Evaluation of the Patient with Hip Pain

JOHN J. WILSON; MASARU FURUKAWA

JOHN J. WILSON, MD, MS, AND MASARU FURUKAWA, MD, MS

Am Fam Physician. 2014;89(1):27-34

A more recent article on hip pain in adults is available.

Patient information: See related handout on hip pain, written by the authors of this article.

Author disclosure: No relevant financial affiliations.

Hip pain is a common and disabling condition that affects patients of all ages. The differential diagnosis of hip pain is broad, presenting a diagnostic challenge. Patients often express that their hip pain is localized to one of three anatomic regions: the anterior hip and groin, the posterior hip and buttock, or the lateral hip. Anterior hip and groin pain is commonly associated with intra-articular pathology, such as osteoarthritis and hip labral tears. Posterior hip pain is associated with piriformis syndrome, sacroiliac joint dysfunction, lumbar radiculopathy, and less commonly ischiofemoral impingement and vascular claudication. Lateral hip pain occurs with greater trochanteric pain syndrome. Clinical examination tests, although helpful, are not highly sensitive or specific for most diagnoses; however, a rational approach to the hip examination can be used. Radiography should be performed if acute fracture, dislocations, or stress fractures are suspected. Initial plain radiography of the hip should include an anteroposterior view of the pelvis and frog-leg lateral view of the symptomatic hip. Magnetic resonance imaging should be performed if the history and plain radiograph results are not diagnostic. Magnetic resonance imaging is valuable for the detection of occult traumatic fractures, stress fractures, and osteonecrosis of the femoral head. Magnetic resonance arthrography is the diagnostic test of choice for labral tears.

Hip pain is a common presentation in primary care and can affect patients of all ages. In one study, 14.3% of adults 60 years and older reported significant hip pain on most days over the previous six weeks.¹ Hip pain often presents a diagnostic and therapeutic challenge. The differential diagnosis of hip pain (eTable A) is broad, including both intra-articular and extra-articular pathology, and varies by age. A history and physical examination are essential to accurately diagnose the cause of hip pain.

Clinical recommendation	Evidence rating	References
Initial plain radiography of the hip should include an anteroposterior view of the pelvis and a frog-leg lateral view of the symptomatic hip.	C	⁴
Magnetic resonance imaging should be used for detection of occult hip fractures, stress fractures, and osteonecrosis of the femoral head.	C	²³, ³⁰, ³³
Magnetic resonance arthrography is the diagnostic test of choice for labral tears.	C	⁶, ¹⁹
Ultrasonography is a helpful diagnostic modality for patients with suspected bursitis, joint effusion, or functional causes of hip pain (e.g., snapping hip), and can be employed for therapeutic imaging-guided injections and aspirations around the hip.	C	⁸, ⁹

