Cysts of the glenoid labrum are ganglia cysts extending near the glenohumeral joint with frequent clinical signs and symptoms of a compression of the subscapularis nerve. They are detected through MR examination. They are frequently associated to instability of the glenohumeral joint.
Since no true roetgenographic lateral view of the hip is available, several different additional views of the hip have been described to complete the analysis obtained on the AP view. These different additional views of the hip are presented as well as their indications depending on the clinically suspected hip disease.
An X-ray examination can sometimes be performed during the first few days of pregnancy. To prevent these accidental irradiations of the fetus, women must receive specific information about radiation effects, the ten Day Rule must be respected, and the physician must choose a non irradiating technique. X-ray examination may be performed in an emergency, especially if the examination is far from the pelvis. The radiologist must optimize the constants and decrease the number of films. The dose received depends on mAs, but other parameters are necessary for calculation (film source distance, kV, filtration...). For computed tomography, slice thickness, and interval between slices are taken in account. The dose received reaches a maximum after three axial sections, but is higher for a given area, than with conventional radiography. The irradiation effects depend on the fetal dose and the stage of pregnancy. Before implantation, the fetal dose is either ineffective or induces a miscarriage. During organogenesis, between the second and 16th week, doses exceeding 500 mGy can cause death of the fetus, malformations or growth retardation. We consider that when the dose is less than 100 mGy, they are no reasons to terminate the pregnancy. MRI does not seem to be dangerous for the course of pregnancy. No studies have demonstrated any teratogenic effects with intense magnetic fields.
Myositis ossificans circumscripta (MOC) is a benign proliferation of fibrous tissue with large amounts of bone within soft tissues. Its clinical and radiological course is described and the value of CT and MR imaging is emphasized. Differential diagnosis includes soft tissue hematoma, infection or tumor. Florid reactive periostitis of the phalanges, turret exostosis, bizarre periosteal osteochondromatous proliferation in the hand and fibro-osseous pseudotumor of the digits are also described.
The authors emphasize the misleading images of lumbar myelography encountered in common vertebral diseases: disk disease, posterior interapophyseal joint diseases, degenerative and narrow spinal canal, in which dynamic views in the upright position represent the most original contribution of lumbosacral myelography as compared to new techniques. The authors also describe the postoperative appearances observed on lumbosacral myelography and some rarer diseases which must not be missed, such as epidural arachnoid cysts and epidural lipomatosis.
Calcific deposit within soft tissues is frequently a clue for diagnosis. The radiological analysis of a calcific deposit within soft tissues includes the following aspects: the basic structure of the calcification, the grade of differentiation of the calcification, the site of the calcification, the number of calcific deposits, the shape of the calcification, the changes in the adjacent non-calcified soft tissues and in the adjacent bone, the course of the clinical signs, the course of the radiological abnormalities.
Injuries of the medial collateral ligament (MCL) of the knee are easily diagnosed on clinical grounds. These lesions are generally treated conservatively. Radiological examinations are generally unhelpful. However, injuries of the MCL may be associated with those of many other ligaments of the knee in the case of complex strain of the knee so that the clinical diagnosis may be challenging; in some cases, surgical repair of associated lesions is indicated. In these cases of multiple ligamentous injuries, a radiological study of ligamentous abnormalities may be of interest. The anatomical background and the different radiological findings including those of X-rays, US, arthrography and MRI, obtained in patients with injuries of the MCL, are described; radiological differentiation of ruptures of the MCL with or without knee instability is emphasized.
Recurrent instability of the shoulder may sometimes be a difficult diagnostic challenge. Bernageau's standard X-rays set, which includes 3 antero-posterior X-rays with medial rotation and 2 glenoid views, is able to confirm the existence of anterior instability events. However, it gives no information on the glenoid labrum and the glenohumeral ligaments. As surgical techniques are more sophisticated, more precise imaging techniques are needed in order to adapt the surgical technique to the anatomical lesions. Although CT arthrography is today the best imaging technique to choose a surgical technique, it will probably be replaced by MR arthrography in the near future. Pros and cons of each imaging techniques are described, together with their implications for the choice of treatment.
