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81.
Osteoarthritis (OA) is a progressive joint disorder which affects cartilage and subchondral bone. Calcitonin gene‐related peptide (CGRP) plays a role in bone metabolism. The purpose of this study is to examine the therapeutic effect of the blocking CGRP on OA progression in mice by inhibition of subchondral bone sclerosis. OA was induced by the resection of the medial meniscotibial ligament of the knee in C57/BL6 mice. An intraperitoneal injection of the CGRP receptor antagonist (BIBN4096) was administered after OA surgery. At 1, 4, and 8 weeks after injection, histological analysis were performed. In vitro, the effect of CGRP and BIBN4096 on osteogenesis and osteoclastogenesis was analyzed. BIBN4096 could prevent cartilage degeneration and subchondral bone sclerosis. The OARSI score in the BIBN4096 group was significantly lower than that in the control. In vitro, CGRP up regulated osteocalcin expression, but its expression was down regulated by BIBN4096. CGRP inhibited osteoclastogenesis of raw 267.4 cells, but its effect was reduced by the addition of BIBN4096.The current study showed that subchondral bone sclerosis and increasing expression of CGRP occurs in the early phase of OA in relation to cartilage degeneration, and that BIBN4096 could effectively attenuate OA progression. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1177–1184, 2016.  相似文献   
82.

Purpose

Several video-assisted and robotic surgery techniques have been reported for resection of the thyroid and parathyroid glands. Our institute has started performing endoscopic thyroidectomy using the Lap-protector and E·Z-access system, referred to as E·Z-access using video-assisted neck surgery (EZ-VANS). In this report, we evaluate the safety and efficacy of this technique.

Methods

From January 2007 to September 2014, 110 patients underwent resection of a primary thyroid tumor, 73 who underwent a cervical collar incision (the Open group) and 37 underwent EZ-VANS (the EZ-VANS group).

Results

The average operating time was 159 and 172 min in the Open group and EZ-VANS group, respectively; the amount of blood loss was 46.5 and 54.7 ml, respectively; and the length of hospital stay after surgery was 4.3 and 5.2 days, respectively, with no significant differences observed between the two groups. The learning curve for the EZ-VANS technique was shorter than for open surgery.

Conclusions

We confirmed that the EZ-VANS technique is a safe and useful method for resection of benign and early malignant thyroid tumors.
  相似文献   
83.
Purpose  Restorative proctocolectomy has become the most common surgical option for patients with familial adenomatous polyposis (FAP). However, adenomas may develop in the ileal pouch mucosa over time, and even carcinoma in the pouch has been reported. Our aim was to evaluate the prevalence, nature, and etiology of ileal pouch and nonpouch adenomas and carcinoma in patients with FAP. Patients and methods  This was a retrospective study of 31 FAP patients with Kock’s continent ileostomy (Kock; n = 8), ileorectal anastomosis (IRA; n = 7), and ileal pouch–anal anastomosis (IPAA) (n = 16). All patients were followed with a standardized protocol including chromoendoscopy and biopsies of visible polyps in the ileal pouch and nonpouch mucosa. Results  Sixteen of 24 pouch patients (Kock and IPAA) developed adenomas in the ileal pouch mucosa, and all patients with IRA developed adenomas in the rectal mucosa. The prevalence of ileal adenomas was significantly higher in pouch patients than in IRA patients (P = 0.002). Only one patient with Kock showed adenoma in the prepouch area. Two cases of adenocarcinomas and one case of advanced adenoma were found in the ileal pouch mucosa. Conclusion  Our results show a high frequency of adenomas in the ileal pouch mucosa, with evolution into carcinoma in some patients. Regular endoscopic surveillance of the pouch is recommended at a frequency similar to that for the rectal mucosa after IRA in pouch patients with FAP.  相似文献   
84.
Although laminar screw fixation is often used at the C2 and C7 levels, only few previous case reports have presented the use of laminar screws at the C3-C6 levels. Here, we report a novel fixation method involving the use of practical laminar screws in the subaxial spine. We used laminar screws in the subaxial cervical spine in two cases to prevent vertebral artery injury and in one case to minimize exposure of the lamina. This laminar screw technique was successful in all three cases with adequate spinal rigidity, which was achieved without complications. The use of laminar screws in the subaxial cervical spine is a useful option for posterior fusion of the cervical spine.  相似文献   
85.

