Postfusion effect on pullout strength of pedicle screws with expandablepeek shell and conventional screws.

The pullout performance of various pedicle screws after artificial fusion process was investigated in this study. Normal, cannulated (cemented), novel expandable and normal (cemented) pedicle screws were tested. Polyurethane foams (Grade 10 and Grade 40) produced by casting method were used as test materials. The instrumentation of pedicle screws has been carried out with production of foams, simultaneously. For cemented pedicle screws, 3D models were prepared with respect to the anteriosuperior and oblique radiographs by using PMMA before casting procedure. Pullout tests were performed in an Instron 3369 testing device. Load versus displacement graph was recorded and the ultimate force was defined as the pullout strength sustained before failure of screw. As expected, the pullout strengths of pedicle screws in postfusion are higher than before fusion. Pullout strengths increased significantly by artificial fusion in Grade 10 foams compared to Grade 40 foams. Additionally, while the pullout strengths of normal, cannulated and novel expandable pedicle screws increased by artificial fusion, cemented normal pedicle screws had lower pullout values than before fusion in Grade 40 foams. When the cemented normal pedicle screws are excluded, other screws have almost similar pullout strength level. On the other hand, the pedicle screws have different increasing behaviour also, there is no correlation between each other. As a result, the novel expandable pedicle screws can be used instead of normal and cannulated ones due to their performances in non-cemented usage.

The effect of alginate scaffolds on bone healing in defects formed with drilling model in rat femur diaphysis.

Alginate (ALG) is a biocompatible and biodegradable polymer. Mechanical weakness is one of the main problems for the alginate-based scaffolds. Various plasticizer additives or modifications tested to improve the mechanical properties. In the presented study, ALG plasticized with triacetin (TA), and tributyl citrate (TBC) than tested on bone healing. In the presented study, the alginate modified with triacetin or tributyl citrate. In-vitro, and in-vivo efficiency of the scaffolds tested on bone tissue regeneration. Scaffolds fabricated by solvent casting, and physicochemical characterizations performed. Monocytes (THP-1) cultured with scaffolds, and macrophage-released cytokines was determined. In-vivo efficacy of the scaffolds was tested in the rat drill hole model. Alginate and tributyl citrate-modified scaffolds have no cytotoxic effect on osteoblastic cells (MC-3T3). Tributyl citrate modification increased tumor necrosis factor-alpha (TNF-alpha) level but did not increase interleukin -1 beta (IL-1 beta) level. In vivo studies showed that osteoblastic growth was significant in alginate and triacetin-modified scaffolds. However, the best values for osteoclastic activity and osteoid tissue formation seen in the triacetin modification. The results demonstrated that the modified alginate scaffolds were more successful than non-modified alginate scaffolds and can used as long-term bone repairing treatments.

A study on bone tissue engineering: Injectable chitosan-g-stearic acid putty.

BACKGROUND: Bioengineering products can help bone tissue regeneration. OBJECTIVE: There is an ongoing research for more effective biomaterials in bone regeneration. Chitosan (Ch) grafted stearic acid (Ch-g-Sa) polymer was synthesized and its usability as a putty was evaluated in this study. METHODS: The chemical structure of Ch-g-Sa polymer was investigated using Proton nuclear magnetic resonance (H-NMR) and Fourier-transformed infrared spectroscopy-attenuated total reflectance (FTIR-ATR). Thermal properties of Ch-g-Sa polymer were determined by thermal gravimetric analysis (TGA). Putties containing nano-hydroxyapatite were prepared and in-vitro degradation properties and viscosity of the putties were determined. RESULTS: The cytotoxicity, oxidation effect and osteogenic potential of the putties were investigated on MC3T3 cells while the inflammatory effect of the putties was studied on THP-1 cells. For the determination of the osteogenic effect of the putties, ALP and RUNX2 gene expression of MC3T3 cells were studied. CONCLUSION: Ch-g-Sa/HA putties are promising biomaterials for bone tissue regeneration.

Rhythm and orthopedics: The effect of music therapy in cast room procedures, a prospective clinical trial.

INTRODUCTION: Cast room procedures generally cause anxiety in patients. Anxiety complicates the procedure as well as increases the risk of a complication. Listening to music was found to be the safest and most common non-drug treatment method. The aim of this study is to evaluate the effect of listening to music on adult patients in cast room procedures. This study points out the relation between anxiety and anxiety relevant cardiac arrhythmia. MATERIALS AND METHODS: The study was performed on 199 patients with stable general condition, aged above 18. The patients were divided into two groups. Randomization method used in the study was coin flip. The first group (Group 1) listened to music during cast room procedures whereby the second group (Group 2) did not listen to music. Length of the procedure, complication, blood pressure and heart rate evaluations before and after the procedure, Visual Analogue Scale (VAS scores for pain), State-Trait Anxiety Inventory (STAI) anxiety score, patient satisfaction, willingness of the patient to repeat the procedure, P wave dispersion (Pd) and corrected QT interval dispersion (QTcd) as electrocardiographic arrhythmia predictors were evaluated. The Clinical Research Ethics Committee approval was obtained for this study. RESULTS: Significant difference was shown between the two groups for the following criteria: VAS scores (p = 0.005), anxiety scores (p = 0.032), processing time (p = 0.027), and QTcd values (p = 0.031). Patient satisfaction (p < 0.001) and willingness to repeat the procedure (p < 0.001) were higher for the group who listened to music. No significant difference in Pd values, blood pressure and heart rate was reported within the groups. CONCLUSION: Music therapy is a non-invasive, safe, nonpharmacologic, anxiolytic, and analgesic treatment. Music therapy should become standard protocol in cast room procedures. One of the most important achievements of this study was the fact that music decreases anxiety and anxiety-related cardiac arrhythmia. Therefore, conducting further prospective studies including high cardiac risk patients especially with arrhythmia is crucial.

