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101.
OBJECTIVE: Comparison of the healing process in open osteotomy and closed fracture models that were used to study fracture healing. DESIGN: Randomized, prospective study in experimental animals, with a recovery duration of two and four weeks. SETTING: Unrestricted cage activity with weight bearing as tolerated. ANIMALS: Thirty-four skeletally mature, female New Zealand White rabbits. INTERVENTIONS: Closed fractures and open osteotomies of the tibial diaphysis were reduced and immobilized with four-pin, double-bar external fixators. MAIN OUTCOME MEASUREMENTS: Callus circumference was measured with a tape measure, bridging callus was assessed on biplane radiographs and evaluated histologically, and torsional stiffness and maximum torque were measured. RESULTS: Periosteum damage was more severe and hematoma formation was smaller in the osteotomy model, resulting in a delay in biological healing and restoration of the biomechanical properties. CONCLUSIONS: Investigators should consider the difference between the closed fracture and open osteotomy models when selecting an animal model to investigate fracture healing.  相似文献   
102.

Objective

The purpose of this study is to evaluate the clinical utility of adding lateral approach to conventional vertical approach for prone stereotactic vacuum-assisted breast biopsies.

Materials and Methods

From April 2010 to May 2012, 130 vacuum-assisted stereotactic biopsies were attempted in 127 patients. While a vertical approach was preferred, a lateral approach was used if the vertical approach failed. The success rate of biopsies utilizing only a vertical approach was compared with that using both vertical and lateral approaches and the breast thickness for both procedures was measured and compared with that for vertical approach. In addition, pathology results were evaluated and the causes of the failed biopsies were analyzed.

Results

Of the 130 cases, 127 biopsies were performed and 3 biopsies failed. The success rate of the vertical approach was 83.8% (109/130); however, when the lateral approach was also used, the success rate increased to 97.7% (127/130) (p = 0.0004). The mean breast thickness was 2.7 ± 1 cm for the lateral approach and 4 ± 1.2 cm for the vertical approach (p < 0.0001). The histopathologic results in 76 (59.8%) of the biopsies were benign, 23 (18.1%) were high-risk lesions, and 28 (22.0%) were malignant. The causes of biopsy failure were thin breasts (n = 2) and undetected difficult lesion location (n = 1).

Conclusion

The addition of lateral approach to conventional vertical approach in prone stereotactic vacuum-assisted breast biopsy improved the success rate of stereotactic biopsy, especially in patients with thin breasts.  相似文献   
103.

Background

Since delta-shaped gastroduodenostomy was introduced, many surgeons have utilized laparoscopic distal gastrectomy (LDG) with totally intracorporeal Billroth I (ICBI) for gastric cancer, because it is expected to have several advantages over laparoscopic-assisted distal gastrectomy with extracorporeal Billroth I (ECBI). In this study, we compared these two reconstruction options to evaluate their outcomes.

Methods

The data of 166 gastric cancer patients who underwent LDG performed by a single surgeon between April 2009 and February 2012 were analyzed retrospectively. The subjects were divided into ECBI (n = 106) and ICBI (n = 60) groups, and then the clinical characteristics, surgical outcomes, symptoms, and change in BMI at 3 months after surgery were compared. Furthermore, a rapid systematic review and meta-analysis were conducted.

Results

The operative time was significantly shorter in the ICBI group (197.4 ± 45.5 vs. 157.1 ± 43.9 min), but blood loss was similar between the groups. Regarding surgical outcomes, there were no significant differences in the length of hospital stay, soft diet initiation, visual analogue scale, frequency of analgesics injection, and postoperative white blood cell counts and C-reactive protein levels between the groups. The surgical complication rates were 5.7 and 13.3 % in the ECBI and ICBI groups, respectively, and one case of anastomosis leakage was observed in each group. At 3 months after surgery, reflux symptoms were more frequent in the ICBI group, but other gastrointestinal symptoms and the change of BMI were similar between the groups. The meta-analysis revealed no significant differences in the operative time, time to first flatus, length of hospital stay, frequency of analgesic usages, and rates of anastomosis complications between the groups.

Conclusions

We could not demonstrate the clinical superiority of ICBI over ECBI based on our data and a rapid systematic review and meta-analysis. The anastomosis method may be selected according to patient conditions and the surgeon’s preference.  相似文献   
104.

Objective

To evaluate the radiographic and MR appearance of idiopathic synovial osteochondromatosis of the hip.

Materials and Methods

Radiographs and MR images of 15 patients with idiopathic synovial osteochondromatosis of the hip were assessed. The former were analysed in terms of the presence of 1) juxta-articular calcified and/ or ossified bodies, 2) osteophytes, 3) bone erosion, 4) juxta-articular osteopenia, and 5) joint space narrowing, while for the latter, analysis focused on 1) the configuration of intra-articular bodies, 2) bone erosion, 3) synovial thickening, 4) conglomeration of intra-articular bodies, and 5) extra-articular extension.

