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71.
ObjectiveFull-endoscopic lumbar discectomy (FELD) is a minimally invasive surgical option for recurrent lumbar disc herniation (LDH). Nonetheless, patients’ clinical outcomes may be poorer after surgery for recurrent LDH than for primary LDH. Therefore, we compared patients’ longitudinal clinical outcomes after FELD for recurrent LDH or primary LDH.MethodsThe medical records of patients who underwent FELD for primary LDH (group A) or recurrent LDH (group B) were retrospectively reviewed. The inclusion criteria were: 1) single-level LDH or recurrent LDH at L4-5 or L5-S1, 2) age ≤60 years, 3) previous open discectomy (group B), and 4) ≥6 months of follow-up. In total, 244 patients (group A, 211; group B, 33) were included. Clinical outcomes (Oswestry Disability Index [ODI]; visual analogue pain score for the back and leg [VAS-B] and [VAS-L]) over 24 months of follow-up were compared between groups with a linear mixed-effects model.ResultsAll clinical outcomes significantly improved from pre-operation to 3 months postoperatively (p < 0.01), and the improvement was maintained for 24 months postoperatively in both groups. The clinical outcomes of groups A and B were not significantly different during 24 months follow-up (ODI, p = 0.94; VAS-B, p = 0.11; and VAS-L, p = 0.48). The reoperation rate was 3.3% in group A and 3.0% in group B, but the overall complication rate was higher in group B (9.8%) than in group A (6.6%).ConclusionThe longitudinal clinical outcomes after FELD for recurrent LDH may not be poor as feared. However, the higher complication rate in patients undergoing FELD for recurrent LDH should be noted.  相似文献   
72.
PurposeThe purpose of this study is to investigate the effect of the cross-link position on the rod fracture phenomenon during pedicle subtraction osteotomy (PSO) surgery using finite element model (FEM).MethodsA three-dimensional finite element model of a lumbar spine with sagittal imbalance was constructed using computed tomography data of a 65-year-old female patient. After simulating the standard PSO at the L4 level, we constructed four models, specifically a model without a cross-link and three models with a cross-link at three different sites. The peak von Mises stress (PVMS) of the rod around the PSO site was measured after applying physiological loads (flexion, extension, axial rotation, and lateral bending) in each model.ResultsThe measured PVMS outcomes at the PSO site were 135.8, 135.9, 208.9, and 384.7 MPa for model 1, 2, 3, and 4 during flexion, and 180.0, 180.1, 210.1, and 445.7 MPa during extension. These results show that when the cross-link is located at the PSO site, the rod stress at the PSO site increases significantly during flexion and extension. As the cross-link moved away from the PSO site, the effect on the rod stress decreased. When the cross-link was placed two levels away from the PSO site, the rod stress was scarcely affected.ConclusionWhen the cross-link during PSO surgery was positioned two levels away from the PSO site, the risk of rod fracture did not increase.  相似文献   
73.
Enterogenous cysts are rare benign congenital tumours of the central nervous system. The aim of management is complete resection to minimise the chance of recurrence. To date, management of recurrence has favoured further surgical resection. We describe the case of a recurrent enterogenous cyst of the cervical spine, initially treated with decompression via laminectomy and fenestration. Magnetic Resonance Imaging (MRI) follow up has demonstrated spontaneous recurrence and deflation of the cyst on multiple occasions. We propose that conservative management of recurrent enterogenous cysts may be a valid management option following fenestration or partial resection of the cyst, and that recurrence may not always warrant further surgical intervention.  相似文献   
74.
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76.

Background

Current literature on carbon fiber implant use in foot and ankle surgery is scant. The purpose of this paper is to report medium-term outcomes of hindfoot fusion using a carbon fiber intramedullary nail.

Methods

We retrospectively reviewed 30 cases of hindfoot fusion using carbon fiber intramedullary nail fixation between 2014 and 2017. We excluded revisions and cases with bulk allograft or ankle infection prior to surgery. We reviewed charts for length of followup, radiographic union, and complications.

Results

Eleven patients were included (6 females, 5 males; mean age = 52 ± 15 years; mean BMI = 29.0 ± 6.4 kg/m2). Mean followup was 20 (range, 1.5–107) months. Nine of eleven cases achieved radiographic union while one case developed a complication requiring surgery. The mean time to union was 3 (range, 1.5–6) months.

Conclusions

Carbon fiber implants offer several theoretical advantages over traditional metallic implants. They can be used safely in foot and ankle surgery without concern for high failure or complication rate. Larger scale studies with longer followup are needed on this topic.  相似文献   
77.
目的采用图像融合技术获得T2WI与T2WI-FS的融合图像,评估其在肛瘘及肛周结构显示中的优势。 方法2016年6月至2018年6月,前瞻性选择中山大学附属第一医院29例肛瘘患者进行肛管磁共振(MR)检查,采用图像融合技术获取T2WI与T2WI-FS的融合图像T2WI-Fusion,利用Fisher score算法计算瘘管及肛门括约肌的组织间分辨力Fisher值、脂肪与肛门括约肌间的Fisher值,评估融合图像中瘘管及肛周结构的显示情况。采用改进的双刺激连续质量量表(DSCQS)对T2WI-FS、T2WI、增强3D-VIBE和T2WI-Fusion序列图像进行主观图像质量评价。 结果29例患者均成功获得T2WI与T2WI-FS的融合图像T2WI-Fusion。T2WI-Fusion、T2WI瘘管与括约肌间Fisher均值分别为6.46、3.31,T2WI-Fusion图像对瘘管的显示优于T2WI序列图像(P<0.001)。T2WI-Fusion、T2WI-FS脂肪与括约肌间Fisher均值分别为10.61、2.45,T2WI-Fusion图像对括约肌的显示优于T2WI-FS序列图像(P<0.001)。T2WI-Fusion对瘘管与括约肌的图像质量评价总评分均高于T2WI-FS、T2WI、增强3D-VIBE序列(P<0.001)。 结论MRI图像融合技术同时具备T2WI及T2WI-FS的优势,无需增加扫描序列及扫描时间,且操作简单,花费时间短,显著提高病变及肛周解剖结构的对比度和图像质量。  相似文献   
78.

