Proximal femoral reconstruction with modular megaprostheses in non-oncological patients.

INTRODUCTION: Multiple revision hip arthroplasties and critical trauma might cause severe bone loss that requires proximal femoral replacement (PFR). The aim of this retrospective study was to analyse complication- and revision-free survivals of patients who received modular megaprostheses in an attempt to reconstruct massive non-neoplastic bone defects of the proximal femur. Questions/purposes (1) What were general complication rates and revision-free survivals following PFR? (2) What is the incidence of complication specific survivals? (3) What were risk factors leading to a diminished PFR survival? MATERIALS AND METHODS: Twenty-eight patients with sufficient follow-up after receiving a modular proximal femoral megaprosthesis were identified. The indications for PFR included prosthetic joint infection (PJI), periprosthetic fracture, aseptic loosening, non-union and critical femoral fracture. Complications were grouped according to the ISOLS-classification of segmental endoprosthetic failure by Henderson et al. RESULTS: Overall, the complication-free survival was 64.3% at one year, 43.2% at five years and 38.4% at ten years, with 16 patients (57%) suffering at least one complication. Complications were dislocation in eight patients (29%), PJI in 6 patients (21%), periprosthetic fracture in five patients (18%), and aseptic loosening in six patients (21%). Prosthesis stem cementation showed a lower risk for revision in a cox proportional hazard model (95% CI 0.04-0.93, HR 0.2, p = 0.04). CONCLUSION: PFR with modular megaprostheses represents a viable last resort treatment with high complication rates for patients with severe proximal femoral bone loss due to failed arthroplasty or critical fractures. In revision arthroplasty settings, PFR cementation should be advocated in cases of impaired bone quality.

Histone citrullination as a novel biomarker and target to inhibit progression of abdominal aortic aneurysms.

Neutrophil extracellular traps (NETs) have been implicated in the pathogenesis of abdominal aortic aneurysms (AAAs). This study has addressed the notion that NET components might serve as AAA biomarkers or novel targets of AAA therapy. Thus, parameters of neutrophil activation and NET formation were measured in plasma. Their diagnostic marker value was explored in 41 AAA patients and 38 healthy controls. The NET parameter citrullinated histone H3 (citH3) was then validated in 63 AAA patients and 63 controls matched for cardiovascular disease. The prognostic marker potential was investigated in 54 observation periods of AAA growth over 6 months. NETs were further assessed in conditioned medium and sections of aortic tissue. CitH3 was found to be increased in blood (median 362 vs 304 ng/mL, P = 0.004) and aortic tissue (50 vs 1.5 ng/mg, P < 0.001) of AAA patients compared to healthy controls and accumulated in the intraluminal thrombus (629 ng/mg). The diagnostic potential of citH3 ranged at 0.705 area under the ROC curve (AUROC) and was validated with the independent sample set. Furthermore, plasma citH3 predicted AAA growth over the next 6 months (AUROC: 0.707, P = 0.015) and dropped significantly after surgical aneurysm repair. In an angiotensin II - based mouse model of experimental AAA, an inhibitor of histone citrullination was applied to block NET formation and AAA progression. Of note, further growth of an established aneurysm was prevented in mice treated with the NET inhibitor (P = 0.040). In conclusion, histone citrullination represents a promising AAA biomarker and potential therapeutic target to control disease progression.

Sport and Physical Activity Following Primary Total Knee Arthroplasty: A Systematic Review and Meta-Analysis.

BACKGROUND: This systematic review and meta-analysis aims to analyze the sport habits of patients before and after primary total knee arthroplasty (TKA) by answering the following questions: (1) Is there a postoperative improvement of sport activity based on validated activity scores? (2) Does age influence the postoperative improvement of sport activity based on validated activity scores? (3) What are the preoperative and postoperative sport participation rates and the return to sport rates (RTS)? (4) What are the sport disciplines and sport patterns? METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, MEDLINE and Scopus were searched for studies reporting the physical activity level and sport habits of patients before and after primary TKA based on validated activity scores or an activity questionnaire. Random effect models were implemented to pool the mean differences (MDs) of activity score values and the difference between preoperative and postoperative sport participation rates. RESULTS: Twenty-five studies were included reporting on 6035 TKAs. Physical activity levels improved significantly according to the University of California, Los Angeles (UCLA) activity score (MD 1.55, 95% confidence interval [CI] 0.35-2.76, n = 1239, I2 = 99%, P < .01) and the Tegner score (MD 1.14, 95% CI -0.48 to 2.76, n = 483, I2 = 93%, P < .01). Younger patients (≤55 years) had the highest improvement in the UCLA activity scores following primary TKA (MD 3.12, 95% CI -1.79 to 8.04, n = 67, I2 = 96%, P < .01). Sport participation decreased slightly but not significantly (incidence rate difference -8%, 95% CI -0.14 to -0.2, n = 2673 patients, I2 = 38%, P = .09). The median RTS was 71.2%. Patients predominantly engaged in low-impact sports, especially walking, cycling, and swimming. CONCLUSION: According to validated activity scores, the level of physical activity significantly increases following primary TKA. Young patients (≤55 years) had the highest gain in physical activity according to the UCLA activity score following primary TKA. Sport participation shows a slight but nonsignificant decrease; intermediate and high-impact sports were abandoned to a large degree while participation rates for low-impact sports predominantly increased. RTS varied, although approximately 70% resume sport activities. LEVEL OF EVIDENCE: IV (review including case series).

A Novel Diagnostic and Prognostic Score for Abdominal Aortic Aneurysms Based on D-Dimer and a Comprehensive Analysis of Myeloid Cell Parameters.

The pathogenesis of abdominal aortic aneurysm (AAA) involves a central component of chronic inflammation which is predominantly mediated by myeloid cells. We hypothesized that the local inflammatory activity may be reflected in systemic alterations of neutrophil and monocyte populations as well as in soluble factors of myeloid cell activation and recruitment. To establish their marker potential, neutrophil and monocyte sub-sets were measured by flow cytometry in peripheral blood samples of 41 AAA patients and 38 healthy controls matched for age, sex, body mass index and smoking habit. Comparably, circulating factors reflecting neutrophil and monocyte activation and recruitment were assayed in plasma. Significantly elevated levels of CD16+ monocytes, activated neutrophils and newly released neutrophils were recorded for AAA patients compared with controls. In line, the monocyte chemoattractant C-C chemokine ligand 2 and myeloperoxidase were significantly increased in patients' plasma. The diagnostic value was highest for myeloperoxidase, a mediator which is released by activated neutrophils as well as CD16+ monocytes. Multivariable regression models using myeloid activation markers and routine laboratory parameters identified myeloperoxidase and D-dimer as strong independent correlates of AAA. These two biomarkers were combined to yield a diagnostic score which was subsequently challenged for confounders and confirmed in a validation cohort matched for cardiovascular disease. Importantly, the score was also found suited to predict rapid disease progression. In conclusion, D-dimer and myeloperoxidase represent two sensitive biomarkers of AAA which reflect distinct hallmarks (thrombus formation and inflammation) of the pathomechanism and, when combined, may serve as diagnostic and prognostic AAA score warranting further evaluation.