Genetics of patella hypoplasia/agenesis

The patella is a sesamoid bone, crucial for knee stability. When absent or hypoplastic, recurrent knee subluxations, patellofemoral dysfunction and early gonarthrosis may occur. Patella hypoplasia/agenesis may be isolated or observed in syndromic conditions, either as the main clinical feature (Nail-patella syndrome, small patella syndrome), as a clue feature which can help diagnosis assessment, or as a background feature that may be disregarded. Even in the latter, the identification of patella anomalies is important for an appropriate patient management. We review the clinical characteristics of these rare diseases, provide guidance to facilitate the diagnosis and discuss how the genes involved could affect patella development.

Botulinum toxin treatment of pes cavovarus in a child suffering from autosomal recessive axonal Charcot-Marie-Tooth neuropathy (AR-CMT2)

In a 12-year old girl suffering from autosomal recessive axonal Charcot-Marie-Tooth (CMT) neuropathy, pes cavovarus was treated with botulinum toxin injection in the tibialis posterior. The patient underwent a clinical evaluation, video analysis of spatiotemporal gait parameters and dynamic foot plantar pressure assessment before treatment and then two weeks, three months and six months thereafter. The video gait analysis revealed a decrease in varus during the swing phase of gait. The dynamic foot plantar pressure decreased by 50% in the excessive pressure at the side of the foot six months after the injection (maximal pressure=42.6N/cm2 before treatment and 18.9 N/cm2 after 6 month). Botulinum toxin injection appears to be an efficacious means of correcting pes cavovarus in CMT disease. A larger-scale clinical trial is now required to evaluate the putative longer-term preventive effect of this treatment on the pes cavus deformity.

Progressive anterior vertebral fusion: a report of three cases

We report a series of three cases of progressive anterior vertebral fusion diagnosed and monitored in our establishment. This very rare condition was discovered in young children while exploring a spinal deformity. With X-rays of the thoracolumbar spine it was possible to make a positive diagnosis and ensure follow-up. The radiographic semeiotics are characteristic and combine anterior pinching of the disc, well-delimited erosion of the anterior vertebral corners and anterior then posterior intervertebral ankylosis. MRI is very useful for assessing the extent of the intervertebral ankylosis and the condition of the residual discs, without irradiation. The condition develops over several months or years. Conservative treatment is usually sufficient.

[Plain radiographs of the wrist and hand]

The purpose of this review is to describe the value of the different radiographic projections of the wrist and hand, provide criteria for quality control and key interpretation points. Plain radiographs of the hand and wrist are still, in this era of cross-sectional imaging, of great importance in the assessment and understanding of bone and joint disorders, particularly in the setting of trauma. Indeed postero-anterior and lateral views have to be completed with additional projections depending on the suspected lesion and clinical presentation.

Les tendons : lésions inflammatoires et dégénératives

Tendons may be affected by a variety of pathologic conditions, including those caused by overuse and inflammatory diseases. Sonography is a very sensitive means of detecting tendonous pathology because of its spatial resolution and its comparative and dynamic capabilities. Moreover its wide availability makes it the preferred first-line imaging modality in these cases. This paper reviews the inflammatory and degenerative conditions that may involve the tendons and their sonographic appearances.

Normal anatomy of the heel entheses: anatomical and ultrasonographic study of their blood supply

The purpose of this study was first to determine the normal blood supply of the heel entheses with cadaver injection, and second, to identify by means of ultrasound (US) this blood supply in healthy volunteers before and after the intravenous injection of a US contrast agent (SonoVue). Twenty cadaver lower limbs were cut into sagittal, coronal, or axial sections after the injection of a red-colored gelatin solution. Ten anatomical samples were selected for histology. Then 10 healthy volunteers were enrolled in a contrast-enhanced ultrasonography study (CUS). Calcaneal tendon and plantar aponeurosis entheses were studied first without any contrast-agent (B-mode, power Doppler). A single dose (2.4 ml) of the contrast agent was then administered for studying each enthesis of the right foot. The operators had to look for blood flow within the entheses and in the adjacent soft tissues. Anastomotic transverse branches were seen macroscopically at the back of the calcaneal tendon, giving some capillaries penetrating the enthesis. None of these vessels could be seen with CUS. In contrast, a high-density vascular network could be detected in Kager's triangle with CUS. No blood vessel could be seen within the plantar aponeurosis enthesis, either macroscopically or microscopically. No evidence of entheseal vascularization was found with any contrast-enhanced imaging technique. Inferior branches of the lateral plantar artery were seen on coronal and sagittal sections of the hindfoot, and could be detected with CUS. These arterioles were running toward the anterior aspect of the calcaneal tuberosity, near the plantar aponeurosis insertion. In conclusion, no vascularization was detected with CUS at the cortical bone insertion of normal heel entheses. However, some vascularization could be seen in the immediate vicinity of heel entheses. The latter feature has to be kept in mind, as it may represent a pitfall for the diagnosis of early inflammatory changes in patients, especially those with seronegative spondylarthropathies.

