一种基于表面肌电信号映射人体下肢运动意图的方法

智能膝关节假肢是截肢患者恢复日常运动的重要辅具。对人体下肢运动意图的识别是实现下肢假肢控制的关键。该文针对此问题,提出了一种通过表面肌电信号预测膝关节角度的方法。对表面肌电提取时域特征,通过 BP 神经网络模型建立平地行走过程中表面肌电信号和膝关节角度的映射关系,预测膝关节角度。     

Results of the Kudo elbow prosthesis in patients with rheumatoid arthritis: a preliminary report

Sixteen elbows in 15 rheumatoid arthritis patients had a total elbow replacement with insertion of a non-constrained surface-replacement prosthesis. One patient died of an unrelated cause, but all the others were available for follow-up (mean follow-up period: 35.4 months). The results were graded according to a modified version of the Morrey elbow score. A good result was seen in 13 elbows and a fair result in two. One infection occurred, which was cured with intravenous antibiotics and maintenance of the prosthesis in place; however, recurrent dislocation persisted. Another patient had postoperative instability with recurrent subluxations. Eleven patients were very satisfied and one was satisfied. The total active range of motion increased significantly from 70.3^o (SD 29.6) to 97.0^o (SD 15.4), mainly by increased flexion. The modified Morrey score increased significantly from 32.7 (SD 13.1) to 89.3 (SD 10.3). Pain decreased from severe (n=12) and moderate (n=3) preoperatively to mild (n=5) and absent (n=10) postoperatively.     

Effect of the amount of thickness reduction on color and translucency of dental monolithic zirconia ceramics

PURPOSE

This study investigated the effect of amount of thickness reduction on color and translucency of dental monolithic zirconia ceramics.

MATERIALS AND METHODS

One-hundred sixty-five monolithic zirconia specimens (16.3 mm × 16.3 mm × 2.0 mm) were divided into 5 groups (Group I to V) according to the number of A2-coloring liquid applications. Each group was then divided into 11 subgroups by reducing the thickness up to 1.0 mm in 0.1-mm increments (Subgroup 0 to 10, n=3). Colors and spectral distributions were measured according to CIELAB on a reflection spectrophotometer. All measurements were performed on five different areas of each specimen. Color difference (ΔE^*_ab) and translucency parameter (TP) were calculated. Data were analyzed using one-way ANOVA and multiple comparison Scheffé test (α=.05).

RESULTS

There were significant differences in CIE L^* between Subgroup 0 and other subgroups in all groups. CIE a^* increased (0.52<R²<0.73), while CIE b^* decreased (0.00<R²<0.74) in all groups with increasing thickness reduction. Perceptible color differences (ΔE^* _ab>3.7) were obtained between Subgroup 0 and other subgroups. TP values generally increased as the thickness reduction increased in all groups (R²>0.89, P<.001).

CONCLUSION

Increasing thickness reduction reduces lightness and increases a reddish, bluish appearance, and translucency of monolithic zirconia ceramics.     

Doppler Echocardiographic Assessment of Pulmonary Prostheses: A Comprehensive Assessment Including Velocity Time Integral Ratio and Prosthesis Effective Orifice Area

Objective. Few reports have been published on the Doppler‐derived echocardiographic data for pulmonary valve prostheses (PVPs). The aim of this study was to provide a comprehensive Doppler echocardiographic assessment of PVPs. Methods. We studied 40 patients (mean age 24.2) with PVPs: 13 (32.5%) mechanical and 27 (67.5%) bioprosthetic valves. After clinical evaluation, all patients underwent complete, two‐dimensional and Doppler studies. Results. In 30 patients with normally functioning PVPs, the mean (SD) peak velocity was 2.33 (0.36) m/s with an average peak pressure gradient of 22.69 (6.7) mm Hg and an average mean pressure gradient of 12.5 (4.1) mm Hg. The mean PVPs velocity time integral (VTI) was 47.49 (12.78) cm with mean right ventricle outflow tract/peak velocity (PV) VTI ratio 0.43 (0.14), mean PVPs effective orifice area was 1.63 (0.36) cm². Metallic PVPs had significantly better hemodynamic Doppler study compared with biologic PVPs. In 9 patients with PVP malfunction, average peak PVPs velocity, average peak pressure gradient, mean pressure gradient, PV VTI, PV/left ventricle outflow tract VTI ratio was significantly increased (P < 0.05). Conclusion. This study contributes to establishing the normal range for Doppler hemodynamics in various PVPs.     

人工假体置换治疗股骨上段骨肿瘤

采用全股骨及半股骨人工假体置换治疗股骨上皮骨肿瘤21例，男13例，女8例．其中骨肉瘤4例（3例为皮质分骨肉瘤），软骨肉瘤9例。骨巨细胞瘤7例，恶性纤维组织细胞瘤1例。经1～17年的随访观察，收到了满意治疗效果。作者认为：术中遵守无瘤手术操作、彻底切除是降低复发率、转移率的关键；人工假体置技术对于肢体的骨肿瘤、骨巨细胞瘤的治疗效果优于软骨肉瘤，软骨肉瘤的治疗效果优于骨肉瘤.     

