L’embrochage centromédullaire antérograde dans les fractures des métatarsiens moyens

Introduction

Despite being common, there are very few articles about metatarsal fractures either concerning surgical techniques or clinical results. This type of fracture may need surgical correction when displaced, especially at an angle. The authors are reporting on the surgical technique and the clinical results of closed anterograde intramedullary pinning of fractures of the neck, diaphysis and the head of the metatarsals.

Equipment and methods

Thirty-one patients with a metatarsal fracture from January 2009 to June 2012 were reviewed retrospectively by the authors. The study included 24 males and 7 females and comprised of 41 fractures of either the diaphysis, the neck or the head of the metatarsal. The technique is described, whereby the pin was introduced from front to back via a small dorsal incision at the base of the metatarsals. The consolidation, the range of movement of the metatarsal phalangeal joint and residual pain were assessed at 6 weeks post surgery and at the final follow-up appointment. The American Orthopaedic Foot and Ankle Society (AOFAS) score was assessed at the last follow-up consultation.

Results

Consolidation was achieved on average after 7.3 weeks (ranging from 6 to 10 weeks). Two patients presented with a moderate limitation to the metatarsal phalangeal joint at 6 weeks, however they had recovered full mobility at the last follow-up appointment. The AOFAS score was 94.7 points (range: 81 to 99).

Conclusion

Due to this simple, reliable and minimally invasive technique, all patients were immediately able to start moving their joint, with partial weight bearing with the help of a rigid boot cast. The overall result is satisfactory and there are very few complications.     

Microarchitecture et résistance mécanique osseuse

Although bone mass is the main determinant of bone mechanical resistance, it explains only 30% to 40% of the variability of this characteristic, indicating that other factors are involved. Among these factors is bone tissue quality, which depends on bone mineralization, bone turnover, and bone microarchitecture. Several parameters for characterizing bone microarchitecture have been developed over the last 15 years. The simplest (Parfitt’s parameters) are trabecular count, width, and separation. A binary image (two levels of gray) of bone tissue can be expanded and used to determine the trabecular bone pattern factor. This method tends to overestimate the number of convex surfaces, which are characteristic of trabecular network disruption. The binary image can be further simplified (skeletonized) and used to count the number of nodes (anastomoses between trabeculae) or free ends (segments disconnected from the network). The bone marrow star volume, the marrow interconnectivity index, and the Euler-Poincaré number are useful for characterizing the bone marrow. These parameters can be measured on bone specimens or on computed tomography (CT) or magnetic resonance imaging (MRI) scans, although in-plane resolution is far lower with scans than with specimens. Two-dimensional analysis is widely used, although three-dimensional studies are more satisfactory. Finally, fractal analysis is an original approach in which fractal dimension measurement, which is fairly simple, is used to determine the degree of network disruption. Ex vivo histomorphometric data suggest that microarchitecture-related factors may explain 10% to 30% of the variability in bone mechanical resistance beyond the proportion explained by bone mass. Similar results have been obtained in microimaging, CT, and MRI studies. Discrepancies across studies exist, however, in the strength of the relationship between bone mass and bone mechanical resistance; they are probably ascribable to differences in measurement sites and to errors in the measurement of variables characterizing bone mechanical resistance. The finite element method may be a means of sidestepping these problems. It can be used, in particular, to calculate Young’s modulus of elasticity from three-dimensional bone segment reconstructions. The results of the few studies of the finite element method are promising but require confirmation. Finally, a more clinical approach consists in comparing bone architecture in patients with osteoporotic fractures and in controls matched on bone mass. A few cross-sectional studies have used this approach. Bone architecture was evaluated using histomorphometry, CT, or MRI. The results indicate that trabecular network disruption is more severe in patients with than without fractures.     

L’ischémie mésentérique chronique

Chronic mesenteric ischemia concerns patients with obliterant arteriopathy of digestive arteries. Clinical presentation is typical but often unrecognized, so-called mesenteric angor, which is associated with chronic abdominal post prandial pain, alimentary fear, and malnutrition. The evolution of this syndrome is progressive and can lead to fatal acute mesenteric ischemia. Diagnosis of chronic mesenteric ischemia is possible only if two of the three digestive arteries are involved. Because of the lack of digestive abnormalities in the earlier stage of this disease, diagnosis is difficult. The aims of the treatment are to treat symptoms to prevent acute mesenteric ischemia. Two therapeutical options are offered to physicians, surgical or endovascular revascularization.     

