Hidden blood loss in direct anterior total hip arthroplasty: a prospective, double blind, randomized controlled trial on topical versus intravenous tranexamic acid.

BACKGROUND: Despite a plethora of literature reporting on the use of tranexamic acid (TXA) in total hip arthroplasty (THA), little is available on its effect on post-operative hidden blood loss and even less on its use in the direct anterior approach (DAA), which is gaining popularity. MATERIALS AND METHODS: This study was designed as a prospective, double blind, single centre, randomized controlled trial. Sixty patients were allocated to intravenous administration of 1.5 g of TXA just before wound closure while 60 patients were allocated to topical application of 3.0 g of TXA via a subfascial drain at the end of the procedure. Post-operative blood loss was (1) calculated via a well-established formula based on pre- and post-operative Hb levels, patients characteristics and intra-operative blood loss and (2) measured via the amount that collected in the subfascial drain over time. RESULTS: No statistical significant difference in post-operative blood loss was found, neither when the formula was used (0.55 L [topical] vs 0.67 L [IV]; p = .140) nor when looking at the drain output (0.25 L [topical] vs 0.29 L [IV]; p = .108). No significant difference in secondary outcome measures, such as transfusion of units of packed red blood cells, length of hospital stay or the occurrence of venous thromboembolisms, could be found either. CONCLUSIONS: This study provides detailed insights into the intra- and post-operative blood loss in DAA THA and shows that topical and IV TXA have similar effects on hidden blood loss. Clinical Trial Number: NCT01940692. LEVEL OF EVIDENCE I: Level I-Randomized Controlled Trial.

Diagnosis of prosthetic joint infection with alpha-defensin using a lateral flow device: a multicentre study.

AIMS: The purpose of this current multicentre study is to analyse the presence of alpha-defensin proteins in synovial fluid using the Synovasure lateral flow device and to determine its diagnostic reliability and accuracy compared with the prosthetic joint infection (PJI) criteria produced by the Musculoskeletal Infection Society (MSIS). PATIENTS AND METHODS: A cohort of 121 patients comprising 85 total knee arthroplasties and 36 total hip arthroplasties was prospectively evaluated between May 2015 and June 2016 in three different orthopaedic centres. The tests were performed on patients with a chronically painful prosthesis undergoing a joint aspiration in a diagnostic pathway or during revision surgery. RESULTS: Based on the MSIS criteria, 34 patients (28%) would have had a PJI, and 87 patients had no PJI. Testing with the lateral flow device had a sensitivity of 97.1% (95% confidence intervals (CI) 84.5 to 99.9) and a specificity of 96.6% (95% CI 90.3 to 99.2). The positive predictive value was 91.7% (95% CI 77.7% to 98.3), and the negative predictive value was 98.8% (95% CI 93.6 to 99.9). Receiver operator characteristics analysis demonstrated an area under the curve for the Synovasure test of 0.97 (95% CI 0.93 to 1.00). CONCLUSION: Our findings suggest that the Synovasure test has an excellent diagnostic performance to confirm or reject the diagnosis of a PJI. The results are promising for the care of the painful or problematic knee and hip joint arthroplasty and the test should be considered as part of the diagnostic toolbox for PJIs. Cite this article: Bone Joint J 2017;99-B:1176-82.

Paracrine Maturation and Migration of SH-SY5Y Cells by Dental Pulp Stem Cells.

Neurological disorders are characterized by neurodegeneration and/or loss of neuronal function, which cannot be adequately repaired by the host. Therefore, there is need for novel treatment options such as cell-based therapies that aim to salvage or reconstitute the lost tissue or that stimulate host repair. The present study aimed to evaluate the paracrine effects of human dental pulp stem cells (hDPSCs) on the migration and neural maturation of human SH-SY5Y neuroblastoma cells. The hDPSC secretome had a significant chemoattractive effect on SH-SY5Y cells as shown by a transwell assay. To evaluate neural maturation, SH-SY5Y cells were first induced toward neuronal cells, after which they were exposed to the hDPSC secretome. In addition, SH-SY5Y cells subjected to the hDPSC secretome showed increased neuritogenesis compared with nonexposed cells. Maturated cells were shown to increase immune reactivity for neuronal markers compared with controls. Ultrastructurally, retinoic acid (RA) signaling and subsequent exposure to the hDPSC secretome induced a gradual rise in metabolic activity and neuronal features such as multivesicular bodies and cytoskeletal elements associated with cellular communication. In addition, electrophysiological recordings of differentiating cells demonstrated a transition toward a neuronal electrophysiological profile based on the maximum tetrodotoxin (TTX)-sensitive, Na+ current. Moreover, conditioned medium (CM)-hDPSC-maturated SH-SY5Y cells developed distinct features including, Cd2+-sensitive currents, which suggests that CM-hDPSC-maturated SH-SY5Y acquired voltage-gated Ca2+ channels. The results reported in this study demonstrate the potential of hDPSCs to support differentiation and recruitment of cells with neuronal precursor characteristics in a paracrine manner. Moreover, this in vitro experimental design showed that the widely used SH-SY5Y cell line can improve and simplify the preclinical in vitro research on the molecular mechanisms of stem cell-mediated neuronal regeneration.

Chronic hibernating myocardium in sheep can occur without degenerating events and is reversed after revascularization.

