Ankle joint pressure changes in high tibial and distal femoral osteotomies: a cadaver study.

AIMS: To assess the effect of high tibial and distal femoral osteotomies (HTO and DFO) on the pressure characteristics of the ankle joint. MATERIALS AND METHODS: Varus and valgus malalignment of the knee was simulated in human cadaver full-length legs. Testing included four measurements: baseline malalignment, 5° and 10° re-aligning osteotomy, and control baseline malalignment. For HTO, testing was rerun with the subtalar joint fixed. In order to represent half body weight, a 300 N force was applied onto the femoral head. Intra-articular sensors captured ankle pressure. RESULTS: In the absence of restriction of subtalar movement, insignificant migration of the centre of force and changes of maximal pressure were seen at the ankle joint. With restricted subtalar motion, more significant lateralisation of the centre of force were seen with the subtalar joint in varus than in valgus position. Changes in maximum pressure were again not significant. CONCLUSION: The re-alignment of coronal plane knee deformities by HTO and DFO altered ankle pressure characteristics. When the subtalar joint was fixed in the varus position, migration of centre of force after HTO was more significant than when the subtalar joint was fixed in valgus. Cite this article: Bone Joint J 2017;99-B:59-65.

[Arthrodesis and endoprostheses of the ankle joint: indications, techniques and pitfalls]. / Arthrodese und Endoprothese des oberen Sprunggelenks: Indikationen, Techniken und Fallstricke.

If adequate conservative measures for the treatment of end-stage ankle osteoarthritis have failed, surgery may be taken into consideration. After exorbitant failure rates in the beginning of total ankle replacement, nowadays this kind of treatment has regained lot of interest and has become a viable alternative to ankle fusion. The correct indication and a precise explanation of the surgical procedure, outcomes and potential complications provide a solid base for future success.Currently, there is no doubt that total ankle replacement has become an important player in the treatment of symptomatic and debilitating end-stage ankle arthritis. With increasing number of patients who undergo total ankle replacement the experience with this kind of procedure increases too. As a consequence several surgeons have started to stretch indications favoring total ankle replacement. However, it must be mentioned here, despite progress in terms of improved anatomical and biomechanical understanding of the hindfoot and improved surgical techniques and instruments, total ankle replacement and ankle fusion remain challenging and difficult procedures. We provide a review article including an overview of the relevant techniques. This article should serve as rough guide for surgeons and help in decision-making regarding total ankle replacement and ankle fusion.

Intraoperative imaging of the distal radioulnar joint using a modified skyline view.

PURPOSE: Nonanatomic reduction of the sigmoid notch in distal radius fractures may lead to limited motion, instability, or pain with pronation and supination. Standard radiological projections only poorly capture the sigmoid notch contours in the axial plane. The purpose of this study was to find an intraoperatively feasible radiological projection that will facilitate an axial view of the distal radioulnar joint. METHODS: We modified a previously described radiographic projection termed the skyline view for evaluating the distal radius axially. We created intra-articular steps at the sigmoid notch in solid foam forearm models to identify the best of 12 projections using an image intensifier. Four observers scored each projection based on the clarity of the sigmoid notch contour and indicated the presence and location of an intra-articular stepoff. RESULTS: The sigmoid notch was best visualized in the modified skyline view with the wrist in extension and 10° to 15° of dorsal forearm angulation relative to the x-ray path. All observers correctly recognized the presence and location of intra-articular steps at the sigmoid notch with this view. The same forearm angulation with the wrist in flexion did not reach equally good visibility of the sigmoid notch. Arm position (wrist flexion, forearm rotation, or forearm angulation) and intra-articular stepoff (none, palmar, or dorsal) were dependent determinates. Elimination of the variable forearm rotation had minimal effect, indicating that forearm rotation is not important for visualization of the sigmoid notch. CONCLUSIONS: The modified skyline view for visualization of the distal radioulnar joint in an axial plane allows good visibility of the sigmoid notch and reliable identification of stepoffs. Further cadaver and in vivo studies are required to verify the validity of this method.

Treatment of ankle osteoarthritis: arthrodesis versus total ankle replacement.

While ankle arthrodesis has remained the gold standard treatment for symptomatic primary, secondary, and posttraumatic ankle arthritis, more recently, total ankle replacement (TAR) has seen considerable improvement in terms of biomechanics, function, and complication rates. However, while in the long-term degeneration of the adjacent joints is almost always found on radiographs after ankle arthrodesis, the longevity of TAR is still insufficient and does not match that of total knee and hip joints. The current review article focuses on the treatment of ankle arthritis by means of arthrodesis and TAR.

Jejunal brush border microvillous alterations in Giardia muris-infected mice: role of T lymphocytes and interleukin-6.

Intestinal colonization with the protozoan Giardia causes diffuse brush border microvillous alterations and disaccharidase deficiencies, which in turn are responsible for intestinal malabsorption and maldigestion. The role of T cells and/or cytokines in the pathogenesis of Giardia-induced microvillous injury remains unclear. The aim of this study was to assess the role of T cells and interleukin-6 (IL-6) in the brush border pathophysiology of acute murine giardiasis in vivo. Athymic nude (nu(-)/nu(-)) CD-1 mice and isogenic immunocompetent (nu(+)/nu(+)) CD-1 mice (4 weeks old) received an axenic Giardia muris trophozoite inoculum or vehicle (control) via orogastric gavage. Weight gain and food intake were assessed daily. On day 6, segments of jejunum were assessed for parasite load, brush border ultrastructure, IL-6 content, maltase and sucrase activities, villus-crypt architecture, and intraepithelial lymphocyte (IEL) infiltration. Despite similar parasitic loads on day 6, infected immunocompetent animals, but not infected nude mice, showed a diffuse loss of brush border microvillous surface area, which was correlated with a significant reduction in maltase and sucrase activities and a decrease in jejunal IL-6 concentration. In both athymic control and infected mice, jejunal brush border surface area and disaccharidases were high, but levels of tissue IL-6 were low and comparable to the concentration measured in immunocompetent infected animals. In both immunocompetent and nude mice, infection caused a small but significant increase in the numbers of IELs. These findings suggest that the enterocyte brush border injury and malfunction seen in giardiasis is, at least in part, mediated by thymus-derived T lymphocytes and that suppressed jejunal IL-6 does not necessarily accompany microvillous shortening.