Early Diagnosis Of Avascular Necrosis Research Articles

Avascular Necrosis and Subchondral Collapse of the Femoral Head After Intra-Articular Corticosteroid Injection: A Case Report

A 51-year-old female with no history of chronic alcohol or steroid use presented with right hip pain. X-ray and magnetic resonance imaging (MRI) showed osteoarthritic changes without evidence of avascular necrosis (AVN) or subchondral collapse of the femoral head, and the patient elected to receive an intra-articular corticosteroid injection to address the pain. She returned four months post-injection, reporting the pain had returned after 2-3 months of relief and was more severe than pre-injection. She opted for a second corticosteroid injection, but the procedure was stopped when heme was aspirated from the joint. A repeat MRI showed secondary femoral head AVN and subchondral collapse. Conservative management failed, resulting in a total hip arthroplasty (THA). This case highlights the importance of follow-up to detect warning signs of femoral head AVN after corticosteroid injection, such as rebound pain. Early diagnosis of AVN may prevent the progression and need for THA.

Kohler Disease: Diagnoses and Assessment by Bone Scintigraphy

Limping is a frequent occurrence in children and may be caused by various conditions, including trauma, inflammation, infection, and malignancy. Nontraumatic avascular necrosis of the tarsal bones should be included in the differential diagnosis. Accumulated data have supported the superiority of bone scans to radiography in the early diagnosis of avascular necrosis. Bone scintigraphy is a useful tool for investigating pain when symptoms, laboratory examinations, and radiography do not point to a specific diagnosis. In the early phase of disease, bone scans may demonstrate decreased tracer uptake (photopenic region), subsequently a hot area is seen during the reparative process. Although magnetic resonance imaging has important implications in the diagnosis of avascular necrosis, bone scintigraphy with its ready availability has a significant role as a primary tool in the evaluation of a limping child.

Evaluation of magnetic resonance imaging in the diagnosis of osteonecrosis of the femoral head. Accuracy compared with radiographs, core biopsy, and intraosseous pressure measurements.

The accuracy of magnetic resonance imaging in the detection of osteonecrosis of the femoral head was compared with that of other diagnostic methods in current use: plain radiography, bone-marrow pressure determinations, intramedullary venography, and histological examination of core-biopsy bone specimens. In the first phase of the study, forty-eight patients (ninety-six hips) who were at high risk for avascular necrosis were studied. Abnormal patterns on magnetic resonance imaging, consistent with those seen in necrosis, were found in all hips that were suspected of having Ficat Stage-2 or 3 changes on the basis of radiographic evidence of the disease. Abnormal patterns on magnetic resonance imaging that were characteristic of avascular necrosis were also observed in 17 per cent of the hips that were suspected of having Ficat Stage-0 changes and in 64 per cent of those that showed Stage-1 changes, all with no radiographic changes. In the second phase of the study, twenty-three of the ninety-six hips that were suspected of having early-stage necrosis of the femoral head but showed slight or no radiographic changes were studied by repeat radiographs, Ficat functional evaluations of bone, core biopsies of the femoral head, and magnetic resonance imaging. Of the twenty-three hips, eighteen (78 per cent) had positive changes on magnetic resonance imaging; nineteen (83 per cent) had positive histological evidence of necrosis; and fourteen (61 per cent) had positive findings by bone-marrow pressure studies and intramedullary venography. Although false-negative and false-positive results were observed with magnetic resonance imaging, the over-all results of this study suggest that magnetic resonance imaging may be useful for the early diagnosis of avascular necrosis.

Diagnosis of Ischemic Necrosis of the Hip-Reply

In Reply.— I would like to make a brief comment on the use of radionuclides in the early diagnosis of avascular necrosis from any cause. There is no consensus on which is the best way to image a femoral head. Dr Easton uses technetium Tc 99m sulfur colloid scanning and gives a reference to one article published in 1977. Although it appears that few other people use this technique, I am grateful that he drew our attention to it. In the two years since I originally wrote my article, nuclear medical techniques have advanced considerably. In our institution we are now using technetium Tc 99m pyrophosphate and taking blood pool types of image using pinhole views immediately after injection as well as taking delayed images. This technique seems to be much more accurate than the previously used techniques in the early diagnosis of avascular necrosis of the femoral head.

Radionuclide patterns of femoral head disease

The pattern of uptake of bone marrow specific radio- 99 m Tc sulfur colloid and the pattern of uptake of bone mineral specific radio- 99 m Tc pryophosphate may be valuable in assessing bone vascularity in diseases suspected of causing impaired blood supply, or indicate the presence of reactive bone formation. The low energy of the technetium label has been shown to be superior to 18F and 85Sr, and leads to greater imaging detail on the scans. Femoral head scanning with mineral and/or marrow specific radionuclides offers the clinician a method of evaluating the status of the femoral head and possibly an early diagnosis of avascular necrosis before roentgenographic changes occur. This study, which reports on a 5-year experience using radionuclide scanning to assess femoral head vascularity, begins with baseline or normal studies followed by variations of the normal pattern. Typical scan patterns of hip pathology described above are also presented.

THE USE OF RADIOACTIVE PHOSPHORUS IN THE DIAGNOSIS OF AVASCULAR NECROSIS OF THE FEMORAL HEAD

1. The pathology of avascular necrosis of bone and its relationship to the radiographic changes are considered briefly. 2. The inadequacy of radiographic examination in the early diagnosis of avascular necrosis is stressed. 3. Methods of early assessment of the residual vascularity of a bone mass are discussed. 4. Details of the principles, methods, and results of using radioactive phosphorus in the diagnosis of avascularity of bone are described. 5. The dangers and technical difficulties of using radioactive substances are discussed. 6. The possibility is envisaged that surgeons may soon be able to determine at the time of emergency operation whether the femoral head is dead or alive.