Jacques Malghem

The intravertebral vacuum cleft: a sign of ischemic vertebral collapse.

A gas-density cleft within a transverse separation of the vertebral body, appearing in extension and disappearing in flexion, was observed in 10 cases of vertebral collapse at the thoraco-lumbar junction. The patients were 55 to 83 years old (mean, 68) and 7 of them were on chronic corticosteroid therapy. Such an intravertebral cleft has not been found by the authors in vertebral collapse of tumoral, inflammatory, or traumatic origin and is thought to represent ischemic vertebral fracture. This sign could be helpful in the differential diagnosis of vertebral collapse in elderly patients.

Skeletal survey in advanced multiple myeloma: radiographic versus MR imaging survey

In an attempt to compare the sensitivity of bone radiographs and bone marrow magnetic resonance (MR) imaging for bone lesion detection in patients with stage III multiple myeloma (MM) and to evaluate the possible consequences of the replacement of the conventional radiographic skeletal survey (RSS) by an MR survey of the spinal and pelvic bone marrow in these patients, we obtained MR studies of the thoracic and lumbar spine, pelvis and proximal femurs in addition to the conventional RSS (including radiographs of the skull, entire spine, pelvis, ribs, humerus and femurs) in 80 consecutive patients with newly diagnosed stage III MM according to the Durie and Salmon staging system (based on blood tests and on the RSS). The performance of MR and radiographic studies to detect bone lesions in given anatomic areas and in given patients were compared. The consequences on MM staging following the substitution of the RSS by the MR survey were assessed.

Magnetic resonance imaging of the normal bone marrow

Abstract The bone marrow is a complex organ that contains fat and nonfat cells, the proportions of which vary greatly with age and in the different bones of the skeleton. Magnetic resonance (MR) imaging provides information on the composition of the medullary cavity of any given bone and on the distribution of red and yellow marrow in the skeleton. This article deals with the wide spectrum of appearances of the normal bone marrow at MR imaging.

Radiological manifestations of bisphosphonate treatment with APD in a child suffering from osteogenesis imperfecta.

A 12-year-old female suffering fromosteogenesis imperfecta (OI) was treated with 3-amino-1-hydroxypropylidene-1,1-bisphosphonate (APD) orally, 250 mg daily, for periods of 2 months, alternating with periods of 2 months of abstinence. Total duration of therapy was 1 year. Radiological and clinical improvement was striking. Furthermore, X-rays of the bones showed large, parallel radio-opaque striae, corresponding exactly to the periods of therapy. These were present in all metaphyses.

Benign osteochondromas and exostotic chondrosarcomas: evaluation of cartilage cap thickness by ultrasound.

Ultrasonography (US) enables accurate assessment of the cartilage cap of exostoses. The cartilage cap appears as a hypoechoic layer covering the hyperechoic surface of the calcified part. Measurements of cap thickness with US were compared with measurements performed on pathological specimens in 22 resected exostoses and 2 exostotic chondrosarcomas. The US measurements proved to be very accurate, with a mean measurement error of less than 2 mm for cartilage caps less than 2 cm thick. The detection rate and measurement accuracy of US were higher than with computed tomography (CT) and comparable to magnetic resonance imaging (MRI), which were available in 14 and 10 cases, respectively. US appears to be a good procedure for evaluating the cartilage cap, which is usually thin for a benign exostosis and thick for a malignancy. In addition, other complications — such as bursa formation — are easily recognizable. The sole limitation is that US cannot visualize the cartilage cap when it is inwardly orientated or deeply located in soft tissues, which are both, however, relatively uncommon situations.

End plate marrow changes in the asymptomatic lumbosacral spine: frequency, distribution and correlation with age and degenerative changes.

