CHAPTER OUTLINE
History 3
Physical Examination 4
General Tests 5
Leg Length Measurement 5
Thomas Test 5
Trendelenburg Test 5
Patrick Test (FABER [ F lexion, AB duction, E xternal R otation]) 5
Resisted Straight Leg Raise 5
Ober Test 5
Specific Diagnoses 5
Stress Fractures 5
Snapping Hip 6
Acetabular Labral Tears 6
Femoroacetabular Impingement 6
Osteonecrosis 6
Osteitis Pubis (Pubic Symphysitis) 7
Bursitis 7
Bone Marrow Edema Syndrome (Transient Osteoporosis of the Hip) 7
Nerve Entrapment Syndromes 7
Athletic Pubalgia 7
Inflammatory Arthritis 7
Osteoarthritis 7
Other Causes of Hip Pain 8
So-called hip pain in an adult can originate from the hip joint, may be referred from another location (i.e., pelvis, lumbar spine, or sacroiliac joints), or may be the result of a systemic process. Evaluation of this pain requires a careful and thorough history and physical examination. The evaluation should include orthopedic and nonorthopedic components because many nonorthopedic conditions may manifest as hip pain. Evaluation of a patient with hip pain requires an understanding of musculoskeletal disorders related to the hip and a vast array of nonorthopedic diagnoses distant from the hip region.
As with all organ systems, evaluation begins with a thorough history and physical examination. Most of the time, the etiology of pain may be determined by using the history and physical examination, and then may be confirmed by imaging studies such as plain radiography, MRI, and CT. Common diagnoses causing hip pain include stress fractures, avascular necrosis, snapping hip disorders, labral tears, bursitis, synovitis, fractures, muscle strains, osteitis pubis, compression neuropathies, femoral acetabular impingement, dysplasia, osteoporosis, and arthritis (osteoarthritis and inflammatory arthritis). Although beyond the scope of this chapter, acute hip pathologies such as infection, contusions, fractures, and dislocations, must always be considered if suggested by the history and physical examination. A simple mnemonic that can be helpful for assessment of the painful hip is CTV MIND :
C—Congenital (dysplasia)
T—Traumatic (stress fracture, fracture)
V—Vascular (avascular necrosis)
M—Metabolic (osteoporosis)
I—Inflammatory, Infection, Impingement
N—Neoplasia
D—Degenerative, Drugs
HISTORY
The location, frequency, chronicity, and modifying pain factors all are important to consider when evaluating a patient with hip discomfort. Many patients lump all pain in the lower extremity into their description of “hip pain.” It is important to elicit a clear location of pain. Patients report that they have “hip pain,” but with careful questioning this pain is discovered to be in the posterior buttocks, lateral thigh, groin, anterior thigh, or low back. Pain in the buttocks or lateral thigh may be related to pathology in the lumbar spine or sometimes the thigh musculature.
Radiation of the pain can help determine its etiology. Pain originating in the posterior buttocks and radiating down the lateral thigh and leg into the foot is often spine related. Groin or thigh pain with radiation to the knee is often the result of pathology of the joint capsule or synovial lining.
The timing of onset and duration of the pain are important in differentiating the various pathologies. Acute sudden onset of pain is usually related to trauma or sports injuries. Traumatic etiologies such as acute fractures and dislocations are readily diagnosed and should be addressed immediately. Patients with nontraumatic acute injuries may experience disability only in their hobby or activity of interest. Labral tears may occur after a sudden twisting motion during routine sports activity and cause significant disability. The patient may be asymptomatic at rest but unable to participate in his or her activity. More chronic symptoms also may characterize a labral tear and can develop over years and be accompanied by limited range of motion and declining function.
Many other questions should be asked about the pain characteristics. Is the condition improving, worsening, or staying the same? Does this pain awaken the patient at night? What (e.g., position, medication) makes the symptoms better? What makes the symptoms worse? Are there any activities or positions unique to the patient that exacerbate the symptoms?
