What inspection should femoral head necrosis do?

Most patients with femoral head necrosis have normal laboratory results. When necessary, the following inspections can be carried out:

(1) Hemodynamic examination

① Intramedullary pressure measurement

Under local anesthesia or general anesthesia, the trocar was directly inserted into the medullary cavity of the intertrochanteric region of femur, and the intramedullary pressure of the diseased region was measured. Compared with conventional X-ray and radionuclide bone scanning, this method can find the abnormal changes of bone tissue earlier, which has certain value for the early diagnosis of femoral head necrosis.

② X-ray photography of intramedullary vein.

Human contrast agent is injected into the medullary cavity through a trocar for measuring the intramedullary pressure, and X-rays are taken continuously to observe the progress and emptying of the contrast agent in the medullary cavity, so as to check the running structure of blood vessels, which can provide basis for the early diagnosis of femoral head necrosis.

(2) Histopathological examination

It can be used as a basis for the diagnosis of femoral head necrosis. At present, it is rarely used alone, and it is often used simultaneously with bone marrow decompression and bone grafting.

(3) Imaging examination

①X-ray examination

It is the simplest and practical method to diagnose the disease, but its sensitivity is poor, and it is difficult to diagnose it only by X-ray in the early stage. The early stage of osteonecrosis is normal or mild osteoporosis, and the bone density in the lesion area can also increase relatively evenly. Then, wedge-shaped sclerosis zone or cystic lesions of bone tissue can be seen in the weight-bearing area, and a "crescent-shaped translucent zone" parallel to the articular surface appears, and the joint space is widened. Finally, the subchondral bone plate and articular surface collapsed, the bone contour changed, the step was discontinuous, the bone compression increased, the acetabular articular surface was also damaged, the joint space narrowed, osteophyte formed, and the whole joint showed degenerative arthritis changes.

② Radionuclide scanning

99mTc phosphate bone scanning has been used for the diagnosis of bone diseases for more than 20 years. The sensitivity of diagnosing osteonecrosis is as high as 80%, which can reflect the lesion earlier than routine X-ray examination.

③ Computed tomography (Cr) can reflect the changes of bone necrosis earlier than conventional X-ray examination and tomography.

④ Magnetic resonance imaging

When other tests are negative and ischemic necrosis is highly suspected, they should be examined. This is an ideal method for early diagnosis.

⑤ Fault scanning

As a supplement to routine X-ray examination, it has been used for many years, which can reflect the structural changes of bone tissue in more detail, especially in the absence of ct and magnetic resonance equipment, and has certain reference value for solving clinical difficult problems.