L’ischémie mésentérique aiguë

Mesenteric ischemia is defined by the anatomical and clinical consequences of a prolonged decrease of splanchnomesenteric perfusion. Mesenteric ischemia is classified not only by following its acute or chronic course, but also by an occlusive or non-occlusive mechanism, and by arterial or veinous vascular involvement. Etiologies of arterial ischemia are emboli from valvulopathy or cardiopathy and thrombosis from pathological arteries. Non occlusive arterial mesenteric ischemia occurs in low-flow states or in patients with vasoconstrictive medications or drugs (cocaine).     

Traitement médicamenteux de la lésion médullaire traumatique au stade aigu

ObjectivesTo evaluate the effect on neurologic outcome and the safety of nimodipine (N), methylprednisolone (M), or both (MN) versus no medical treatment (P) in spinal cord injury at the acute phase.Study designProspective, randomized clinical trial.PatientsOne hundred and six patients with a spinal trauma, including 48 with paraplegia and 58 with tetraplegia.MethodAfter eligibility, patients were randomly allocated in one of the following groups: M = methylpredisolone 30 mg·kg⁻¹ over 1 hour, followed by 5.4 mg·kg⁻¹·h⁻¹ for 23 hours, N = nimodipine 0.015 mg·kg⁻¹·h⁻¹ over 2 hours followed by 0.03 mg·kg⁻¹·h⁻¹ for 7 days, MN or P. Neurologic assessment (ASIA score) was performed by a senior neurologist before treatment and at the 1-year follow-up. Early spinal decompression and stabilization was performed as soon as possible after injury.ResultsOne hundred patients were reassessed at the 1-year follow-up. Neurologic improvement was seen in each group (P < 0.0001), however no neurologic benefit from treatment was observed. Infectious complications occurred more often in patients treated with M. Early surgery (49 patients), within the first 8 hours did not influence the neurologic outcome. The only predictor of the latter was the extent of the spinal injury (complete or incomplete lesion).ConclusionCurrently, no evidence of the benefit of medical treatment in this indication is existing. Because of the lack of clinical studies proving efficacy of pharmacological treatment in this specific pathology, a systematic use of medications cannot be recommended.     

Néphrotoxicité médicamenteuse

Drug-induced nephrotoxicity (DIN) remains a current problem with economic and medical consequences. It affects all nephron segments. Recovery of renal function is based on the identification of risk factors, early diagnosis of renal disease, rapid (if possible) cessation of the causative agent and, in some cases, adjunctive therapy. Prevention is based on identification of early markers of DIN, correction of risk factors, initial assessment of renal function for adequate dosage adjustment and exclusion of other nephrotoxic factors. It has recently been proposed to standardize the phenotype of iatrogenic renal disease and, on the other hand, new markers of renal toxicity allowing early diagnosis and therefore better management of nephrotoxicity.     

Le périoste vascularisé et la reconstruction osseuse

The osteogenic potential of periosteum is widely recognized. During development, it plays a prominent role in the radial growth of long bones. Similarly, it has a key role in the consolidation of fractures. The physiological function of periosteum in the healthy, mature skeleton remains relatively subtle; however, its detachment from the bone surface reactivates its potential for fibrogenic and osteochondrogenic regeneration. This discreet anatomical structure is actually a reservoir of mesenchymal progenitor cells capable of proliferating and differentiating, by reinitializing cellular and molecular cascades of embryogenesis in mesenchymal tissues. However, given the hitherto limited knowledge of the quantitative potential of periosteum and of the pathways regulating tissue differentiation during regeneration, human applications have remained anecdotal. The findings of several in vivo and in vitro experiments indicate that the maintenance of the periosteum's vascularization stimulates its quantitative potential. The structural organization of the regenerated material in vivo is governed by locoregional biological and mechanical regulatory mechanisms that serve to make it capable of performing its new functions. The increasing awareness of periosteum's potential is stimulating active research in the fields of cellular biology and tissue engineering. The demonstration of its regenerative potential in animals gives reason to believe that strips of vascularized periosteum could become part of the developing armamentarium of regenerative medicine.     

L’adénome métanéphrique bilatéral du rein

Renal metanephric adenoma is an uncommon benign epithelial neoplasm. The diagnosis is exclusively histological. Differential diagnosis essentially includes Wilms’ tumor and papillary renal cell carcinoma. Cytogenetic analysis seems to be important for distinguishing these three histological entities. Bilateral metanephric adenoma of the kidney is an exceptional entity (to our knowledge only one case has been reported in the literature) which renders the differential diagnosis with bilateral cancer of the kidney difficult. We report a new case seen in a 64-year-old patient.