Palmoplantar pustulosis and severe acne are sometimes associated with aseptic skeletal lesions, but such skeletal conditions can be observed without skin lesions. The acronym SAPHO (Synovitis, Acne, Palmoplantar pustulosis, Hyperostosis, Osteitis) has been suggested for this cluster of manifestations. The most frequent site of the disease is the upper anterior chest wall, characterized by predominantly osteosclerotic lesions, hyperostosis, and arthritis of the adjacent joints. Osteosclerosis of the vertebral bodies, hyperostosis, and erosions of the vertebral plates can be encountered. Unilateral sacroiliitis of frequently observed. Long bone involvement consists of osteosclerosis or osteolysis with periosteal new bone formation. Peripheral arthritis is rarely associated with joint destruction. The pathogenesis of this syndrome remains unknown, but a link with seronegative spondylarthropathies is probable. Awareness of the SAPHO syndrome should facilitate proper diagnosis and treatment.
The different lesions of the glenoid labrum are described. They may involve the antero-inferior, the posterior or the superior (SLAP lesions) part of the labrum. CT-arthrography is the gold standard imaging modality in this field of shoulder abnormalities.
The hand is a major site of musculoskeletal disorders. Clinical features to be studied include the patient's age and sex, pain, stiffness, range of motion of the various joints of the wrists and hands, soft tissue swelling (particularly tendons sheaths), bone excrescences, skin changes. Radiological abnormalities in the hands, if any, may confirm the clinical diagnosis. The main features of rheumatoid arthritis, systemic lupus erythematosus, psoriatic arthritis, erosive degenerative changes, Südeck syndrome, calcium pyrophosphate dihydrate deposition disease, etc., are reviewed.
Cysts of the glenoid labrum are ganglia cysts extending near the glenohumeral joint with frequent clinical signs and symptoms of a compression of the subscapularis nerve. They are detected through MR examination. They are frequently associated to instability of the glenohumeral joint.
After a brief review of the pertinent anatomy of joint compartments and main ligaments of the wrist, the authors present the technique of wrist arthrography and CT arthrography. They discuss the normal and pathological patterns. The main indications are the chronic painful wrist and posttraumatic wrist. Imaging can reveal ligament defects (particularly scapholunate ligament, or lunotriquetral ligament), triangular fibrocartilage tears, capsular defects, cartilage thinning, foreign bodies, synovial ganglia or synovitis of the wrist.
Apatite calcifications may be responsible for unusual aspects. Clinically they may mimick sepsis or soft tissue tumor, and radiologically a bone tumor or soft tissue tumor-like lesion with respect to the erosion of the bone cortex adjacent to an unusual calcification. Diagnosis is based on knowledge of atypical sites of calcification, CT, and mainly, radiological regression of the calcification after a short follow-up.
The diagnosis of localized osteolysis (synonym: bone cyst, defect) must be analytical. The site, size, and shape of the defect, its limits, assessed according to the Lodwick classification, reflect the activity of the lesion, the type of any periosteal reaction and the presence of a soft tissue mass are analysed successively. Based on these criteria and the clinical and laboratory characteristics, the image can be classified as quiescent or active, allowing guidance of management.
Physics of the radiographic exposition are presented, including those of the radiating image, contrast, sensitometry. Based on these principles, the modifications which allow correcting over- and underexposition of the images are explained.
Stress fractures of the tibia may disclose a longitudinal orientation which is obvious at bone scanning; a mild periostosis may appear on plain films; CT demonstrates a radially-oriented fracture in one aspect of the diaphyseal cortex. A cortical dissection-like vertically oriented insufficiency fracture may involve the medial aspect of the femoral shaft underlying the lesser trochanter; the fracture is concentric to the femoral cortex at CT. Insufficiency fractures of the sacrum may be misdiagnosed on plain films; bone scanning displays a typical H-shaped increased uptake which is a specific pattern. Insufficiency fractures of the pubis may appear as tumoral bone destruction; however no soft tissue mass is present at CT which in addition demonstrates normal fat tissue abutting the osseous lesion.
The main characteristics and the relative interest of the different modalities of medical imaging digitalization are presented as well as their most appropriate clinical indications.
Cervical myelography is obtained after injection of contrast medium into the lumbar subarachnoid space through a lumbar puncture. The patient is prone with a large radiolucent block under the pelvis so that the site of lumbar puncture is at a higher level than that of the cervical spine lordosis. Lumbar contrast is injected gently so that the contrast fluid slides along the ventral aspect of the dural sac and immediately reaches the cervical subarachnoid space. Then AP and lateral (with a horizontal X-ray beam) views are obtained. The patient has to remain firmly immobilized during the whole procedure to avoid blending of the contrast medium with CSF. This procedure is safe and allows cervical myelography to reach the same quality as that obtained through cervical puncture.
