The application of a zero-profile implant in anterior cervical discectomy and fusion

We analyzed the clinical efficacy of the Zero-P implant (Synthes GmbH Switzerland, Oberdorf, Switzerland) in the treatment of single level cervical spondylotic myelopathy. The clinical data of 47 patients with single level cervical spondylotic myelopathy were retrospectively analyzed. Twenty-two patients were treated with a Zero-P implant (Group A) and 25 with a titanium plate with cage (Group B) between January 2009 and September 2010. Operative time, intraoperative blood loss, preoperative and postoperative Japanese Orthopaedic Association (JOA) scores and JOA recovery rate, dysphagia incidence and adjacent segment degeneration rate were measured. The mean operative time in Group A and Group B was 98.18 minutes and 105.4 minutes, respectively. The average intraoperative blood loss in Group A and Group B was 87.95 ml and 92.4 ml, respectively. There were no statistical differences in operation time and intraoperative blood loss between the two groups (p > 0.05). The JOA score was significantly improved in the two groups (p < 0.001), and the recovery rate was similar (60.86% for Group A versus 62.95% for Group B, p > 0.05). Dysphagia was experienced by one (4.5%) patient in Group A and eight (32%) patients in Group B, which was significantly different (p = 0.044). There was no statistical significance found in the adjacent level degeneration rates between Group A and Group B (p = 0.330). The Zero-P implant and traditional titanium plate with cage are effective treatments for single level cervical spondylotic myelopathy, but the Zero-P implant has a lower dysphagia incidence.     

Experimental research on the relationship between fit accuracy and fracture resistance of zirconia abutments

Objectives

The purpose of the study was to investigate the correlation between fit accuracy and fracture resistance of zirconia abutments, as well as its feasibility for clinical applications.

Methods

Twenty self-made zirconia abutments were tested with 30 Osstem GSII implants. First, 10 Osstem GSII implants were cut into two parts along the long axis and assembled with the zirconia abutments. The microgaps between the implants and the zirconia abutments were measured under a scanning electron microscope. Second, the zirconia abutments were assembled with 20 un-cut implants and photographed before and after being fixed with a central screw of 30-N cm torque. The dental films were measured by Digora for Windows 2.6 software. Then the fracture resistance of zirconia abutments was measured using the universal testing machine at 90°. All results were analyzed using SPSS13.0 software.

Results

The average internal-hexagon microgaps between the implants and zirconia abutments were 19.38 ± 1.34 μm. The average Morse taper microgap in the implant–abutment interface was 17.55 ± 1.68 μm. The dental film showed that the Morse taper gap in the implant–abutment interface disappeared after being fixed with a central screw of 30-N cm torque, and the average moving distance of the zirconia abutments to the implants was 0.19 ± 0.02 mm. The average fracture resistance of zirconia abutments was 282.93 ± 17.28 N. The internal-hexagon microgap between the implants and zirconia abutments was negatively related to the fracture resistance of the abutments (r₁ = −0.97, p < 0.01). The Morse taper microgap in the implant–abutment interface was negatively related to the fracture resistance of the abutments (r₂ = −0.84, p < 0.01).

Conclusions

The microgap between implant and abutment was negatively related to the fracture resistance of the abutment, while the internal-hexagon microgap has better correlation than the Morse taper microgap. The closure of microgap is helpful to improve the fracture resistance of zirconia abutments. The fracture resistance of zirconia abutments can satisfy the clinical application.     

Temporomandibular disorders among Brazilian adolescents: reliability and validity of a screening questionnaire

Temporomandibular disorders (TMD) screeners assume significant item overlap with the screening questionnaire proposed by the American Academy of Orofacial Pain (AAOP).

Objective

To test the reliability and validity of the Portuguese version of AAOP questions for TMD screening among adolescents.

Material and Methods

Diagnoses from Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I were used as reference standard. Reliability was evaluated by internal consistency (KR-20) and inter-item correlation. Validity was tested by sensitivity, specificity, predictive values, accuracy and receiver operating characteristic (ROC) curves, the relationship between the true-positive rate (sensitivity) and the false-positive rate (specificity). Test-retest reliability of AAOP questions and intra-examiner reproducibility of RDC/TMD Axis I were tested with kappa statistics.