Diagnosis	Pain characteristics	History/risk factors	Examination findings	Additional testing
Anterior thigh pain
Meralgia paresthetica	Paresthesia, hypesthesia	Obesity, pregnancy, tight pants or belt, conditions with increased intra-abdominal pressure	Anterior thigh hypesthesia, dysesthesia	None
Anterior groin pain
Athletic pubalgia (sports hernia)	Dull, diffuse pain radiating to inner thigh; pain with direct pressure, sneezing, sit-ups, kicking, Valsalva maneuver	Soccer, rugby, football, hockey players	No hernia, tenderness of the inguinal canal or pubic tubercle, adductor origin, pain with resisted sit-up or hip flexion	Radiography: No bony involvement
Athletic pubalgia (sports hernia)		Soccer, rugby, football, hockey players		MRI: Can show tear or detachment of the rectus abdominis or adductor longus
Anterolateral hip and groin pain (C sign)
Femoral neck fracture/stress fracture	Deep, referred pain; pain with weight bearing	Females (especially with female athlete triad), endurance athletes, low aerobic fitness, steroid use, smokers	Painful ROM, pain on palpation of greater trochanter	Radiography: Cortical disruption
Femoral neck fracture/stress fracture	Deep, referred pain; pain with weight bearing		Painful ROM, pain on palpation of greater trochanter	MRI: Early bony edema
Femoroacetabular impingement	Deep, referred pain; pain with standing after prolonged sitting	Pain with getting in and out of a car	FADIR and FABER tests are sensitive	Radiography: Cam or pincer deformity, acetabular retroversion, coxa profunda
Hip labral tear	Dull or sharp, referred pain; pain with weight bearing	Mechanical symptoms, such as catching or painful clicking; history of hip dislocation	Trendelenburg or antalgic gait, loss of internal rotation, positive FADIR and FABER tests	MRI: Can show a labral tear
Hip labral tear	Dull or sharp, referred pain; pain with weight bearing			Magnetic resonance arthrography: offers added sensitivity and specificity
Iliopsoas bursitis (internal snapping hip)	Deep, referred pain; intermittent catching, snapping, or popping	Ballet dancers, runners	Snap with FABER to extension, adduction, and internal rotation; reproduction of snapping with extension of hip from flexed position	Radiography: No bony involvement
				MRI: Bursitis and edema of the iliotibial band
				Ultrasonography: Tendinopathy, bursitis, fluid around tendon
				Dynamic ultrasonography: Snapping of iliopsoas or iliotibial band over greater trochanter
Legg-Calvé-Perthes disease	Deep, referred pain; pain with weight bearing	2 to 12 years of age, male predominance	Antalgic gait, limited ROM or stiffness	Radiography: Early small femoral epiphysis, sclerosis and flattening of the femoral head
Loose bodies and chondral lesions	Deep, referred pain; painful clicking	Mechanical symptoms, history of hip dislocation or low-energy trauma, history of Legg-Calvé-Perthes disease	Limited ROM, catching and grinding with provocative maneuvers, positive FADIR and FABER tests	Radiography: Can show ossified or osteochondral loose bodies
Loose bodies and chondral lesions	Deep, referred pain; painful clicking			MRI: Can detect chondral and fibrous loose bodies
Osteoarthritis of the hip	Deep, aching pain and stiffness; pain with weight bearing	Older than 50 years, pain with activity that is relieved with rest	Internal rotation < 15 degrees, flexion < 115 degrees	Radiography: Presence of osteophytes at the acetabular joint margin, asymmetrical joint-space narrowing, subchondral sclerosis and cyst formation
Osteonecrosis of the hip	Deep, referred pain; pain with weight bearing	Adults: Lupus, sickle cell disease, human immunodeficiency virus infection, corticosteroid use, smoking, and alcohol use; insidious onset, but can be acute with history of trauma	Pain on ambulation, positive log roll test, gradual limitation of ROM	Radiography: Femoral head lucency and subchondral sclerosis, subchondral collapse (i.e., crescent sign), flattening of the femoral head
Osteonecrosis of the hip	Deep, referred pain; pain with weight bearing			MRI: Bony edema, subchondral collapse