Relationship between computed tomographic image analysis and histomorphometry for microarchitectural characterization of human calcaneus

The present study aimed to characterize the relationships between several variables reflecting bone microarchitecture assessed by both computed tomographic (CT) image analysis and histomorphometry (conventional CT system) at the calcaneus. A total of 24 cadaveric specimens were studied. The mean age at death was 78 +/- 10 years (range, 53-93 years). A total of 15 sagittal sections (1 mm in width and spaced 2 mm apart) were selected for CT analysis; 6 undecalcified sections (7 microm) were analyzed for histomorphometry. The histomorphometric analysis was performed on a Leica Quantimet Q570 image analyzer. Features measured by both methods were: bone volume/tissue volume (BV/TV), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), trabecular number (Tb.N), interconnectivity index (ICI), number of nodes (N Nd), number of terminus (N Tm), node-to-node strut count (NNS), node-to-terminus strut count (NTS), terminus-to-terminus strut count (TTS), marrow space star volume (SV), Euler number (EN), and fractal dimension (FD). The coefficient of correlations' values (simple linear regression) between histomorphometry and CT image analysis varied according to the parameters selected. R values were high for BV/TV, Tb.N, and Tb.Sp (range, 0.69-0.90; P < 0.01). R values were less significant for some variables also obtained from the binary image: SV (0.5, P < 0.05) and EN (0.43, P < 0.05). Finally R values were also significant for (two) variables obtained from skeletonized images, i.e., N Nd (0.4, P < 0.05) and N Tm (0.61, P < 0.01). Other correlations were not statistically significant. Moreover, for some variables the relationships between the two methods (CT analysis and histomorphometry) seemed best-described by using nonlinear models. For example, a logarithmic model was more appropriate for SV (r = 0.71, P < 0.01), N Nd (r = 0.52, P < 0.01). Finally the relationship between apparent (App) N Tm and N Tm was most satisfying when using an exponential model (r = 0.64, P < 0.01). In conclusion, trabecular bone structure measures determined on CT images show highly significant correlations with those determined using histomorphometry. The level of correlation varies according to the type of method used for characterizing bone structure, however, and the strongest correlations were found for the most basic features (Parfitt's parameters). Finally, for some variables, nonlinear models seem more appropriate.

Does quantitative ultrasound of bone reflect more bone mineral density than bone microarchitecture?

Relationships among quantitative ultrasound of bone (QUS), bone mineral density (BMD) and bone microarchitecture have been poorly investigated in human calcaneus.Twenty-four specimens, from 12 men and 12 women (mean age 78 +/- 10 years; range 53-93), removed from cadavers were studied. The feet were axially sectioned above the ankle. Two variables were measured for QUS (Achilles, Lunar): broadband ultrasound attenuation (BUA) and speed of sound (SOS). A third variable, the stiffness index (SI), which is a combination of both BUA and SOS, was also calculated. BMD (a lateral view) was measured on a QDR 2000 densitometer (Hologic). Bone microarchitecture was assessed by computed tomography (CT) using a conventional CT-system. Fifteen sagittal sections (1 mm in width and 2 mm apart) were selected for CT. Methods used for characterizing bone microarchitecture consisted in structural (trabecular network characterization) and a fractal analyses. The relationships between QUS and bone microarchitecture were assessed by simple linear regression analysis with and without adjustment for BMD (partial correlation) and by backward stepwise regression analysis. Strong relationships were found between BMD and QUS. Adjusted r(2) values were 0.545 for SOS and 0.717 for SI. Two microarchitectural variables were also significantly correlated with both SOS and SI: apparent trabecular separation (App Tr Sp) and trabecular bone pattern factor (App TBPF). After adjustment for BMD few correlations between QUS and microarchitectural variables were always significant. Adjusted squared semipartial coefficients of correlation (rsp2) values between SOS and bone microarchitecture were 6%, 6.8%, 13.2% and 4.6% for App BV/TV, App Tr Sp, App TBPF and fractal dimension (FD), respectively. For SI, corresponding figures were 3.7%, 4.1%, 5.2% and 3.2%. Backward stepwise regression analysis using BMD and microarchitecture showed a slight increase of r(2) values that varied from 8.4% for SI to 17.8% for SOS, compared with BMD alone. The current study suggests that although BMD is a major determinant of acoustic properties of human calcaneus, significant density independent relationships with bone microarchitecture should also be taken into account.

[Pseudo-winging of the scapula and snapping scapula secondary to solitary exostosis: two cases]

Pseudo-winging of the scapula and scapular snapping are two clinical signs of upper girdle insufficiency. The association of these two signs is highly suggestive, if not pathognomonic, of exostosis of the ventral aspect of the scapula. Resection of the exostosis is recommended to prevent pain and sarcomatous degeneration.

