroscopy in order to assess for possible concomitant intra-articular injuries.

Avulsion fractures near the hip represent another diagnosis commonly seen in the contact athlete, though noncontact athletes can sustain these injuries as well. Avulsion fractures are more common in the adolescent patient population and are typically the result of a sudden forceful contraction of a muscle attached to the apophysis. These injuries can be sustained with both forceful concentric and eccentric contractions. Common sites of injury include the anterior superior iliac spine (sartorius, tensor fascia lata), ischial tuberosity (hamstrings), anterior inferior iliac spine (direct head of rectus femoris), lesser trochanter (iliopsoas), greater trochanter (abductors), and iliac crest (from external and abdominal obliques) [14, 15]. While these injuries can usually be managed without surgery, nonunion or malunion can become problematic. For example, Matsuda reported on a case of a traumatic anterior iliac spine apophyseal avulsion fracture leading to secondary symptomatic FAI that ultimately required arthroscopic surgery with anterior iliac spinoplasty [16]. In this case, the patient was also noted to have acetabular retroversion and a cam deformity, which highlights the importance of evaluating for concomitant impingement-related symptoms in this patient population. Traumatic avulsion fractures/injuries of the ligamentum teres have also become increasingly recognized, and arthroscopic surgery is sometimes warranted. In a series including 23 patients with traumatic ligamentum teres ruptures undergoing hip arthroscopy, Byrd and Jones noted an average improvement in modified Harris Hip Score from 47 to 90 [17]. Interestingly, despite advanced imaging, the diagnosis of ligamentum teres rupture was made preoperatively in only 2 of the 23 cases, and thus arthroscopy proved to be both diagnostic and therapeutic for these patients.

Athletes participating in sports that involve a substantial amount of pivoting are at increased risk for several specific hip injuries. Some of the more common sports involving pivoting include soccer, lacrosse, wrestling, Australian rules football, and field hockey. The amount of strain placed on the hip and pelvis during a forceful pivot motion can be significant, leading to multiple painful conditions, including FAI, athletic pubalgia, osteitis pubis, and muscle sprains secondary to overuse. The pivoting action itself is thought to translate force down the kinetic chain, causing a compensatory overload from the hip to the knee, ankle, and foot, potentially leading to injury in these areas as well. Athletes engaged in pivoting sports often develop hip pain localized to the groin. Given the complex anatomy in this region, the differential diagnosis in these patients is extremely broad. Common diagnoses include FAI, adductor muscle strains, and osteitis pubis. Other causes of groin pain in these athletes are summarized in Table 1.

Adductor muscle strains are common in the pivoting athlete patient population [18–22]. These injuries are typically referred to as groin strains and are most often encountered by athletes participating in ice hockey, soccer [23], and Australian football. Adductor strains are more likely to occur in athletes with decreased adductor strength relative to abductor strength, as noted by Tyler and colleagues [24]. Specifically, Tyler et al. examined 47 professional hockey players and noted that athletes were 17 times more likely to sustain an adductor strain if their adductor strength was less than 80 % that of the ipsilateral abductor [24]. In another study, decreased adductor strength as well as flexibility have been shown to be risk factors in athletes [19], though the study by Tyler did not find adductor flexibility (or lack thereof) to be a risk factor [24]. Osteitis pubis is another diagnosis commonly encountered in the pivoting athlete, with pain most often localized to the groin. Thought to be a chronic, overuse injury caused by overloading of the pubic symphysis and adjacent parasymphyseal bone, patients with osteitis pubis will eventually develop a bony stress reaction affecting the pubic symphysis and/or the parasymphyseal bone [25]. Arriving at this diagnosis can be challenging, as patients will often complain of vague groin pain with adduction-, rotation-, and flexion-type activities, but occasionally, patients will have pain directly over the pubic symphysis.

Athletic pubalgia, or sports hernia, has become an increasingly recognized diagnosis in the pivoting athlete. Occurring predominantly in men, athletic pubalgia is an occult hernia caused by weakness (or a tear) in the posterior inguinal wall. A variety of anatomical structures may be involved, including attenuation of the transversalis fascia, partial avulsion of the internal oblique muscle fibers at the pubic tubercle, and disruption of the body of the internal oblique muscle itself. The etiology is poorly understood but is thought to be related to repetitive twisting and turning at high speed, which places substantial stress on the inguinal wall musculature. Typical exacerbating motions in these athletes include trunk hyperextension and thigh hyperabduction [26, 27]. Patients with this injury often have pain relief with rest and symptoms only become apparent during exacerbating movements. Unlike other more classic hernia presentations, there is no palpable bulge or other clinically appreciable signs of hernia in these patients, making the diagnosis challenging. Patients will often have tenderness over the pubic tubercle, especially with resisted hip adduction and resisted sit-up motions.

Many of these athletes can have concomitant athletic pubalgia and FAI. It is unclear as to whether anatomical features of FAI predispose these patients to the development of a sports hernia. Certainly there is a relationship between limited hip range of motion, in particular flexion and internal rotation, and the development of symptomatic groin pain [28]. In these cases, it is imperative for the surgeon to appreciate the potential for underlying FAI, as both nonoperative and operative treatments aimed only at athletic pubalgia are unlikely to be beneficial [29, 30]. Hammoud and colleagues [31] reported on a series of 38 professional athletes with athletic pubalgia undergoing arthroscopic surgery for FAI. The authors noted 32 % of these athletes had previously undergone isolated surgical treatment for athletic pubalgia, with none of these patients returning to their previous level of competition after the index procedure. Following the arthroscopic procedure for FAI, 36 of 38 patients were able to return to their previous level of play at an average of 5.9 months postoperatively [31].

Overhead athletes are subject to the same subset of hip disorders commonly encountered in other athletic patient populations, including FAI. These athletes, however, may experience unique sequelae from FAI not typically found in other athletes, as alterations in their biomechanics often occur in a compensatory fashion up the kinetic chain, from the hip to the sacroiliac joint, spine, elbow, and shoulder. Thus, while many overhead athletes, including pitchers, quarterbacks, and volleyball players, present with elbow and/or shoulder injuries, some authors will argue that baseline hip pathology is ultimately responsible [32, 33]. The act of overhead throwing places a tremendous force on the hip at all stages in the pitching cycle. The biomechanics of the pitching cycle are complex, and while much attention is given to the force placed on both the shoulder and elbow, hip motion and stability also play a key role in stabilizing the shoulder/elbow and even generating ball velocity. In 2010, Robb and colleagues [34] examined 19 professional baseball pictures throughout the cycle with a focus on hip range of motion. The authors found a significantly decreased passive range of motion in the nondominant hip when compared to the dominant hip for all ranges. Further, the authors found that the total arc of rotation of the nondominant hand was correlated with ball velocity. They concluded that the motion disparity between the dominant and nondominant hips was correlated with various pitching biomechanical parameters [34]. Laudner et al. [35] found that pitchers have significantly smaller amounts of hip internal rotation compared to positional players and, as a result, rely more on energy created in the core and upper extremity to throw. This data suggests a correlation between upper extremity injuries in pitchers and abnormal hip kinematics (less range of motion).