Coverage error of commercial skin pigments as compared to human facial skin tones

Objectives

It is unknown if present-day pigments used for intrinsic colouration of maxillofacial prostheses are representative of human facial skin tones. This study's purpose was to measure L*a*b* values of pigmented elastomers coloured by eleven skin tone pigments and determine coverage error (CE) when the pigments were compared to human facial lip and nose colour data.

Methods

11 skin tone pigments were combined at 0.1%, 1% and 10% by weight with A-2186 elastomer (n = 3). L*a*b* values were measured with a spectrophotometer and group means were used to calculate ΔE* colour differences with each L*a*b* value obtained for human nose and lip. Pigmented elastomer CEs were calculated for nose and lip. Results were compared to CEs for proposed shade guide colours obtained from clustering analyses of facial skin colours.

Results

L* values of pigmented elastomers generally were higher than those measured for nose and lip, whereas a* values were lower. CEs for pigmented elastomers were higher than those obtained from the proposed shade guide obtained from clustered skin measurements.

Conclusions

Overall, the current commercial elastomers appeared to be too white and not red enough to adequately match the skin tones of the subject population. Adjustments must be made to the existing pigmenting system in order to adequately match the skin colours of the study population.

Clinical significance

The creation of a shade guide and a collection of intrinsic pigments representing the realm of human facial skin colours would greatly decrease the time a patient must sit while the clinician is obtaining an acceptable colour match for the silicone to be used for processing the final prosthesis, thereby increasing both patient satisfaction and clinician productivity.     

骨盆Ⅰ-Ⅱ-Ⅳ区肉瘤整块切除后腰盆钉棒重建系统

目的探讨骨盆Ⅰ-Ⅱ-Ⅳ区肉瘤整块切除后新设计的腰盆钉棒重建系统的临床应用。方法回顾性研究中山大学附属第一医院骨肿瘤科,2009年6月到2010年12月期间,行骨盆Ⅰ区、Ⅱ区和Ⅳ区肉瘤整块切除和腰盆钉棒系统重建术的病例资料,评价该术式的治疗效果及术后并发症。入选条件:穿刺活检证实骨盆原发性肉瘤;肺部CT未见转移灶,Eneking分期为ⅡB期;患者能完成规范的新辅助化疗;术前MRI评估证实肉瘤未侵犯髂外动静脉、坐骨神经和盆腔脏器,确认肉瘤累及骨盆Ⅰ-Ⅱ-Ⅳ三个区域。结果 4例累及骨盆Ⅰ区、Ⅱ区和Ⅳ区的原发性肉瘤患者接受肿瘤整块切除后腰盆钉棒系统重建。患者男3例,女1例;平均年龄29.75岁(18～45岁)。病理类型包括:尤文肉瘤2例,软骨肉瘤1例和骨肉瘤1例,尤文肉瘤和骨肉瘤完成新辅助化疗。肉瘤整块切除范围包括骨盆Ⅰ区、Ⅱ区和Ⅳ区肿瘤、肿瘤累及的髂肌、臀中小肌和部分臀大肌,同时采用骨盆髋臼和腰椎椎弓根钉棒系统重建髋臼、骨盆环和腰骶连接。术后3周患者开始进行康复治疗,术后3个月可扶拐行走。术后平均随访14个月(9～19个月),目前尚未发现复发和转移。MSTS功能评分平均为66.67%(63%～73%);Harris髋关节评分良2例,差2例。结论骨盆原发性肉瘤治疗的主要目标是通过广泛切除而获得治愈,通过骨盆环重建挽救下肢的主要功能。骨盆Ⅰ区、Ⅱ区和Ⅳ区肉瘤整块切除和腰盆钉棒系统既能完整的切除肿瘤,又能有效重建骨盆和腰骶连接功能。这种重建方式近期疗效观察能够达到患者及骨肿瘤专科医生的功能期望。     

Impact on the biomechanics of overground gait of using an ‘Echelon’ hydraulic ankle–foot device in unilateral trans-tibial and trans-femoral amputees

Background

If a prosthetic foot creates resistance to forwards shank rotation as it deforms during loading, it will exert a braking effect on centre of mass progression. The present study determines whether the centre of mass braking effect exerted by an amputee's habitual rigid ‘ankle’ foot was reduced when they switched to using an ‘Echelon’ hydraulic ankle–foot device.

Methods

Nineteen lower limb amputees (eight trans-femoral, eleven trans-tibial) walked overground using their habitual dynamic-response foot with rigid ‘ankle’ or ‘Echelon’ hydraulic ankle–foot device. Analysis determined changes in how the centre of mass was transferred onto and above the prosthetic-foot, freely chosen walking speed, and spatio-temporal parameters of gait.