The Comparison of Pullout Strengths of Various Pedicle Screw Designs on Synthetic Foams and Ovine Vertebrae.

AIM: One of the most common problems with transpedicular screws is screw pullout. This study was conducted to measure the pullout strengths of newly designed transpedicular screws. MATERIAL AND METHODS: The design of the three group screws were conical cored standard pedicle screw (Type A), dual threaded pedicle screw (Type B), dual core and dual threaded pedicle screw (Type C), respectively. Polyurethane (PU) blocks in 25 mm and 50 mm thickness were used to investigate the effect of just the pedicle on pullout strength and both distal (vertebral body) and proximal (pedicle) parts of the screw. The screws were also tested in ovine lumbar vertebrae. RESULTS: Type C screw exhibited 5.9% and 12.9% higher pullout strength than Type A and Type B, and 15.4% and 8.6% higher pullout strength than Type A and Type B, respectively on 25 mm and 50 mm thick PU foam block. Type C also exhibited 74.5% and 22.5% higher pullout strength than Type A and Type B, respectively on the ovine vertebrae. CONCLUSION: Transpedicular screws redesigned with modified helical angles exhibit higher pullout strength compared to the classical transpedicular screws and can be inserted more rapidly with the same number of screwing rounds result with doubled insertion depth.

A critical appraisal of the North American Spine Society guidelines with the Appraisal of Guidelines for Research and Evaluation II instrument.

BACKGROUND CONTEXT: The North American Spine Society (NASS) publishes clinical guidelines that are taken into consideration worldwide by clinicians who have a special interest in spinal surgery. The Appraisal of Guidelines for Research and Evaluation (AGREE) II is the second version of the original AGREE instrument to assess the quality of guidelines in terms of development process. This appraisal aims to evaluate each individual NASS guideline using AGREE II tool to demonstrate its methodologic robust and weakness. PURPOSE: To evaluate the quality of the clinical practice guidelines published by the NASS. STUDY DESIGN: Four appraisers used the AGREE II guideline evaluation instrument to evaluate the NASS guidelines. METHODS: All six guidelines available on the NASS web site as of July 1, 2014 were evaluated. Four reviewers independently assessed these guidelines using the AGREE II instrument. The instrument standardizes the quantitative assessment of quality for a guideline's development process across six domains that include: scope and purpose, stakeholder involvement, rigor of development, clarity and presentation, applicability, and editorial independence. Additionally, each reviewer rated the overall quality of the guidelines. RESULTS: Overall results for the AGREE II domains across all six guidelines were: scope and purpose (median score, 94.4%), stakeholder involvement (median score, 56.9%), rigor of development (median score, 91.7%), clarity of presentation (median score, 94.4%), applicability (median score, 60.9%), and editorial independence (median score, 71.9%). CONCLUSIONS: Our study showed that the quality of the NASS guidelines needs some improvement. There is a critical need for broader stakeholder involvement including patient representatives and health economists. Consideration of resource implications and monitoring process and standardization of how recommendations are implemented need to be improved. Studies analyzing facilitators and barriers would be helpful for future NASS guidelines.

The results of minimally invasive percutaneous plate osteosynthesis (MIPPO) in distal and diaphyseal tibial fractures.

OBJECTIVE: The aim of this study was to evaluate the time to union and complications in cases of tibial diaphysis and distal tibial fractures fixed with a minimally invasive percutaneous plate. METHODS: Thirty-five patients (23 males, 12 females) were operated on using minimally invasive percutaneous plate osteosynthesis (MIPPO) principles for tibial diaphysis and distal tibial fractures. Twenty-eight were closed and seven were open fractures. After direct or indirect fracture reduction, the plate was advanced through a submuscular extraperiosteal tunnel through the distal incision without opening the fracture line. The plate was fixed with screws through the proximal and distal incisions. Clinical and radiological evaluations were made at four to six week intervals after surgery. Full weight-bearing was allowed after an average of 14.43 (range: 12 to 20) weeks and 15.39 (range: 8 to 32) weeks in open and closed fractures, respectively. Duration of the union and complications were analyzed. RESULTS: The mean duration of the union was 20.7 (range: 16 to 28) weeks and 17.96 (range: 10 to 36) weeks in open and closed fractures, respectively. All cases showed union except one who had an implant failure. Necrosis at the wound developed in one case and infection in another. CONCLUSION: MIPPO is an effective alternative treatment for tibial diaphysis and distal tibia fractures with low complication and high union rates.