CT scan of hip is an X-ray tomographic examination of the joint of the lower limb with postprocessor computer processing of images and multi-plane reconstruction of the image. The acetabulum, the proximal epiphysis with the neck and head of the femur, the iliac bone, as well as the auxiliary apparatus of the joint fall into the scanning area. Contrast enhancement allows for a more detailed examination of the periarticular soft tissues, native research is more informative in the diagnosis of bone and joint pathology. CT has diagnostic value in detecting inflammatory processes, degenerative changes, ligament and tendon injuries, fractures, neoplasms of this area.
Scanning is prescribed to patients with suspected development of malignant or benign tumors of the proximal femur, acetabulum and surrounding soft tissues. CT scan of hip allows you to detect even small neoplasms at the preclinical stage. The method is also effective in detecting metastases. Tomographic examination is widely used in traumatology, because it makes it possible to diagnose fractures of the acetabulum, head and neck of the femur, including those that are poorly visible on conventional X-rays. With the help of CT, it is possible to assess the degree of damage to bone tissue, determine the number of fragments, the severity and direction of displacement of fragments and determine the tactics of treatment. Also, computed tomography is prescribed to patients before surgery and after surgical treatment of a hip fracture in order to assess the effectiveness of the intervention.
With the help of CT, it is possible to detect infectious processes – arthritis, osteomyelitis. This method of diagnosis is quite informative even if degenerative-dystrophic changes in the joints are suspected. Scanning is prescribed for patients with arthrosis, osteoporosis. Layered images of the pathological focus allow us to assess the extent of the lesion and, based on these data, determine the subsequent treatment regimen. This is one of the most informative methods of diagnosing congenital anomalies of the structure of this joint. CT is prescribed for suspected congenital hip dislocation and hip dysplasia. The technique is also used for Perthes disease, a pathology that develops against the background of a blood circulation disorder and leads to aseptic necrosis of the femoral head. To assess the work of blood vessels and the condition of the joint as a whole, it is more expedient to conduct a scan with the introduction of contrast fluid.
Due to X-ray radiation, CT of the hip joint is absolutely contraindicated for women during pregnancy. Due to the technical features of the tomograph, scanning is not carried out for patients with a body weight of 120-200 kg, it is in this range that the load capacity of various models of devices is located. The procedure is not recommended for children under 14 years of age and patients who cannot maintain a stationary body position for a long time. In case of vital necessity, manipulation is performed under anesthesia. The procedure with contrast is contraindicated in patients with severe renal insufficiency and in case of allergy to iodine preparations. A relative contraindication to the use of contrast is the lactation period. If necessary, a woman should stop breastfeeding within 2 days after the procedure.
A CT scan of hip is usually prescribed after undergoing a standard radiography. With native scanning, preparation by the patient is not required. If computed tomography is performed with the introduction of contrast, it is necessary to stop eating 6 hours before the start of the procedure. Immediately before starting the diagnosis, the patient should remove all metal objects, including metal-containing elements of clothing. Personal belongings can be left in a separate office. The patient should wear cotton underwear or a disposable medical gown.
Methodology of conducting
With CT scan of hip with contrast, the substance is administered by intra-articular injection or intravenously. The first option is used more often, as it allows you to visualize the soft tissues of the area under study well. Intravenous administration of the drug is advisable if it is necessary to assess the blood supply to the hip joint and identify tumors. In orthopedics and traumatology, this method is rarely used. Contrast in CT scan of hip is introduced immediately before starting the tomograph. Then the patient is placed on a mobile couch, which moves into the ring of the device. During the scan, the ring rotates around the patient’s body.
The data obtained during a CT scan of hip is transmitted to a computer, where it is processed using special software. During the procedure, the patient must maintain a stationary position, non-compliance with this rule may cause distortion of the images. The duration of the examination is about 5 minutes. With the introduction of a contrast agent, the scanning time increases to 20-30 minutes. During a CT scan of hip, the patient does not experience discomfort.
Based on the obtained images, the radiologist can establish the fact of the presence of neoplasms, traumatic injuries, foreign bodies, congenital anomalies, etc. It is possible to obtain the results of the examination after 1-2 hours. The patient is given a written opinion, printed pictures and (in some cases) images on digital media. These data should be transmitted to the attending physician to establish an accurate diagnosis and determine the further treatment regimen.
Comparing computer and magnetic resonance imaging, it should be noted that both methods allow to obtain layered images of the studied area. At the same time, MRI is more informative when studying soft tissues, whereas CT allows you to obtain data on the state of bone structures. During magnetic resonance examination, electromagnetic radiation is used, which does not pose a danger to the patient’s health, so the procedure can be repeated the required number of times. A CT scan of hip is allowed no more than twice a year. A less informative study compared to CT is standard radiography, which allows to obtain images in which the structures under study are superimposed on each other. With CT, the doctor can build a three-dimensional model of the joint based on a variety of layered images.