Purpose

To evaluate nail appearance after nail fusion plasty to treat thumb duplication.

Methods

A modified form of nail fusion plasty was performed on 17 reconstructed thumbs of 16 children with thumb duplications, commencing in January 2010. We assessed nail width and nail, lunular, and nail fold deformities using the Wang-Gao scoring system. All 17 thumbs were evaluated over an average of 32 months (range, 12–48 months) of follow-up.

Results

One patient with bilateral thumb deformities was excluded. The width ratios of 15 reconstructed nails (compared with those of the contralateral thumbs) were 82–118% (average, 97%). Nine thumbs exhibited nail ridges or gaps; the average ridge/gap score was 1.23 (maximum, 2). Six thumbs exhibited lunular deformities; the average score was 1.58 (maximum, 2). Another six thumbs evidenced nail fold deformities; the average score was 1.64 (maximum, 2). Only one thumb exhibited nail dehiscence. Two thumbs had no nail deformity. The final assessments were excellent in 14 cases, good in 2 cases, and fair in 1 case.

Conclusions

We could not significantly reduce the deformity rate of the nail plate, nail fold, or lunula using our new technique, but the deformities were much less marked than previously. Nail fusion plasty usefully enlarges the nail and pulp in patients with hypoplastically duplicated thumbs.  相似文献   
79.
Introduction: TRK fusions occur across a wide range of cancers in children and adults. These fusions drive constitutive expression and ligand-independent activation of the TRK kinase and are oncogenic. Larotrectinib is the first highly potent and selective small molecule ATP competitive inhibitor of all three TRK kinases to enter clinical development.

Areas covered: This review covers the current preclinical and clinical evidence for TRK inhibitors for TRK fusion cancers, focusing on larotrectinib.

Expert commentary: Larotrectinib has demonstrated a remarkable 75% centrally confirmed objective response rate in patients with TRK fusion cancers in phase 1 and phase 2 clinical trials with generally mild side effects. Responses appear independent of the patient’s age, underlying histology, and specific fusion partner and are durable in many patients. Larotrectinib is likely to be the first FDA-approved histology-agnostic molecularly targeted therapy. The evolving role of molecular profiling of advanced cancers is discussed.  相似文献   

80.
目的:总结手术治疗类风湿性关节炎(rheumatoid arthritis,RA)继发寰枢椎脱位的临床疗效。方法:2010年1月~2018年12月收治57例RA继发寰枢椎脱位的患者,男14例,女43例;年龄46~79岁(61.8±12.4岁)。类风湿性关节炎病史2.5~36.8年(17.5±3.7年),诊断RA后出现上颈椎相关症状时间为1.5~19.4年(8.9±2.4年)。患者均有不同程度的枕颈部疼痛、颈部姿势异常和活动受限。术前神经功能ASIA分级:B级3例,C级12例,D级20例,E级22例;JOA评分4~14分(8.7±1.8分),VAS 4~10分(7.4±1.5分)。寰椎前向脱位44例,其中寰齿前间距(anterior atlantodental interval,AADI)>10mm者8例;寰椎后向脱位9例;寰椎前后向脱位4例。6例合并下颈椎不稳,10例合并枕颈部其他畸形。13例枕寰关节先天性融合及骨性融合无枕寰关节活动度者采用枕颈固定融合术治疗(A组);44例有枕寰关节活动度的患者采用寰枢椎融合固定融合术治疗,其中16例寰枢椎脱位牵引不能复位的患者先行前路经下颌下寰枢椎关节松解术再一期后路行寰枢椎融合术治疗(B组),28例寰枢椎脱位牵引能复位的患者直接采用后路寰枢椎融合内固定术治疗(C组)。定期随访患者的临床症状和神经功能改善情况,影像学观察寰枢椎复位和植骨融合情况。结果:患者均顺利完成手术,A组手术时间100~130min(118.2±13.5min),术中出血量100~300ml(190.5±42.8ml);B组手术时间180~240min(221.4±20.3min),术中出血量100~260ml(157.3±36.1ml);C组手术时间100~130min(109.4±12.1min),术中出血量100~200ml(124.1±32.7ml)。术中均未发生椎动脉和脊髓损伤。所有患者随访期间复查颈椎CT及MRI显示寰枢椎序列重建满意,齿状突区域脑脊液线清晰,脊髓无压迫,术后AADI为2~3mm(2.4±0.4mm)。患者均获随访,随访时间12~84个月(34.4±10.3个月),术后12个月随访时,2例ASIA分级B级患者恢复至C级,C级患者6例恢复至D级、3例恢复至E级,9例D级患者恢复至E级,其余患者无变化;JOA评分改善至10~17分(14.6±3.5分),VAS评分降至1~5分(3.6±1.4分),与术前比较均有显著性差异(P<0.05)。1例患者植骨块发生自发性部分吸收,随访1年半时植骨块吸收停止并部分融合,未再次行植骨术;其余患者植骨均融合。随访期间均未发现螺钉松动、移位、断裂和寰枢椎再脱位、失稳现象。结论:RA累及上颈椎时会造成寰枢椎脱位导致脊髓受压,依据枕寰关节活动度情况采用寰枢椎融合术或枕颈融合术治疗可获得良好的临床效果。  相似文献   
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