Purpose

Primary spinal osteosarcoma is quite rare, and the 5-year survival rate is very low. Because of its rarity, successful treatment experience with spinal osteosarcoma is limited. The purpose of this study is to report the effect of therapy of primary osteosarcoma of spine by carbon-ion radiotherapy (CIRT) and long-term follow.

Methods

A 70-year-old with primary spinal osteosarcoma who received CIRT underwent combined anterior artificial vertebral body replacement and posterior lumbar fusion (L1–L5) 3 years later.

Results

According to the surgical resection of tumoral lesion, pathological results showed that the intertrabecular space previously filled with tumor cells on the initial biopsy sample now contained necrotic tissue without tumor cells. This means that primary osteosarcoma of the spine was completely eliminated and achieved local control with CIRT, with a 7-year follow-up after the initial treatment.

Conclusions

Carbon ion beam treatment is an effective local treatment for patients with spinal osteosarcoma for whom surgical resection is not a feasible option, especially for elderly patients. However, more patients need to be evaluated over a longer term to assess the curative effect of CIRT.
  相似文献   
86.
The influence of hip position on knee flexion angle before total knee arthroplasty (TKA) and that after TKA were investigated and compared. Sixty-six patients (70 knees) with osteoarthritis who were undergoing TKA were examined using lateral radiographs of maximum knee flexion angle with the hip joint at 0 degrees extension and 90 degrees flexion. The postoperative rate of decrease in knee flexion angle caused by hip extension was significantly larger compared with the value before surgery. The preoperative rate of decrease in knee flexion angle caused by hip extension showed strong inverse correlation with the preoperative and postoperative knee flexion angle ratio. In conclusion, tightness of the extensor mechanism is present in all knees undergoing TKA and especially has a strong influence on the postoperative flexion angle of the knee.  相似文献   
87.

Purpose

Radial artery cannulation is a common medical procedure for anesthesia and critical care. To establish the ideal wrist position for radial artery cannulation, we performed ultrasound examinations of the radial artery to investigate the effect of the angle of wrist extension on radial artery dimensions.

Clinical features

Measurements were performed in 17 healthy subjects and 17 surgical patients scheduled for coronary artery bypass graft (CABG) surgery. The radial artery was echographically visualized near the styloid process of the radius at the wrist. Radial artery dimensions were measured at wrist joint angles of 0, 15, 30, 45, 60 and 75°.

Observations

In both groups, radial artery height was affected by the wrist joint angle. Vessel height was decreased at 60° (one way ANOVA P = 0.027 vs 0°) and 75° (P < 0.001 vs 0, 15, 45°) in healthy subject and at 75° in CABG patients (P < 0.001 vs 0°). The mean differences in radial artery height at 0 and 75° were 0.33 ± 0.09 mm and 0.20 ± 0.06 mm for healthy and CABG patients, respectively. Vessel width was not affected by wrist joint angulation up to 75° of extension.

Conclusion

Our results demonstrate that in healthy subjects, radial artery dimensions are unaltered when the wrist joint is extended up to an angle of 45°. Extension at 60° for healthy subjects and 75° for CABG patients, however, results in a decrease in the height of the radial artery, which could possibly render arterial catheterization more difficult.  相似文献   
88.

Purpose

The aim of this study was to investigate the attachment of the medial patellofemoral ligament (MPFL) using cadaver specimens and establish an anatomic basis for optimal MPFL reconstruction to achieve better patella stability.

Methods

Sixteen knees of eight cadavers were used in this study. The relationship of the MPFL with quadriceps muscles was investigated from outside after removal of the distal part of the vastus medialis and the rectus femoris and then evaluated from intra-articular side after release of lateral margin of the vastus lateralis muscle, patella and patella tendon.

