Introduction
Background
Hip overuse injuries such as tendinitis and bursitis occur commonly in active individuals who participate in running, cycling, and cutting sports such as football, hockey, soccer, etc.1, 2, 3, 4, 5, 6, 7, 8 These injuries can occur after an acute injury, such as an adductor strain from soccer, or present as a chronic pain, such as a hamstring tendinopathy from repetitive activities such as running. Training errors, biomechanical issues, and sudden increases in activity levels are also risk factors. In the adolescent age group, traction injuries such as avulsion fracture and apophysitis can occur and cause difficulties with training and performance.9
The investigation into the cause and treatment of hip overuse injuries can often be frustrating for clinicians and patients alike. Many musculoskeletal injuries can cause referred pain into the hip area, but so can intra-abdominal, gynecologic, urologic, and spinal disorders.1, 3, 4, 5, 6, 7, 8, 10
For excellent patient education resources, visit eMedicine's Foot, Ankle, Knee, and Hip Center, Sports Injury Center, and Sprains and Strains Center. Also, see eMedicine's patient education articles Repetitive Motion Injuries and Muscle Strain.
Related eMedicine topics:
Bursitis
Iliopsoas Tendinitis
Overuse Injury
Tendonitis
Trochanteric Bursitis
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Frequency
United States
Hip overuse syndrome is a relatively common condition, particularly in people who are physically active.
Functional Anatomy
The hip joint can be imagined as a ball and socket. The ball, called the femoral head, is seated within the acetabulum of the pelvic bone (the socket). Both of these bones are covered by articular cartilage, a lubricating and cushioning layer that helps to prevent damage to the underlying bones. Likewise, the labrum is a cushion of fibrocartilage deep within the socket that helps to aid articulation and provide further cushioning.
The hip joint is subject to strong forces (which can be multiple times the body weight) with all weight-bearing activities, from walking to running, as well as jumping and cutting sports. This is due to the long, lever-arm mechanism of the lower extremity, with the hip joint being the fulcrum. Thus, the hip joint is often the location of degenerative arthritis as people age.
The capsular ligaments of the hip joint, which act like ropes, are formed from thickened portions of the joint capsule, helping to keep the 2 bones together and aid in articulation. These ligaments provide stability and tension to the joint with movement.
Anteriorly, the rectus femoris, iliopsoas, gracilis, and sartorius muscles connect the pelvic bone to the femur and help aid in flexion of the femur, bringing the leg up toward the body. These muscles, along with the rest of the quadriceps muscles, which extend the knee, are the largest and most powerful muscles in the body, responsible for producing large concentric, isometric, and eccentric forces. Because of this, these muscles are subject to traumatic injuries and tears from sudden starts (concentric contraction), stops (eccentric contractions), and direct trauma, as well as overuse injuries from repetitive activities (microtrauma).
Medially, the set of 3 adductor muscles and the pectineus connect the inner aspect of the femur to the front and inferior aspect of the pelvis; contracting these muscles adducts the femur back to midline and across the body (ie, crossing the legs). From the outside, the tensor fasciae latae and biceps femoris (toward the back) aid in abduction, moving the legs outward from the body. Posteriorly, the semitendinous and semimembranous muscles (the hamstrings), the biceps femoris, and the large gluteus maximus extend the leg backward from the body.
The gluteus medius, another posterior muscle of the hip and buttocks, aids in internal rotation and abduction of the thigh. The piriformis, quadratus, and superior and inferior gemelli work in tandem to perform external rotation of the hip.
Sport-Specific Biomechanics
All of the previously mentioned muscle groups are subject to increased loads in athletic and recreational activity (see Functional Anatomy). Tendons, which attach muscle directly into bone, are structures that are subject to high tensile strength, meaning they must stretch as the muscles shortens, but they do not provide strength. Inflammation of a tendon from injury or repetitive stress is called tendinitis.
Several tendons are cushioned from the underlying bone by a lubricating and cushioning sac called a bursa. The largest bursa in the hip joint is between the iliopsoas muscle and the pelvic brim and is called the iliopsoas bursa. Between the tensor fasciae latae and gluteus medius muscles and the greater trochanter of the femur, a portion of bone that juts out laterally from the proximal femur, lies the greater trochanteric bursa. Any bursa within the body can be inflamed from repetitive stress of the overlying muscles, direct trauma, or a spreading infection.
