CAUSAS DE DOR COXOFEMURAL

Hip pain is a common symptom with a number of possible causes . In a survey of 6596 adults ages 60 years and older, 14.3 percent reported significant hip pain on most days over the past six weeks .Trochanteric and gluteus medius bursitis, osteoarthritis, and fractures of the femur are the most common conditions affecting the hip. The character and location of the pain, the movement and positions that reproduce the pain, and the affect on ambulation can be used to distinguish the conditions affecting soft tissues from disorders affecting the hip joint and adjacent bones.
Pain is the most common complaint in patients with hip problems. In most cases, a careful history and physical examination can determine the etiology.
PAIN PATTERNS — The character and location of pain is the key element in the differential diagnosis of hip pain. Increased pain with or after use (particularly with weight-bearing) and improvement with rest is the hallmark of a structural joint problem, particularly osteoarthritis. By comparison, constant pain, especially pain at night, suggests an infectious, inflammatory, or neoplastic process.
LATERAL HIP PAIN AGGRAVATED BY DIRECT PRESSURE — Lateral hip pain is unlikely to be due to hip joint disease. Lateral hip pain that is aggravated by direct pressure is the classic pattern of trochanteric bursitis. Depending upon the degree of inflammation and swelling, pressure sensitivity ranges from mild morning pain and stiffness to intolerance to sleeping on the affected side.
Progressive lateral hip pain that is aggravated by direct pressure and weight bearing can also be seen with direct involvement of the femur (eg, with metastatic cancer). Thus, patients who otherwise may be at risk for malignancy (eg, older individuals with weight loss, history of cancer) may need radiographic testing to rule out bone involvement.
LATERAL HIP PAIN ASSOCIATED WITH PARESTHESIAS AND HYPESTHESIAS — Lateral hip pain accompanied by paresthesias or hypesthesias is the classic presentation of meralgia paresthetica (lateral femoral cutaneous nerve entrapment). Meralgia paresthetica is characterized by a localized area of pain (often described as a burning or an uncomfortable, heightened sensation) that is not influenced by direct pressure, hip movement, or lower back movement. In contrast, lumbar radiculopathy, particularly involving L4-5, causes lateral hip pain that extends over a much wider area, radiating down the leg and into the foot, with or without associated foot numbnes.
ANTERIOR HIP OR GROIN PAIN — Anterior hip or groin pain suggests primary involvement of the hip joint itself. A gradual onset of pain in association with variable degrees of impaired movement is consistent with osteoarthritis. The differential diagnosis of acute onset of groin pain and impairment of weight bearing includes osteonecrosis (particularly in the setting of risk factors such as glucocorticoid use), occult fracture (eg, following trauma), acute synovitis, or, uncommonly, septic arthritis.
Anterior hip pain that is neither aggravated by direct pressure nor repetitive flexion of the hip suggests the presence of an inguinal hernia, lower abdominal pathology, or, less commonly, referred pain from higher lumbar spinal nerve roots (eg, L2-3).
POSTERIOR HIP PAIN — Posterior (gluteal) hip pain is the least common pain pattern affecting the hip. It is most often a sign of sacroiliac joint disease, lumbar radiculopathy, herpes zoster, or an unusual presentation of the hip joint. Patients with posterior hip pain often undergo extensive examination and radiographic testing of the back and hip in order to define a precise cause.
LOWER ANTERIOR THIGH PAIN — Patients presenting with lower anterior thigh pain pose the greatest clinical challenge. Primary disease of the hip joint, primary and secondary lesions of the upper femur, stress fracture of the femoral neck, and upper lumbar radiculopathy can refer pain to the lower thigh (or even the anterior knee). Unless the pain can be reproduced by passive rotation (hip joint), by applying torque to the thigh (femur), or by maneuvers designed to elicit radicular symptoms (eg, straight leg raising), most patients with lower anterior thigh pain require specific radiographic procedures to define a precise cause.
DIFFERENTIAL DIAGNOSIS
TROCHANTERIC BURSITIS — As mentioned, inflammation of the trochanteric bursa is one of the most common causes of hip pain. It is caused by an exaggerated movement of the gluteus medius tendon and the tensor fascia lata over the outer femur. Even subtle gait impairment can increase friction and pressure over the trochanteric process. Common gait abnormalities that may result in trochanteric bursitis include lumbosacral spine stiffness, leg length discrepancy, knee arthritis, and ankle sprain. Untreated, the normally paper thin bursal wall thickens, fibroses, and gradually loses its ability to lubricate the outer hip.