Results

The proximal fibres of MPFL were mainly attached to the vastus intermedius tendon, without tight adhesion to the vastus medialis. The distal fibres of MPFL were interdigitated with the deep layer of the medial retinaculum that was attached to the medial margin of the patella tendon.

Conclusion

These findings imply that MPFL, which was directly attached to the vastus intermedius and patella and indirectly continued to the patella tendon, could keep pulling them medially as one unit and consequently make the patella move smoothly on the trochlea during whole movement of the knee. Clinically, dysfunction of both proximal and distal MPFL fibres should be considered in the diagnosis and treatment of patella instability after traumatic patella dislocation. MPFL reconstruction with both fibres has a possibility to lead ideal function of MPFL and better instability of the patella.  相似文献   
89.

Objective

To determine the optimal accumulation time for three-dimensional positron emission tomography (3D-PET) with 18F-2-fluoro-2-deoxy-d-glucose (18F-FDG) to detect the brain uptake pattern typical of Alzheimer’s disease (AD).

Methods

Patients with mild AD or amnestic mild cognitive impairment (MCI) and normal control subjects were recruited in the Japanese Alzheimer’s disease neuroimaging initiative and examined with a PET scan during the 30–60 min after FDG injection. Three independent blinded experts interpreted the 30- to 60-min sum images, and images of patients with AD and MCI presenting AD patterns and normal subjects presenting normal patterns were used in the analysis. Early-scan (ES) and late-scan (LS) images were obtained from the data acquired at 30–35 min and 55–60 min after the injection, respectively. Separate target regions of interest (ROI) for ES and LS were defined as areas of significant reductions in the posterior cingulate and parietotemporal lobe in both hemispheres from the results of an initial cohort with 21 patients (AD 16, MCI 5) and 19 controls. A subsequent sample of 36 (AD 9, MCI 27) patients and 38 controls were used to compare the diagnostic capability of ES and LS using Z scores within the target ROI in individual statistical parametric mapping analysis.

Results

Compared to LS, ES showed lower activity in the frontal lobes and higher activity in the venous sinus than LS; however, the diagnostic capability of ES and LS did not significantly differ (sensitivity 0.97 and 0.97, specificity 0.82 and 0.84, area under the receiver-operating characteristic curve 0.96 and 0.97, respectively).

Conclusions

For a qualitative diagnosis of the AD pattern in 3D FDG-PET, results of ES were equivalent to those of LS. ES may be an option to shorten the entire PET procedure time, particularly in diagnosing early stages of AD.  相似文献   
90.
OBJECT: The effects of percutaneous transluminal angioplasty (PTA) and stent placement for stenosis of the petrous or cavernous portion of the internal carotid artery (ICA) were compared. METHODS: Twenty-four patients with symptomatic, greater than 60% stenosis of the petrous or cavernous portion of the ICA were treated using PTA or stent placement; 15 were treated with PTA and nine with stent insertion. Initial and follow-up results (> 3 months posttreatment) were compared in each group. Stenotic portions of the ICA were successfully opened in 13 of 15 patients in the PTA group, and in all nine patients in the stent-treated group. In one case in the PTA group stent delivery was attempted; however, the device could not pass through the vessel's tortuous curve, and PTA alone was performed in this case. Postoperatively, the mean stenotic ratio decreased from 72.1 to 29.6% in the PTA group, and from 75.6 to 2.2% in the stent-treated group. In four patients in the PTA group, stenoses greater than 50% were demonstrated on follow-up angiography performed at 3 to 6 months after PTA. In the stent-treated group, no restenosis was encountered, although in one case acute occlusion of the stent occurred; the device was recanalized with PTA and infusion of tissue plasminogen activator. This case was the only one of the 24 in which any neurological deficits related to the endovascular procedure occurred. Stent placement brought a greater gain in diameter than did PTA at the initial and late follow-up period; this gain was statistically significant. CONCLUSIONS: Stent placement is more effective than PTA for stenosis of the petrous or cavernous portion of the ICA from the viewpoint of initial and late gain in diameter.  相似文献   
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