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91.
Serkan Simsek Kazim Yigitkanli Hakan Seçkin Ayhan Comert Halil I. Acar Deniz Belen Ibrahim Tekdemir Alaittin Elhan 《European spine journal》2009,18(9):1321-1325
Although various posterior insertion angles for screw insertion have been proposed for C1 lateral mass, substantial conclusions
have not been reached regarding ideal angles and average length of the screw yet. We aimed to re-consider the morphometry
and the ideal trajections of the C1 screw. Morphometric analysis was performed on 40 Turkish dried atlas vertebrae obtained
from the Department of Anatomy at the Medical School of Ankara University. The quantitative anatomy of the screw entry zone,
trajectories, and the ideal lengths of the screws were calculated to evaluate the feasibility of posterior screw fixation
of the lateral mass of the atlas. The entry point into the lateral mass of the atlas is the intersection of the posterior
arch and the C1 lateral mass. The optimum medial angle is 13.5 ± 1.9° and maximal angle of medialization is 29.4 ± 3.0°. The
ideal cephalic angle is 15.2 ± 2.6°, and the maximum cephalic angle is 29.6 ± 2.6°. The optimum screw length was found to
be 19.59 ± 2.20 mm. With more than 30° of medial trajections and cephalic trajections the screw penetrates into the spinal
canal and atlantooccipital joint, respectively. Strikingly, in 52% of our specimens, the height of the inferior articular
process was under 3.5 mm, and in 70% was under 4 mm, which increases the importance of the preparation of the screw entry
site. For accommodation of screws of 3.5-mm in diameter, the starting point should be taken as the insertion of the posterior
arch at the superior end of the inferior articular process with a cephalic trajection. This study may aid many surgeons in
their attempts to place C1 lateral mass screws. 相似文献
92.
Ali Chamseddine Roger Jawish Houssam Hamdan Hadi Zein Assad Taha 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2009,19(2):87-92
We report a case of acute traumatic posterior shoulder dislocation in a 41-year-old patient, which we treated surgically by
a modification of the procedure described by Gerber for humeral head reconstruction in such cases. The diagnosis was confirmed
by CT scan, which also helped us to assess the size of the antero-medial humeral head defect or impaction secondary to the
dislocation; the size of this defect being a determinant element for the indication. Because the shoulder was unstable after
closed reduction and almost 50% of the humeral head was impacted, we carried out a surgical treatment using an original technique
as mentioned above. Radiologic and surgical features of acute traumatic posterior shoulder dislocation are discussed with
special emphasis on diagnosis, indications and surgical aspects of this rare lesion, which represent 2–4% of acute traumatic
shoulder dislocations. 相似文献
93.
Mehmet Dadaci Bilsev Ince Zeynep Altuntas Ozan Bitik Haldun Onuralp Kamburoglu Hakan Uzun 《Indian Journal of Orthopaedics》2016,50(4):384-389
Background:The fingertip is the most frequently injured and amputated segment of the hand. There are controversies about defining clear indications for microsurgical replantation. Many classification systems have been proposed to solve this problem. No previous study has simultaneously correlated different classification systems with replant survival rate. The aim of the study is to compare the outcomes of fingertip replantations according to Tamai and Yamano classifications.Results:Of the 34 fingertips, 26 (76.4%) survived. Ten (66.6%) of 15 digits replanted in Tamai zone 1 and 16 (84.2%) of 19 digits replanted in Tamai zone 2 survived. There were no replantation failures in Yamano type 1 injuries (100%) and only two failed in Yamano type 2 (75%). Replantation was successful in 14 of 20 Yamano type 3 injuries, but six failed (70%). The percentage of success rates was the least in the hybridized groups of Tamai zone 1-Yamano type 2 and Tamai zone 1-Yamano type 3. Although clinically distinct, the survival rates between the groups were not statistically significantly different.Conclusions:The level and mechanism of injury play a decisive role in the success of fingertip replantation. Success rate increases in proximal fingertip amputations without crush injury. 相似文献
94.
Acquired non-traumatic frontal sinus encephaloceles are very rare lesions that are usually caused by a tumour or hydrocephalus.