Slipped capital femoral epiphysis	Deep, referred pain; pain with weight bearing	11 to 14 years of age, overweight (80th to 100th percentile)	Antalgic gait with foot externally rotated on occasion, positive log roll and straight leg raise against resistance tests, pain with hip internal rotation relieved with external rotation	Radiography: Widened epiphysis early, slippage of femur under epiphysis later
Septic arthritis	Refusal to bear weight, pain with leg movement	Children: 3 to 8 years of age, fever, ill appearance Adults: Older than 80 years, diabetes mellitus, rheumatoid arthritis, recent joint surgery, hip or knee prostheses	Guarding against any ROM; pain with passive ROM	Hip aspiration guided by fluoroscopy, computed tomography, or ultrasonography; Gram stain and culture of joint aspirate
Septic arthritis	Refusal to bear weight, pain with leg movement		Guarding against any ROM; pain with passive ROM	MRI: Useful for differentiating septic arthritis from transient synovitis
Transient synovitis	Refusal to bear weight	Children: 3 to 8 years of age, sometimes fever and ill appearance	Pain with extremes of ROM
Lateral pain
External snapping hip*	Pain with direct pressure, radiation down lateral thigh, snapping or popping	All age groups, audible snap with ambulation	Positive Ober test, snap with Ober test, pain over greater trochanter	Radiography: No bony involvement
				MRI: Bursitis and edema of the iliotibial band
				Ultrasonography: Tendinopathy, bursitis, fluid around tendon
Greater trochanteric bursitis*	Pain with direct pressure, radiation down lateral thigh	Runners, middle-aged women	Pain over greater trochanter	Dynamic ultrasonography: Snapping of iliopsoas or iliotibial band over greater trochanter
Greater trochanteric pain syndrome	Pain with direct pressure, radiation down lateral thigh	Associated with knee osteoarthritis, increased body mass index, low back pain; female predominance	Proximal iliotibial band tenderness, Trendelenburg gait is sensitive and specific
Posterolateral pain
Gluteal muscle tear or avulsion*	Pain with direct pressure, radiation down lateral thigh and buttock	Middle-aged women	Weak hip abduction, pain with resisted external rotation, Trendelenburg gait is sensitive and specific	MRI: Gluteal muscle edema or tears
Iliac crest apophysis avulsion	Tenderness to direct palpation	History of direct trauma, skeletal immaturity (younger than 25 years)	Iliac crest tenderness and/or ecchymosis	Radiography: Apophysis widening, soft tissue swelling around iliac crest
Posterior pain
Hamstring muscle strain or avulsion	Buttock pain, pain with direct pressure	Eccentric muscle contraction while hip flexed and leg extended Skeletal immaturity, eccentric muscle contraction (cutting, kicking, jumping)	Ischial tuberosity tenderness, ecchymosis, weakness to leg flexion, palpable gap in hamstring	Radiography: Avulsion or strain of hamstring attachment to ischium
Ischial apophysis avulsion	Buttock pain, pain with direct pressure			MRI: Hamstring edema and retraction
Ischiofemoral impingement	Buttock or back pain with posterior thigh radiation, sciatica symptoms	Groin and/or buttock pain that may radiate distally	None established	MRI: Soft tissue edema around quadratus femoris muscle
Piriformis syndrome	Buttock pain with posterior thigh radiation, sciatica symptoms	History of direct trauma to buttock or pain with sitting, weakness and numbness are rare compared with lumbar radicular symptoms	Positive log roll test, tenderness over the sciatic notch	MRI: Lumbar spine has no disk herniation, piriformis muscle atrophy or hypertrophy, edema surrounding the sciatic nerve
Sacroiliac joint dysfunction	Pain radiates to lumbar back, buttock, and groin	Female predominance, common in pregnancy, history of minor trauma	FABER test elicits posterior pain localized to the sacroiliac joint, sacroiliac joint line tenderness	Radiography: Possibly no findings, narrowing and sclerotic changes of the sacroiliac joint space

