The effectiveness of germicidal wipes and ultraviolet irradiation in reducing bacterial loads on electronic tablet devices used to obtain patient information in orthopaedic clinics: evaluation of tablet cleaning methods.

BACKGROUND: Electronic tablet devices are commonly used in outpatient clinics to obtain patient information for both clinical and research purposes. These devices are often colonized with bacteria; there are many cleaning methods to reduce this bacterial load. AIM: The primary purpose of this study was to evaluate whether regular cleaning with either germicidal wipes or ultraviolet (UV) irradiation leads to lower bacterial levels compared with irregular cleaning. METHODS: A randomized blinded trial was conducted of tablet cleaning strategies between each patient encounter in orthopaedic clinics. The cleaning method was randomized to either germicidal wipes, UV irradiation, or cleaning only when the tablet was visibly soiled. Research assistants (blinded to the treatment) obtained bacterial cultures from the tablets at the beginning and end of each clinic day. FINDINGS: Using germicidal wipes between each patient encounter vs no routine cleaning resulted in a marked decrease in the amount of bacterial contamination (risk ratio (RR) = 0.17 (0.04-0.67)). Similarly, using UV irradiation between each patient encounter led to significantly lower bacterial contamination rates (RR = 0.29 (95% confidence interval (CI) = 0.09-0.95)) compared with no routine cleaning. The majority of bacteria identified were normal skin flora. No meticillin-resistant Staphylococcus aureus was identified and only sparse colonies of meticillin-sensitive S. aureus. CONCLUSION: Electronic tablets used in orthopaedic trauma clinics are colonized with bacteria if no routine cleaning is performed. Routine use of either UV irradiation or germicidal wipes significantly decreases this bacterial burden. Providers should implement routine cleaning of tablets between each patient encounter to minimize exposure to potential pathogens.

Impact of Sagittal Balance on Clinical Outcomes in Surgically Treated T12 and L1 Burst Fractures: Analysis of Long-Term Outcomes after Posterior-Only and Combined Posteroanterior Treatment.

Objective. Long-term radiological and clinical outcome retrospective study of surgical treatment for T12 and L1 burst fractures in perspective of sagittal balance measures. Methods. Patients with age of 16-60 years, complete radiographs, early surgical treatment surgery, and follow-up (F/U) > 18 months were included and strict exclusion criteria applied. Regional and thoracolumbar kyphosis angles (RKA and TLA) were measured preoperatively and at final F/U, as were parameters of the spinopelvic sagittal alignment. Clinical outcomes were assessed using validated measures. Results. 36 patients with age mean age of 39 years and F/U of 69 months were included. 61% of patients were treated with bisegmental posterior instrumentation (POST-I) and 39% with combined posteroanterior instrumented fusion (PA-F). At F/U, several indicators for clinical outcomes showed a significant correlation with radiographic measures in the overall cohort with inferior clinical outcomes corresponding with increasing residual deformity and sagittal malalignment. Statistical analysis failed to reach level of significance for the differences between POST-I and PA-F group at final F/U. Only a strong trend towards better restoration of the thoracolumbar alignment was observed for the PA-F group in terms of the RKA and TLA. Conclusions. Results in a surgically treated cohort of T12 and L1 burst fracture patients indicate that superior clinical outcomes depend on restoration of sagittal alignment.

Efficacy of common surgical compounds in preventing articular chondrocyte death from desiccation.

PURPOSE: Purpose of this study was to identify potential substances that prevent desiccation of chondrocytes. METHODS: Macroscopically normal bovine cartilage explants (n = 80) were exposed to room air, or covered with surgical lubricant, Lactated ringer (LR) or Seprafilm (Genzyme Biosurgery, Cambridge, MA) for 0, 30, 60 or 120 min. The viability of superficial chondrocytes was measured after 48 h of incubation in tissue culture media at 37 °C by Live/Dead staining. Chondrotoxicity was measured as the extent of cell death below the articular surface. Statistical analysis was performed with a two-way analysis of variance on the data set and a subsequent Tukey's post hoc test. RESULTS: Chondrocyte death correlated positively with the length of exposure, regardless of the treatment (p < 0.0001). The extent of superficial chondrocyte death was minimally lower in the LR (89.1 ± 2.6 %, 80.8 ± 1.2 %) and surgical lube (84.3 ± 1.8 %, 75.9 ± 2.7 %) groups than the control (82 ± 5.7 %, 65.6 ± 13.3 %) and Seprafilm group (77.6 ± 3.9 %, 63.3 ± 6.9 %) (p < 0.001) at the first two time points, with no significant difference between the latter groups. After 60 and 120 min, surgical lube resulted in less chondrocyte death than all other groups (70.4 ± 6.8 % and 60.9 ± 5.9 %, all p < 0.0001). CONCLUSION: The data suggest that depending on the expected length of exposure of the articular cartilage surface, different compounds appear to be protective. For exposures exceeding 60 min, surgical lubricant demonstrated the highest protective potential. Results from this study indicate that protecting exposed articular surfaces with surgical lubricant for orthopaedic procedures lasting more than 1 h lead to decreased chondrocyte death and suggest improved cartilage functional outcomes postoperatively.