Bone and Skin-Supported Stereolithographic Surgical Guides for Cranio-Facial Implant Placement

Purpose

Osseointegrated skin-penetrating implants enhance the retention and stability of the craniofacial prostheses and provide the long-term comfort. However, to determine the implant locations is a great challenge facing the surgeon. Implants may either be located in conventional manner or by STL generated surgical guides.

Materials and Methods

Present study reports the CT based 3D virtual modeling, preoperative virtual planning and the implant placement by using a STL surgical guide, in an anotia case.

Results

Employed materials and the methods facilitated the implant surgery while improving the operational security.

Conclusions

CT based 3D virtual modeling of the surgical site, determining the implant locations virtually and the STL guided placement of the craniofacial implants, were found useful applications in order to facilitating the surgical intervention and providing prevention from complications.

     

腔镜辅助保留乳头乳晕乳腺癌手术Ⅰ期假体乳房重建的探讨

目的：探讨腔镜辅助下保留乳头乳晕乳腺癌改良根治术Ⅰ期乳房重建的方法和疗效。方法：对28例Ⅰ、Ⅱ期乳腺癌患者行腔镜下腋窝淋巴结清扫保留乳头乳晕乳腺癌改良根治术,辅助腔镜下一期假体或扩张器植入乳房重建,Ⅱ期扩张器取出假体植入乳房重建。结果：28例中,7例一期植入硅凝胶假体,体积220~325ml。1例乳房体积小于对侧,化疗结束后3个月,更换较大假体。乳腺癌发病率逐年增高,且年轻化,严重威胁着女性生命,切除乳腺也给患者的形体和心理留下巨大创伤。腔镜技术在乳腺外科的应用使部分乳腺癌在治愈疾病的同时获得最佳的美容效果[1]。本科室自2008年6月至2012年6月行行腔镜辅助下保留乳头乳腺癌改良根治术一期乳房重建28例,取得了良好的效果,现报告如下。21例放置扩张器并注水380-500ml,其中3月后2例破裂,再次更换;1例放疗后皮肤破溃,假体外露,取出扩张器,未再更换。20例中放入扩张器6-15月后,化疗结束3月,放疗结束6月,全部更换为解剖型乳房假体;其中13例行健侧乳房上提缩小术,使两侧乳房对称。术后随访12-52个月,中位平均随访时间为32个月,全组无局部复发和远处转移。无包膜挛缩,乳房形态良好,美容效果满意。结论：腔镜辅助下保留乳头乳腺癌改良根治术假体或扩张器一期植入乳房重建,Ⅱ期扩张器取出更换解剖型假体,健侧乳房上提,可作为早期乳腺癌美容效果较好的一种手术治疗方法。     

Genesis Ⅱ与PFC两种假体全膝关节置换术后膝前痛的比较研究

目的 探讨全膝关节置换术后膝前痛与髌骨置换及假体设计的关系,GenesisⅡ与PFC两种股骨假体与髌骨之间的友好性.方法 回顾性分析由同一组高年资医生施行初次全膝关节置换术的145例(145膝)骨关节炎患者的临床资料.均采用后十字韧带替代型全膝关节假体,髌骨置换74例,其中32例使用GenesisⅡ假体、42例使用PFC假体;髌骨未置换71例,其中38例使用GenesisⅡ假体、33例使用PFC假体.术后评估美国特种外科医院(Hospital for Special Surgery,HSS)膝关节评分、髌骨评分、髌骨功能评分、膝关节活动度、膝前痛评分、满意度和X线片上髌骨倾斜和半脱位情况.结果 随访144例,随访时间21～43个月,平均33个月.术后膝前痛发生率:髌骨置换组与未置换组的差异无统计学意义,组内使用GenesisⅡ假体与PFC假体的差异有统计学意义.使用PFC假体者4例再次手术.功能评分:髌骨置换组及髌骨未置换组中使用GenesisⅡ假体与PFC假体术后HSS评分、活动度、满意度的差异均无统计学意义,而术后髌骨评分及髌骨功能评分的差异有统计学意义.结论 术后膝前痛的发生率与是否置换髌骨无关,而与假体设计有关;GenesisⅡ假体与髌骨的关系更加友好.     

髋膝关节置换术患者康复自我效能感在正念与恐动症间的中介效应研究

目的 探讨髋膝关节置换术患者康复自我效能感在正念与恐动症间的中介效应。方法 采用便利抽样法,于2019年7月—2021年2月,选取在杭州市3所三级甲等医院骨科首次行髋或膝关节置换术的348例患者作为调查对象,应用一般资料调查表、恐动症Tampa量表、正念注意觉知量表和康复自我效能感量表进行调查,运用结构方程模型深入剖析康复自我效能感在正念与恐动症间的中介效应。 结果 正念和康复自我效能感均可直接负向预测恐动症（P<0.001,P=0.003）,康复自我效能感在正念与恐动症间起部分中介作用,间接负向预测恐动症,中介效应为-0.232,占总效应的42.49%。 结论 髋膝关节置换术患者的康复自我效能感是正念与恐动症间的中介变量,医护人员可以通过提高患者的正念水平,增强其康复自我效能感,进而弱化患者的恐动心理和行为。