Anatomy

The hip joint is a ball-and-socket synovial joint designed to allow multiaxial motion while transferring loads between the upper and lower body. The acetabular rim is lined by fibrocartilage (labrum), which adds depth and stability to the femoroacetabular joint. The articular surfaces are covered by hyaline cartilage that dissipates shear and compressive forces during load bearing and hip motion. The hip's major innervating nerves originate in the lumbosacral region, which can make it difficult to distinguish between primary hip pain and radicular lumbar pain.

The hip joint's wide range of motion is second only to that of the glenohumeral joint and is enabled by the large number of muscle groups that surround the hip. The flexor muscles include the iliopsoas, rectus femoris, pectineus, and sartorius muscles. The gluteus maximus and hamstring muscle groups allow for hip extension. Smaller muscles, such as gluteus medius and minimus, piriformis, obturator externus and internus, and quadratus femoris muscles, insert around the greater trochanter, allowing for abduction, adduction, and internal and external rotation.

In persons who are skeletally immature, there are several growth centers of the pelvis and femur where injuries can occur. Potential sites of apophyseal injury in the hip region include the ischium, anterior superior iliac spine, anterior inferior iliac spine, iliac crest, lesser trochanter, and greater trochanter. The apophysis of the superior iliac spine matures last and is susceptible to injury up to 25 years of age.²

Evaluation of Hip Pain

HISTORY

Age alone can narrow the differential diagnosis of hip pain. In prepubescent and adolescent patients, congenital malformations of the femoroacetabular joint, avulsion fractures, and apophyseal or epiphyseal injuries should be considered. In those who are skeletally mature, hip pain is often a result of musculotendinous strain, ligamentous sprain, contusion, or bursitis. In older adults, degenerative osteoarthritis and fractures should be considered first.

Patients with hip pain should be asked about antecedent trauma or inciting activity, factors that increase or decrease the pain, mechanism of injury, and time of onset. Questions related to hip function, such as the ease of getting in and out of a car, putting on shoes, running, walking, and going up and down stairs, can be helpful.³ Location of the pain is informative because hip pain often localizes to one of three basic anatomic regions: the anterior hip and groin, posterior hip and buttock, and lateral hip (eFigure A).

PHYSICAL EXAMINATION

The hip examination should evaluate the hip, back, abdomen, and vascular and neurologic systems. It should start with a gait analysis and stance assessment (Figure 1), followed by evaluation of the patient in seated, supine, lateral, and prone positions (Figures 2 through 6, and eFigure B). Physical examination tests for the evaluation of hip pain are summarized in Table 1.

Test	Other names	Positioning	Positive findings	Differential diagnosis
Gait testing (C sign, Figure 1A; gait analysis, Figure 1B)	—	Standing	Antalgic gait, Trendelenburg gait, pelvic wink (rotation of more than 40 degrees in the axial plane toward the affected hip when terminally extending the hip), excessive pronation or supination of the ankles, and limps caused by differing leg lengths	Hip labral tear, transient synovitis, Legg-Calvé-Perthes disease, SCFE
Modified Trendelenburg test (Figure 1C)	Single leg stance phase	Standing	2-cm drop in the level of the iliac crest, indicating weakness on the contralateral side	Hip labral tear, transient synovitis, Legg-Calvé-Perthes disease, SCFE
ROM testing (Figure 2)	—	Supine, lateral, or sitting	Pain with passive ROM, limited ROM	Pain with passive ROM: Transient synovitis, septic arthritis
ROM testing (Figure 2)	—	Supine, lateral, or sitting	Pain with passive ROM, limited ROM	Limited ROM: Loose bodies, chondral lesions, osteoarthritis, Legg-Calvé-Perthes disease, osteonecrosis
FABER test (Figure 3)	Patrick test	Supine	Posterior pain localized to the sacroiliac joint, lumbar spine, or posterior hip; groin pain with the test is sensitive for intra-articular pathology	Hip labral tear, loose bodies, chondral lesions, femoral acetabular impingement, osteoarthritis, sacroiliac joint dysfunction, iliopsoas bursitis
FADIR test (Figure 4)	Impingement test	Supine	Pain	Hip labral tear, loose bodies, chondral lesions, femoral acetabular impingement
Log roll test (Figure 5)	Passive supine rotation, Freiberg test	Supine	Restricted movement, pain	Piriformis syndrome, SCFE
Straight leg raise against resistance test (Figure 6)	Stinchfield test	Supine	Weakness to resistance, pain	Athletic pubalgia (sports hernia), SCFE, femoral acetabular impingement
Ober test (eFigure B)	Passive adduction	Lateral	Passive adduction past midline cannot be achieved	External snapping hip, greater trochanteric pain syndrome

IMAGING

Radiography. Radiography of the hip should be performed if there is any suspicion of acute fracture, dislocation, or stress fracture. Initial plain radiography of the hip should include an anteroposterior view of the pelvis and a frog-leg lateral view of the symptomatic hip.⁴

