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Biomedical subjects

B Maldague

Publications and source records attributed to B Maldague.

At least 55 records · Page 3Linked to original sources

Epiphyseal impaction as a cause of severe osteoarticular pain of lower limbs after renal transplantation.

A syndrome of severe osteoarticular pain of lower limbs occurring early after renal transplantation (TP) has been recently identified. We describe its prevalence, clinical presentation and outcome. Symptomatic patients have been studied with conventional X-rays, magnetic resonance (MR) imaging, and 99mTechnetium scintigrams of the painful areas. Among 86 patients transplanted over a two-year period, nine (4 men, 5 women; mean age of 40.4 years; range 32 to 59) developed unexplained severe spontaneous osteoarticular pain of lower limbs 19 to 105 (mean 58) days after TP. Pain affected hip(s), knee(s), and/or ankle(s). Clinical examination was usually unremarkable. Favorable outcome was the rule; mean duration of pain was 86 (range 19 to 175) days. Radiographs were abnormal (joint swelling, patchy osteoporosis and/or periosteal reactions) in 41%, MR (epiphyseal fatty marrow replacement by edema and/or hemorrhages) in 83%, and bone scans (one to several epiphyseal foci of increased uptake) in 81% of the symptomatic examined areas. Among joints re-examined 9 to 12 months after resolution of the symptoms, X-rays showed periosteal reactions in 31%, and the bone scans disclosed persistent increased uptake in 53% of the joints, whereas epiphyseal MR abnormalities had completely disappeared in 86%. There was no difference in dialysis duration, post-TP weight gain, evidence of hyperparathyroidism, and steroid and cyclosporine doses between symptomatic and an appropriately selected group of asymptomatic patients. By contrast, serum alkaline phosphatase levels were transiently higher (at the onset of symptoms) in the symptomatic group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Intravertebral vacuum cleft: changes in content after supine positioning.

Sequential radiographic and magnetic resonance (MR) imaging examinations were performed in nine patients with an intravertebral vacuum cleft indicative of avascular necrosis. Progressive changes in the content of the cleft occurred within an hour after the patients were placed in a supine position. Initially, the cleft showed a gaslike pattern during extension of the spine, with a radiolucent band on radiographs and a signal void on MR images. Later, the vacuum phenomenon disappeared on radiographs, and a fluidlike high-signal-intensity pattern appeared on T2- or T2*-weighted MR images, suggestive of a slow fluid inflow within the intravertebral cleft. Because the recognition of a vacuum cleft in a collapsed vertebral body helps avoid confusion with malignancy or infection, it is important to search for this in examinations performed immediately after supine positioning.

Aged↗

Appendicular and vertebral bone mass in ankylosing spondylitis. A comparison of plain radiographs with single- and dual-photon absorptiometry and with quantitative computed tomography.

OBJECTIVE: We assessed the prevalence, severity, and anatomic distribution of ankylosing spondylitis (AS)-related osteopenia (OP). METHODS: We studied 70 patients (60 males, 10 premenopausal females) with AS (according to the New York criteria) to determine the frequency of OP. Bone mass was measured by plain radiographs of the spine, by single-photon absorptiometry (SPA) of the distal and midshaft of the radius on the nondominant side, by dual-photon absorptiometry (DPA) of the lumbar spine (L2-L4), and by quantitative computed tomography (QCT) of the lumbar spine. RESULTS: SPA values for the radius mass were normal in males and in females, both at the distal and midshaft sites. In contrast, spine radiographs showed diminished density of the vertebral bodies in 69% of the males and 50% of the premenopausal females. Two male patients had had a vertebral compression fracture, and one female patient had had two. DPA values for the spine mass were significantly diminished in the male patients compared with the controls, but not in the female patients. Males with less severe AS also had the largest reduction in lumbar bone mineral content. In patients with more severe disease, lumbar bone mineral content was not statistically different from that in controls. QCT of the lumbar spine performed in 10 patients disclosed low density of the trabecular bone of the vertebral bodies, more so in those with more severe AS and syndesmophyte formation and/or apophyseal joint fusion, which contrasts with the normal values on DPA in these patients. CONCLUSION: Male patients with AS have axial osteopenia. In those who have very severe AS with new bone formation, DPA demonstrates normal values as a result of two opposite trends: central osteopenia (as assessed from QCT) and peripheral new-bone formation, which transforms vertebral bodies into long bones. This could modify the mechanical resistance of the spine and account for the propensity for anteroposterior transvertebral and transdiscal fractures after trauma in AS.