A past medical history should be obtained from all patients. It is important to determine if the patient has a history of hip disease during childhood (e.g., developmental dysplasia of the hip, slipped capital femoral epiphysis, Legg-Calvé-Perthes disease) or has had previous surgery on the hip. Systemic diseases that may be related to hip disease include coagulopathies, collagen vascular diseases, and malignancies. A history of asthma or skin disorder that has been treated with oral or intravenous steroids may suggest avascular necrosis as the cause of the pain. A social history also is important; avascular necrosis should be suspected in patients with a history of alcoholism.
The patient should be asked about social and recreational interests. Soccer, rugby, and marathon running all have been shown to be associated with an increased incidence of degenerative arthritis of the hip. Runners who have drastically increased their mileage and military recruits have a high propensity for stress fractures around the hip. A family history also should be evaluated; osteoarthritis of the hip and hand are associated with a high genetic influence.
A thorough review of systems is important in the patient with hip pain. The differential diagnosis of hip and groin pain includes many nonmusculoskeletal disorders. If the source of the groin pain is obviously not the hip, and the review of systems reveals another potential source of the pathology, appropriate referrals to primary care physicians, surgeons, urologists, and gynecologists may be appropriate. Questions that are related to the patient’s general health and that probe topics such as weight loss, fevers, chills, and malaise should be asked. Unexplained weight loss may indicate a malignancy, and fevers and chills may guide the examiner toward a diagnosis of infection.
Disorders of the abdominal wall, such as inguinal hernias or rectus abdominis strains, may cause hip pain. Patients should be questioned to determine whether they have any bulges or palpable masses in the groin that might represent a hernia. Hernias are often more pronounced with coughing or other Valsalva maneuvers.
It is important to perform a through review of the gastrointestinal and genitourinary systems because hip and groin pain may originate from abdominal or pelvic pathology. Nausea, vomiting, constipation, diarrhea, and gastrointestinal bleeding can indicate a gastrointestinal cause of pain such as inflammatory bowel disease, diverticulosis, diverticulitis, abdominal aortic aneurysm, or appendicitis. Urinary symptoms such as frequency, polyuria, nocturia, or hematuria may suggest a urinary tract infection or nephrolithiasis.
The male and female reproductive systems should be addressed to rule out pathology that might be causing the pain. Prostatitis, epididymitis, hydroceles, varicoceles, testicular torsions, and testicular neoplasms all have been known to cause groin pain in men. Women of childbearing age should be asked about their menstrual history to determine if an ectopic pregnancy, dysmenorrhea, or endometriosis is a cause of their pain. Women also should be asked if they have had any signs or a history of sexually transmitted diseases that may have resulted in pelvic inflammatory disease. Very active women with eating disorders, amenorrhea, and osteoporosis (the so-called female athlete triad) have a very high rate of stress fractures. Finally, musculoskeletal causes not related to the hip, such as back pain, history of herniated disks, and sacroiliac injuries, must be considered.
PHYSICAL EXAMINATION
The physical examination begins long before the examiner’s hands are placed on the patient. When the patient first walks into the examination room or the waiting area, the examiner should evaluate the patient’s gait and stance. Does the patient have an antalgic gait? What is the patient’s standing posture? Does the patient walk with ambulatory aids? The patient should be specifically asked to walk for the examiner. On the affected side, the patient may have a shortened stance phase or stride length to limit the amount of time weight is loaded on the affected extremity. If the patient has weak abductors, he or she may walk with a Trendelenburg lurch. With this type of gait, the patient compensates for abductor weakness by leaning over the painful hip in an attempt to shift the center of gravity to the affected side. With the patient undressed, the examiner should evaluate for skin lesions, obvious deformities, or surgical scars.