PurposeTo investigate the frequency and distribution of end plate marrow signal intensity changes in an asymptomatic population and to correlate these findings with patient age and degenerative findings in the spine.Materials and methodsMR imaging studies of the lumbosacral (LS) spine in 59 asymptomatic subjects were retrospectively reviewed by 2 musculoskeletal radiologists to determine the presence and location of fat-like and edema-like marrow signal changes about the end plates of the L1-2 through L5-S1 levels. The presence of degenerative changes in the spine was recorded as was patient age. Descriptive statistics were utilized to determine the frequency and associations of end plate findings and degenerative changes in the spine. Interobserver variability was determined by a kappa score. Binomial probability was used to predict the prevalence of the end plate changes in a similar subject population. The Fisher exact test was performed to determine statistical significance of the relationship of end plate changes with degenerative changes in the spine, superior versus inferior location about the disc and age of the patient population.ResultsFocal fat-like signal intensity adjacent to the vertebral end-plate was noted in 15 out of 59 subjects by both readers, and involved 38 and 36 out of 590 end plates by readers 1 and 2, respectively. Focal edema-like signal intensity adjacent to the vertebral end plate was noted in 8 out of 59 subjects by both readers and involved 11 and 10 out of 590 end plates by readers 1 and 2, respectively. Either fat or edema signal intensity occurred most often at the anterior (p<.05) aspects of the mid-lumbar spine and was seen in an older sub-population of the study (p<.05).ConclusionEnd plate marrow signal intensity changes are present in the lumbar spine of some asymptomatic subjects with a characteristic location along the spine and in vertebral end plates.

Multidetector spiral CT arthrography of the shoulder. Clinical applications and limits, with MR arthrography and arthroscopic correlations

Although MR imaging and MR arthrography are the first choice modalities for shoulder imaging, CT arthrography (CTA) may be used successfully to address many clinical questions. The advent of submillimeter multiple detector CT technology and subsequent excellent three-plane resolution has considerably increased the quality of CTA examinations and has propelled this technique to the forefront in a growing number of indications. The combined use of iodinated contrast material for fluoroscopic confirmation of the articular position of the needle before injection of gadolinium chelates for MR arthrography offers the unique opportunity to compare CTA and MRA findings in carefully selected cases. This paper illustrates capabilities and limits of CTA for the study of rotator cuff tears, shoulder instability, cartilage lesions, anatomical variants and abnormalities of the glenoid labrum, with correlations to MR arthrography and surgical findings.

Spiral CT arthrography of the knee: technique and value in the assessment of internal derangement of the knee.

Abstract. Computed tomography imaging has achieved excellent multiplanar capability and submillimeter spatial resolution due to the development of the spiral acquisition mode and multidetector row technology. Multidetector spiral CT arthrography (CTA) yields valuable information for the assessment of internal derangement of the joints. This article focuses on the value of spiral CTA of the knee in the assessment of the meniscus, anterior cruciate ligament, and hyaline cartilage lesions. Advantages and disadvantages of spiral CTA with respect to MR imaging are presented.

INJURY TO THE BRACHIAL PLEXUS BY A FRAGMENT OF BONE AFTER FRACTURE OF THE CLAVICLE

Clavicular fractures are occasionally responsible for lesions of the brachial plexus. The symptoms are usually delayed and due to compression by hypertrophic callus, nonunion or a subclavian pseudoaneurysm. We describe a patient in whom a displaced bone fragment was pressing on the retroclavicular part of the brachial plexus, leading to early symptoms of a lesion of the posterior cord. Internal fixation of the clavicle and external neurolysis of the brachial plexus gave an almost full recovery.

Dynamic radiologic patterns of Paget's disease of bone.

Within the diaphyseal cortex, the primary resorption phase of Pagets disease is often limited either to the endosteum or to the central layers of the cortex. This results in primary resorption fronts that are usually discrete, both radiologically and scintigraphically. The subsequent activation of the subperiosteal cortex may be delayed, leading to secondary expanding fronts associated with subperiosteal new bone formation. Sequential radiographs of 19 untreated patients followed 6.4 +/- 1.2 years showed that the mean extension rate of the lesions within cortical bone was 8 +/- 0.5 mm/year per advancing front. This extension rate showed no significant change in 15 patients treated with calcitonin (CT) and/or ethane-1-hydroxy-1,1-diphosphonate (EHDP), but was significantly decreased in 14 patients treated with 3-amino-1-hydroxypropilidene-1,1-diphosphonate (APD). The increased remodeling rate of pagetic bone magnifies the radiologic changes due to mechanical, dystrophic, and metabolic interferences. Thus, a sclerotic pattern of the disease may rapidly change into a mixed or even a lytic pattern under the influence of any rarefying factor. Conversely, lytic pagetic bone may transform into dense bone through the administration of antiosteoclastic medications such as CT and APD. The reconstructive action of any new therapeutic regimen should be monitored radiologically.