Magnetic Resonance Imaging and Arthrography. Conventional magnetic resonance imaging (MRI) of the hip can detect many soft tissue abnormalities, and is the preferred imaging modality if plain radiography does not identify specific pathology in a patient with persistent pain.⁵ Conventional MRI has a sensitivity of 30% and an accuracy of 36% for diagnosing hip labral tears, whereas magnetic resonance arthrography provides added sensitivity of 90% and accuracy of 91% for the detection of labral tears.^6,7

Ultrasonography. Ultrasonography is a useful technique for evaluating individual tendons, confirming suspected bursitis, and identifying joint effusions and functional causes of hip pain.⁸ Ultrasonography is especially useful for safely and accurately performing imaging-guided injections and aspirations around the hip.⁹ It is ideal for an experienced ultrasonographer to perform the diagnostic study; however, emerging evidence suggests that less experienced clinicians with appropriate training can make diagnoses with reliability similar to that of an experienced musculoskeletal ultrasonographer.^10,11

Differential Diagnosis of Anterior Hip Pain

Anterior hip or groin pain suggests involvement of the hip joint itself. Patients often localize pain by cupping the anterolateral hip with the thumb and forefinger in the shape of a “C.” This is known as the C sign (Figure 1A).

OSTEOARTHRITIS

Osteoarthritis is the most likely diagnosis in older adults with limited motion and gradual onset of symptoms. Patients have a constant, deep, aching pain and stiffness that are worse with prolonged standing and weight bearing. Examination reveals decreased range of motion, and extremes of hip motion often cause pain. Plain radiographs demonstrate the presence of asymmetrical joint-space narrowing, osteophytosis, and subchondral sclerosis and cyst formation.¹²

FEMOROACETABULAR IMPINGEMENT

Patients with femoroacetabular impingement are often young and physically active. They describe insidious onset of pain that is worse with sitting, rising from a seat, getting in or out of a car, or leaning forward.¹³ The pain is located primarily in the groin with occasional radiation to the lateral hip and anterior thigh.¹⁴ The FABER test (flexion, abduction, external rotation; Figure 3) has a sensitivity of 96% to 99%. The FADIR test (flexion, adduction, internal rotation; Figure 4), log roll test (Figure 5), and straight leg raise against resistance test (Figure 6) are also effective, with sensitivities of 88%, 56%, and 30%, respectively.^14,15 In addition to the anteroposterior and lateral radiograph views, a Dunn view should be obtained to help detect subtle lesions.¹⁶

HIP LABRAL TEAR

Hip labral tears cause dull or sharp groin pain, and one-half of patients with a labral tear have pain that radiates to the lateral hip, anterior thigh, and buttock. The pain usually has an insidious onset, but occasionally begins acutely after a traumatic event. About one-half of patients with this injury also have mechanical symptoms, such as catching or painful clicking with activity.¹⁷ The FADIR and FABER tests are effective for detecting intra-articular pathology (the sensitivity is 96% to 75% for the FADIR test and is 88% for the FABER test), although neither test has high specificity.^14,15,18 Magnetic resonance arthrography is considered the diagnostic test of choice for labral tears.^6,19 However, if a labral tear is not suspected, other less invasive imaging modalities, such as plain radiography and conventional MRI, should be used first to rule out other causes of hip and groin pain.

ILIOPSOAS BURSITIS (INTERNAL SNAPPING HIP)

Patients with this condition have anterior hip pain when extending the hip from a flexed position, often associated with intermittent catching, snapping, or popping of the hip.²⁰ Dynamic real-time ultrasonography is particularly useful in evaluating the various forms of snapping hip.⁸

OCCULT OR STRESS FRACTURE

Occult or stress fracture of the hip should be considered if trauma or repetitive weight-bearing exercise is involved, even if plain radiograph results are negative.²¹ Clinically, these injuries cause anterior hip or groin pain that is worse with activity.²¹ Pain may be present with extremes of motion, active straight leg raise, the log roll test, or hopping.²² MRI is useful for the detection of occult traumatic fractures and stress fractures not seen on plain radiographs.²³

