Two-year radiologic assessment of the Pinnacle cup-a migration analysis with EBRA.

INTRODUCTION: The most common cause of failure in total hip arthroplasty (THA) is aseptic loosening. Uncemented cup migration analysis by EBRA (Einzel-Bild-Roentgen-Analyse) has shown to be a good predictive indicator for early implant failure if the cup migrates more than 1 milimeter (mm) within the first 2 years after surgery. In this study, we investigated the migration behaviour of an uncemented press-fit cup after 2 years follow-up. MATERIALS AND METHODS: Applying a retrospective study design, we reviewed all consecutive patients who received an uncemented press-fit cup at our Department between 2013 and 2018. A total of 484 patients were identified. We reviewed medical histories and performed radiological measurements using EBRA-Cup software. EBRA measurements and statistical investigations were performed by two independent investigators. RESULTS: A total of 165 cups in 159 patients (female: 90; male: 69) met our inclusion criteria. Mean age at surgery was 66.7 (range 18.4-90.5) years. EBRA migration analysis showed a mean total migration of 0.7 mm (range 0.0-6.3) over our follow-up period of 2 years. Of the investigated cups, 53.2% showed less than 1 mm migration in the investigated follow-up period. CONCLUSION: In conclusion, the Pinnacle cup used in our study provides low mean migration at final follow-up. Based on the assumption of secondary stabilization, good long-term outcome of the Pinnacle cup can be expected. TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION: Number: 20181024-1875; Date: 2018-09-20.

[Trochleoplasty: Surgical technique : Video article]. / Trochleaplastik: Operationstechnik : Videobeitrag.

A 29-year-old physically active patient presented with recurrent right-sided patellar dislocation. Clinical and radiological investigation showed patellar instability with stable cruciate and collateral ligaments, excess internal rotation of the right femur, as well as trochlear dysplasia. Treatment consisted of trochleoplasty in combination with medial patellofemoral ligament reconstruction.

"Inflamm-aging" influences immune cell survival factors in human bone marrow.

The bone marrow (BM) plays a key role in the long-term maintenance of immunological memory. However, the impact of aging on the production of survival factors for effector/memory T cells and plasma cells in the human BM has not been studied. We now show that the expression of molecules involved in the maintenance of immunological memory in the human BM changes with age. While IL-15, which protects potentially harmful CD8+ CD28- senescent T cells, increases, IL-7 decreases. IL-6, which may synergize with IL-15, is also overexpressed. In contrast, a proliferation-inducing ligand, a plasma cell survival factor, is reduced. IFN-y, TNF, and ROS accumulate in the BM in old age. IL-15 and IL-6 expression are stimulated by IFN-y and correlate with ROS levels in BM mononuclear cells. Both cytokines are reduced by incubation with the ROS scavengers N-acetylcysteine and vitamin C. IL-15 and IL-6 are also overexpressed in the BM of superoxide dismutase 1 knockout mice compared to their WT counterparts. In summary, our results demonstrate the role of inflammation and oxidative stress in age-related changes of immune cell survival factors in the BM, suggesting that antioxidants may be beneficial in counteracting immunosenescence by improving immunological memory in old age.

Plasma cell numbers decrease in bone marrow of old patients.

The BM is well understood to play a key role in plasma cell homing and survival in mice. In humans, BM plasma cells and their functions are less well characterized. In this study, we used paired bone biopsies from the femur shaft and blood samples from persons of different ages to analyze age-related changes of plasma and memory B cells. Our results demonstrated that plasma cells were mainly located in the BM, while a higher percentage of memory B cells was in the peripheral blood than in the BM. The frequency of plasma and memory B cells from both sources decreased with age, while immature and naïve B cells were unaffected. An age-related decline of tetanus- and diphtheria-specific BM plasma cells was observed, whereas influenza A- and cytomegalovirus-specific BM plasma cells were not affected. With the exception of cytomegalovirus, peripheral antibody concentrations correlated with BM plasma cells of the same specificity, but were independent of antigen-specific peripheral blood memory B cells. Our results demonstrate that the BM houses decreased numbers of plasma cells in old age. The number of cells of certain specificity may reflect the number and time point of previous antigen encounters and intrinsic age-related changes in the BM.

Bone marrow T cells from the femur are similar to iliac crest derived cells in old age and represent a useful tool for studying the aged immune system.

BACKGROUND: CD4+ and CD8+ T cells reside in the human bone marrow (BM) and show a heightened activation state. However, only small sample sizes are available from sources such as the iliac crest. Larger samples can be obtained from the femur in the course of hip replacement surgery. It was therefore the goal of the present study to compare the phenotype and function of BM T cells from different sources from elderly persons and to investigate how femur derived bone marrow T cells can serve as a tool to gain a better understanding of the role of adaptive immune cells in the BM in old age. RESULTS: Bone marrow mononuclear cells (BMMC) were isolated from either the iliac crest or the femur shaft. As expected the yield of mononuclear cells was higher from femur than from iliac crest samples. There were no phenotypic differences between BMMC from the two sources. Compared to PBMC, both BM sample types contained fewer naïve and more antigen experienced CD4+ as well as CD8+ T cells, which, in contrast to peripheral cells, expressed CD69. Cytokine production was also similar in T cells from both BM types. Larger sample sizes allowed the generation of T cell lines from femur derived bone marrow using non-specific as well as specific stimulation. The phenotype of T cell lines generated by stimulation with OKT-3 and IL-2 for two weeks was very similar to the one of ex vivo BM derived T cells. Such lines can be used for studies on the interaction of different types of BM cells as shown by co-culture experiments with BM derived stromal cells. Using CMVNLV specific T cell lines we additionally demonstrated that BM samples from the femur are suitable for the generation of antigen specific T cell lines, which can be used in studies on the clonal composition of antigen specific BM T cells. CONCLUSION: In conclusion, our results demonstrate that BMMC from the femur shaft are a useful tool for studies on the role of T cells in the BM in old age.

High recurrence after calf lengthening with the Ilizarov apparatus for treatment of spastic equinus foot deformity.

Both gastrocnemius recession and Achilles tendon lengthening lead to scarring in the calf and have high reported recurrence rates when performed under the age of 8 years. Triceps surae lengthening by external fixation seemed to be a valuable alternative. Twelve calf lengthenings have been performed with an Ilizarov device with a mean correction of 27 degrees. No calcaneal gait was observed, but there was a slow continuous loss of dorsiflexion over the observation period. The Ilizarov technique has a higher recurrence rate than most operative procedures for calf lengthening, but carries virtually no risk in producing calcaneus. The technique cannot be recommended for routine clinical use and may only be an alternative for selected cases.