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81.
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Anna C. Rienmüller Sandro M. Krieg Franziska A. Schmidt Elias L. Meyer Bernhard Meyer 《The spine journal》2019,19(1):113-120
Background Context
The concept of dynamic stabilization (DS) of the lumbar spine for treatment of degenerative instability has been introduced almost two decades ago. Dynamic stabilization follows the principle of controlling movement in the coronal plane by providing load transfer of the spinal segment without fusion and, at the same time, reducing side effects such as adjacent segment disease (ASD). So far, only little is known about revision rates after DS due to ASD and screw loosening (SL).Purpose
The present study aimed to evaluate the longitudinal revision rates following dynamic pedicle screw stabilization in the lumbar spine and to determine specific risk factors predictive for ASD, SL, and overall reoperation in a large cohort with considerable follow-up.Design
We carried out a post hoc analysis of a prospectively collected database in a level I spine center.Patients Example
The patient sample comprised 283 (151 female/132 male) consecutive patients suffering from painful degenerative lumbar segmental instability with or without spinal stenosis who underwent DS of the lumbar spine (Ulrich Cosmic, Ulrich Medical, Ulm, Germany) between January 2008 and December 2011.Outcome Measures
Longitudinal reoperation rate and risk factors predictive for revision surgery were evaluated.Methods
We analyzed the longitudinal reoperation rate due to ASD and SL and overall reoperation. Risk factors such as age, gender, body mass index, lumbar lordosis (LL), number of segments, and number of previous surgeries were taken into account. Regular and mixed model logistic regressions were performed to determine risk factors for revision surgery on a patient and on a screw level.Results
The mean age was 65.7±10.2 years (range 31–88). One hundred thirty-two patients were stabilized in 1 segment, 134 in 2 segments, 15 in 3 segments, and 2 patients in 4 segments. Reoperation rate for ASD and SL after 1 year was 7.4 %, after 2 years was 15.0%, and after a mean follow-up of 51.4±15 months was 22.6%. Reasons for revision were SL in 19 cases (6.6%), ASD in 39 cases (13.7%), SL and ASD in 6 cases, hematoma in 2 cases (0.7%), cerebrospinal fluid fistulae in 3 cases (1.1%), infection in 6 cases (2.1%), and implant failure in 1 case (0.4%). The patients' age, the number of stabilized segments, and the number of previous surgeries and postoperative LL had a significant influence on the probability for revision surgery.Conclusions
Reoperation rates after DS of the lumbar spine are comparable with rigid fixations. The younger the patient and the more segments are involved, the lower the LL and the more previous surgeries were found, the higher was the risk of revision. Risk of revision was almost twice as high in men compared with women. We therefore conclude that for clear clinical indication and careful evaluation of preoperative imaging data, DS using the Cosmic system seems to be a possible option. The presented data will help to further tailor indication and patient selection. 相似文献83.
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85.
Anton A. Semenistyy Elena A. Litvina EA Anna G. Fedotova Chukwuweike Gwam Andrey N. Mironov 《Injury》2019,50(2):515-520
Background
Intramedullary nailing is considered a “gold standard” for treatment of tibial shaft fractures. However, some types of fractures are typically considered as “difficult for nailing”. This group includes the periarticular fractures, fractures of both bones at the same level, comminuted and segmental fractures of the tibia. Fixator-assisted nailing (FAN) is an effective method treatment of these types of fractures. The main requirements for the ideal reduction device are an ease of its installation and an ability of multiplanar fracture reduction. Fixator-assisted nailing (FAN) with the use of two perpendicular to each other monolateral tubular frames perfectly meets these requirements. In this study we present this new surgical technique and the analysis of first 30 cases.Methods
A prospective analysis was conducted for 30 patients with “difficult for nailing” tibial fractures treated with fixator-assisted nailing in our institution between September 1st, 2017, and March 1st, 2018. The duration of surgery and its different stages, the time of fluoroscopy, difficulties encountered during surgery, were analyzed. Clinical and radiological methods were used to evaluated reduction quality.Results
In all 30 cases the acceptable reduction was achieved. The mean duration of the surgical procedure was 73.7?±?3?min. The mean duration of fluoroscopy 85.9?±?4.8?s. In 7 cases we faced with technical difficulties, which were successfully addressed.Conclusion
The described technique of FAN is an effective method for the treatment of “difficult for nailing” tibial fractures. Future multi-centered studies with a larger number of patients are needed to validate our results. 相似文献86.
87.
European Child & Adolescent Psychiatry - 相似文献
88.
Federico Giuseppe Usuelli Cristian Indino Camilla Maccario Luigi Manzi Federico Maria Liuni Ettore Vulcano 《Foot and Ankle Surgery》2019,25(1):19-23
Background
Total ankle replacement (TAR) represents an alternative to fusion for the treatment of end-stage ankle osteoarthritis. The aim of the present study was to retrospectively assess the frequency of infections between TARs with anterior and lateral transfibular approach at 12-months follow-up.Methods
81 TARs through an anterior approach and 69 TARs through a lateral approach were performed between May 2011 and July 2015. We compared surgical time and tourniquet time, as well as superficial and deep infections frequency during the first 12 postoperative months.Results
In the anterior approach group, there were 3 (3.7%) deep infections and 4 (4.9%) superficial wound infections. In the lateral approach group, there were 1 (1.4%) deep infection and 2 superficial wound infections (2.9%). There were not statistically significant differences between the groups. There was a significant difference between anterior approach (115 minutes) and lateral approach group (179 minutes) in terms of surgical time (P < 0.001).Conclusions
The frequency of superficial and deep periprosthetic infections during the first postoperative year was not significantly different in the lateral approach group compared to the anterior approach group, despite the significantly longer surgical time in the lateral transfibular approach group. 相似文献89.
90.
Maria C. Chammas Andre C. Oliveira Mario J. D´Ávilla Pedro H. Moraes Marcelo Straus Takahashi 《Ultrasound in medicine & biology》2019,45(1):50-55
We prospectively evaluated the effectiveness of contrast-enhanced ultrasonography (CEUS) for differentiation of benign versus malignant portal vein thrombosis (PVT). We studied a total of 43 patients with chronic liver disease, hepatocellular carcinoma-suggestive nodules and confirmed PVT, in whom the nature of the PVT was confirmed by follow-up imaging (US, computed tomography and/or magnetic resonance imaging) performed up to 6 mo after CEUS. PVT was assessed by US, Doppler US and CEUS with respect to vessel wall disruption and/or invasion, color Doppler vascularization, pulsed Doppler vascularization pattern and CEUS enhancement and vascularization pattern, and thrombi were classified as benign or malignant based on these findings. Follow-up studies revealed malignant PVT in 22 of the 43 patients (51%) and benign PVT in 21 patients (49%). CEUS findings were consistent with follow-up studies in 41 of the 43 patients (95%), with κ?=?0.903 (p < 0.0001), sensitivity?=?91% and specificity?=?100%, indicating that CEUS can be confidently used to differentiate benign from malignant portal vein thrombosis in the setting of chronic liver disease. 相似文献