The tendinous portion of the muscle has poor blood flow, so injury or stress at the attachment of the tendon onto the bone can lead to degeneration of the area. This degeneration is associated with the disorientation of collagen fibers, increased cellularity, and angiofibroblastic degeneration. Pathology examination of these tendons fails to reveal inflammatory cells or increased blood supply to the area. These "scars" within the tendon are difficult to treat because of decreased blood flow into the injured area.
In the pelvic bones of children, adolescents, and young adults, the tendons attach onto a secondary growing portion of bone. This connection between the larger pelvic bone and smaller secondary growth area is called the apophysis, and in this age group it is the weakest link from the musculature to the bone. Consequently, the apophysis can be the direct source of pain from irritation (apophysitis), or it can be broken apart by a strong force on the tendon and pulled away from the larger pelvic bone (avulsion fracture).
Avulsion fractures around the pelvis occur in prepubertal athletes as the result of an actively contracting muscle encountering abrupt resistance such as a misstep, rapid acceleration, or eccentric movements. The treatment of most smaller avulsion fractures is similar to the treatment of strains of the muscle-tendon unit.
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Clinical
History
Taking an appropriate history from a patient with hip pain is of paramount importance. The first focus should be on the patient’s account of the pain. If the pain was of an acute onset after an injury, the incident should be thoroughly described. Was there a snap or pop? Did it occur during acute acceleration or deceleration? What was the exact motion occurring during the injury (ie, foot planter, how was he/she hit, etc)? Was the athlete able to bear weight after the injury? Could he or she continue playing? These injuries often occur with a pop or snap, with a resultant sudden, severe, well-localized pain and immediate disability.
If the pain has been more long term, a review of the athlete's training methods, distances, and activity level should be explored. Does the pain start during the activity, or only afterward? Is there night pain? Is the pain better the next day or worse? Is the pain occurring earlier in the activity? Do any specific activities or movements increase the pain?
Ask the patient about a previous history of similar problems. Has there been any previous diagnostic testing or treatment?
To rule out more dangerous pathologies, always ask about night sweats, fevers, weight loss, or anorexia. Is there any history of stress fractures, menstrual irregularities, or amenorrhea?
To rule out abdominal sources of the hip pain, ask about nausea, vomiting, diarrhea, changes in stools, or the presence of blood in stools.
To help rule out spinal causes, ask about lower back pain; radiation of pain down the leg into the calf, foot, or toes; and numbness, tingling, or weakness in the leg or foot.
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Physical
It is important to do a thorough examination of the hip in order to establish any limitations or deficits that the patient may have. Along with a hip examination, an examination of the knee and lumbosacral spine is important to establish if the patient's hip pain is referred pain from these sites. A systematic approach of observation, palpation, checking range of motion (ROM), and strength testing is important.
Observation
Observe the patient from the front, back, and sides. Note any asymmetry, as well as how the patient’s clothing rests on the waist and hips. Then, observe the patient walking to see if one side is favored over the other. These observations can be helpful clues in focusing the examination, as well as in detecting signs of a leg-length discrepancy. Swelling and ecchymosis can be present with more severe strains, but these findings are often absent because the injured structures are deep in the hip.
Palpation
Along with bony palpation (see below), it is important to appreciate the patient's muscle tone as this may be an indicator of muscle strain or guarding against underlying pathology. Acute or chronic injuries lead to tenderness of the muscle and tendon. Spasm after an acute injury is common. Passive stretching and active contraction of the muscle is often difficult but can help to pinpoint the exact anatomic injury.
It is important to establish and palpate the following landmarks:
- Boney landmarks
- Anterior superior iliac spine (ASIS) – Sartorius and tensor fasciae latae
- Iliac crest – Gluteal muscle attachment
- Anterior inferior iliac spine (AIIS) – Rectus femoris attachment
- Greater trochanter – Vastus lateralis and gluteal muscles
- Posterior superior iliac spine (PSIS)
- Ischial tuberosity – Hamstring muscles
- Pubic ramus – Adductors
- Muscle landmarks
- Anterior – Quadriceps muscles
- Posterior – Gluteal muscles and hamstring muscles
- Medial – Adductor muscles
- Lateral – Iliotibial band and gluteal muscles
It is important to check both active and passive ROM of the hip to assess and establish limitations and barriers. Actual measurements will help to the clinician to monitor the patient’s progress over time.