INTRODUCTION: Our goal was to show that blunting of myocardial flow reserve is mainly involved in adaptive chronic myocardial hibernation without apparent cardiomyocyte degeneration. METHODS AND RESULTS: Sheep chronically instrumented with critical multivessel stenosis and/or percutaneous transluminal coronary angioplasty (PTCA)-induced revascularization were allowed to run and feed in the open for 2 and 5 months, respectively. Regional myocardial blood flow (MBF) with colored microspheres, regional and global left ventricular function and dimensions (2D echocardiography), and myocardial structure were studied. In sheep with a critical stenosis, a progressive increase in left ventricular end-diastolic and end-systolic cavity area and a decrease in fractional area change were found. Fraction of wall thickness decreased in all left ventricular wall segments. MBF was slightly but not significantly decreased at rest at 2 months. Morphological quantification revealed a rather small but significant increase in diffusely distributed connective tissue, cardiomyocyte hypertrophy, and presence of viable myocardium of which almost 30 % of the myocytes showed depletion of sarcomeres and accumulation of glycogen. The extent of myolysis in the transmural layer correlated with the degree of left ventricular dilation. Structural degeneration of cardiomyocytes was not observed. Balloon dilatation (PTCA) of one of the coronary artery stenoses at 10 weeks revealed recovery of fraction of wall thickness and near normalization of global subcellular structure at 20 weeks. CONCLUSION: These data indicate that chronic reduction of coronary reserve by itself can induce ischemic cardiomyopathy characterized by left ventricular dilatation, depressed regional and global function, adaptive chronic myocardial hibernation, reactive fibrosis and cardiomyocyte hypertrophy in the absence of obvious degenerative phenomena. SUMMARY: Reduction of myocardial flow reserve due to chronic coronary artery stenosis in sheep induces adaptive myocardial hibernation without involvement of degenerative phenomena.

Treatment of nonunion of the humerus using the Ilizarov external fixator.

Ilizarov's method of monofocal compression was used in 30 humeri with a diaphyseal pseudarthrosis. Twenty-one patients had previous surgery but had loosening of the osteosynthesis material. Nine patients initially were treated with a hanging cast, resulting in interfragmentary distraction. Fourteen nonunions were hypertrophic, and 16 were atrophic, of which six were infected. A complete circular frame was used only in the first nine patients, whereas the remaining 21 patients were treated with the modified semicircular fixator. Union was obtained in all but two patients, with an average consolidation time of 4.5 months (range, 2.5-10 months). No patient required additional bone grafting. Apart from superficial pin tract infection seen in most of the patients, three had a minor temporary sensory neurologic problem. Four patients experienced a second fracture after removal of the fixator that required a second application of an Ilizarov frame. Although similar results with regard to union are reported after plate osteosynthesis, there was no radial nerve palsy or deep infection in this series, indicating that the treatment by the Ilizarov technique is associated with less complications. The authors' findings suggest that the Ilizarov method is a reliable treatment for humeral nonunions, even after multiple previous operations or in the event of infection.

Unstable femoral neck fractures in young adults: treatment with the AO 130-degree blade plate.

OBJECTIVE: To evaluate the clinical outcome of the treatment of unstable femoral neck fractures using the AO 130-degree blade plate. DESIGN: Between 1980 and 1994, thirty-four consecutive patients younger than age fifty years with an unstable intracapsular femoral neck fracture (Garden Types III-IV) were treated with internal fixation. SETTING: University Hospital Gasthuisberg, Leuven, Belgium. INTERVENTION: The AO 130-degree blade plate with an antirotation, 6.5-millimeter, partially threaded cancellous lag screw was used. RESULTS: Nineteen (63.3 percent) patients had an excellent result, seven (23.3 percent) had a good result, three (10 percent) had a fair result, and one (3.3 percent) had a poor result. Delayed union was observed in one case, and avascular necrosis was observed in two cases. Two implants perforated the subchondral bone. CONCLUSION: Stable fixation with the AO 130-degree blade plate avoids damage to the adjacent blood supply to the femoral head and appears to guarantee a good final outcome of unstable intracapsular femoral neck fractures in young adults.

Tibiotalar arthrodesis in the rheumatoid foot.

The results of 14 open ankle arthrodeses in 13 patients with rheumatoid arthritis are reviewed. Ten arthrodeses were treated with Charnley compression clamps (six of these were combined with a fibular strut graft). Three had cannulated screws and one had a fibular strut graft and a short leg walking cast. The mean followup time was 41.2 months. There were five nonunions and one delayed wound healing. The results of the patients treated with fibular strut grafts are far better than the results in patients treated with open ankle arthrodesis without grafting procedure. This seems a promising technique in a patient population with rheumatoid arthritis.

Unstable femoral neck fractures treated with a 130 degrees blade plate.

We reviewed 32 patients who sustained an unstable intracapsular hip fracture, treated with an AO 130 degrees blade plate. The low incidence in complications (avascular necrosis 7%, delayed union 3%, no nonunion or loss of fracture reduction) compares favorably with previous reports. Experience with this highly demanding surgical technique is however essential to obtain good results.

Quadriceps tendon rupture complicating patellar tendon release.

Injuries to the extensor mechanism of the knee require a profound rehabilitation. The authors present a case in which postsurgical weakening was complicated by quadriceps tendon rupture.