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991.
INTRODUCTION: This study focused on the change in the range of motion (ROM) during the perioperative period, i.e., the preoperative and intraoperative ROM, and that on discharge, and compared the difference between posterior cruciate ligament-retaining (PCLR) and -sacrificing (PCLS) prostheses. MATERIALS AND METHODS: In this prospectively randomized study, we compared the changes in the ROM in PCLR (n = 50) and PCLS (n = 50) total knee arthroplasties. RESULTS: The mean flexion in PCLR prostheses was 130.0 degrees preoperatively, 120.0 degrees intraoperatively, and 105.0 degrees at discharge, and 125.0 degrees , 120.0 degrees , and 100.0 degrees , respectively, in PCLS. The designs did not differ statistically in each period (P > 0.05). Both designs showed significant correlations between the preoperative and intraoperative ROM, and between the preoperative and discharge ROM. Only the PCLS showed a significant correlation between the intraoperative and discharge ROM, and a significant difference was observed in correlation of rank coefficient between the two prostheses (P < 0.001). CONCLUSIONS: The PCLS design has an advantage in rehabilitation planning because of the predictable changes in the ROM during the perioperative period, although the acquired average ROM at discharge did not differ statistically.  相似文献   
992.
OBJECTIVES: The aim of this study was to compare the radiological outcome of open and close reduction and osteosynthesis methods in the treatment of type II and III supracondylar humerus fractures in childhood with respect to the immediate post-operative reduction quality in sagittal plane. METHOD: One hundred and forty four-pediatric patients with type IIb and III supracondylar humerus fractures treated at two centers between 1995 and 2005 were evaluated radiologically within a retrospective study. Seventy-six patients (54 boys, 22 girls, mean age 7.6, range 2-12) were treated by closed reduction and cross percutaneous pinning while 68 (49 boys, 19 girls, mean age 7.3, range 2-13) were treated by open reduction. The reduction quality of the open and closed groups was compared on immediate post-operative lateral radiographs by measuring of lateral humerocapitellar angle, anterior humeral line and anterior coronoid line criteria. The reduction quality was classified excellent, good, fair and poor according to the achievement of three, two, one or none of the criteria, respectively. Reductions classified as excellent and good were introduced as acceptable results. RESULTS: At least one criterion was achieved in all the patients of both the groups. The mean humerocapitellar angle was 30.1 degrees in closed reduction group while the mean of it was 29.8 degrees in open reduced group. Radiograph of 48 (63.1%) patients with closed reduction were found to display the anterior humeral line intersecting the middle one-third of capitellum while this criteria was 45 (66%) in open reduction group. The anterior coronoid line was disturbed in three patients in each of both the groups. The reduction quality was evaluated to be excellent in 32 patients, good in 31, fair in 13 at the closed reduction group while these evaluations were 31, 20 and 17 in open reduction group, respectively. Successful reduction was achieved in 74.9% of the patients in closed reduction group and 75% of the patients in open reduction group. CONCLUSION: It is concluded that there was no significant difference between closed and open reductions of pediatric displaced supracondylar fractures with regard to the radiological criteria of reduction quality in sagittal plane.  相似文献   
993.
BACKGROUND: The Roux-en-Y gastric bypass procedure (RYGBP) is in many countries the gold standard for obtaining long-lasting weight reduction and improvement of obesity-related comorbidities. However, performing this operation by standard laparoscopic techniques requires important surgical skills because of the anastomoses involved. The da Vinci surgical robot system with its enhanced degrees of freedom in motion and three-dimensional vision is designed to overcome the difficulties encountered in traditional laparoscopic surgery with suturing and delicate tissue handling. METHODS: For this study, 45 patients (9 men) with a mean body mass index (BMI) of 44.2 (range, 35.1-55.4) underwent RYGBP with the aid of the da Vinci robot system. They were compared with 45 consecutive patients with a mean BMI of 43.9 (range, 35.1-56.2) who underwent a laparoscopic RYGBP by the same surgeon during the same period. RESULTS: Overall, the total operating time was shorter for the laparoscopic cases (127 vs 212 min; p < 0.05). However, the last 10 robotic cases were performed in the same time span as the laparoscopic cases (136 vs 127 min). The total robotic setup time remained constant at about 30 min. There were no differences in