A complete set of vital signs including temperature is important to attain if infection is suspected. An elevated temperature may clue the examiner into the diagnosis of septic arthritis or non–hip-related sepsis, such as prostatitis, urinary tract infection, pelvic inflammatory disease, or psoas abscess. A thorough examination of areas distant to the hip should be done for non–hip-related causes of pain. The lumbar spine, sacroiliac joints, abdomen, inguinal region and groin (for femoral and inguinal hernias), and knee should be evaluated. A femoral pulse should be taken to rule out femoral aneurysms or pseudoaneurysms, which can manifest as a palpable pulsatile masses. Active and passive range of motion of the affected hip and unaffected side should be performed for comparison. The strength of the major muscle groups of the hip in flexion, extension, abduction, adduction, external rotation, and internal rotation should be tested. Muscle testing is performed on the classic scale of 0 to 5. A score of 5 indicates full strength against gravity and resistance; 4, full range of motion against some resistance; 3, motion against gravity with no resistance; 2, motion with gravity eliminated; 1, evidence only of muscle contractility; and 0, no sign of muscle contraction. Sensation should be evaluated paying close attention to the dermatomal distribution of the lumbar spine. L1 usually innervates the suprapubic area and groin; L2, the anterior thigh; L3, the lower anterior thigh and knee; L4, the medial calf; and L5, the lateral calf. Distal sensation must always be evaluated to rule out nerve injuries, which may result in hip or groin pain. Finally, peripheral pulses must be checked.
GENERAL TESTS
Leg Length Measurement
Leg lengths should be measured to determine if there is a difference from side to side. It is important to distinguish a true versus apparent leg length deficiency. With apparent or functional leg length discrepancy, the deficiency may be due to a pelvic obliquity, contractures, or scoliosis. To measure the true leg length inequality, the patient is placed supine on the examination table making sure the pelvis is level (anterior superior iliac spine [ASIS] in a straight line and lower extremities perpendicular to that). The legs should be symmetrically positioned so that they are approximately 10 to 20 cm apart and parallel to each other. Measurement may be made from the ASIS to the medial malleolus on each side. Most patients usually tolerate a leg length inequality of 1 to 2 cm. If a leg length inequality is found, the location of the deficiency may be determined by measuring from the ASIS to the greater trochanter, the greater trochanter to the knee joint, and the knee joint to the medial malleolus, and comparing these measurements with the contralateral side to determine the location of the discrepancy.
Apparent leg length inequalities are evaluated by measuring from a fixed point in the center of the body, such as the umbilicus or xiphoid process. Alternatively, apparent leg length inequalities may be measured by having the patient stand on graduated blocks until the leg lengths feel equal.
Thomas Test
The Thomas test is used to evaluate if there is a hip flexion contracture. The unaffected leg is flexed to stabilize the pelvis and eliminate lumbar lordosis. While lying supine on the examination table, the patient flexes the contralateral hip bringing the knee to the chest; this flattens out the lumbar spine. If the leg being evaluated remains on the table, there is no flexion contracture present. If the straight leg comes off the table as the patient flexes the contralateral limb, a flexion contracture is present. This flexion contracture may be quantitated by measuring the angle the straight leg makes with the table.
Trendelenburg Test
The Trendelenburg test assesses the strength of the hip abductors and their ability to stabilize the pelvis. The patient is instructed to stand on the affected leg with the other leg flexed forward. A normal or negative test results in the pelvis on the contralateral side rising. A positive test is one in which the pelvis on the contralateral side drops because the abductors are unable to stabilize the pelvis.
Patrick Test (FABER [ F lexion, AB duction, E xternal R otation])
The Patrick test is used to differentiate hip from sacroiliac pathology. The affected foot is placed on the contralateral knee so that the hip being tested is in a position of flexion abduction and external rotation, which is sometimes called a figure-of-4 position. This position is exaggerated further during testing by pushing the knee toward the floor; if the pain is posterior, sacroiliac pathology may be present. If the pain is in the groin, pathology is more likely related to the hip joint.
Resisted Straight Leg Raise
The resisted straight leg raise test or Stinchfield test is used to reproduce intra-articular pathology. From the supine position, their patient is asked to flex the hip with the knee extended (i.e., straight leg raise). The examiner places resistance on the lower leg. Groin pain or weakness with this test may reproduce intra-articular pathology and denotes a positive test.
Ober Test
The Ober test is used to evaluate contracture or tightness of the iliotibial band (ITB) and fascia lata. The patient is placed on their side with the affected side up. The lower leg is flexed at the hip and knee. The affected (upper) hip is extended, and the knee is flexed to 90 degrees. Hip extension causes the iliotibial tract to lie over the greater trochanter. The examiner assists the patient in abducting the extremity. The examiner then releases the extremity from the abducted position. The test is negative if the extremity falls back to the examination table. If the extremity remains abducted, the test is positive.