Absorptiometry, Photon↗

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.

Bone Neoplasms↗

Avascular necrosis of the hip: comparison of contrast-enhanced and nonenhanced MR imaging with histologic correlation. Work in progress.

In 15 hips with typical signs of avascular necrosis of the femoral head on plain radiographs and magnetic resonance (MR) images, gadolinium-enhanced spin-echo and fat-suppressed MR images were obtained and compared with nonenhanced T1- and T2-weighted images. Both enhanced and nonenhanced areas were consistently detected in the abnormal femoral heads. Enhanced areas showed a low signal intensity (SI) on T1-weighted MR images obtained before contrast material was administered and an intermediate to high SI on T2-weighted images. Nonenhanced areas showed an SI either identical (pattern 1) or hypointense (pattern 2) to that of fat on both sequences. Histologic correlation (six resected femoral heads) helped confirm that enhanced and nonenhanced areas corresponded respectively to viable and necrotic tissue. In most cases, SI analysis of nonenhanced T1- and T2-weighted images allows the differentiation of hypervascularized viable tissue from hypovascularized necrotic tissue of the sequestrum.

Adult↗

Effect of dialysis membrane and patient's age on signs of dialysis-related amyloidosis. The Working Party on Dialysis Amyloidosis.

This 12 center study was designed to assess factors affecting the development and progression of beta 2-microglobulin amyloidosis in long-term dialysis. A total of 221 patients who were on hemodialysis for more than five years, and who were treated the entire time only with AN69, a biocompatible, highly permeable membrane, or cuprophane, a less permeable, poorly biocompatible membrane (Cell) were evaluated for time on dialysis, development of carpal tunnel syndrome, and cystic bone lesions. X-ray documentation was taken in a minimum of four of the six following joints: both hips, wrists and shoulders. The data demonstrate that patients treated solely by AN69 membranes display signs of bone amyloidosis less frequently than do those treated by Cell membranes. Age at onset of dialysis was found to have a striking correlation with the development of carpal tunnel syndrome and bone amyloidosis, while no significant influence was found for hyperparathyroidism, sex or year of first dialysis.

Acrylic Resins↗

Treatment of the vertebral crush fracture syndrome with enteric-coated sodium fluoride tablets and calcium supplements.

A cohort of 101 patients were treated with enteric-coated sodium fluoride tablets and calcium supplements. Vitamin D was also given in supra-physiologic doses in 70% of the cases. Lumbar bone mineral density (BMD), as measured by dual-photon absorptiometry, increased in a linear fashion up to four years, irrespective of the value of initial BMD and of the underlying condition, be it involutional osteoporosis (the vast majority), glucocorticoid osteoporosis, or even osteogenesis imperfecta. Estrogen replacement therapy (ERT) seemed to promote the fluoride-induced increase in lumbar BMD, as did the vitamin D supplements. Of these patients, 17% proved "resistant" to the therapy. There was no way of predicting who would be in this category. Compared with an age- and sex-matched control group, women showed significantly different behavior of their bone mass. In the control group, the losses were highly significant at the lumbar spine and at all three scanning sites of the forearm, as measured by single-photon absorptiometry. In contrast, the fluoride group had a significant gain of BMD at the lumbar spine and changes of BMC at the forearm were not significant. Fluoride thus preserved bone mass at the appendicular skeleton, while increasing it at the axial skeleton. When comparing the patients who received vitamin D supplements and those who did not, there was a significant difference in the appendicular skeleton. The distal forearm in the vitamin D-supplemented group tended to gain, whereas the midforearm lost significant bone mass. The trend was reversed in the group without vitamin D-supplementation, a more favorable pattern. Therefore, vitamin D supplements should not, as a rule, be provided to such patients. The biochemical hallmark of the fluoride-induced changes is a slight rise of the alkaline phosphatase within the normal range. Alkaline phosphatase levels that exceed the upper limit of normal signal a warning that too much fluoride and/or too little calcium supplements are being administered, or that a fluoride-related complication is impending or has occurred (e.g., a stress fracture). Osteosclerosis was achieved in 69% of the cases who had a radiological followup of at least four years (average period of appearance: 1.8 years). Stress fractures in the lower limbs occurred in 17 patients, almost exclusively in females, and appeared on average 2.2 years after initiation of therapy. In this group of stress fractures there was significant cortical bone loss at midforearm.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗

Transient cyst-like cortical defects following fractures in children. Medullary fat within the subperiosteal haematoma.

Asymptomatic cyst-like cortical defects appearing after fractures in children have been occasionally reported. Typically, these defects appear during fracture consolidation, within the newly formed subperiosteal bone, proximal to the fracture line, do not enlarge, and progressively disappear. We have previously shown a fatty density on CT scan within the early cortical defect. We now present two additional cases in which early CT scans appeared to confirm that these transient cortical defects may consist of fat, and probably result from the inclusion of medullary fat within the subperiosteal haematoma.

Adipose Tissue↗

[Medical imaging of Paget's disease].

Diagnostic imaging of Paget's disease of bone should provide more than a diagnosis. It should aim at assessing the distribution of the lesions, their degree of activity, their potential complications and their response to therapy. This goal can be reached by using simple methods (bone scintigraphy and conventional radiography), as long as one keeps in mind both the natural evolution of the disease and the changes it may show in case of superadded factors such as fissure-fractures, immobilization, and osteopenia. In clinical practice, bone scintigraphy is particularly apt to assess the distribution of the lesions, as well as their extent and degree of activity. Conventional radiography remains the best tool for establishing the diagnosis and the differential diagnosis of Paget's disease of bone, as well as for detecting its common complications, such as fissure fractures, diaphyseal bowing or superadded arthropathy. Additional methods such as CT should only be used when specific complications (such as spinal stenosis or superadded tumor) are suspected. In patients under antiosteoclastic therapy, careful sequential X-rays of one or two selected pagetic areas initially showing focal bone resorption represent a unique modality for monitoring focal treatment efficacy. Such therapy may indeed improve the biological parameters of the disease without correcting the negative bone balance within the most active lesions.

Bone and Bones↗

Depth insufficiency of the proximal trochlear groove on lateral radiographs of the knee: relation to patellar dislocation.

The depth of the trochlear groove was frequently noted to be insufficient in knees with patellar instability, particularly in the proximal portion of the trochlea. To confirm this observation, the depth of the trochlear groove of the femur was measured on lateral radiographs of 218 knees: 40 knees in 20 asymptomatic subjects, 116 knees in 69 patients undergoing radiography for various symptoms (96 without and 20 with patellar subluxation, determined on axial radiographs), and 62 knees in 34 patients who underwent surgery for recurrent dislocation or subluxation of one or both patellae (40 treated and 22 contralateral knees). In the 40 knees that had been operated on, the proximal trochlear depth (measured 1 cm below the upper limit of the trochlear groove) was 2.74 mm +/- 1.35, in contrast to 5.94 mm +/- 1.74 in the asymptomatic subjects and 5.84 mm +/- 1.53 in the patients with symptoms but no patellar instability. Recognition of depth insufficiency in the proximal portion of the trochlea should prompt a search for patellar instability. Axial views made with 30 degrees of knee flexion and lateral rotation of the leg are particularly helpful.