Results

At hip radiography, juxta-articular calcified and/ or ossified bodies were seen in 12 of the 15 patients (80%), bone erosion in eight (53%), osteophytes in seven (47%), juxta-articular osteopenia in five (33%) and joint space narrowing in five (33%). In eight patients (53%), MR imaging depicted intra-articular bodies of focal low signal intensity at all pulse sequences, and areas of iso-intensity at T1WI and hyperintensity at T2WI. In three (20%), intra-articular bodies of focal low signal intensity and areas of hyperintensity at all pulse sequences were observed, with areas of iso-intensity at T1WI and hyperintensity at T2WI, while in four (27%), intra-articular bodies of only focal low signal intensity at all pulse sequences were apparent. Synovial thickening was present in 13 patients (87%), bone erosion in 11 (73%), conglomeration of the intra-articular bodies in 11 (73%), and an extra-articular herniation sac in six (40%).

Conclusion

The most common radiographic finding of synovial osteochondromatosis of the hip was the presence of juxta-articular calcified and/ or ossified bodies. MR imaging depicted intra-articular bodies of focal low signal intensity at all pulse sequences, with areas of iso-intensity at T1WI and hyperintensity at T2WI. In addition, the presence of an extra-articular herniation sac was not uncommon.  相似文献   
105.
CT and MR imaging features of adnexal torsion.   总被引:15,自引:0,他引:15  
In adnexal torsion, the ovary, ipsilateral fallopian tube, or both twist with the vascular pedicle, resulting in vascular compromise. Unrelieved torsion is likely to cause hemorrhagic infarction as the degree of arterial occlusion increases. Therefore, early diagnosis is important to preserve the affected ovary. Adnexal torsion commonly accompanies an ipsilateral ovarian neoplasm or cyst but can also occur in normal ovaries, usually in children. Although ultrasonography is typically the initial emergent examination, computed tomography (CT) and magnetic resonance (MR) imaging may also be useful diagnostic tools. Common CT and MR imaging features of adnexal torsion include fallopian tube thickening, smooth wall thickening of the twisted adnexal cystic mass, ascites, and uterine deviation to the twisted side. Uncommon imaging findings in adnexal torsion that are specific to hemorrhagic infarction include hemorrhage in the thickened fallopian tube, hemorrhage within the twisted ovarian mass, and hemoperitoneum. Additional imaging findings that can suggest hemorrhagic infarction include eccentric smooth wall thickening exceeding 10 mm in a cystic ovarian mass converging on the thickened fallopian tube and lack of contrast enhancement of the internal solid component or thickened wall of the twisted ovarian mass. Early diagnosis can help prevent irreversible structural damage and may allow conservative, ovary-sparing treatment.  相似文献   
106.
BACKGROUND AND AIMS: The Dendroaspis natriuretic peptide (DNP), which was recently isolated from the venom of the green Mamba snake, Dendroaspis angusticeps, is a 38 amino acid peptide containing a 17 amino acid disulfide ring structure. The purpose of this study was to evaluate the effect of haemodialysis (HD) on the plasma concentration of DNP, and to investigate the relationship between the 2-D echocardiographic parameters and the changes in the plasma DNP levels during HD. METHODS: Forty-five haemodialysis patients and 22 healthy individuals underwent a measurement of plasma DNP-like immunoreactivity, serum creatinine, haematocrit, blood pressure and bodyweight before and after each HD session. Echocardiography was performed before and after HD. The peak early diastolic transmitral flow velocity (E), peak late diastolic transmitral flow velocity (A), and E/A ratio were measured by using a pulsed Doppler echocardiogram. RESULTS: The plasma DNP-like immunoreactivity of those in the pre-HD state was significantly higher (235.6 +/- 45.8 pg/mL) than those of the healthy subjects (105.3 +/- 31.1 pg/mL). In addition, the plasma DNP-like immunoreactivity was significantly decreased after HD (204.4 +/- 55.4 pg/mL). The left atrial diameter, left ventricular diameter at end diastole and end systol, E velocity, A velocity, E/A ratio and inferior vena cava diameter were significantly decreased after HD. There were significant correlations between the changes of plasma DNP-like immunoreactivity and the changes in the bodyweight and inferior vena cava diameter, respectively. CONCLUSION: These results suggest that the plasma DNP-like immunoreactivity might be involved in the regulation of the blood volume in patients undergoing HD.  相似文献   
107.
To validate the adverse effects of subluxation of the femoral head in Legg-Calve-Perthes disease, the authors made an experimental model of Perthes disease with subluxation in growing rabbits by interrupting the epiphyseal artery (devascularization) and immobilizing the knee in extension (immobilization). Seventy-two rabbits, 4 to 5 weeks old, were divided into three groups: group A with both devascularization and immobilization (25 rabbits), group B with devascularization only (25 rabbits), and group C with immobilization only (22 rabbits). In each experimental group, four to six rabbits each were killed at 1, 2, 4, 8, and 12 weeks. After reviewing the serial radiographs and gross specimens, the authors found six radiologic and six macroscopic abnormalities. The incidence and the severity of deformity in group A rabbits were higher than that of groups B or C in terms of the overall incidence of deformities (P <0.001), head deformity scores (P <0.001), and the incidence of a total collapse of the capital femoral epiphysis. In conclusion, subluxation of the immature femoral head with avascular necrosis in rabbits increased femoral head deformities.  相似文献   
108.
The purpose of the present study was to compare the clinical and radiographic results between 2 procedures, lateral opening wedge calcaneal osteotomy (LCL) and medial calcaneal sliding-opening wedge cuboid-closing wedge cuneiform osteotomy (3C) in patients with planovalgus foot deformity. A total of 38 patients who underwent either LCL (18 patients, 28 feet) or 3C (20 patients, 32 feet) were included in the present study. The etiology of the planovalgus foot deformity was idiopathic in 16 feet and cerebral palsy in 44 feet. The 2 procedures used in the present study were indicated in symptomatic (pain or callus) children in whom conservative treatment, such as shoe modifications or orthotics, had been applied for more than 1 year but had failed. The patients were evaluated preoperatively, postoperatively, and at the last follow-up visit, both clinically and radiologically, and the interval to union and postoperative courses were compared between the 2 groups. In the LCL group, 19 of the 28 feet (68%) showed a satisfactory outcome and 9 (32%) an unsatisfactory outcome. In the 3C group, 28 of the 32 feet (88%) showed a satisfactory outcome and 4 (12%) an unsatisfactory outcome. The clinical results were not significantly different between the 2 groups, with mild to moderate pes planovalgus deformity. However, the clinical results were better in the 3C group with severe pes planovalgus deformity than in the LCL group with severe pes planovalgus deformity. All 4 radiographic parameters were improved at the last follow-up visit in both groups. In particular, the talar–first metatarsal angle and the calcaneal pitch angle on the weightbearing lateral radiographs were significantly improved in the 3C group with mild to moderate planovalgus foot deformity. All 4 parameters were significantly improved in the 3C group with severe planovalgus foot deformity. No significant differences were observed between the 2 groups in terms of the interval to union and postoperative care. No case of postoperative deep infection or nonunion was encountered in either group. 3C is a more effective procedure than LCL for the correction of pes planovalgus deformity in children, especially severe pes planovalgus deformities.  相似文献   
109.