- Rotation
- Hip rotation is evaluated by having the patient seated with the knee flexed at 90° and moving the foot from the midline. Internal foot movement equates to external hip rotation (60°) and external foot movement results in internal hip rotation (30°).
- Another way of measuring hip rotation is to have the patient lying on his or her back. Flex the hip 90º and internally and externally rotate the hip. Limitations of internal rotation occur most often with hip osteoarthritis, femoral head osteonecrosis, and stress fractures of the femoral neck.
- Flexion/Extension
- Hip flexion (120°) is assessed with the knee flexed, and hip extension (15°) is examined with the patient lying in the prone position with the leg kept straight and elevated.
- Abduction/Adduction
- Abduction (45-50°) and adduction (20-30°) are performed with the patient lying supine and using the ankle to move away (abduction) or toward the midline (adduction). Follow the ROM examination with strength testing, which is performed by applying resistance to the ROM discussed above.
- Pain and resistance to quadriceps stretching indicates injury at the proximal rectus femoris, such as a myotendinous strain or avulsion. An injury at the origin of the hamstrings will cause similar findings with a seated or lying straight-leg raise.
- Sensory
- The sciatic (motor and sensory) and the lateral femoral cutaneous (sensory) nerves are commonly responsible for pain or numbness around the hip. Sciatic nerve pain and numbness can occur in the posterior hip and thigh with or without radiation. The lateral femoral cutaneous nerve provides sensory enervation to the anterolateral thigh and can be compressed as it passes under the inguinal ligament, especially in obese individuals, leading to a condition known as paresthetica meralgia.
Special Tests
- Leg-length testing: With the patient supine, take linear measurements from the ASIS to the medial malleolus on each extremity. Then, have the patient flex his or her knees, and observe if one knee is higher (longer tibia) or if it is more prominent (longer femur).
- Trendelenburg test: Have the patient stand on one foot; the examiner then observes for a pelvic tilt toward the side of the raised foot. This is an indication of weak abductors on the opposite hip.
- Thomas test: With the patient supine, the examiner places one hand under the patient's lumbar spine, and the patient flexes one hip toward the body. When the spine touches the examiner's hand, the pelvis is stabilized and further flexion now occurs solely from the hip. Flexion of the contralateral leg during further flexion of the ipsilateral hip or arching the back during extension may be a sign of a flexion contracture.
- Hop Test: Pain in the ipsilateral groin region when the patient hops on one leg may be a sign of a femoral neck stress fracture.
- FABER (flexion, abduction, external rotation) or Patrick test: This test is frequently used to differentiate lumbar spinal problems from primary hip pathology. This comprehensive maneuver elicits anterior hip or groin pain. If there is significant loss of ROM from a mechanical means (ie, not pain-inhibited), consider an intra-articular problem, such as hip arthritis or avascular necrosis. If groin pain is elicited and yet the range of motion is relatively normal, suspect iliopsoas tendinitis. If the FABER/Patrick test produces posterior hip pain, consider a disorder of the sacroiliac (SI) joint. To perform this test, the patient's affected hip is moved into flexion, abduction, and external rotation while he or she lies supine with one ankle placed over the opposite knee ("figure 4" position). If pain is elicited when the examiner presses down on the flexed knee, this test may indicate an SI joint pathology or adductor muscle and tendon pain.
- Ober test: With the patient lying on the unaffected side, passively abduct the upper leg and flex the knee to 90º. Slightly extend the hip, and observe if the hip drops into the adducted position. Decreased adduction is a sign of tightness in the tensor fasciae latae and/or the iliotibial band.
- The cause of many overuse injuries of the hip can be traced to biomechanical problems farther down the kinetic chain. One should exam the knees to determine valgus or varus alignment. The alignment of the hindfoot, pronation of the ankle, and cavus or planus foot type should be determined.