postoperative complications between the two groups in terms of anastomotic leakage or stenosis. In the robotic group, more conversions to open surgery were noted. Early in the study, four patients (9%) had to undergo conversion to standard laparoscopic techniques due to inadequate setup of the robotic arms. Five patients (11%), however, had to undergo conversion to open surgery because of intestinal laceration during manipulation of the intestines with the robotic instruments. The costs were higher for robotic surgery than for standard laparoscopic RYGBP, mainly because of the extra equipment used, such as ultrasonic devices. CONCLUSION: The RYGBP procedure can be performed safely with the da Vinci robot after a learning curve of about 35 cases. At this writing, however, it is not clear whether the da Vinci system offers a real advantage over standard laparoscopic techniques.  相似文献   
994.
Shimon I  Cohen ZR  Ram Z  Hadani M 《Neurosurgery》2001,48(6):1239-43; discussion 1244-5
OBJECTIVE: Transsphenoidal surgery is the preferred treatment modality for growth hormone (GH)-secreting pituitary adenomas. In many series, the reported postoperative remission is based mainly on achievement of GH levels less than 2 ng/ml. Strict criteria for insulin-like growth factor I normalization and even lower GH levels (<1 ng/ml) are now suggested to define cure of acromegaly, but the evidence does not yet support such low GH levels in epidemiological follow-up. We analyzed our postoperative results in a large cohort of patients with acromegaly. METHODS: Ninety-eight patients harboring GH-secreting adenomas (46 microadenomas and 52 macroadenomas) underwent transsphenoidal surgery between 1990 and 1999. Ninety-one patients were operated for the first time, and 12 patients underwent reoperations because of previous surgical failure (7 had undergone surgery elsewhere previously). Biochemical remission was defined as a repeated fasting or glucose-suppressed GH level of 2 ng/ml or less, and a normal insulin-like growth factor I level. RESULTS: Remission was achieved in 74% of all patients after one operation, including 84% of patients with microadenomas and 64% of patients with macroadenomas. Seventy-three percent of patients with macroadenomas 11 to 20 mm in size achieved remission, as compared with a 20% remission rate for patients with adenomas larger than 20 mm. Patients with preoperative random GH levels lower than 50 ng/ml had a better outcome (85% remission), whereas GH greater than 50 ng/ml was associated with remission in 30% of the patients. Only one of the patients (8%) with postoperative active disease who underwent a second operation achieved remission. Recurrence was rare (one patient), and all failed surgical attempts could be detected during the immediate postoperative evaluation. CONCLUSION: On the basis of strict postoperative GH and insulin-like growth factor I criteria to define remission, our series demonstrates the efficacy of transsphenoidal surgery for acromegalic patients with microadenomas and noninvasive macroadenomas. However, patients with large adenomas (>20 mm) and preoperative GH greater than 50 ng/ml have a poor prognosis and require adjunctive medical or radiation therapy to control GH hypersecretion.  相似文献   
995.
Although several effective therapeutic options are available for bleeding from portal hypertension, surgery has a well-defined role in the management of patients with good liver function who are electively operated. The aim of this investigation was to evaluate the operative mortality and morbidity of portal blood flow-preserving procedures in a highly select patient population. The records of 148 patients operated on between 1996 and 2000 using one of two techniques (selective shunts or a Sugiura-Futagawa operation [complete portoazygos disconnection]) were analyzed with particular attention to operative mortality, postoperative rebleeding, and encephalopathy. Survival was calculated according to the Kaplan-Meier method. Sixty-one patients had distal splenorenal shunts placed, and 87 patients had a devascularization procedure. Operative mortality for the group as a whole was 1.2%. In the group with selective shunts, the rebleeding rate was 4.9%, the encephalopathy rate was 9.8%, and the shunt obstruction rate was 1.6%. Survival at 24 months was 94% and at 48 months was 92%. In those undergoing devascularization, the encephalopathy rate was 5% and the rebleeding rate was 14%. Survival at 24 months was 90% and at 48 months was 86%. Portal blood flow-preserving procedures have very low morbidity and mortality rates at specialized centers. In addition, a low rebleeding rate is associated with a good quality of life. Low-risk patients with bleeding portal hypertension should be considered for surgical treatment.  相似文献   
996.
Hadani M  Spiegelman R  Feldman Z  Berkenstadt H  Ram Z 《Neurosurgery》2001,48(4):799-807; discussion 807-9