Results

The sample consisted of 1307 Brazilian adolescents (56.8% girls; n=742), with mean age of 12.72 years (12.69 F/12.75 M). According to RDC/TMD, 397 [30.4% (32.7% F/27.3% M)] of adolescents presented TMD, of which 330 [25.2% (27.6% F/22.2% M)] were painful TMD. Because of low consistency, items #8 and #10 of the AAOP questionnaire were excluded. Remaining items (of the long questionnaire version) showed good consistency and validity for three positive responses or more. After logistic regression, items #4, #6, #7 and #9 also showed satisfactory consistency and validity for two or more positive responses (short questionnaire version). Both versions demonstrated excellent specificity (about 90%), but higher sensitivity for detecting painful TMD (78.2%). Better reproducibility was obtained for the short version (k=0.840).

Conclusions

The Portuguese version of AAOP questions showed both good reliability and validity for the screening of TMD among adolescents, especially painful TMD, according to RDC/TMD.     

Duke Activity Status Index for Cardiovascular Diseases: Validation of the Portuguese Translation

Background

The Duke Activity Status Index (DASI) assesses the functional capacity of patients with cardiovascular disease (CVD), but there is no Portuguese version validated for CVD.

Objectives

To translate and adapt cross-culturally the DASI for the Portuguese-Brazil language, and to verify its psychometric properties in the assessment of functional capacity of patients with CVD.

Methods

The DASI was translated into Portuguese, then checked by back-translation into English and evaluated by an expert committee. The pre-test version was first evaluated in 30 subjects. The psychometric properties and correlation with exercise testing was performed in a second group of 67 subjects. An exploratory factor analyses was performed in all 97 subjects to verify the construct validity of the DASI.

Results

The intraclass correlation coefficient for test-retest reliability was 0.87 and for the inter-rater reliability was 0.84. Cronbach''s α for internal consistency was 0.93. The concurrent validity was verified by significant positive correlations of DASI scores with the VO₂max (r = 0.51, p < 0.001). The factor analysis yielded two factors, which explained 54% of the total variance, with factor 1 accounting for 40% of the variance. Application of the DASI required between one and three and a half minutes per patient.

Conclusions

The Brazilian version of the DASI appears to be a valid, reliable, fast and easy to administer tool to assess functional capacity among patients with CVD.     

Pneumomédiastin tardif révélé par un œdème aigu du poumon en hémodialyse

Central venous catheterization occupies an important place in the treatment of end stage renal disease pending the creation of an arteriovenous fistula. However, this procedure is not devoid of complications. We report a case of late pneumomediastinum revealed by an acute pulmonary edema in a young patient on hemodialysis, and we discuss its characteristics.     

转子间骨折内固定术后不稳定的力学分析及相关策略（附96例报告）

目的从力学分析的角度探讨股骨转子间骨折内固定术后不稳定的方式、原因及相关对策。方法对作内固定治疗的96例转子间骨折病例，术后及每6周随访摄片，作力学分析。结果18例术后发生改变，其中2例有明显的髋内翻（颈干角≤110°），2例有旋转内翻改变（颈干角〉110°），14例有股骨颈短缩现象。结论转子间骨折后内固定与骨折区域构建的力学缺陷是术后不稳的主要原因，大转子与小转子的稳定对维护骨折术后的稳定有重要作用，在可能的情况下都应该予以重建，但这不是起唯一决定作用的因素。目前的内固定系统，如果构建合理，在力学上能够替代因复杂骨折所致的力学不稳。因此，最重要的是充分分析和预见每一骨折类型可能出现的力学不稳定而进行合适的固定，制定合理的策略。     

Long-term outcomes of six patients after partial internal biliary diversion for progressive familial intrahepatic cholestasis

Background

Partial internal biliary diversion (PIBD) is an alternative approach for the treatment of devastating pruritus in patients with progressive familial intrahepatic cholestasis (PFIC). In these patients quality of life can be improved and progression of liver disease can be delayed while waiting for liver transplantation. The aim of our study was to evaluate six patients with PFIC who have undergone PIBD in long-term follow-up.

Parathyroidectomy in patients with chronic kidney disease: Impacts of different techniques on the biochemical and clinical evolution of secondary hyperparathyroidism

Background

Parathyroidectomy (PTx) decreases the mortality rate of refractory secondary hyperparathyroidism (rSHP) due to chronic kidney disease. A consensus regarding which techniques of PTx are associated with better outcomes is not available. The aims of this study are to evaluate the clinical and laboratory evolution of 49 hemodialysis patients with rSHP who underwent PTx using different techniques.