Causes
Rectus Femoris/Quadriceps
The rectus femoris originates at the ASIS (direct head) and AIIS (nondirect head) and crosses the hip and knee joint, making it the only quadriceps muscle to do so. It functions as a hip flexor and knee extender, and it receives innervation from the femoral nerve (L2-L4).
Strains of the rectus, which usually occur in the middle third of the thigh, may result in complete ruptures of the muscle belly, presenting as an acute enlargement of the affected thigh or a pseudotumorous growth. These deformities are out of proportion to their significance, however, because even complete ruptures of the rectus femoris result in little or no functional disability. The site of the strain is often tender to palpation and may be ecchymotic. An obvious defect can be palpated at times.
Chronic proximal rectus femoris or quadriceps pain can occur with apophysitis in the skeletally immature patient. Continued activity will weaken the growth plate, putting this area at risk for an avulsion after an acute stress of the muscle-tendon unit. This injury is accompanied by a pop or snap, with immediate pain and disability.
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Iliopsoas Bursitis/Tendinits6, 11, 12
The iliopsoas is the primary hip flexor, and it is also an external hip rotator. This muscle is a combination of the psoas major muscle (originating at the lateral surface of the T12-L4 vertebral bodies) and the iliacus muscle (iliac fossa origin) below the inguinal ligament which insert on the lesser trochanter of the femur. The iliopsoas muscle receives its innervations from the femoral nerve and lumbar plexus (L1-L3). The trochanteric bursa lies beneath the muscle and is the largest synovial bursa in humans. This bursa can be from 5-7 cm x 2-4 cm in size and can communicate directly with the hip joint. Pain from the bursa or tendon is usually caused by an overuse injury, acute trauma, or rheumatoid arthritis.
The mechanism of injury for an acute iliopsoas trauma is usually a sudden hyperextension, which is commonly seen in athletes who are involved in rowing, uphill running, track and field, and strength training. This type of injury is usually seen in young adults and is more common in women. Patients present with pain over the anterior thigh with a palpable and/or audible snap. A shortened stride on the affected side may be present, and this is usually due to guarding against hyperextension of the hip.
Chronic anterior hip pain may result from iliopsoas or rectus femoris tendinitis. An audible or palpable snap may be felt with flexion or extension of the hip. As in all tendinitis and tendinosis, this is a result of repetitious weight-bearing activities, such as running and jumping. These conditions will often occur after abrupt changes in levels of activity, such as during preseason training or when an individual is first training for a race. Because tendinosis is a degenerative process, less obvious changes in activity can lead to symptoms in older patients and will have a more insidious onset.
The symptoms of pain and tightness will initially start after an activity but will progress to occur during the workout over time. Eventually, the individuals will stop the workouts because of the pain, and their activities of daily living may be affected.
The patient will complain of anterior hip and groin pain that is worsened with extension of the hip or active flexion of the hip or active extension of the knee against resistance. Getting out of a car or walking up the steps will lead to increased pain.
A palpable mass may also be noted under the inguinal ligament, at which time a consideration of aspiration or a steroid injection may be considered if ultrasound guidance is available.
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Gluteus Medius Syndrome and Trochanteric Bursitis1, 8, 13, 14
The gluteus medius functions as a primary hip abductor. It originates at the external surface of the ilium and inserts onto the posterior lateral surface of the greater trochanter. This muscle is innervated by the superior gluteal nerve (L4-S1).
The greater trochanteric bursa lies directly lateral to the greater trochanter. This lateral growth of the femur abuts the tensor fasciae latae and lateral quadriceps muscles. The bursa provides lubrication and cushioning to allow the muscles to flex and extend over the trochanter without damaging the muscles. It also cushions the tendon before the attachment of the gluteus medius and minimus. Bursitis in this area can be secondary to changes in activity or training, biomechanical problems lower down the leg, or from direct trauma. These conditions lead to increased pressure of the muscles against the bursa and trochanter — with resultant inflammation.
Pain will occur with hip flexion such as walking, climbing stairs, or getting out of a car or a chair. Nocturnal pain while lying on the affected side is common. A snap is occasionally felt or heard in the lateral hip with flexion or extension.