We present a 31-year-old woman with a frontal sinus encephalocele who developed rhinorrhoea after a ventriculo-peritoneal
shunt to treat her hydrocephalus and underwent radiotherapy for a tectum tumour. 相似文献
95.
Injuries after an electric shock, such as dermal burns, motor and sensory nerve deficits, fractures and dislocations, are
reported in the literature. Posterior dislocation of the shoulder after electric-shock is the common musculoskeletal injury.
Bilateral dislocation, either anterior or posterior, is rarely seen and reported. We report a case of bilateral shoulder fracture
dislocation in opposite directions following an electric-shock and discuss the mechanism, the diagnosis and the treatment. 相似文献
96.
Aydin H Young RH Ronnett BM Epstein JI 《The American journal of surgical pathology》2005,29(4):520-523
Clear cell papillary cystadenoma is a rare epithelial tumor of the epididymis, which may present as an isolated lesion or as a component of von Hippel-Lindau disease (VHLD). Recently, tumors have also been described in the female genital tract with similar histology. Recognition of clear cell papillary cystadenoma is critical because of its association with VHLD and its potential diagnostic confusion with metastatic renal cell carcinoma because of a shared architecture and clear cells. In this study, we report on the immunohistochemical differentiation of 5 clear cell papillary cystadenomas, 3 of the epididymis and 2 of the mesosalpinx, from metastatic renal cell carcinoma. In 2 cases, there was a history of renal cell carcinoma in the setting of VHLD; and in 1 of these cases, an epididymal papillary cystadenoma was initially considered to be metastatic renal cell carcinoma. Immunohistochemically, tumor cells were moderately intensely positive for cytokeratin AE1/AE3 and epithelial membrane antigen, strongly positive for CK7 and negative for CK20 and RCC. Four of 5 cases were negative for CD10. This staining profile contrasts with that reported for clear cell renal cell carcinomas, which are typically negative for CK7 and immunoreactive for renal cell carcinoma (RCC) and CD10. Our findings indicate that, in cases where there is uncertainty about the histologic diagnosis of clear cell papillary cystadenoma, the above immunohistochemical panel helps to rule out metastatic renal cell carcinoma. 相似文献
97.
BACKGROUND: The Centers for Disease Control and Prevention (CDC) recommends hepatitis B virus (HBV) immunization for all hemodialysis (HD) patients because they are at high risk of infection. Several studies have shown that the development of protective antibody titers after HBV vaccination is much lower in HD patients. We hypothesized that human immunodeficiency virus (HIV) infection in patients with end-stage renal disease (ESRD) would further impair the immune response to hepatitis B vaccination. METHODS: We performed a retrospective cohort study of patients undergoing long-term hemodialysis from 1990 to 2002 at the United States-based dialysis facilities of Gambro Corporation, North America. The response rate defined as an increase in anti-HBs levels >/=10 mIU/L after a month of the third dose of HBV vaccination was determined in HIV-infected and a randomly selected group of ESRD patients. The demographic information, laboratory data, and hepatitis B surface antibody (anti-HBs) titers were recorded from the Gambro Corporation database on these patients. RESULTS: Of the 347 adult HIV ESRD patients, 116 received three doses of recombinant hepatitis B vaccination. Seventy percent were male, and the majority (86%) were black. Of the 116 patients who received three doses of HBV vaccination, 62 (53.4%) developed protective antibody titers. This was comparable to the response rate of 50.4% in the randomly selected 220 non-HIV hemodialysis patients. Among HIV ESRD patients, the mean hemoglobin (Hgb) was higher in patients who developed protective antibody titers (Hgb 11.61 +/- 2 vs. 10.55 +/- 1.86, P value <0.01). On multivariate logistic regression analysis, higher Hgb was associated with protective antibody titers (odds ratio: 1.34, 95% CI 0.99-1.72). Seventy percent of the HIV-infected responders maintained protective antibody titers 6 months after vaccination. CONCLUSION: Hepatitis B vaccination should be offered to all HIV-infected ESRD patients because over half of the patients with HIV and ESRD can develop protective antibodies. 相似文献
98.
