Abstract
A hip adductor strain is the most common cause of acute groin pain. Athletes who participate in sports that require cutting and sudden change of direction are at a higher risk for this injury. They typically occur from an eccentric contraction of the adductor muscles. Chronic injuries are also common and typically attributed to a combination of overuse with low strength or flexibility of this muscle group. Patients with hip adductor strains complain of sharp, stinging, or aching pain in the groin area that may radiate down to the anteromedial thigh. Symptoms are worse when they adduct and flex their leg at the hip. The squeeze test and the static resisted hip adduction test are specific examinations for this injury. Magnetic resonance imaging is the image modality of choice for evaluating this injury; however, ultrasound may also be useful in acute cases. Hip adductor strains are managed initially with rest, ice, compression, and anti-inflammatory medications to decrease swelling and inflammation. Then, a progressive rehabilitation program is initiated to restore basic functions. Finally, sports specific training can be implemented once strength and flexibility are recovered. The length of the rehabilitation program varies depending on the severity of the injury and the athlete’s demand for his or her sport. If symptoms do not resolve, a cortisone or platelet-rich plasma injection may be offered. For recalcitrant or severe cases, a surgery consult may be warranted.
Acknowledgments
I would like to thank Michael T. Ellerbusch, MD, for his contribution to this chapter.
| Synonyms | |
| |
| ICD-10-CM Codes | |
| M25.551 | Pain in hip right side |
| M25.552 | Pain in hip left |
| M25.5529 | Pain in hip unspecified |
| S76.211 | Strain of adductor muscle, fascia and tendon of right thigh |
| S76.212 | Strain of adductor muscle, fascia and tendon of left thigh |
| S76.219 | Strain of adductor muscle, fascia and tendon of unspecified thigh |
| M25.551/2/9 | Pain in hip right side/left/unspecified |
| S76.211A/D/S | Strain of adductor muscle, fascia and tendon of right thigh, initial encounter/subsequent encounter/sequela |
| S76.212A/D/S | Strain of adductor muscle, fascia and tendon of left thigh, initial encounter/subsequent encounter/sequela |
| S76.219A/D/S | Strain of adductor muscle, fascia and tendon of unspecified thigh, initial encounter/subsequent encounter/sequela |
| Add 7th character to S76 for episode of care | |
Definition
Hip adductor strain refers to an injury of the hip adductor muscles at the muscle belly, myotendinous junction, or tendon. It can present as an acute or chronic injury. The hip adductor muscles include the adductor magnus, adductor brevis, adductor longus, pectineus, and gracilis muscles ( Fig. 53.1 ). All of these muscles are innervated by the obturator nerve with the exception of the pectineus muscle that is innervated by the femoral nerve. Their functions include hip adduction as well as hip flexion. Adductor strain is the most common cause of acute groin pain in athletes. The adductor longus myotendinous junction is the most commonly injured site.
A prospective cohort study of the incidence of groin injuries during a 1-year period among Swedish male club soccer players reported that 8% of all injuries were in the groin area, and 52% of these were attributed to adductor muscle or tendon injuries. A similar incidence was reported in a study on Norwegian female elite soccer players, in which 9% of all injuries were hip or groin strains; 83% of these were acute injuries; and 17% were secondary to overuse. As for male ice hockey players, 3.2 strains occur per 1000 player-game exposures. In Australian rules football, there is an incidence of 3.3 groin strains per team per season, the second most common musculoskeletal injury after hamstring strain, and a recurrence rate of 21%. In addition, it is the third most prevalent injury after hamstring strain and anterior cruciate ligament tear, with 11.9 matches missed per team per season. A retrospective cohort study on 500 Australian Football League players indicated that 17% sustained a hip or groin injury during their junior years. Of these, 31% were secondary to a hip adductor strain or tear, and 17% were recurrent injuries. Recurrence of hip adductor strains have been reported as high as 32% to 44% in ice hockey and Australian football athletes. Adductor strains in elderly athletes older than 70 years of age occur at a slightly decreased incidence of 5%. The incidence and prevalence of hip adductor strains in sedentary patients are unknown.
Athletes who participate in sports that require cutting and sudden change of direction (e.g., soccer, ice hockey, Australian rules football, etc.) are at increased risk for this injury. Adductor strains may also occur from an eccentric contraction of the adductor muscles opposing the abductor muscles, as may be seen with an explosive lateral propulsion in ice hockey. Hip adductor strains have been attributed to low strength or flexibility of this muscle group. There is usually poor conditioning of the trunk and lower extremities, characterized by muscle imbalance among the pelvic stabilizing muscles, including the hip abductor and adductor muscles, as well as the core muscles and hip flexors. In addition, poor technique and overuse are risk factors for adductor strains. In rare instances, sacroiliac dysfunction may be associated with adductor injuries.