Patients typically complain of lateral hip pain, with point tenderness over the trochanteric bursa. The point of tenderness usually lies approximately one inch posterior and superior to the greater trochanter, and is located about 7.5 cm deep to the skin.
HIP OSTEOARTHRITIS — Osteoarthritis most commonly presents in patients over 40 years of age. The principal symptom associated with osteoarthritis of the hip is pain, which is typically exacerbated by activity and relieved by rest. With more advanced disease, pain may be noted with progressively less activity, eventually occurring at rest and at night.
In contrast to the lateral hip pain associated with bursitis, osteoarthritis usually presents with groin pain that is aggravated by movement rather than by direct pressure. Other key clinical features suggestive of osteoarthritis include internal rotation of less than 15 degrees, pain on internal rotation, morning stiffness (less than 30 to 60 minutes), and flexion less than 115 degrees.
MERALGIA PARESTHETICA — The lateral femoral cutaneous nerve, a pure sensory nerve, is susceptible to compression as it courses from the lumbosacral nerve plexus, through the abdominal cavity, under the inguinal ligament, and into the subcutaneous tissue of the thigh. Symptoms range from numbness and tingling (hypesthesia) to burning pain (paresthesia) over the upper outer thigh. Pain referred beyond the upper outer thigh or pain accompanied by impaired reflexes or muscular weakness suggests either trochanteric bursitis or lumbar radiculopathy.
OSTEONECROSIS — Osteonecrosis, also known as aseptic necrosis, avascular necrosis, ischemic necrosis, and osteochondritis dissecans, is a pathological process that has been associated with numerous conditions and therapeutic interventions. The mechanisms by which this disorder develops are not fully understood. However, compromise of the bone vasculature leading to the death of bone and marrow cells, and ultimate mechanical failure, appear to be common to most proposed etiologies. The process is most often progressive, resulting in joint destruction within three to five years if left untreated.
A variety of traumatic and nontraumatic factors contribute to the etiology of osteonecrosis. A definitive etiologic role has been established for some of these factors, but the majority is probable relationships. Corticosteroid use and excessive alcohol intake are reported to account for more than 90 percent of cases .
The most common presenting symptom of osteonecrosis is pain. Groin pain is most usual in patients with femoral head disease, followed by thigh and buttock pain. Weight-bearing and motion-induced pain are seen in most cases. Rest pain occurs in two-thirds of patients, and night pain in approximately one-third.
Early diagnosis of osteonecrosis may provide the opportunity to prevent collapse and ultimately the need for joint replacement. However, most patients present late in the course of the disease. Thus, a high index of suspicion is necessary for those with known or probable risk factors, particularly high dose steroid use. The diagnosis is made radiographically.
OCCULT HIP FRACTURE — An occult hip fracture (nondisplaced fracture of the femoral neck) can be difficult to diagnose. It should be suspected in patients with severe anterolateral hip tenderness, severe pain with even partial weight bearing, and intolerance to passive rotation of the hip. Routine hip x-rays can be normal in this setting; the patient must remain non-weight bearing if the diagnosis is suspected until MR imaging or serial examination of the hip rules out the diagnosis.
AORTOILIAC VASCULAR OCCLUSIVE DISEASE — Patients with aortoiliac occlusive disease (Leriche's syndrome) may complain of buttock, hip, and, in some cases, thigh claudication. The pain is often described as aching in nature and may be associated with weakness of the hip or thigh with walking.
Physical examination may reveal diminished pulses beginning in the groin area bilaterally, with occasional bruits over the iliac and femoral arteries. Other findings include muscle atrophy and slow wound healing in the legs. The examination of the hip joint and soft tissues are essentially normal.
REFERRED PAIN FROM THE LUMBOSACRAL SPINE OR SACROILIAC JOINT — The back and sacroiliac joints commonly refer pain to or through the hip. The lower lumbar roots refer pain through the gluteus and posterolateral thigh areas. Sacroiliac joints refer pain to the gluteal area. Referred pain from these locations should be suspected whenever back symptoms accompany the pain, the pain extends past the knee, paresthesias or hypesthesias accompany the pain, and the examination of the hip joint and soft tissues are unremarkable.

REFERÊNCIAS: http://www.uptodate.com/contents/evaluation-of-the-adult-with-hip-pain?source=search_result&search=CAUSES+OF+PAIN+hip&selectedTitle=1~83