Bulut F Dervisoglu A Kesim M Guven H Polat C 《Journal of laparoendoscopic & advanced surgical techniques. Part A》2005,15(2):112-120
BACKGROUND: Laparoscopic surgical interventions are being used in trauma patients for diagnostic and therapeutic purposes, but there are limited studies on this subject. The effect of pneumoperitoneum during intra-abdominal hemorrhage has not been elucidated. The aim of this study was to investigate the hemodynamic, respiratory, and renal effects of pneumoperitoneum in the splenic injury/ hemorrhagic shock model in rats. MATERIAL AND METHODS: In this study, 80 anesthetized Wistar male rats (294.5 +/- 31.2 g) were randomized into 2 main groups: nontraumatized (group A) and traumatized (group B). After initial preparation and monitoring, each group was divided according to the degree of pneumoperitoneum. The nontraumatized subgroups were A1, sham-operated; A2, 4-8 mm Hg; A3, 9-13 mm Hg; and A4, 14-18 mm Hg. The traumatized subgroups were B1, splenic injury without pneumoperitoneum; B2, B3, and B4, splenic injury with pneumoperitoneum at 4-8 mm Hg, 9-13 mm Hg, and 14-18 mm Hg, respectively. Mean arterial pressure, heart rate, and respiratory rate were monitored continuously. Blood samples were obtained for hemoglobin, hematocrit, arterial blood gases, and biochemical analyses. Twenty-four hour urine output was collected. RESULTS: In group B4, pH, pCO2, and HCO3 levels were lower than in all other groups, while pCO2 and base deficit levels were significantly higher (P < 0.05). Both blood and urine analysis results showed that 24-hour urine output and the glomerular filtration rate of groups A4 and B4 were significantly lower (P < 0.05), while urinary osmolarity and fractional sodium excretion levels were significantly higher (P < 0.05). CONCLUSION: High-pressure pneumoperitoneum in splenically traumatized rats amplifies acidosis, decreases urine output, decreases glomerular filtration rate, and increases urinary osmolarity and fractional sodium excretion significantly. 相似文献
99.
Söyüncü Y Yildirim FB Sekban H Ozdemir H Akyildiz F Sindel M 《Journal of spinal disorders & techniques》2005,18(3):243-246
OBJECTIVE: Transpedicular spinal fixation has recently been the focus of increased attention in several institutions throughout the world, but its safety and efficacy are still important questions for orthopedic surgeons. Accurate screwing through the pedicle will avoid neurologic complications and increase the stability of the instrumentation. In this study, it was aimed to analyze the anatomic relations quantitatively between the lumbar pedicle and the adjacent dural sac and nerve roots, to determine the risky areas for neural injury during transpedicular screw placement. METHODS: Ten adult cadavers were used for observation of the lumbar pedicle and its relations. After removal of the laminas and facets, the lumbar pedicles, dural sac, and nerve roots were exposed. Interpedicular distance (IPD), pedicle-inferior nerve root distance (PIRD), pedicle-superior nerve root distance (PSRD), and pedicle-dural sac distance (PDSD) were measured. RESULTS: Average distance from the lumbar pedicle to the dural sac medially and to the adjacent nerve roots superiorly and inferiorly through the cranial to caudal lumbar levels ranged from 1.29 to 1.56, from 4.12 to 5.52, and from 1.10 to 1.06 mm, respectively. The mean IPD ranged from 32.77 to 41.24 mm. There were statistically significant differences between the L5 level and other lumbar levels for IPD, PSRD, and PDSD measurements. CONCLUSIONS: These results indicate that although L5 is safer than other lumbar levels for pedicle screw insertion, an improper medial and caudal placement of a pedicular screw will carry a great risk of injury to the dural sac and inferior nerve root. 相似文献
100.
Nafiye Yılmaz Banu Seven Hakan Timur Ayçağ Yorgancı Hasan Ali İnal Müberra Namlı Kalem Ziya Kalem Özge Han Banu Bilezikçi 《Journal of the Chinese Medical Association》2018,81(10):905-911