OBJECTIVE: Preliminary clinical experience with a novel, compact, intraoperative magnetic resonance imaging (MRI)-guided system that can be used in an ordinary operating room is presented. DESCRIPTION OF INSTRUMENTATION: The system features an MRI scanner integrated with an optical and MRI tracking system. Scanning and navigation, which are operated by the surgeon, are controlled by an in-room computer workstation with a liquid crystal display screen. The scanner includes a 0.12-T permanent magnet with a 25-cm vertical gap, accommodating the patient's head. The field of view is 11 x 16 cm, encompassing the surgical area of interest. The magnet is mounted on a transportable gantry that can be positioned under the surgical table when not in use for scanning, thus rendering the surgical environment unmodified and allowing the use of standard instruments. The features of the integrated navigation system allow flap planning and intraoperative tracking based on updated images acquired during surgery. OPERATIVE TECHNIQUE: Twenty patients with brain tumors were surgically treated using craniotomy or trans-sphenoidal approaches. One patient underwent conscious craniotomy with cortical mapping, and two underwent electrocorticography. EXPERIENCE AND RESULTS: Planning was accurate. Resection control images were obtained for all patients during surgery, with precise localization of residual tumor tissue. There were no surgical complications related to the use of the system. CONCLUSION: This intraoperative MRI system can function in a normal operating room modified only to eliminate radiofrequency interference. The operative environment is normal, and standard instruments can be used. The scanning and navigation capabilities of the system eliminate the inaccuracies that may result from brain shift. This novel type of intraoperative MRI system represents another step toward the introduction of the modality as a standard method in neurosurgery.  相似文献   
997.
BACKGROUND: Use of the inferior mesenteric vein (IMV) for partial portal decompression has not been recommended as a first-line option for intractable gastroesophageal variceal bleeding because of the thin diameter of the vein. Although these indications remain relevant, few reports have compared partial portal decompression using the IMV with other therapies. We propose that partial portal decompression using the IMV is a useful alternative treatment for intractable variceal bleeding. METHODS: We performed partial portal decompression using the IMV in eight patients with intractable variceal bleeding that had been uncontrolled using medical and endoscopic therapies. All patients were classified into Child's class B or C. The surgical data, morbidity, and mortality were assessed. RESULTS: Mean portal venous pressure significantly decreased from 26.9 +/- 2.0 mmHg before the surgery to 19.8 +/- 3.9 mmHg after the surgery. The operative mortality rate was 0%. The mean duration of hospital stay was 25.5 +/- 13.3 days. Although one patient experienced recurrent bleeding, shunt patency was well maintained in all patients during the follow-up period (mean 28.9 +/- 14.1 months). Six patients are still alive and well without ascites or hepatic encephalopathy. Two of the Child's class C patients who underwent emergency shunt died owing to hepatic decompensation. CONCLUSION: Partial portal decompression using the IMV can be a safe, effective way to treat intractable variceal bleeding in patients with liver cirrhosis. However, use of the shunt procedure may have the most survival benefits for cirrhotic patients with preserved liver function.  相似文献   
998.

Backround  

Diverticulosis is a common disease in the western society with an incidence of 33–66%. 10–25% of these patients will develop diverticulitis. In order to prevent a high-risk acute operation it is advised to perform elective sigmoid resection after two episodes of diverticulitis in the elderly patient or after one episode in the younger (< 50 years) patient. Open sigmoid resection is still the gold standard, but laparoscopic colon resections seem to have certain advantages over open procedures. On the other hand, a double blind investigation has never been performed. The Sigma-trial is designed to evaluate the presumed advantages of laparoscopic over open sigmoid resections in patients with symptomatic diverticulitis.  相似文献   
999.

Background  

To develop a sensitive and specific screening tool for knee and hip osteoarthritis in the general population of elderly people.  相似文献   
1000.

Background  

Chronic plantar heel pain (CPHP) is one of the most common musculoskeletal disorders of the foot, yet its aetiology is poorly understood. The purpose of this study was to examine the association between CPHP and a number of commonly hypothesised causative factors.  相似文献   
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