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991.
Cervical spondylolysis is a rare condition defined as a corticated cleft at the pars interarticularis in the cervical spine. This is the case of C2 spondylolysis demonstrating progressive significant instability, which was successfully treated by anterior cervical discectomy and fusion (ACDF) with cervical anterior plate. We describe a 20-year-old female with C2 spondylolysis presenting with progressive worsening of neck pain associated with progressive instability at the C2/3 segment. The progression of instability was well-documented on flexion-extension cervical spine x-rays. She was successfully treated by C2/3 ACDF with anterior cervical plate. Her preoperative significant neck pain resolved immediately after the surgical intervention. She was completely free from neurological symptoms at 1-year postoperative follow-up. We also review the literature and discuss 24 reported cases with C2 spondylolysis. When planning treatment, we should make sure to differentiate this pathology from acute traumatic fracture, which is a hangman''s fracture. Assessment of C2/3 instability associated with neurological deficits is extremely important to consider management properly. C2/3 ACDF with cervical plate is biomechanically viable, less invasive, and provides adequate surgical stabilization for unstable C2 spondylolysis.  相似文献   
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Blunt cerebrovascular injury (BCVI) is known to be a potentially fatal complication of cervical spine injury (CSI). Methods for screening the appropriate population remain to be elucidated, especially in Japan. This retrospective study was conducted to predict the risk factors relevant to BCVIs. Among 92 patients with CSI transferred to our institution from April 2007 to March 2012, 40 patients (35 men, 5 women) with neurological deficits and/or significant cervical spine fracture including fracture of transversarium, facet, body, lamina, and spinous process, underwent multi-detector computed tomography angiography (MDCTA) and magnetic resonance angiography (MRA), which identified 10 patients with BCVI [2 carotid artery injuries (BCAIs) and 9 vertebral artery injuries (BVAIs); 1 patient suffered both]. Univariate analyses exploring associations between individual risk factors and BCVI and BVAI were performed using Fisher''s exact test and Chi-square test for dichotomous variables and the unpaired t-test for continuous variables. Multiple logistic regression analyses for BCVI and BVAI were carried out using stepwise methods. On univariate and multivariate analysis, hyperextension injury was significantly associated with BVAI (p = 0.01 and p = 0.02), and subluxation (dislocation of vertebral body > 5 mm) was a significant predictor of BCVI (p = 0.04 and p = 0.03) and BVAI (p = 0.01 and p = 0.01). Prompt evaluation for BCVIs is recommended in CSI patients with hyperextension injury and dislocation of the vertebral body.  相似文献   
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IntroductionDislocation following total hip replacement continues to be a problem for which no completely satisfactory solution has been found. Several methods have been proposed to reduce the incidence of hip dislocations with varying degrees of success, including elevated rim liners, constrained liners and large diameter bearings. We present our experience with the double mobility acetabular component in patients at high risk of instability.MethodsThis was a retrospective review of 65 primary total hip arthroplasties in 55 patients (15 men, 40 women), performed between October 2005 and November 2009. The majority (80%) of patients had at least two and 26% had at least three risk factors for instability. The mean age was 76 years (range: 44–92 years). The patients were followed up for a mean duration of 60 months (range: 36–85 months).ResultsFourteen patients died and one was lost to follow-up, leaving fifty hips for final assessment. Until the final follow-up appointment, no patients had dislocation and none required revision surgery. The mean Oxford hip score improved from 45.0 to 26.5 (p<0.0001). The mean Merle d’Aubigné pain score improved from 1.4 to 4.9 (p<0.0001), the walking score from 2.3 to 3.1 (p<0.07) and the absolute hip function score from 5.4 to 10.8 (p<0.0001). There were no clinical or radiographic signs of loosening.ConclusionsThe double mobility acetabular component was successful at preventing dislocation during early to medium-term follow-up. However, as data are still lacking with regard to polyethylene wear rates at the additional bearing surface, it would be prudent to restrict the use of this implant to selected patients at high risk of instability.  相似文献   
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Context

The role of adjuvant chemotherapy (AC) or neoadjuvant chemotherapy (NC) remains poorly defined for the management of upper tract urothelial carcinoma (UTUC), although some studies suggest a benefit.

Objective

To update the current evidence on the role of NC and AC for UTUC patients.

Evidence acquisition

We searched for all studies investigating NC or AC for UTUC in Medline, Embase, the Cochrane Central Register of Controlled Trials, and abstracts from the American Society of Clinical Oncology meetings prior to February 2014. A systematic review and meta-analysis were performed.

Evidence synthesis

No randomized trials investigated the role of AC for UTUC. There was one prospective study (n = 36) investigating adjuvant carboplatin–paclitaxel and nine retrospective studies, with a total of 482 patients receiving cisplatin-based or non-cisplatin–based AC after nephroureterectomy (NU) and 1300 patients receiving NU alone. Across three cisplatin-based studies, the pooled hazard ratio (HR) for overall survival (OS) was 0.43 (95% confidence interval [CI], 0.21–0.89; p = 0.023) compared with those who received surgery alone. For disease-free survival (DFS), the pooled HR across two studies was 0.49 (95% CI, 0.24–0.99; p = 0.048). Benefit was not seen for non-cisplatin–based regimens. For NC, two phase 2 trials demonstrated favorable pathologic downstaging rates, with 3-yr OS and disease-specific survival (DSS) ≤93%. Across two retrospective studies investigating NC, there was a DSS benefit, with a pooled HR of 0.41 (95% CI, 0.22–0.76; p = 0.005).

Conclusions

There appears to be an OS and DFS benefit for cisplatin-based AC in UTUC. This evidence is limited by the retrospective nature of studies and their relatively small sample size. NC appears to be promising, but more trials are needed to confirm its utility.

Patient summary

After a comprehensive search of studies examining the role of chemotherapy for upper tract urothelial cancer, the pooled evidence shows that cisplatin-based adjuvant chemotherapy was beneficial for prolonging survival.  相似文献   
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