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51.
Nikolaos G. Lasanianos Christos Garnavos Evangelos Magnisalis Stavros Kourkoulis George C. Babis 《Injury》2013
Aim
To compare the biomechanical properties of a newly proposed technique, utilizing intramedullary nailing and compression bolts, for the osteosynthesis of intra-articular proximal tibial fractures with meta–diaphyseal comminution, with modern and conventional plating techniques.Methods
Fifteen left tibia 4th generation composite Sawbones models (in 3 groups of 5 for each technique) with identically reproduced type VI Schatzker tibial plateau fractures, including meta–diaphyseal dissociation, were used. Three different techniques of osteosynthesis were tested: (a) a new technique that combines intramedullary nailing and compression bolts, (b) internal fixation with a single lateral locking plate and (c) internal fixation with dual buttress plating technique. The model-device constructs were successively subjected to 500 N, 1000 N and 1500 N load levels with five cycles applied at each level on both articular compartments and a final load cycle to failure. Four parameters were recorded for each technique: the average reversible or irreversible displacement in vertical subsidence, the horizontal diastasis of the intra-articular fracture, the average passive construct stiffness and the load to failure.Results
The new intramedullary nailing technique provided rigid intra-articular osteosynthesis being statistically similar to dual buttress plating for subsidence at medium and higher load levels. At the same time the proposed technique provided statistically equivalent stiffness values to the single lateral locking plate incarnating the rational of biologic fixation. Average load to failure was 1611 N for single lateral locking plates, 2197 N for intramedullary nailing and 4579 N for dual buttress plating. The single lateral locking plate technique had the worse results in interfragmentary displacement while dual buttress plating was superior in stiffness from the other 2 techniques. The mode of failure differed between techniques, with collapse of medial plateau occurring exclusively in the single lateral locking plates group.Conclusion
The proposed new technique of intramedullary nailing and compression bolts demonstrates a flexural behaviour similar to single lateral locking plates, which complies with the terms and benefits of biological fixation, while at the same time maintains a rigid intra-articular stability similar to the stiff dual buttressing plating technique. 相似文献52.
Stavros G. Memtsoudis MD PhD Mary Hargett BS Linda A. Russell MD Javad Parvizi MD William L. Cats-Baril PhD Ottokar Stundner MD Thomas P. Sculco MD 《Clinical orthopaedics and related research》2013,471(8):2649-2657
Background
Controversy exists regarding many aspects of decision making pertaining to same-day versus staged bilateral TKA (BTKAs), including patient selection, perioperative management decisions, and other important choices.Questions/purposes
In the absence of suitable randomized trials, we sought to determine areas of consensus among national experts on the following questions: (1) What are the comparative risks of same-day BTKAs compared with unilateral TKA (UTKA) and staged BTKAs? (2) Who should be considered an appropriate candidate for same-day BTKAs? (3) What constitutes appropriate workup and perioperative management for BTKAs? (4) What is the optimal time between procedures if same-day BTKAs are not deemed appropriate? (5) Are there orthopaedic or rehabilitation considerations for BTKAs that might outweigh medical contraindications?Methods
In the setting of a consensus conference of national experts in orthopaedic surgery, anesthesiology, perioperative medicine, and epidemiology, the major questions surrounding same-day BTKAs were addressed by using an extensive literature review and the modified Delphi process. The process concluded with a meeting of participants and formulation of consensus statements.Results
Eighty-one percent of participants agreed that BTKAs are more invasive and complex procedures associated with increased risk for perioperative adverse events compared with UTKA in an unselected group of patients. The consensus group agreed that physicians and hospitals should consider using more restrictive patient selection criteria and exclude those with a modified cardiac risk index greater than 3 to mitigate the potentially increased risk. The majority of the group agreed that perioperative assessment and management should reflect the higher level of acuity of same-day BTKAs. Eighty-one percent of participants agreed that if a patient is not deemed a candidate for same-day BTKAs, a second TKA should be scheduled no sooner than 3 months after the first. The entire group agreed that when there is a conflict between the orthopaedic need and the medical adequacy of same-day BTKAs, the medical concern for the patient’s safety should prevail over the orthopaedic need.Conclusions
Experts perceived that same-day BTKAs increase medical risk, and thus a systematic approach to the management of patients should be taken to minimize complications.Electronic supplementary material
The online version of this article (doi:10.1007/s11999-013-2976-9) contains supplementary material, which is available to authorized users. 相似文献53.
54.
Kyriakos Anastasiadis MD FETCS Stavros Hadjimiltiades MD FACC Polychronis Antonitsis MD 《Catheterization and cardiovascular interventions》2012,80(5):845-849
Minimal extracorporeal circulation (MECC) represents a contemporary system which integrates several advances in cardiopulmonary bypass technology in a single circuit. We challenged the efficacy of the MECC system to support the circulation in elective high‐risk percutaneous coronary intervention (PCI). A 78‐year‐old patient with complex coronary disease who would have been otherwise rejected for interventional therapy underwent PCI with rotablation on MECC support. The MECC system provided hemodynamic support at a flow of 1.8 L min?1 m?2 while perfusion pressure was kept at a minimum of 70 mm Hg. This allowed for successful angioplasty of the left main stem and a chronically occluded right coronary artery, which otherwise produced significant hemodynamic compromise. This case illustrates that mechanical circulatory support with the MECC system could provide a stable environment and a “safety net” for carrying out complex percutaneous coronary intervention in high‐risk patients. © 2012 Wiley Periodicals, Inc. 相似文献
55.