Multi-fasciculated anterior talo-fibular ligament: reassessment of normal findings

The aims of this study were to (a) provide an accurate description of the anterior talo-fibular ligament (ATFL) multifasciculated feature by means of cadaver study, and (b) to further delineate contour and signal variations on MR images related to this feature in a group of asymptomatic subjects. After MR imaging, three cadaveric feet were frozen and cut in the coronal plane. The ATFL were harvested and sent to pathology. Another cadaveric foot was dissected. The MR imaging was performed in 3 healthy volunteers and 19 patients without pathology of the ATFL. For both cadaveric feet and subjects, MR imaging protocol consisted of axial and coronal proton-density (PD) and T2-weighted turbo-spin-echo (TSE) sequences (TR/TE: 3500 ms/17-119 ms). On MR images, ATFL signal and fascicle numbers were assessed, respectively, in the axial and coronal planes. Gross anatomy and pathology confirmed the ATFL bifasciculated aspect. On cadaveric coronal MR images, 3 of 4 ATFLs were bifasciculated and one of four was striated. On patients' coronal MR images, 2 of 22 of the ATFL were monofasciculated, 12 of 22 bifasciculated, and 8 of 22 striated. On axial MR images, 16 of 22 of the ATFL demonstrated a low signal intensity and 8 of 22 an intraligamentous subtle increased signal intensity. Two of 22 of the ATFL had contour irregularities. Isolated anterior talo-fibular intraligamentous signal abnormalities or contour irregularities on axial PD and T2-weighted MR images with an otherwise normal ATFL aspect on coronal MR images and no other MRI criteria for ankle sprain may reflect normal anatomy.

[Value of US imaging of metacarpophalangeal joints in patients with early rheumatoid arthritis]

Technological advances in the field of ultrasound imaging may have, especially in metacarpophalangeal joints, an impact on decision making in patients with early rheumatoid arthritis. First, the normal anatomy of the metacarpophalangeal joints is briefly reviewed. Then, the authors describe the main ultrasound imaging findings of early RA. The role of ultrasound imaging in the assessment of therapeutic response as well as the benefit of microbubble ultrasound contrast agents are considered.

[Reproducibility of CT scan evaluation of muscular fatty degeneration. Intra- and interobserver analysis of 56 shoulders presenting with a ruptured rotator cuff muscles]

PURPOSE OF THE STUDY

This study was undertaken to determine the reproducibility of measurements of fatty degeneration of the rotator cuff using computed tomography (CT).

MATERIAL AND METHODS

Fifty-six patients who had undergone surgery for rotator cuff tear were included in this retrospective study. The extent of fatty infiltration was evaluated on CT scans with soft tissue windows in all 56 shoulders using a five-stage scoring system described by Goutallier. Five independent observers made the assessments. The same operation was repeated one month later to test intraobserver agreement. Four parameters were recorded: fatty infiltration of three muscles (supraspinatus, infraspinatus, subscapularis), and overall fatty infiltration grading. Interobserver variability was determined for each parameter using the intercorrelation coefficient (a test of reproducibility of quantitative measurements).

RESULTS

The most reproducible measurement was the overall fatty infiltration grade. For this parameter, interobserver agreement was good with an intercorrelation coefficient of 0.75. The interval of confidence was +/- 0.5. Intraobserver agreement depended on the observer's level of experience. It was good for overall fatty infiltration grade assess by three senior observers (r=0.78) and moderate for two junior observers.

CONCLUSION

The overall fatty infiltration grade is a reproducible parameter that should be used to evaluate the degree of fatty infiltration as the safety margin of this value (graded 0 to 4) is about 0.5. Fatty infiltration of a torn cuff would not be the only criterion to improve indications for treatment of rotator cuff tears.

[Camptocormia: a sign of axial myopathy. Report of 7 cases]

PURPOSE

Camptocormia or progressive lumbar kyphosis is an anterior bend of the trunk. It appears in orthostatism or while walking and is reducible in the decubitus position. It concerns patients older than 60 years of age. It is due to a fatty degeneration of the paravertebral muscles, although the physiopathology remains unclear.

METHODS

We report seven cases of camptocormia revealing authentic myopathies.

RESULTS

Our observations concern five women and two men of 55 to 72 years of age. All patients present lumbar kyphosis and had a fatty involution of the paraspinal muscles on the muscular MRI. Four patients fulfilled the Bohan and Peter criteria of polymyositis and dermatomyositis. In the other cases paravertebral muscular biopsies led to the diagnosis of a congenital myopathy, a mitochondrial myopathy and an amyloid myopathy. Four patients received a corticosteroid-immunoglobulins or cyclosporin regimen. An improvement in the camptocormia was observed in three cases. In the other cases the treatment consisted of chemotherapy on account of severe nephrotic syndrome, a coenzyme-Q treatment for the patient with mitochondrial myopathy and only physiotherapy in the case of congenital myopathy, but without positive effect on camptocormia.