Patient satisfaction after primary total and unicompartmental knee arthroplasty: an age-dependent analysis.

BACKGROUND: Patient-related outcomes have become the focus of increased attention when assessing knee arthroplasty. METHODS: We retrieved questionnaires from 485 (584 knees) patients at a minimum of 3years after undergoing primary knee arthroplasty. We excluded bilateral knee arthroplasty, leaving 141 UKA and 245 TKA who rated their satisfaction and expectation regarding pain, range of motion (ROM), daily living function (DLF), return to recreational activity (RRA) and ability to kneel (ATK) on a scale of 0 (worst) to 10 (best). We further collected data on pain level and the modified Cincinnati rating scale. Range of motion was documented pre- and postoperatively at a minimum of six months. The cohort was subdivided into three age groups and compared with each other (Group 1: <55, n=113; Group 2: 55-64, n=117; Group 3: 65+, n=155). RESULTS: Average satisfaction with pain, ROM and ATK for patients under 55 was higher for UKA than for TKA. Patients>65 with TKA were on average more satisfied than patients with UKA in these three items. However, patients under 55 with UKA were up to 2.9 times more likely to have their expectations met when compared to patients receiving TKA. Patients with UKA under 55 rated their joint as good/excellent in 96.0% versus patients in the same age group with TKA in 81.0%. CONCLUSIONS: We found that overall, younger patients who were treated with UKA demonstrated higher satisfaction scores in most subsets when compared with the patients of the same age group who received TKA.

Nonlinear evolution of surface morphology under shadowing.

Fluorocarbon thin-film deposition is studied, which shows an anomalous high dynamic growth exponent and therefore does not fit in any universal class of fractal surface growth models. A detailed analysis of the nonlinear behavior of the surface morphology evolution is carried out, quantifying several features of the shadowing instability. A synergy effect with the Kardar-Parisi-Zhang nonlinearity, which couple the large scales induced by shadowing with intermediate scales, may explain the anomalous high growth exponent.

[Evidence-based therapy for cartilage lesions in the knee - regenerative treatment options]. / Evidenzbasierte Knorpeltherapie im Kniegelenk - regenerative Behandlungsoptionen.

BACKGROUND: The treatment of cartilage defects has seen a shift from replacement to regeneration in the last few years. The rationale behind this development is the improvement in the quality-of-care for the growing segment of young patients who are prone to arthroplasty complications because of their specific characteristics - young age, high level of activity, high demand for functionality. These days, two of the most popular regenerative treatments are microfracture and autologous chondrocyte implantation (ACI). Although these new options show promising results, no final algorithm for the treatment of cartilage lesions has been established as yet. MATERIALS AND METHODS: The objective of this review is to describe and compare these two treatment options and to present an evidence-based treatment algorithm for focal cartilage defects. RESULTS: Microfracture is a cost-effective, arthroscopic one-stage procedure, in which by drilling of the subchondral plate, mesenchymal stem cells from the bone marrow migrate into the defect and rebuild the cartilage. ACI is a two-stage procedure in which first chondrocytes are harvested, expanded in cell culture and in a second open procedure reimplanted into the cartilage defect. Microfracture is usually used for focal cartilage defects < 4 cm2, the treated defect size of the ACI seems to have a wider range. The effectiveness of these two treatments has been shown in long-term longitudinal studies, where microfracture showed improvement in up to 95 % of patients, whereas 92 % of the patients in a 2-9 year period of follow-up after ACI showed improvements, respectively. The successful outcome of the treatment depends on multiple factors such as the location of the defect, cell differentiation and proliferation, concomitant problems, and the age of the patient. Associated complications and disadvantages of the two different applications are, for the microfracture patient, a poor tissue differentation or a formation of an intra-lesional osteophyte, and for the ACI patient, periosteal hypertrophy and the need for two procedures in ACI. Only a few studies provide detailed and evidence-based information on a comparative assessment. These studies, however, are showing widely similar clinical outcomes but better histological results for ACI, which are likely to translate into better long-term outcomes. CONCLUSIONS: Although evidence-based studies comparing microfracture and ACI have not found significant differences in the clinical outcome, the literature does show that choosing the treatment based on the size and characteristics of the osteochondral lesion might be beneficial. The American Association of Orthopedic Surgeons suggest that contained lesions < 4 cm2 should be treated by microfracture, lesions bigger than that by ACI.

Radiological evaluation of cartilage after microfracture treatment: a long-term follow-up study.