Joseph A. Blackmon Stavros Atsas Mackenzie J. Clarkson Jacob N. Fox Blake T. Daney Sean C. Dodson H. Wayne Lambert 《The Journal of foot and ankle surgery》2013,52(1):42-47
The sural nerve is at risk of iatrogenic injury even during minimally invasive operative procedures to repair the calcaneal (Achilles) tendon. Through 107 cadaveric leg dissections, the data derived from the present study was used to develop a regression equation that will enable surgeons to estimate the intersection point at which the sural nerve crosses the lateral border of the Achilles tendon, an important surgical landmark. In most cases, the sural nerve crossed the lateral border of the Achilles tendon 8 to 10 cm proximal to the superior border of the calcaneal tuberosity. By simply measuring the leg length of the patient (from the base of the heel to the flexor crease of the popliteal fossa), surgeons can approximate the location of this intersection point with an interval length of 0.68 to 1.80 cm, with 90% confidence, or 0.82 to 2.15 cm, with 95% confidence. For example, for a patient with a lower leg length of 47.0 cm, the mean measurement in the present study, a surgeon can be 90% confident that the sural nerve will cross the lateral border of the Achilles tendon 8.28 to 8.96 cm (interval width of 0.68 cm) proximal to the calcaneal tuberosity. Currently, ultrasound and clinical techniques have been implemented to approximate the location of the sural nerve. The results of the present study offer surgeons another method, that is less intensive, to locate reliably and subsequently avoid damage to the sural nerve during calcaneal (Achilles) tendon repair and other procedures of the posterolateral leg and ankle. 相似文献
56.
Stavros A. Antoniou George A. Antoniou Oliver O. Koch Rudolph Pointner Frank A. Granderath 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2013,17(1):15-22
Background and Objectives:
Laparoscopic treatment of perforated peptic ulcer (PPU) has been introduced as an alternative procedure to open surgery. It has been postulated that the minimally invasive approach involves less operative stress and results in decreased morbidity and mortality.Methods:
We conducted a meta-analysis of randomized trials to test this hypothesis. Medline, EMBASE, and the Cochrane Central Register of Randomized Trials databases were searched, with no date or language restrictions.Results:
Our literature search identified 4 randomized trials, with a cumulative number of 289 patients, that compared the laparoscopic approach with open sutured repair of perforated ulcer. Analysis of outcomes did not favor either approach in terms of morbidity, mortality, and reoperation rate, although odds ratios seemed to consistently support the laparoscopic approach. Results did not determine the comparative efficiency and safety of laparoscopic or open approach for PPU.Conclusion:
In view of an increased interest in the laparoscopic approach, further randomized trials are considered essential to determine the relative effectiveness of laparoscopic and open repair of PPU. 相似文献57.
58.
Mareike Lankeit Claudia Dellas Viola Benz Gerd Hasenfuß Stavros Konstantinides 《Thrombosis research》2013
Background
Heart-type fatty acid-binding protein (H-FABP) is a useful biomarker for risk stratification of patients with pulmonary embolism (PE). In patients with acute myocardial infarction, H-FABP plasma concentrations rise after 30 minutes and return to normal within 20-24 hours. We tested whether the predictive value of H-FABP is affected by the duration of symptoms prior to diagnosis in patients with PE.Material and Methods
We prospectively studied 257 consecutive normotensive patients with confirmed symptomatic PE.Results
Patients with acute (< 24 hours; n = 150) symptom onset presented more often with syncope (28.7% vs. 6.5%; p < 0.001) compared to patients with symptoms ≥ 24 hours (n = 107); other baseline characteristics, comorbidities, and risk factors were distributed equally. Patients with an adverse 30-day outcome (6.6%) had higher H-FABP levels (11.84 [3.57-19.62] ng/ml) compared to patients with a favorable course (3.42 [1.92-5.42] ng/ml; p < 0.001). However, the proportion of patients with H-FABP levels ≥ 6 ng/ml did not differ among patients with acute symptom onset and late presentation (p = 0.104). Only tachycardia and elevation of H-FABP were associated with an increased risk of an adverse 30-day outcome both in patients with acute symptom onset (H-FABP: OR, 5.8; 95% CI, 1.4-24.5; p = 0.016; tachycardia: 7.0 [1.4-36.0]; p = 0.018) and late presentation (H-FABP: 9.3 [2.0-43.2]; p = 0.004 and tachycardia: 12.3 [1.5-103.6]; p = 0.021). The prognostic value could further be improved by the use of a simple H-FABP-based clinical prediction score.Conclusions
Our findings indicate that H-FABP is a useful biomarker for risk stratification of normotensive patients with PE regardless of symptom duration prior to diagnosis. 相似文献59.
Krasanaki ME Pelekanos S Andreiotelli M Koutayas SO Eliades G 《The International journal of prosthodontics》2012,25(2):170-172
This study evaluated the influence of two preparation types on the marginal fit of computer-aided design/computer-assisted manufacture (CAD/CAM) alumina copings. Two subgroups of four alumina copings each were fabricated using alumina master dies with either a chamfer or 90-degree shoulder preparation. Copings were scanned with an x-ray microtomographic scanner, and marginal fit was evaluated. The preparation types presented no statistically significant differences regarding marginal gap (P = .410) and absolute marginal discrepancy (P = .229). No correlation was found between marginal fit of CAD/CAM alumina copings and preparation type. Marginal fit could be considered within the limits of clinical acceptance. 相似文献