CONCLUSION

Camptocormia appears as a muscular symptom that may reveal an axial myopathy due to multiple and varied pathologies. Thus, the discovery of camptocormia requires an aetiological investigation in order to propose an adequate treatment, which should be associated with physiotherapy.

Computed tomography image analysis of the calcaneus in male osteoporosis

The present study aimed to characterize bone microarchitecture assessed by computed tomography (CT) at the calcaneus in male subjects suffering from osteoporosis. Seventy-nine subjects were assessed (45 with osteoporosis and 34 control subjects matched for age). Osteoporosis was defined according to the World Health Organization classification either at the lumbar spine or at the femoral neck. Thirty-three subjects (73%) had a past history of low-energy fracture mainly represented by vertebral fractures (24/33). Nine axial sections (1 mm in width and 2 mm apart) were selected for each subject. Bone microarchitecture analysis was performed using structural (binary and skeletonized images but also skeletonization from gray levels) and fractal analyses. Bone densitometry by dual-energy X-ray absorptiometry (DXA) at the calcaneus was also performed in 73 cases. Bone mineral density (BMD) was decreased in osteoporotic patients compared with controls both at the lumbar spine and hip and also at the calcaneus (p<0.01). Also 14 microarchitectural features among 25 measured were significantly different between the two groups (p<0.01). The odds ratio for fracture per 1 control group standard deviation decrease were also significant for 13 structural features but also for BMD at the calcaneus. The odds ratios after adjustment for BMD at the calcaneus were significant for the following features (p<0.05): number of valleys, 2.8 (1.2-6.9); trabecular partition, 3.3 (1.3-7.9); apparent trabecular spacing, 1.8 (1.0-3.1); trabecular bone pattern factor, 2.2 (1.1-4.3); Euler number, 3.0 (1.1-8.7); node-to-terminus strut count, 3.3 (1.4-7.8); terminus-to-terminus strut count, 2.9 (1.2-6.9); and fractal dimension, 3.7 (1.5-9.7). Few and weak correlations were found between BMD at the calcaneus measured with DXA and features obtained from CT, suggesting that these two methods give different information about bone status. In conclusion, male osteoporosis is a disease characterized by decreased bone mass but also by microarchitectural deterioration of bone tissue which is partly independent of BMD.

Foramen magnum syndrome secondary to calcium pyrophosphate crystal deposition in the transverse ligament of the atlas

STUDY DESIGN

This report illustrates two rare cases of foramen magnum syndrome caused by a retro-odontoid mass in which calcium pyrophosphate dihydrate crystals were found.

OBJECTIVES

To analyze the preoperative studies and the diagnostic criteria and to discuss the surgical treatment. The present cases will be compared with previous ones described in the literature.

SUMMARY OF BACKGROUND DATA

Deposition of calcium pyrophosphate dihydrate crystals occurs into the fibrous and hyaline cartilage of the joints and intervertebral discs of the spine. Half of the patients known to have a chondrocalcinosis had asymptomatic calcification in the odontoid region. Ten patients were published in the literature as having a spinal cord syndrome secondary to calcium pyrophosphate dihydrate deposition in the odontoid region.

METHODS

In both cases the preoperative studies were analyzed, and the retro-odontoid mass was resected and histologically examined. Both had an anterior transoral approach and have been followed for 1 year.

RESULTS

According to the preoperative radiographs the diagnosis was suspected and confirmed histologically. Transoral approach was done with no need in either case for a posterior stabilization.

CONCLUSIONS

Compression of the spinal cord by calcium pyrophosphate dihydrate deposition may occur. The preoperative diagnosis may be highly suspected after radiographic study and histologically confirmed. Transoral resection is the treatment of choice. Posterior stabilization should be considered only in cases of craniovertebral instability.

Radio-anatomic demonstration of the vertebral lumbar venous plexuses: an MRI experimental study

The aim of this study was to provide a basis of knowledge of the anatomy of the venous plexuses in the lumbar spine both in anatomical slices and in MR images in order to help the analysis of these structures in MR images of living subjects. Four fresh cadaveric lumbar spines were studied after the injection of coloured gelatin mixed with gadolinium. The specimens were injected by an intraosseous technique. Axial and sagittal fat-saturated T1-weighted MR images were performed on the specimens. Thereafter, specimens were frozen and cut into 5-mm thick slices, three in the axial plane and one in the sagittal plane. All the components of the internal and external venous plexuses were identified on the MR images in correlation with the corresponding anatomic sections. The MR anatomy of the venous system of the lumbar spine is important as it has been implicated in many pathophysiological mechanisms and as it may also cause pitfalls in MR imaging.