INTRODUCTION: Recent literature revealed good short-term results after microfracturing (MFX) of isolated focal cartilage defects in the knee joint. Study purpose was a long-term evaluation of patients who received MFX through a multimodal approach, correlating clinical scores and morphological pre- and postoperative MRI-scans. MATERIALS AND METHODS: Between 2000 and 2007 158 patients were treated with MFX for focal femoral or tibial defects at our department. Patients with instabilities, secondary surgical intervention, patellofemoral lesions, a plica mediopatellaris or more than one cartilage defect site and age >55 were excluded. 15 patients were included. Minimum postoperative follow-up (FU) was 18 months (18-78 m). Mean age at surgery was 45 years (27-54), mean FU-interval 48 months (18-78 m). Male to female ratio was 9:6. For clinical assessment the Knee Osteoarthritis Ou tcome Score (KOOS) and Lysholm Score were used, radiological evaluation was performed with radiographs and 3Tesla-MRI. RESULTS: Clinical knee function was rated good to excellent in 1 patient, fair in 2 and poor in 10 patients. 2/15 patients received full knee replacement due to insufficient cartilage repair through MFX during FU period. Evaluation of pre- and postoperative MRI showed good cartilage repair tissue in 1 (7.7%), moderate repair in 2 (15.4%) and poor fill in 10 patients (76.9%). In these 10 patients the defect size increased. Average defect size preoperatively was 187 mm(2) (range 12-800 mm(2)) and postoperatively 294 mm(2) (40-800 mm(2)). The KOOS-Pain averaged 60 (39-94), KOOS-Symptoms 60.6 (21-100), KOOS-ADL 69 (21-91), KOOS-Sports 35.7 (5-60) and KOOS-QUL 37.2 (6-81). The average Lysholm Score was 73.9 (58-94). 10 patients showed a varus leg axis deviation (Ø 5.9°), 3 had a neutral alignment. The alignment correlated positively with KOOS and especially with the Lysholm Score. CONCLUSION: Our study demonstrated that MFX as a treatment option for cartilage defect in the knee did not show the anticipated clinical and radiological long-term results. In 12 of 15 patients the cartilage defect size had increased after MFX, in 2 patients indicating full-knee replacement. Especially those with a leg malalignment >5° in varus were more prone to suffer from an increase in defect size. In our cohort the clinical scores correlated with the radiological findings.

Molecular beam sampling system with very high beam-to-background ratio: the rotating skimmer concept.

A novel method of reducing the background pressure in a vacuum system used for sampling a molecular beam from a high pressure region is presented. A triple differential pumping stage is constructed with a chopper with rotating skimmer within the first pumping stage, which serves effectively as a valve separating periodically the vacuum system from the ambient environment. The mass spectrometry measurement of the species in the molecular beam show an excellent beam-to-background ratio of 14 and a detection limit below 1 ppm. The potential of this method for detection of low density reactive species in atmospheric pressure plasmas is demonstrated for the detection of oxygen atoms generated in an atmospheric pressure microplasma source.

Initial polymerization reactions in particle-forming Ar/He/C2H2 plasmas studied via quantitative mass spectrometry.

The initial polymerization reactions in particle forming Ar/He/C 2H 2 plasmas are studied using molecular beam mass spectrometry (MBMS). The measured mass spectra are disentangled and quantified with the help of Bayesian probability theory. This approach uses the measured mass spectra and the cracking patterns (CPs) of the species that are formed in the plasma as the main input parameter. The CPs are either taken from calibration measurements or the NIST database or estimated based on a comparison to CPs of similar molecules. These estimated CPs are then modified by Bayesian analysis to fit the measured data. The CPs of C 6H 2, C 6H 4, and C 8H 2, which are not available in the NIST database, are determined in this way and can serve as good estimation until precise data is published. The temporal evolution after plasma ignition of the densities of in total 22 species (hydrocarbons, noble gases, and impurities) are quantified and expressed as partial pressures. The most abundant products in our plasma are C 4H 2 and C 6H 2 molecules with maximum partial pressures of 0.1 and 0.013 Pa, respectively. Our quantitative data can be used to validate plasma chemistry models. First comparison is made to a plasma chemistry model of similar C 2H 2 plasma already available in the literature. The comparison indicates that dissociative electron attachment to C 2 n H 2 ( n > 1) molecules is a dominant source of negative ions in C 2H 2 plasmas. Additionally, the C 2H 4 has been identified as a precursor for C n H 4 molecules.

Time-resolved molecular beam mass spectrometry of the initial stage of particle formation in an Ar/He/C2H2 plasma.

The temporal evolution of the neutral plasma chemistry products in a capacitively coupled plasma from argon/helium/acetylene is followed via molecular beam mass spectrometry with a time resolution of 100 ms. Several chemistry pathways are resolved. (i) The formation of C2nH2 (n = 2-5) molecules proceeds via the following sequence: the production of highly reactive C2H radicals in electron impact dissociation of C2H2 is followed by C2H induced chain polymerization of C2nH2 (n = 1-4). (ii) CnH4 (n = 4, 5, 6) compounds are detected already at an early stage of the discharge excluding polymerization reactions with C2H radical being responsible for their formation. Instead, vinylidene reactions with acetylene or mutual neutralization reactions of ionic species are proposed as sources of their formation. (iii) Surface reactions are identified as the source of C8H6. The measured hydrocarbon molecules represents possible precursors for negative ion formation via dissociative electron attachment reactions and can hence play a crucial role in particle nucleation. On the basis of the comparison of our data with available experimental and modeling results for acetylene plasmas in the literature, we propose C2nH2 (n > 1) molecules as important precursors for negative ion formation.