Background

The purpose of this study is to report a modified transtibial technique to approach the center of anatomical femoral footprint in anterior cruciate ligament (ACL) reconstruction and to investigate the accurate femoral tunnel position with 3-dimensional computed tomography (3D-CT) and radiography after reconstruction.

Methods

From December 2010 to October 2011, we evaluated 98 patients who underwent primary ACL reconstruction using a modified transtibial technique to approach the center of anatomical femoral footprint in single bundle ACL reconstruction with hamstring autograft. Their femoral tunnel positions were investigated with 3D-CT and radiography postoperatively. Femoral tunnel angle was measured on the postoperative anteroposterior (AP) radiograph and the center of the femoral tunnel aperture on the lateral femoral condyle was assessed with 3D-CT according to the quadrant method by two orthopedic surgeons.

Results

According to the quadrant method with 3D-CT, the femoral tunnel was measured at a mean of 32.94% ± 5.16% from the proximal condylar surface (parallel to the Blumensaat line) and 41.89% ± 5.58% from the notch roof (perpendicular to the Blumensaat line) with good interobserver (intraclass correlation coefficients [ICC], 0.766 and 0.793, respectively) and intraobserver reliability (ICC, 0.875 and 0.893, respectively). According to the radiographic measurement on the AP view, the femoral tunnel angles averaged 50.43° ± 7.04° (ICC, 0.783 and 0.911, respectively).

Conclusions

Our modified transtibial technique is anticipated to provide more anatomical placement of the femoral tunnel during ACL reconstruction than the former traditional transtibial techniques.  相似文献   
110.
ObjectiveThe efficacy and safety of manual aspiration thrombectomy using Penumbra in an acute occlusion of large intracranial arteries has been proven in many previous studies. Our study aimed to retrospectively assess the efficacy and safety of manual aspiration thrombectomy using Penumbra in patients with small vessel occlusions (M2 segment of the MCA).MethodsWe conducted a retrospective review of 32 patients who underwent manual aspiration thrombectomy using the Penumbra 4 MAX Reperfusion Catheter for treatment of an M2 occlusion between January 2013 and November 2014. We evaluated immediate angiographic results and clinical outcomes through review of patient electronic medical records.ResultsThere were slightly more men in this study (M : F=18 : 14) and the median age was 72.5 (age range : 41–90). The rate of successful recanalization (TICI grade ≥2b) was 84% (27/32). NIHSS at discharge and favorable clinical outcomes at 3 months were significantly improved than baseline. Median initial NIHSS score was 10 (range : 4–25) and was 4 (range : 0–14) at discharge. Favorable clinical outcomes (mRS score ≤2 at 3 months) were seen in 25 out of 32 patients (78%). There were no procedure-related symptomatic intracerebral hemorrhages. One patient expired after discharge due to a cardiac problem.ConclusionManual aspiration thrombectomy might be safe and is capable of achieving a high rate of successful recanalization and favorable clinical outcomes in patients with distal cerebral vessel occlusion (M2).  相似文献   
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