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991.
Reproduction of healthy wrist biomechanics should minimize the abnormal joint forces that could potentially result in the failure of a total wrist arthroplasty (TWA). To date, the in vivo kinematics of TWA have not been measured and it is unknown if TWA preserves healthy wrist kinematics. Therefore, the purpose of this in vivo study was to determine the center of rotation (COR) for a current TWA design and to compare its location to the healthy wrist. The wrist COR for six patients with TWA and 10 healthy subjects were calculated using biplane videoradiography as the subjects performed various range-of-motion and functional tasks that included coupled wrist motions. An open-source registration software, Autoscoper, was used for model-based tracking and kinematics analysis. It was demonstrated that the COR was located near the centers of curvatures of the carpal component for the anatomical motions of flexion-extension and radial-ulnar deviation. When compared to healthy wrists, the COR of TWAs was located more distal in both pure radial deviation (P < .0001) and pure ulnar deviation (P = .07), while there was no difference in its location in pure flexion or extension (P = .99). Across all coupled motions, the TWA's COR shifted more than two times that of the healthy wrists in the proximal-distal direction (17.1 vs 7.2 mm). We postulate that the mismatch in the COR location and behavior may be associated with increased loading of the TWA components, leading to an increase in the risk of component and/or interface failure.  相似文献   
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Groin wound infections pose a major problem in vascular surgery. Closed‐incision negative pressure therapy (ciNPT) was especially designed for the management of incisions at risk of surgical site infections. The aim of this study was to investigate whether ciNPT is able to reduce the incidence of wound infections after vascular surgery. Data on 132 consecutive patients, scheduled for vascular surgery with a longitudinal femoral cutdown, were collected prospectively. All patients were randomised either to the ciNPT group (n = 64) or the control group (n = 68) with conventional dressing. In the ciNPT group, the foam dressing was applied intraoperatively and removed after 5 days. The control group received an absorbent dressing. All wounds were evaluated after 5 and 42 days. Infections were graded according the Szilagyi classification (I–III°). There were no significant differences between both groups considering patient characteristics. Indications for surgery were peripheral arterial disease in 95% (125/132) and aneurysm in 5% (7/132). The overall infection rates were 14% (9/64) in the ciNPT group and 28% (19/68) in the control group (P = 0·055). Early infections were observed in 6% (4/64) of the ciNPT group and 15% (10/68) of the control group (P = 0·125). ciNPT did not reduce infection rates associated with different risk factors for infection. While the experiences with the ciNPT device were encouraging, the study fails to provide evidence of the efficacy of the device to reduce groin wound infections after vascular surgery. It illustrates far more that larger multicentre studies are required and appear promising to provide further evidence for the use of ciNPT.  相似文献   
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Background

Controlled space closure in cases of isolated lower second premolar aplasia (ILSPA) without maxillary counterbalancing extraction is challenging. Anterior anchorage loss may occur during space closure resulting in compromised occlusal results in terms of an absence of proper canine guidance during laterotrusive mandible movements.In order to evaluate the effectiveness of Herbst telescope anchorage in combination with double-cable, pull mechanics and a completely customized lingual appliance for orthodontic space management in cases of ILSPA, we tested the null hypothesis that there is a significant deterioration in the sagittal canine relationship towards an Angle-Class-II occlusion expressed as a loss of anterior anchorage following space closure with molar mesialization.

Methods

Twenty-five consecutively de-bonded subjects (female / male 17 / 8; aged at T0 (start of MB Tx) 12.3 to 20.6 years; mean age 15.0 / SD 1.7 years) were included in this retrospective analysis using the inclusion criteria of least of one lower second premolar aplasia; completed treatment with a totally customized lingual appliance (CCLA) in combination with Herbst telescopes. Exclusion criteria were the absence of counterbalancing maxillary extractions, as well as additional tooth aplasia other than lower second premolars. A total of 33 single, lower premolar aplasia space closures (right / left sided 17 / 16) were assessed using plaster casts and intra-oral photographs scaled to the plaster casts, at bonding (T0), Herbst insertion (T1), following gap closure (T2) and de-bonding (T3). Parallelism of roots was controlled by panoramic x-rays at T3.

Results

The mean aplasia space at T0 was 7.5 mm (SD 2.6). Complete space closure was achieved in all 33 situations. The null hypothesis was rejected. There was a significant improvement in the initial canine relationships (mean 3.5 mm distal occlusion at T0) to a mean 0.1 mm at T3. When evaluated against the individual treatment plan, the following amounts of planned improvements were achieved: space closure 100%, canine relationship 97.5%, overjet 93.9%, overbite 96.4%, parallel roots in space closure site 93.9%.

Conclusion

Herbst telescope anchorage in combination with double-cable pull mechanics and a CCLA for orthodontic space closure can deliver predictable, high-quality treatment results.
  相似文献   
997.
Infected nonunion of long bones may require intravenous antibiotics over a lengthy period which may result in a high rate of complications. This study aims to assess the efficacy of local antibiotics used as a replacement to prolonged intravenous therapy. Thirteen patients with infected nonunion of long bones who failed at least one previous surgery were included. The infection was treated through extensive debridement, application of antibiotic-impregnated calcium sulphate pellets and the bone stabilized with external fixation. These patients were monitored for union and infection by clinical signs, laboratory values, and radiographs over a period of 24 months. The results support an eradication of infection and union in all patients with no antibiotic-associated complications. Local antibiotic delivery using calcium sulphate pellets provides an effective method for treatment of nonunion in long bones and is free of the complications from the intravenous route.  相似文献   
998.
We present preliminary results of a case series on refractory bladder neck contracture (BNC) treated with robot-assisted laparoscopic Y-V plasty (RAYV). Between 01/2013 and 02/2016, 12 consecutive adult male patients underwent RAYV in our hospital. BNC developed after transurethral procedures (n = 9), simple prostatectomy (n = 2) and HIFU therapy of the prostate (n = 1). Each patient had had multiple unsuccessful previous endoscopic treatments. All RAYV procedures were performed using a transperitoneal six-port approach (four-arm robotic setting). There were no intraoperative or major postoperative complications. During a median follow-up of 23.2 months two cases of refractory BNC were observed. In both cases a postoperative International Prostate Symptom Score (IPSS) of 20 and 25 was reported, respectively. In contrast, amongst the patients without evidence of refractory BNC the median IPSS was 6.5 reflecting an only mildly impaired voiding function in most cases, thus, suggesting a treatment success in 83.3% of patients. To the best of our knowledge, this is the first report on RAYV for refractory BNC. In our series RAYV was feasible in all patients, and only two cases of refractory BNC were reported during a median follow-up of almost 2 years. At the same time, no intraoperative or major postoperative complications were observed. More clinical data with a longer follow-up are needed in this promising field to reveal the actual efficacy and relevance of RAYV.  相似文献   
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