Thoracic outlet: anatomic correlation with MR imaging

OBJECTIVE

The purpose of this report is to describe the normal MR anatomy of the thoracic outlet and its modification after postural maneuvers using an anatomic-MR imaging correlation.

CONCLUSION

MR imaging appears to be a useful technique to study the thoracic outlet and its contents because of its excellent soft-tissue depiction and its multiplanar capabilities. T1-weighted images obtained in the sagittal plane clearly depicted the different compartments of the cervicothoracic-brachial junction. Hyperabduction maneuvers may have potential applications in the assessment of the thoracic outlet syndrome by showing the location of compression.

Comparison of double-contrast CT arthrography image quality with nonionic contrast agents: isotonic dimeric iodixanol 270 mg I/mL and monomeric iohexol 300 mg I/mL

RATIONALE AND OBJECTIVES

The authors evaluated the image quality on delayed CT arthrography images with the use of the nonionic dimeric contrast agent, iodixanol 270 mg I/mL, compared with iohexol 300 mg I/mL.

METHODS

A total of 132 patients with shoulder pain were included in a randomized, parallel, double-blind study. Sixty seven patients received iodixanol and 65 patients received iohexol. Patients underwent two CT-arthrography examinations: the first was performed 20 to 30 minutes after contrast injection and the second, 50 to 70 minutes after contrast injection. Data from 31 patients were excluded from the efficacy analysis. The overall quality of CT arthrography images was graded into four categories: excellent, good, moderate, and bad.

RESULTS

The overall quality of delayed CT arthrography images was significantly better in the iodixanol group (P = 0.001, alpha = 0.05). On the first CT examination, image quality was good or excellent in 88% of the cases in the iodixanol group and in 96.1% in the iohexol group. The results on the delayed CT arthrography examination indicated that image quality was good or excellent in 88% of the cases when iodixanol was used and in 63.5% when iohexol was used.

CONCLUSIONS

The overall quality of delayed images was significantly better with iodixanol than with iohexol.

MR imaging of the knee at 0.2 and 1.5 T: correlation with surgery

OBJECTIVE

The purpose of this study was to compare the diagnostic efficacy of low- and high-field-strength MR imagers in the diagnosis of anterior cruciate ligament tears and meniscus tears.

SUBJECTS AND METHODS

In 219 patients with suspected internal derangement of the knee, MR imaging at 0.2 and 1.5 T was performed with similar sequences. Only patients with surgically confirmed diagnosis (n = 90) were included in the statistical analysis. Radiologists were unaware of diagnosis and field strength. Sensitivity, specificity, diagnostic accuracy, and inter- and intraobserver variability were determined.

RESULTS

There was excellent correlation between the field strengths in accuracy, sensitivity, and specificity for anterior cruciate ligament and meniscus tears. Accuracy for medial meniscus, lateral meniscus, and anterior cruciate ligament tears was 91-93%, 88-90%, and 93-96%, respectively, at 0.2 T and 91-94%, 91-93%, and 97-98%, respectively, at 1.5 T. Inter- and intraobserver variability values showed excellent correlation (kappa > 0.8).

CONCLUSION

The level of diagnostic accuracy in anterior cruciate ligament tears and meniscus tears is comparable for low- and high-field-strength MR imagers.

[Imaging of synovial lesions, neoplastic or non-neoplastic]

The purpose of this paper is to present the contribution of imaging in the assessment of synovial diseases, especially in the differentiation between infectious synovitis and rheumatoid arthritis, and in the diagnosis of tumoral and pseudotumoral synovial lesions (idiopathic (osteo)chondromatosis, pigmented villonodular synovitis, synovial hemangioma, lipoma arborescens...).

Does high-resolution computed tomography image analysis of the distal radius provide information independent of bone mass?

This study aimed to investigate the usefulness of computed tomography (CT) image analysis of the distal radius for comparing two groups of postmenopausal women matched for age and bone mineral density at both the lumbar spine and femoral neck. The first one consisted of 16 women with at least one vertebral fracture and the second consisted also of 16 women without disease affecting bone mass or bone metabolism. Eight slices were selected in each patient: four consecutive coronal slices and four consecutive axial slices. Bone texture analysis was performed using structural methods leading to the measurement of 24 features. Most of the structural variables derived from histomorphometric parameters and were measured after segmentation from a binary or a skeletonized image. Nine variables were significantly different between the two groups on axial slices: valley number, valley surface area, apparent bone volume/tissue volume (BV/TV), apparent trabecular separation, apparent trabecular number, trabecular bone pattern factor, trabecular skeletal length, node count, and node-to-node strut count. Also four variables were significantly different between osteoporotic women and controls on coronal slices: apparent BV/TV, trabecular partition, node-to-node strut count, and terminus-to-terminus strut count. In conclusion this study suggests that bone texture analysis could yield additional data on bone mass for explaining bone strength and therefore could be used for improving the prediction of fracture risk.

