Bone geometry in response to long-term tennis playing and its relationship with muscle volume: a quantitative magnetic resonance imaging study in tennis players.

The benefit of impact-loading activity for bone strength depends on whether the additional bone mineral content (BMC) accrued at loaded sites is due to an increased bone size, volumetric bone mineral density (vBMD) or both. Using magnetic resonance imaging (MRI) and dual energy X-ray absorptiometry (DXA), the aim of this study was to characterize the geometric changes of the dominant radius in response to long-term tennis playing and to assess the influence of muscle forces on bone tissue by investigating the muscle-bone relationship. Twenty tennis players (10 men and 10 women, mean age: 23.1+/-4.7 years, with 14.3+/-3.4 years of playing) were recruited. The total bone volume, cortical volume, sub-cortical volume and muscle volume were measured at both distal radii by MRI. BMC was assessed by DXA and was divided by the total bone volume to derive vBMD. Grip strength was evaluated with a dynamometer. Significant side-to-side differences (P<0.0001) were found in muscle volume (+9.7%), grip strength (+13.3%), BMC (+13.5%), total bone volume (+10.3%) and sub-cortical volume (+20.6%), but not in cortical volume (+2.6%, ns). The asymmetry in total bone volume explained 75% of the variance in BMC asymmetry (P<0.0001). vBMD was slightly higher on the dominant side (+3.3%, P<0.05). Grip strength and muscle volume correlated with all bone variables (except vBMD) on both sides (r=0.48-0.86, P<0.05-0.0001) but the asymmetries in muscle parameters did not correlate with those in bone parameters. After adjustment for muscle volume or grip strength, BMC was still greater on the dominant side. This study showed that the greater BMC induced by long-term tennis playing at the dominant radius was associated to a marked increase in bone size and a slight improvement in volumetric BMD, thereby improving bone strength. In addition to the muscle contractions, other mechanical stimuli seemed to exert a direct effect on bone tissue, contributing to the specific bone response to tennis playing.

Primary bone oxalosis: the roles of oxalate deposits and renal osteodystrophy.

Primary oxalosis is a rare congenital disorder. The excessive oxalate biosynthesis induces deposits in many organs, particularly in kidney and bone. The late onset of primary oxalosis is reported in a 50-year-old man. His chronic renal failure was treated by maintenance hemodialysis for 3 years. He then developed a diffuse bone disease with osteosclerosis and roentgenographic features of hyperparathyroidism. A parathyroidectomy was performed, with debatable improvement of bone lesions. Laboratory results and histologic and histomorphometric studies before and after parathyroidectomy suggest a double histopathogenetic mechanism for this bone disease: renal osteodystrophy and massive bone oxalate deposits. Such deposits may induce both a heterogeneous osteosclerosis with dense metaphyseal bands and histologic bone lesions similar to those of hyperparathyroidism. The crystalline deposits induce in the bone tissue a granulomatous macrophagic reaction. These macrophages are unable to phagocytize the crystals and may be involved in active bone resorption. Bone lesions of oxalosis occur in patients with chronic renal failure, and hyperparathyroidism has a worsening role.

Costo-vertebral arthropathy. Diagnostic and therapeutic value of arthrography.

The authors report five cases of costo-vertebral (CV) joint arthropathies, without osteo-arthritis. The patients had referred pain, with misleading irradiations to the loin or to the abdomen, so that the diagnosis was difficult. The authors have performed in these five cases an arthrography of T11 and T12 CV joints. In every case, the arthrography triggered pain at one of these levels. The arthrography was followed by intra-articular injection of corticosteroid derivative in the symptomatic joint. In these cases, this procedure was a valuable diagnostic and therapeutic method. CV joint arthropathies are frequent, but often lead to incorrect diagnosis. These preliminary results encourage further use of this procedure in CV arthropathies.

[Portal vein thrombosis and hereditary protein C deficiency. Presentation of a case and review of the literature]. / Thrombose portale et déficit héréditaire en protéine C. Présentation d'un cas et revue de la littérature.

The authors report the case of a 51 year-old man, without any personal or familial history of thromboembolism, presenting with abdominal pain. Portal vein thrombosis was demonstrated by ultrasonography and arteriography. The patient had neither esophageal varices or congestive gastropathy. No cause for portal vein thrombosis was detected. Type I protein C deficiency was demonstrated in this patient as well as in his asymptomatic sister. The presence of a (fortuitously?) associated increase in platelet aggregability initially led to a trial regimen of aspirin (300 mg per day); abdominal pain resolved, and a partial regression of portal vein thrombosis was demonstrated on ultrasonograms six months later; no further complications occurred during the 4-year follow-up period. The 13 previously published cases of protein C deficiency-associated portal vein thrombosis are reviewed.

[Asymptomatic cystic dilatation of the choledochus in an adult]. / Dilatation kystique asymptomatique du cholédoque chez un adulte.

A congenital choledochal cyst, type Ia according to Todani's classification, was discovered fortuitously in a 54-year old man by abdominal sonography. The patient had no biliary symptoms, and liver tests were normal. Excision of the cyst was performed because of the theoretical risk of cholangiocarcinoma. Recovery was uneventful.

