[Fissures of the posterior labrum and associated lesions: CT arthrogram evaluation]. / Fissures du labrum glénoïdal postérieur et lésions associées de l'épaule: une étude en arthroscanner.

PURPOSE: To describe osseous, chondral and tendinous lesions associated with fissures of the posterior labrum. To better understand the pathological processes leading to fissure of the posterior labrum. Materials and methods. Retrospective study of 43 CT arthrograms performed in 43 patients that showed a fissure of the posterior labrum. The following associated lesions were noted: osseous and chondral remodeling of the humeral head and/or glenoid and articular surface fissures of the rotator cuff. Based on type of associated lesions, patients were separated into one of four pathological subgroups: posterior instability, posterosuperior or internal impingement, anterior instability and isolated fissure of the posterior labrum. RESULTS: Sixteen patients (37.2%) of patients showed posterior instability, 12 (27.9%) showed lesions of internal impingement, and 11 (25.6%) showed lesions of anterior instability. Only 4 patients (9.3%) had an isolated fissure of the posterior labrum. CONCLUSION: Posterior instability, internal impingement and anterior instability are the main pathologies leading to fissure of the posterior labrum, which seldom occurs in isolation. Evaluation of these associated lesions allows understanding of the underlying pathological processes leading to fissure of the posterior labrum.

Study of the joint space of the hip on supine and weight-bearing digital radiographs.

AIM: To compare hip joint space on supine and weight-bearing anteroposterior digital radiographs. MATERIALS AND METHODS: Fifty anteroposterior views of the hip in 25 patients were taken in supine and weight-bearing positions on a fluoroscopic unit. Two observers in a double-blind study assessed the width of the joint space on an Easy Vision unit with an indirect method of measurement (metric index). RESULTS: Inter-observer and intra-observer variabilities of the metric index were less than 4.1%. There was no significant difference of the metric index of the hip (P>0.05), between supine and weight-bearing positions. CONCLUSION: There is no significant difference of the width of the joint space of the hip between supine and weight-bearing anteroposterior radiographs. Measuring joint space loss in osteoarthritis of the hip with anteroposterior views should be done with radiographs of the hip in the supine position to improve image quality.

Lumbar facet joint arthrography with the posterior approach.

Lumbar facet joint (LFJ) arthrography with intraarticular injections of long-acting steroids and local anesthetics is routinely used for therapeutic purposes in selected patients for relief of low back pain. The procedure may also be used for diagnostic reasons to establish the source of such pain. However, because direct access to the LFJ space is not always possible owing to degenerative changes such as osteophytes, another posterior approach has been proposed for LFJ arthrography. With the patient in the prone position, a spinal needle is inserted vertically into the inferior recess of an LFJ with fluoroscopic guidance and the patient under local anesthesia. To facilitate puncture, cushions are placed under the patient's abdomen to flatten normal lumbar lordosis, which enlarges the inferior recess of the LFJ. Use of cushions also results in a decrease in tissue thickness in the patient, thereby improving image quality and decreasing radiation exposure. LFJ arthrography can demonstrate the causative role of facet disease in abnormalities responsible for low back pain or sciatica and can be performed easily and rapidly with this direct posterior approach.

[Desmoid tumor of the thoracic wall. A case manifesting as painful stiffness of the shoulder]. / Tumeur desmoïde de la paroi thoracique. Un cas révélé par un enraidissement douloureux de l'épaule.

BACKGROUND: Desmoid tumors are uncommon fibromatous tumors arising from musculoaponeurotic tissue characterized by spindle cell fibroblast and myofibroblast proliferation. The cause is unknown (trauma, hormonal factors, genetic anomaly...). Locally invasive, they tend to recur increasing morbidity or even mortality. CASE REPORT: Stiff shoulder resulting from blockage of the scapulothoracic articulation was the inaugural sign. Three-phase bone scintigraphy demonstrated early uptake in the soft tissue in contact with the scapula. Magnetic resonance imaging and biopsy confirmed the diagnosis of desmoid tumor. Complete resection was performed. No adjuvant radiotherapy nor hormone treatment were given since no antiestrogen receptor antibodies were identified on the surgical specimen. DISCUSSION: The clinical manifestation (stiff shoulder) and the scapular localization observed in this case are unusual for desmoid tumors. Initially tendinopathy of the shoulder, acromio-clavicular arthropathy and capsular retraction of the shoulder joint had been entertained. Early diagnosis and wide surgical resection are indicated in desmoid tumors.

[MRI and articular cartilage]. / IRM et cartilage articulaire.

Although plain films are fundamental for routine imaging of degenerative chondral lesions, MRI is a promising tool of investigation for the articular cartilage. Its modalities are still imprecise and debated, but, because of its noninvasiveness, it is destined to be preferred over arthroCT. The small size of the cartilage requires thin slices of less than 3-mm thick. The various features of normal cartilage images must be well known. They depend on acquisition parameters, zonal structure of the cartilage and numerous artifacts (partial volume average, chemical shift, magnetic susceptibility, truncation, "magic angle"). Fast SE images provide a good compromise between contrast and the signal-to-noise ratio. T2-weighted images take advantage of an arthrographic effect in case of joint effusion. 3D GE images allow a more accurate evaluation with 1-mm thick slices. In all sequences, adding of a fat-suppression presaturation increases contrast between the cartilage and the surrounding structures. The diagnostic accuracies of the different sequences and of MR arthrography are discussed. Quantitative measurements of cartilage thickness and volume remain the topic of clinical research.

Longitudinal stress fractures of the tibia: comparative study of CT and MR imaging.

The aim of this study was to compare the performance of CT and MRI in the diagnosis of longitudinal stress fracture of the tibia (LSFT). A retrospective study of imaging findings was performed in 15 patients with LSFT. The CT and MR images were compared for detection of fracture line, callus, bone marrow edema, and soft tissues changes. The CT and MRI techniques allowed the detection of the fracture line in 82 and 73 % of cases, respectively. The callus was always visualized with CT or MRI. The MRI technique had a markedly higher sensitivity than CT in the detection of bone marrow edema (73 vs 18 %) and soft tissue lesions (87 vs 9 %). This may cause a misleading aggressive appearance on MRI. Computed tomography remains the best imaging modality for diagnosis of LSFT. However, MRI findings should be known to obviate the performance of CT or bone biopsy.

[Imaging]. / Imagerie.

The panoply of imaging techniques useful in podology is essentially limited to X-rays. Standard "standing" and "lying" X-rays furnish most of the required information. Arthrography is sometimes performed, in particular for trauma or tumour of the ankle. CT scan and MRI make a decisive contribution in difficult cases, notably in fractures and in small fractures without displacement. The two latter techniques are useful in tendon, ligament and muscular disorders, where echography is also informative. Rigorous analysis of radiographies and a good knowledge of foot disorders make these imaging techniques efficacious.

Image-Guided Spinal Steroid Injections.

This paper has been written to stimulate the radiologist to consider the various aspects of spinal steroid injections as therapeutic procedures. Special emphasis is placed on needle guidance, asepsis, and possible problems involved. It constitutes a highly practical and variously illustrated and informative guide for the choice of steroids and various spinal joint approaches. It details the following target areas: lumbar facet joints, cervical facet joints, costovertebral joints, C1-C2 joint, intervertebral discs, epidural space, and interspinous bursa. Safety is the key element of the above-mentioned techniques. The radiologist must pay special attention to the omnipresent risk of iatrogenic infection.