In vivo comparison between computed tomography and magnetic resonance image analysis of the distal radius in the assessment of osteoporosis

In a prospective case-control cross-sectional study, we investigated the usefulness of both computed tomography (CT) and magnetic resonance (MR) image analysis of the distal radius for distinguishing a small sample of fractured osteoporotic women from control women regardless of bone mineral density. The study population included 12 subjects who were divided into two groups according to their bone status. The first group consisted of six women with at least one vertebral fracture occurring in the absence of high-energy trauma, and the second group consisted of six women without disease affecting bone mass or bone metabolism. Cross-sectional and coronal slices were obtained from both CT and MR systems. For CT images, the slice thickness was 1000 jim and the plane resolution was approx 200 jim x 200 jim. MR images were obtained from a 1.5-T imager with a two-dimensional spin-echo Ti-weighted sequence leading to a slice thickness of 2000 jim and a plane resolution of 195 jim x 195 jim. Bone texture analysis was performed using fractal and structural methods leading to the measurement of 23 features. Most of the structural variables derived from histomorphometric parameters and were measured after segmentation from a binary or a skeletonized image. Bone densitometry was measured by dual-energy X-ray absorptiometry both at the lumbar spine and the nondominant femoral neck. On cross-sectional slices, 12 variables, mainly obtained from structural analysis, were significantly different between the two groups for CT images (p < 0.05) against two variables only for MR images (p < 0.05). The number of variables statistically different between the two groups was significantly higher for CT images compared with MR images (p = 0.003). In the same way, odds ratios for fracture per 1 control group standard deviation decrease were significant for 10 variables on CT images, whereas, in contrast, none of the variables measured on MRI images led to significant odds ratios. The results obtained for the two methods on coronal slices were poorer without a difference between either CT or MR images in terms of discrimination between fracture and nonfracture subjects. In conclusion, this study suggests that bone texture analysis obtained from CT compared with MRI offers a best discrimination between controls and osteoporotic patients, probably the result to the spatial resolution. which is better for CT than for MR images.

[Cortical septic osteitis: two cases]

Cortical septic osteitis is defined as a predominant or exclusive infection of the cortex which may lead to diagnosis pitfalls. With the two cases presented here, principal radiological features allowing a correct diagnosis are recalled.

Percutaneous vertebroplasty in the treatment of osteoporotic vertebral compression fractures: an open prospective study

OBJECTIVE

To assess the efficacy and safety of percutaneous vertebroplasty in osteoporotic vertebral compression fractures responsible for severe and persistent pain.

METHODS

Sixteen patients were included in this open prospective study. Inclusion criteria were: one or 2 vertebral fractures responsible for severe pain, i.e., higher than 50 mm on a visual analog scale (VAS: 0-100 mm), scores 3, 4 or 5 according to the McGill-Melzack scoring system, and evolving for more than 3 months. Assessment criteria were the changes over time (Days 3, 30, 90, 180) in VAS and McGill-Melzack scoring system. The changes over time in a generic health status instrument score [the Nottingham Health Profile (NHP)] were also assessed. Statistical comparisons were performed using the Wilcoxon T test.

RESULTS

There were 9 women and 7 men: postmenopausal osteoporosis (n = 7), corticosteroid induced osteoporosis (n = 2), and male osteoporosis (n = 7). Vertebroplasty was performed in 20 vertebrae. A statistically significant decrease of both VAS (-53%, p < 0.0005) and McGill-Melzack scoring system (p < 0.005) was observed at Day 3. The results were also significant at Days 30, 90, and 180 for both scales (p < 0.005 and p < 0.01, respectively). A significant decrease over time for 5/6 dimensions of the NHP score was also noted: pain (p < 0.01), physical mobility (p < 0.05), emotional reactions (p < 0.05), social isolation (p < 0.05), and energy (p < 0.05). We observed no adverse event, and no vertebral fracture has occurred after 6 months of followup.

CONCLUSION

Percutaneous vertebroplasty is a useful and safe procedure for treating persistent painful osteoporotic fractures. Controlled studies with longterm followup are required.

[Imaging of the shoulder]

Except for instability, a variety of causes has been described in the painful shoulder. A thorough clinical examination may help establish the cause of shoulder pain. Even if modern imaging modalities (ultrasonography, computed tomography, MR imaging) allowed a precise diagnostic and therapeutic approach, plain radiographs are still necessary. Performed by an experienced radiologist, ultrasonography may be useful for the assessment of rotator cuff tears which are a common problem. CT arthrography and MR imaging are only recommended in preoperative assessment. In calcific tendinitis plain radiographs provide evidence of calcifications. It is not difficult to establish clinically the diagnosis of adhesive capsulitis and arthrography is the only technique to reveal the articular capacity limitation reliably. In degenerative osteoarthritis of the glenohumeral joint, CT arthrography is necessary to assess the rotator cuff changes and lenoid osseus findings before undergoing shoulder arthroplasty.