Adult↗

Patellofemoral joint: 30 degrees axial radiograph with lateral rotation of the leg.

A method for axial radiography of the patellofemoral joint has been developed that combines a forced lateral rotation of the leg with 30 degrees flexion of the knee. This view can be obtained without any special device and is definitely superior to the 45 degrees routine axial view in the detection of lateral subluxation of the patella. It should be obtained when patellar instability is suspected.

Femur↗

Spontaneous healing of aneurysmal bone cysts. A report of three cases.

We report three cases of spontaneous healing of aneurysmal bone cysts (ABC). In one case histological material was obtained after resection of the already ossified expansile mass discovered as a lytic lesion seven months previously. In the two other patients, spontaneous ossification of a radiologically presumed ABC in the lytic and expansile phase was observed after nine and seven months respectively. The healed lesions have remained stable at 12, 32, and 36 months respectively. These findings suggest that when the diagnosis can be made with confidence, and the lesion is in a location and at a stage that does not entail any risk of fracture or compression, expectant management should be considered. Our three patients were aged 22, 19 and 18 years, older than usual for developing ABC. This is also true for many of the few other reported cases of spontaneous or almost spontaneous healing and suggests that ABC has a greater tendency to stabilise in older patients.

Adolescent↗

[Radiology of patellar instability: contribution of the lateral radiography and the 30-degree axial view with external rotation].

Patellar instability is often missed by conventional axial views because transient subluxation of the patella essentially occurs during the first degrees of knee flexion (0 to 30 degrees), a position in which bilateral routine axial views are impossible to obtain. However, simple radiographic methods enable detection of both patellar instability and the often associated trochlear depth insufficiency. Every lateral radiograph of the knee depicts the depth of the proximal trochlear groove which is superior to 5 mm in a normal population. Upper trochlear depth insufficiency is frequently observed in the case of major patellar instability. Lateral views of the knee recorded during the first degrees of flexion (0 degrees-15 degrees) enable detection of patellar maltracking through the patellar tilt always associated with significant subluxation of the patella. Patellar maltracking may be studied dynamically by lateral fluoroscopy during progressive flexion of the knee. Unilateral 30 degrees axial radiographs with forced lateral rotation of the leg are definitely superior to conventional axial views in detecting transient patellar subluxation. These simple radiographic modalities should replace computed tomography in the search for patellar instability.

Humans↗

Effect of renal transplantation on the radiological signs of dialysis amyloid osteoarthropathy.

We have assessed the fate of amyloid bone cysts after a successful renal transplantation in 5 patients who had been on dialysis for 7 to 15 years. The size of 34 cysts, typical of amyloid osteoarthropathy, was monitored on annual X-rays for 29 to 75 (mean 47) months after TP. In sharp contrast to their progression during dialysis, cysts did not increase in size and no new cysts appeared during follow-up. However, despite a successful graft, none of the 34 cysts regressed significantly. The stability of the bone cysts may reflect either the poor solubility of the beta 2-m amyloid deposits or the limited accessibility of bone deposits to lytic factors. A longer follow-up will perhaps be necessary to document a significant regression of the cysts. Strikingly, transplantation resulted within a few days in an almost complete relief of articular complaints; in the absence of evidence of amyloid regression, this probably reflects the anti-inflammatory effect of steroids.

Adult↗

Pustulotic arthroosteitis and chronic recurrent multifocal osteomyelitis in children. Report of three cases.

We describe 3 children with pustulosis palmaris et plantaris associated with chronic recurrent (multifocal) osteomyelitis, located in the clavicle in 2 patients, and in the distal fibula as well as in several metatarsals in the third. The first 2 children also developed inflammatory sacroiliitis, one with chronic peripheral polyarthritis. These 3 cases represent the arthrosteitis and chronic recurrent multifocal osteomyelitis syndrome associated with palmoplantar pustulosis.

Arthritis↗