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91.

Purpose

The goal of this study was to compare the accuracy and cranial facet joint violation rates between percutaneous pedicle screw placements using conventional fluoroscopy and intraoperative 3-D CT (O-arm) computer navigation.

Methods

We reviewed 194 pedicle screw of 28 consecutive patients who underwent minimally invasive lumbar or thoracic spinal stabilization. The accuracy of screw placement was evaluated according to two criteria published by Neo et al. and Upendra et al. Facet joint violation was evaluated according to the classification described by Babu et al.

Results

Upon Neo grading, CFT group had 19.4 % (14/72) pedicle breach rate and CT-IGN group had a 5.7 % (7/122) pedicle breach rate (p < 0.005). The same sets of screws were also assessed using the outcome-based classification established by Upendra. There were no screw caused neurovascular injuries (type 3 = 0) in both groups. The results showed that 87.5 % (63/72) screws had acceptable placements (type I) and 12.5 % (9/72) had unacceptable placements (type II) in CFT group. In contrast, 94.3 % (115/122) screw had acceptable placements (type I) and only 5.7 % (7/122) had unacceptable placements (type II) in CT-IGN group. Additionally, CFT group had a significantly higher facet joint violation rate of 30.5 % (11/36) than CT-IGN group that had a 3.8 % (3/79) violation rate (p < 0.005).

Conclusion

This study indicated the use of intraoperative CT imaging (O-arm) navigation in PPS placement have very beneficial implications for MIS.
  相似文献   
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94.

Background

Nodal metastasis is an important clinical issue in gastric cancer patients. This study was designed to investigate the clinical usefulness of the positive lymph node ratio (PLNR), which reflects both metastatic and retrieved lymph node numbers, in patients with pN3 gastric cancer.

Methods

We retrospectively analyzed the records of 138 consecutive pN3 patients who underwent curative gastrectomy with lymphadenectomy from 2000 to 2012.

Results

A PLNR of 0.4 was proved to be the best cutoff value to stratify the prognosis of patients with pN3 gastric cancer (P?<?0.001). Univariate and multivariate analyses revealed that older age, larger tumor size (≥10 cm), and PLNR?≥?0.4 [P?<?0.001, HR 3.1 (95 % CI 1.7–5.4)] were independent prognostic factors in pN3 gastric cancer. Regarding the recurrence, patients with PLNR <0.4 had a significantly lower rate of lymph node recurrence than those with PLNR ≥0.4 (P?=?0.020). There was no significant difference in the lymph node recurrence rate between N3a and N3b patients in the PLNR <0.4 group [P?=?0.546, 11.6 % (7/60) vs. 12.5 (1/8)], indicating a better local control regardless of pN3 subgroups.

Conclusions

PLNR is useful to stratify the prognosis and evaluate the extent of local tumor clearance in pN3 gastric cancer.
  相似文献   
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Annals of Surgical Oncology - Transient receptor potential vanilloid 2 (TRPV2) is a highly Ca2+-permeable ion channel that is involved in a number of cellular processes. It is expressed in various...  相似文献   
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Osteoarthritis (OA) is a group of common, chronic, and painful inflammatory joint diseases. One important finding in OA patients is a remarkable decrease in the molecular weight of hyaluronic acid (HA) in the synovial fluid of affected joints. Therapeutic HA is available to patients in most parts of the world as a viscosupplementation product for the treatment of OA. Previous clinical reports show that high molecular weight HA (HMWHA) more effectively relieves pain than low molecular weight HA (LMWHA). However, the mechanism behind this finding remains unclear. In this study, we investigated whether a LMWHA (Low‐0.9 MDa) and two types of HMWHA (High‐1.9 MDa and 6 MDa) differentially affected chondroregulatory action. We tested this using ATDC5 cell, a murine chondrocytic cell line widely used in culture systems to study chondrogenic differentiation. We found that HMWHA, especially hylan G‐F 20 (High‐6 MDa), significantly induced aggrecan and proteoglycan accumulation, nodule formation, and mRNA expression of chondrogenic differentiation markers in a time‐ and dose‐dependent manner. In addition, we showed that HMWHA prevented TNF‐α induced inhibition of chondrogenic differentiation, with no effect on cell proliferation or viability. These results reveal that HMWHA significantly promotes chondrogenic differentiation of ATDC5 cells in vitro, and suggest that HMWHA plays a significant chondroregulatory role in vivo. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1619–1627, 2014.  相似文献   
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100.

Purpose

Clumsiness and numbness of the upper extremity is one of the most common complaints of patients with cervical myelopathy. However, most previous evaluations after cervical laminoplasty have only been based on physicians’ points of view. We used Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) self-report questionnaire, which was designed to measure physical function and symptoms in people with upper-limb disorders to evaluate functional outcomes after laminoplasty.

Methods

Ninety-four patients who underwent laminoplasty for cervical myelopathy and replied to the questionnaire were included in this study. The average age was 62 years, and mean follow-up period was 61 months. The Japanese Orthopedic Association (JOA) score, Neck Disability Index (NDI), Short-Form Health Questionnaire of 36 questions (physical component score, PCS), upper-extremity pain (Numerical Rating Scale), and QuickDASH (0–100, 0 being least severe) were used to evaluate surgical outcomes. Satisfaction with treatment was also investigated, and internal consistency and criterion-related validity were evaluated. The QuickDASH cutoff value for patient satisfaction was determined by receiver operating characteristic curve (ROC) analysis.

Results

The mean total JOA scores were 10 before and 13 after surgery, and average postoperative QuickDASH score was 30. Cronbach α of the QuickDASH was 0.94. QuickDASH was significantly correlated with JOA score for upper-extremity motor and sensation, NDI, PCS, and pain. Cutoff value of the QuickDASH was 34.0 by ROC analysis. Significantly better QuickDASH scores were found for patients who were satisfied with treatment than for those who were not, whereas JOA score for upper-extremity motor function did not show a significant difference.

Discussion

QuickDASH had significant correlations with disease-specific JOA scores and other generic outcome measures. Moreover, QuickDASH significantly reflected patients’ satisfaction with treatment, whereas the JOA score for upper-extremity motor function did not.

Conclusion

QuickDASH was useful in evaluating upper-extremity functional outcomes after cervical laminoplasty.  相似文献   
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