Therapeutic percutaneous injections in the treatment of malignant acetabular osteolyses

Percutaneous injection of methylmethacrylate or ethanol may provide marked pain relief or bone strengthening in patients with malignant acetabular osteolyses who are unable to tolerate surgery. Injection of methylmethacrylate is usually indicated when osteolysis involves the weight-bearing part of the acetabulum (ie, the acetabular roof); in all other cases, ethanol injection is preferred. Ethanol and methylmethacrylate injections may be performed together if both weight-bearing and nonweight-bearing parts of the acetabulum are involved or extensive soft-tissue involvement is present. Moreover, these injections may be performed prior to radiation therapy, which complements their action due to similar but delayed effects on pain, or after radiation therapy that failed to relieve pain or in cases of local recurrence. Radiography and computed tomography must be performed prior to therapeutic percutaneous injection to assess the location and extent of the lytic process, the presence of cortical destruction or fracture, and the presence of soft-tissue involvement. Fever and transitory worsening in pain may occur secondary to inflammatory reaction in the hours following injection; however, these side effects usually resolve spontaneously within 1-3 days. The decision to perform therapeutic percutaneous injections should be made by a multidisciplinary team because the choice between this option and alternative methods of treatment depends on several factors including the location of the lesion, the local and general extent of the disease, the pain and functional disability experienced by the patient, and the patient's state of health and life expectancy.

Image analysis of the distal radius trabecular network using computed tomography

Bone texture analysis might provide information about bone structure in a noninvasive manner. In a prospective case-control cross-sectional study we investigated the value of computed tomography (CT) image analysis of the distal radius in the assessment of osteoporosis. Twenty patients suffering from postmenopausal osteoporosis were studied and compared with 21 age-matched controls. Eight slices were selected in each patient: four consecutive coronal slices and four consecutive cross-sectional slices. Bone texture analysis was performed using statistical, fractal and structural methods leading to the measurement of 32 features. Structural variables derived from histomorphometric parameters were measured after segmentation from a binary or a skeletonized image. Bone mineral density was measured by dual-energy X-ray absorptiometry both at the lumbar spine and the femoral neck. Eight of the 9 statistical features were significantly different in osteoporotic women as compared with controls (coronal slices, p < 0. 05). Seven structural variables were statistically different between the two groups on coronal slices (p < 0.05): valley surface area, bone volume/tissue volume, trabecular partition, Euler's number, trabecular bone pattern factor, node-to-node strut count and terminus-to-terminus strut count. The most significant results on coronal slices (p < 0.01) concerned 4 structural features: trabecular partition, Euler's number, trabecular bone pattern factor and terminus-to-terminus strut count. Three features were statistically different (p < 0.01) between the two groups on cross-sectional slices (skeletonization from gray levels). A few features yielded by texture analysis were correlated with both lumbar spine and femoral neck bone mineral density, but the level of these correlations was weak (r < 0.5). In conclusion, CT image analysis of the distal radius is a useful tool for characterizing bone texture alterations in osteoporotic women. These findings are in keeping with microarchitectural osteoporosis-related changes diagnosed on bone biopsies.

The first European family with tibial muscular dystrophy outside the Finnish population

We report the first European tibial muscular dystrophy (TMD) family outside the Finnish population. Clinical examination showed late onset distal leg myopathy similar to the description of TMD. A molecular genetic study was made owing to the very recent TMD linkage findings on chromosome 2q31. All five clinically affected patients segregated a specific haplotype for the locus, whereas two unaffected patients had different haplotype. The results of this family without Finnish ancestors show that TMD exists outside the Finnish population.

[SAPHO syndrome and aseptic osteitis]

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.

[Malignant melanoma of soft tissues. Apropos of a case]

A case of malignant melanoma of the quadriceps tendon is reported. This is an uncommon soft tissue sarcoma of melanocytic origin. The appearance on MRI depends on its melanin content. The microscopic appearance is distinctive and prognosis is poor. This tumor should be kept in mind when a nodular lesion is detected in specific tendon or aponeurosis.

Percutaneous vertebroplasty: state of the art

Vertebroplasty is an effective new radiologic procedure consisting of the percutaneous injection of a biomaterial, usually methyl methacrylate, into a lesion of a vertebral body. This technique allows marked or complete pain relief and bone strengthening in most cases. The principal indications for vertebroplasty are osteolytic metastasis and myeloma, painful or aggressive hemangioma, and osteoporotic vertebral collapse with debilitating pain that persists despite correct medical treatment. Radiography and computed tomography must be performed in the days preceding vertebroplasty to assess the extent of vertebral collapse, the location and extent of the lytic process, the visibility and degree of involvement of the pedicles, the presence of cortical destruction or fracture, and the presence of epidural or foraminal stenosis caused by tumor extension or bone fragment retropulsion. Leakage of methyl methacrylate during vertebroplasty may cause compression of adjacent structures and necessitate emergency decompressive surgery; thus, the procedure should be performed only in a surgical center. The decision to perform vertebroplasty should be made by a multidisciplinary team because the choice between vertebroplasty, surgery, radiation therapy, medical treatment, or a combination thereof depends on a number of factors. Radiologists need to be aware of the various indications for vertebroplasty and of potential future developments and applications of the procedure.