TRANSIENT SYNOVITIS AND SEPTIC ARTHRITIS

Acute onset of atraumatic anterior hip pain that results in impaired weight bearing should raise suspicion for transient synovitis and septic arthritis. Risk factors for septic arthritis in adults include age older than 80 years, diabetes mellitus, rheumatoid arthritis, recent joint surgery, and hip or knee prostheses.²⁴ Fever, complete blood count, erythrocyte sedimentation rate, and C-reactive protein level should be used to evaluate the risk of septic arthritis.^25,26 MRI is useful for differentiating septic arthritis from transient synovitis.^27,28 However, hip aspiration using guided imaging such as fluoroscopy, computed tomography, or ultrasonography is recommended if a septic joint is suspected.²⁹

OSTEONECROSIS

Legg-Calvé-Perthes disease is an idiopathic osteonecrosis of the femoral head in children two to 12 years of age, with a male-to-female ratio of 4:1.⁴ In adults, risk factors for osteonecrosis include systemic lupus erythematosus, sickle cell disease, human immunodeficiency virus infection, smoking, alcoholism, and corticosteroid use.^30,31 Pain is the presenting symptom and is usually insidious. Range of motion is initially preserved but can become limited and painful as the disease progresses.³² MRI is valuable in the diagnosis and prognostication of osteonecrosis of the femoral head.^30,33

Differential Diagnosis of Posterior Hip and Buttock Pain

PIRIFORMIS SYNDROME AND ISCHIOFEMORAL IMPINGEMENT

Piriformis syndrome causes buttock pain that is aggravated by sitting or walking, with or without ipsilateral radiation down the posterior thigh from sciatic nerve compression.^34,35 Pain with the log roll test is the most sensitive test, but tenderness with palpation of the sciatic notch can help with the diagnosis.³⁵

Ischiofemoral impingement is a less well-understood condition that can lead to nonspecific buttock pain with radiation to the posterior thigh.^36,37 This condition is thought to be a result of impingement of the quadratus femoris muscle between the lesser trochanter and the ischium.

Unlike sciatica from disc herniation, piriformis syndrome and ischiofemoral impingement are exacerbated by active external hip rotation. MRI is useful for diagnosing these conditions.³⁸

OTHER

Other causes of posterior hip pain include sacroiliac joint dysfunction,³⁹ lumbar radiculopathy,⁴⁰ and vascular claudication.⁴¹ The presence of a limp, groin pain, and limited internal rotation of the hip is more predictive of hip disorders than disorders originating from the low back.⁴²

Differential Diagnosis of Lateral Hip Pain

GREATER TROCHANTERIC PAIN SYNDROME

Lateral hip pain affects 10% to 25% of the general population.⁴³ Greater trochanteric pain syndrome refers to pain over the greater trochanter. Several disorders of the lateral hip can lead to this type of pain, including iliotibial band thickening, bursitis, and tears of the gluteus medius and minimus muscle attachment.^43–45 Patients may have mild morning stiffness and may be unable to sleep on the affected side. Gluteus minimus and medius injuries present with pain in the posterior lateral aspect of the hip as a result of partial or full-thickness tearing at the gluteal insertion. Most patients have an atraumatic, insidious onset of symptoms from repetitive use.^43,45,46

Data Sources: We searched articles on hip pathology in American Family Physician, along with their references. We also searched the Agency for Healthcare Research and Quality Evidence Reports, Clinical Evidence, Institute for Clinical Systems Improvement, the U.S. Preventive Services Task Force guidelines, the National Guideline Clearinghouse, and UpToDate. We performed a PubMed search using the keywords greater trochanteric pain syndrome, hip pain physical examination, imaging femoral hip stress fractures, imaging hip labral tear, imaging osteomyelitis, ischiofemoral impingement syndrome, meralgia paresthetica review, MRI arthrogram hip labrum, septic arthritis systematic review, and ultrasound hip pain. Search dates: March and April 2011, and August 15, 2013.

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