[A case of fracture-separation of the cervical spine at the C6 articular level (author's transl)]. / A propos d'un cas de fracture-séparation du massif articulaire du rachis cervical.

A typical case of fracture-separation of the cervical spine at the C6 articular level is described. The authors define the radiological signs of this rare but severe traumatic lesion, and emphasize that it is easy to diagnose this condition if one keeps it in mind.

[Arthropathies of the limbs in dialyzed renal failure patients]. / Arthropathies des membres chez les insuffisants rénaux dialysés.

During the last few years, articular symptoms have been reported in chronic renal failure patients on maintenance haemodialysis. A prospective study of arthropathies of the limbs was conducted in 73 such patients: 20 had experienced periarthritis, 32 had tendinous calcifications (3 or more in 16 cases), 29 had destructive arthropathies (especially of the hands) and 10 had calcium pyrophosphate dihydrate deposition. The periarthritis attacks were associated with the presence of tendinous calcifications. The destructive arthropathies could be due to calcium apatite microcrystal deposition, but the study provided no direct evidence of this mechanism. However, the pattern of erosive lesions, their location and their possible association with tendinous calcifications in the same joint were suggestive of calcium apatite deposition. Calcium pyrophosphate deposition, which affected the oldest patients, did not seem to be due to chronic renal failure treated with dialysis. The most important arthropathies were found in patients who had been haemodialysed for a long time, although the correlation was not statistically significant. The dialysis pattern did not seem to influence the articular disorders. There were more cases of calcification and periarthritis among patients whose phosphocalcium product (in mg) exceeded 6000, but the difference with other patients was not statistically significant. Periarthritis and arthropathies are truly disabling for these patients.

Thoracic and lower cervical spine involvement in a case of rheumatoid arthritis.

The authors report a case of spine involvement in a severe case of rheumatoid arthritis treated with corticosteroids. First, the patient developed acute back pain, related to costovertebral joints arthritis at levels T9-T10. Then, neck pain and cord involvement yielded to diagnosis of cervical interapophyseal joints arthritis; there was a C5-C6 subluxation which necessitated surgical treatment. The conjunction of these two rheumatoid localizations is an uncommon feature. Study by the CT scan is valuable when rheumatoid arthritis of the spine is suspected. Lower cervical spine subluxation, even severe, may be well tolerated. Surgery is necessary when there is medullary involvement.

[Lower costovertebral arthritis in rheumatic pelvispondylitis. Pseudourologic manifestation]. / Arthrites costo-vertébrales inférieures de la pelvispondylite rhumatismale. Révélation pseudo-urologique.

Costo-vertebral and costo-transverse joints are often involved during rheumatoid pelvispondylitis. Their involvement may lead to thoracic ankylosis and decreased respiratory capabilities. These arthritis may also cause intercostal or pseudo-visceral pains. The authors report three cases of lower costo-vertebral arthritis, revealed by pseudo-urological, acute or subacute pains. The diagnosis was made on clinical findings (especially mobilization of the lower ribs) and confirmed by X-Rays (especially tomodensitometry). One of the cases presents an image of unilateral pedicle opacity secondary to costovertebral arthritis. The pseudo-urological manifestation of the pain is likely explained by the anatomical relationship between costo-vertebral joints and the sympathetic communicating rami. This close anatomical relationship was confirmed by dissection. Through the communicating rami, the costo-vertebral joints are thus in relation with the sympathetic system, which is responsible for the sensory innervation of the renal space. The pseudo-urological revelation of this arthritis should be compared to that of costal sprains.

Anisotropy measurements obtained by fractal analysis of trabecular bone at the calcaneus and radius.

The resistance of bone tissue is influenced not only by bone density parameters but also by bone architecture parameters, such as the microarchitecture and anisotropy of trabecular bone. We have developed and validated a fractal analysis method for studying bone microarchitecture on roentgenograms. This technique provides reproducible measurements of the fractal dimension (D) of bone, which reflects bone texture. The fractal dimension is determined in 36 different directions; the mean of these 36 values is representative of the image. A polar diagram gives the value of D according to the angle of analysis. By decomposing this diagram using polar Fourier Transform analysis, the parameters related to the shape of the polar diagram can be determined. This diagram image analysis technique has been used for other similar diagrams and applied to the results of our fractal analysis method. Diagram shape characterization may provide information on the angular distribution of results and therefore on the anisotropy of the images under study. The purpose of this study was to compare roentgenograms of the calcaneus and radius in the same subjects to determine whether texture and anisotropy parameters discriminated between these two bones. Roentgenograms of the calcaneus and radius were obtained in ten nonosteoporotic subjects. The radius had a smaller fractal dimension than the calcaneus (mean +/- standard deviation: 1.215 +/- 0.025 and 1.285 +/- 0.066, respectively; p = 0.014). Differences in the shape of the polar diagram were found between the two bones. The mean Fourier coefficient ratio C2/C4 was considerably smaller at the calcaneus (0.63 +/- 0.50) than at the radius (4.88 +/- 3.45; p = 0.005). Our method allows quantitative characterization of texture and anisotropy differences between the calcaneus and radius. The smaller fractal dimension of the radius probably reflects the simpler architecture of this non weight-bearing bone. The differences in polar diagram shape allow to evaluate anisotropy differences between the calcaneus and radius.