CT scan texture analysis of the distal radius: influence of age and menopausal status

OBJECTIVES

To gain information on bone architecture by performing bone texture analysis in a sample of women covering a broad age range.

PATIENTS AND METHODS

We studied 29 healthy women aged 23 to 80 years (55 +/- 18 years), 19 of whom were postmenopausal. None was taking drugs known to influence bone mass or bone metabolism. Computed tomography of the nondominant distal radius was performed with 1 mm slice thickness and 1 mm gap. Four consecutive coronal and four consecutive axial sections were selected for each patient and entered into a PC-type computer. Bone texture was evaluated using grey level run length analysis (five parameters), differential local variation analysis (four parameters), fractal analysis (two parameters), trabecular network extraction and three-dimensional relief characterization. The mean of each study parameter for the four coronal sections and for the four axial sections was calculated. Absorptiometry was done in 16 patients.

RESULTS

Linear correlations with age were strongest (P < 0.001) for parameters measured on coronal sections by trabecular network extraction, i.e., trabecular bone volume (r = -0.68), trabecular plate separation (r = -0.65), total skeletal length (r = -0.71), number of nodes (r = 0.73), number of node-node segments (r = -0.74) and trabecular bone pattern factor (r = 0.71). Also, these parameters were significantly different between premenopausal women (33 +/- 9 years) and postmenopausal women (67.3 +/- 9 years). Correlations between bone mineral density and texture parameters were few in number and modest in strength, suggesting that the parameters measured may reflect bone structure rather than bone mass.

CONCLUSION

Bone texture in women undergoes changes with advancing age that may reflect alterations in bone microarchitecture.

Acetabular labrum: MRI in asymptomatic volunteers

PURPOSE

The purpose of this study was to describe the MR appearance of the acetabular labrum in asymptomatic hips on high resolution MRI.

METHOD

Fifty-two hips in 46 asymptomatic volunteers with an age range of 15-85 years were evaluated with coronal and axial T1-weighted and T2-weighted sequences. The shape, margin, size, and signal intensity of the acetabular labrum were analyzed.

RESULTS

The labrum was absent in its anterosuperior aspect in five hips (10%). Intralabral regions of intermediate of high signal intensity were detected in 30 hips (58%) imaged with T1-weighted and proton density-weighted sequences. Intralabral linear hyperintense foci reaching the articular surface and consistent with a labral tear were detected in four labra on T2-weighted images. Intralabral microcysts were seen in three labra.

CONCLUSION

The MR appearance of the hip labrum is varied in asymptomatic volunteers. Intralabral increased signal intensity and absent anterosuperior labra are especially frequent and may represent asymptomatic lesions or normal variations.

Percutaneous vertebroplasty in patients with osteolytic metastases or multiple myeloma

Osteolytic metastases and spinal myeloma lesions are difficult to treat because they denote disseminated malignant disease. The pain-relieving and other effects of radiation therapy are delayed. We evaluated short- and medium-term outcomes of vertebroplasty in this indication, in patients with severe or excruciatingly severe pain (McGill-Melsack score 4 or 5) unresponsive to narcotics.

PATIENTS AND METHODS

forty vertebras were treated in 37 patients including 29 with bone metastases and eight with multiple myeloma. Mean age was 58 years (range 36-83). The spinal segment involved was the cervical spine in five cases, the thoracic spine in 12 and the lumbar spine in 23. Vertebroplasty was done under fluoroscopy guidance after premedication and local anesthesia.

RESULTS

thirty-six patients (97.3%) reported a decrease in their pain 48 hours after the procedure; five of these patients (13.5%) were completely free of pain, 20 (55%) were significantly improved and 11 (30%) were moderately improved. One patient failed to respond. The clinical results were not correlated to the extent of vertebral body filling. Beneficial effects were increased or unchanged in 100% of cases after one month, 88.9% after three months and 75% after six months. Leakage of the cement outside the vertebral body occurred in 29 cases (72.5%), usually into the paraspinal soft tissues (n = 21,52.5%). Leakage was usually clinically silent and only two patients developed severe nerve root pain due to leakage into a neural foramen, with in both instances a favorable outcome after surgery.

CONCLUSION

Vertebro- plasty is simple and effective for the treatment of osteolytic metastases and multiple myeloma lesions, but should be performed only in centers with neurosurgical and/or orthopedic surgery units because of the possibility of severe complications.