Adductor strains may be classified according to functional limitation on physical examination or pathologic injury on magnetic resonance imaging ( Table 53.1 ). The functional classification may or may not directly correlate with the tissue pathology seen on radiographic imaging. If the injury is localized at the tendon or myotendinous junction, it may also be described as an adductor tendinitis, referring to an acute injury with active inflammatory process, or as an adductor tendinosis, referring to a chronic injury that is causing functional limitations and does not have an ongoing inflammatory reaction. Since it may be difficult to classify the presence of an inflammatory process, tendinopathy is used frequently to refer to an adductor tendon or myotendinous injury with partial or complete loss of function that may be acute or chronic.
| Grade | Functional Classification | Radiographic Classification |
|---|---|---|
| 1 | No loss to minimal loss of function or mobility | Inflammation at the injured site with no tear |
| 2 | Partial loss of strength and mobility | Partial tear of the adductor muscle and/or tendon |
| 3 | Complete loss of function | Full tear of the adductor muscle and/or tendon |
Symptoms
Patients with hip adductor strains complain of sharp, stinging, or aching pain in the groin area that may radiate down to the anteromedial thigh. Symptoms are worse when they adduct and flex their leg at the hip, such as when they move the outside leg into a car. They usually report tightness in the groin or anteromedial pelvic girdle region. In injuries involving a partial or complete tear of the muscle or tendon, they complain of soft tissue swelling and bruising in the medial thigh. Chronic injuries may only hurt during physical activity or sports participation.
Physical Examination
The patient presents with tenderness to palpation in the groin region, most commonly over the adductor longus tendon or myotendinous junction distal to the origin of the muscle at the anterior surface of the pubis between the crest and the symphysis. In severe injuries, a defect may be palpated in the muscle representing a tear in the muscle or tendon. There can be associated ecchymosis, swelling, and tenderness of the surrounding soft tissue. Antalgic gait may be noted with ambulation secondary to pain or dysfunction. Single-leg standing and squatting may reveal Trendelenburg sign, excessive hip internal or external rotation, or genu valgus or varus.
Pain or weakness of the hip adductor muscle may be elicited with active resisted hip adduction, hip adduction and flexion, and hip flexion. Groin pain may also be reproduced with passive forced hip abduction, as well as with passive flexion, abduction, and external rotation of the hip (FABER test). The “crossover sign” may be used to determine if the adductor strain is moderate to severe and likely to cause functional impairment. This maneuver consists of reproducing the typical groin pain while performing any of the provocative maneuvers mentioned above in the contralateral side (i.e., FABER test, active resisted hip adduction, or passive hip abduction). The squeeze test and the static resisted hip adduction test are specific examinations for hip adductor muscles. During the squeeze test, the patient is in the supine position with feet on the table, hips flexed to 45 degrees, and knees flexed to 90 degrees. The examiner places a fist between the knees and asks the patient to squeeze the fist by adducting the hips bilaterally. The resisted hip adduction test consists of laying the patient supine with legs straight, positioning each leg at 15 degrees of abduction, and bilaterally resisting active hip adduction.
Functional Limitations
Patients usually have difficulty with walking, running, doing pivot turns, going up and down stairs, standing up from a sitting position, and vice versa. As mentioned earlier, getting in and out of a car is particularly painful. Sexual intimacy is frequently avoided due to the close proximity of the injury to the sexual organs and groin pain experienced as the adductor muscles contract in order to stabilize the pelvis.
Hip adductor strains present with significant functional limitations during sports participation and interfere with athletes’ optimal performance. They may report difficulty with propulsion in the lateral direction due to the eccentric contraction of the hip adductor muscles attempting to decelerate the leg stride, tightness in the groin region despite stretching, and loss of maximal sprinting speed, among other complaints. The biomechanics of movements involving the hip joint are consequently altered as the athlete tries to avoid experiencing pain. If left uncorrected, this adaption eventually leads to other injuries such as contralateral hip adductor strain, osteitis pubis, and sports hernia.
Diagnostic Studies
Initial evaluation of groin pain should include plain films to rule out bone pathology, such as hip osteoarthritis and neoplasm. Avulsion injuries of the symphysis pubis and inferior pubic ramus may also occur due to chronic overuse and manifest with adductor enthesopathy and osteitis pubis. Magnetic resonance imaging (MRI) is the optimal imaging tool to evaluate for groin and hip pathology, since it provides visualization of a large field and gives a three-dimensional view of the region with excellent soft tissue contrast resolution. It is particularly effective for diagnosing adductor muscle and tendon pathology. Fat-saturated, fluid-sensitive MR sequences in the axial-oblique and coronal plains are best for evaluating hip adductor strains ( Figs. 53.2 and 53.3 ). MRI also helps differentiate hip adductor injuries from other pelvic pathology, such as acetabular labrum tears and osteitis pubis.