Gluteus medius syndrome involves tenderness to palpation of the gluteus medius muscle, which can be triggered by sudden falls, prolonged weight bearing on one extremity for long periods, activity overuse, or sporting injuries. Most commonly, this situation is observed in middle-aged women who have embarked upon a vigorous walking program or who have started working out at a health club. Patients may present with pain that is transient and worsening over a time period, a Trendelenburg gait, and weakness. These symptoms specifically affect runners, as there is tilting of the pelvis with running. It is important for the clinician to examine the patient for a leg-length discrepancy.
Hip-abduction strengthening should be avoided in the initial stages of gluteus medius syndrome because it only provokes tendinitis. As the acute stage resolves, hip-abductor strengthening is important and is best achieved in the aquatic environment.
It can be difficult to distinguish between trochanteric bursitis and gluteus medius tendinitis due to their proximity at the insertion site. Resistance to abduction or internal rotation of the hip may help distinguish these 2 entities, as trochanteric bursitis will not elicit pain with resisted hip abduction, and gluteus medius tendinitis will present with more posterior tenderness to palpation at the insertion site. Diagnostic ultrasound can be performed to determine if fluid is present in the bursa or to look for echogenic changes that are consistent with tendinopathy. Ultrasound-guided injections into the greater trochanteric bursa will be more effective if fluid and distention of the bursa can be demonstrated.
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Groin/Adductor Strain
Adduction of the hip is performed by the gracilis, pectineus, obturator externus, adductor longus, adductor brevis, and adductor magnus muslces. The main origin is along the pubic ramus, and the insertions range from the trochanteric fossa to the tibial tuberosity. The obturator nerve (L2-L4) provides the main innervations for the adductor muscle group.
Adductor or groin strains are commonly seen in ice hockey and soccer players. These injuries are usually the result of strong eccentric contractions and rapid decelerations that occur during these sports activities, and they are often accompanied by a pop, with immediate resultant pain and disability. Often, weight bearing will be difficult, and the athlete may need to use crutches. The adductor longus is most commonly injured, and athletes classically present with pain with the following: (1) palpation of the muscle belly and insertion, (2) passive stretching, and (3) resistance to contraction.
Adductor strains are also common in football, figure skating, and track and field. Athletes at risk are those with decreased adductor strength, lack of off-season conditioning, inadequate warm-up and stretching, and a history of previous strains. Adductor strains are graded from first degree to third degree, ranging from a minimal loss of strength and ROM (first degree) to a complete loss of muscle function (third degree). If these injuries are not properly rehabilitated after the acute stage, they may become chronic, leading to a more frustrating situation for the athlete.
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Hamstring15, 16
The hamstrings function as hip extensors and consist of the semitendinosus muscle, semimembranosus muscle, and the biceps femoris. These muscles originate from the ischial tuberosity, with the short head of the biceps femoris coming off the middle third of the femur. They insert onto the medial tibia (semimembranosus and semitendinosus) and lateral fibula (biceps femoris).
Acute hamstring injuries occur with the acceleration associated with sprinting and court or field sports. A snap or pop is felt, and immediate pain will limit further participation. Risk factors for these injuries are similar to other acute injuries mentioned above, such as poor warm-ups, poor flexibility, or decreased strength from previous hamstring strains. Acute hamstring injuries most often occur within the mid belly of the muscle, but myotendinous rupture can occur.
Chronic hamstring pain can result from a poorly rehabilitated acute injury in which the strength was not completely restored. Proximal hamstring tendinitis is less common than chronic muscle-based pain. Apophysitis and acute avulsions from the ischial tuberosity occur in skeletally immature athletes, such as gymnasts and dancers.
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Further Reading
Keywords
trochanteric bursitis, gluteus medius tendonitis/tendinitis, rectus femoris tendonitis/tendinitis, adductor strain/tendonitis/tendinitis, quadriceps tendonitis/tendinitis, hamstring tendonitis/tendinitis, groin injury, groin pull, sports hernia, iliopsoas tendonitis/tendinitis/bursitis, apophysitis, avulsion fracture, tendinopathy