Findings

When using the hydraulic device both groups had a smoother/more rapid progression of the centre of pressure beneath the prosthetic hindfoot (p ≤ 0.001), and a smaller reduction in centre of mass velocity during prosthetic-stance (p < 0.001). As a result freely chosen walking speed was higher in both groups when using the device (p ≤ 0.005). In both groups stance and swing times and cadence were unaffected by foot condition whereas step length tended (p < 0.07) to increase bilaterally when using the hydraulic device. Effect size differences between foot types were comparable across groups.

Interpretation

Use of a hydraulic ankle–foot device reduced the foot's braking effect for both amputee groups. Findings suggest that attenuation of the braking effect from the foot in early stance may be more important to prosthetic-foot function than its ability to return energy in late stance.     

Both immediate and delayed intracavernous injection of autologous adipose-derived stromal vascular fraction enhances recovery of erectile function in a rat model of cavernous nerve injury

Background

Intracavernous injection of cultured adipose-derived stem cells (ADSCs) effectively restores erectile function in cavernous nerve (CN)–injured rats when administered at the time of injury. However, culturing exposes ADSCs to the risk of contamination and dedifferentiation.

Objective

Explore the effect of uncultured autologous adipose-derived stromal vascular fraction (SVF) on improving erectile function in a rat model of CN injury when administered at the time of injury or 4 wk after injury.

Design, setting, and participants

Eighty-nine male Sprague Dawley rats were randomly divided into four groups. CN injury or sham surgery was performed at the start of the study, and rats were treated with either SVF or vehicle. Functional testing and histologic analysis were performed 12 wk after CN crush or sham surgery.

Intervention

We used intracavernous injection of saline immediately after CN crush (n = 23), intracavernous injection of SVF immediately after CN crush (n = 17), intracavernous injection of SVF 4 wk after CN crush (n = 23), or sham surgery (n = 26).

Outcome measurements and statistical analysis

We studied intracavernous pressure (ICP) response to CN electrostimulation and performed histologic examination of midpenile cross-sections. Data were analyzed using one-way analysis of variance followed by the Tukey-Kramer test.

Results and limitations

Both immediate and delayed treatment with SVF resulted in a significantly increased ICP-to-mean arterial pressure ratio compared with the vehicle-treated group. Both immediate and delayed treatment with SVF significantly increased expression of neuronal nitric oxide synthase and neurofilament in dorsal penile nerves compared to the vehicle group. Furthermore, the smooth muscle-to-collagen ratio within the corpus cavernosum was significantly improved in both of the SVF groups compared to vehicle-treated rats. The main limitation of the study is the lack of determination of the SVF components.

Conclusions

Uncultured autologous SVF injected immediately or 4 wk after CN crush improved erectile function, promoted nerve regeneration, and prevented fibrosis of the corpus cavernosum following CN injury.     

Does mismatch of the femoral component aspect ratio influence the range of knee flexion after posterior-stabi- lized total knee arthroplasty？

Objective: To study whether the range of knee flexion (ROF) is affected by geometrical mismatch of the femoral component and the resultant change in the posterior condylar offset (PCO) after high-flexi...     

人工髋关节翻修术的临床原因分析及假体的选择研究

目的探讨人工髋关节置换术后翻修的临床原因及假体的选择。方法共纳入50例人工髋关节置换术患者,按照距首次行置换术大于或小于5年分为早期组(30例)及晚期组(20例),并按照年龄是否大于50岁分为2组(各25例)。均详细记录患者的病史及行翻修术的原因。结果感染性松动、无菌性松动、假体的磨损、假体周围骨折、关节不稳定均是患者行翻修术的原因,但早期与晚期患者行翻修术的主要原因不同;早期行翻修术的主要原因是感染性松动、假体周围骨折、关节不稳定,而晚期行翻修术的主要原因为无菌性松动、假体的磨损。对于老年患者选择骨水泥型假体较好,而对于更年轻点的患者选择生物型假体较好。结论早期行翻修术与晚期行翻修术的主要原因不同,因根据具体情况治疗。对于老年患者选择骨水泥型假体较好,而对于更年轻点的患者选择生物型假体较好,临床可以根据研究对不同患者选用合适的假体。     

磷酰胆碱接枝涤纶人工血管的生物相容性

目的通过臭氧活化的方法在涤纶人工血管表面接枝2-甲基丙稀酰氧基乙基磷酰胆碱,进行接枝后人工血管血液相容性研究。方法通过臭氧活化的方法,在涤纶人工血管表面接枝2-甲基丙稀酰氧基乙基磷酰胆碱,接枝后的涤纶人工血管修剪后作兔腹主动脉补片(实验组),并和未接枝涤纶人工血管作对照。术后观察兔腹主动脉人工血管通畅率、吻合口狭窄程度、血流量和吻合口周围BrdU阳性细胞数。结果接枝2-甲基丙稀酰氧基乙基磷酰胆碱的涤纶人工血管补片吻合后,兔腹主动脉通畅率较对照组无明显差异;实验组兔腹主动脉吻合口狭窄程度小于对照组,而吻合口血流量大于对照组,吻合口周围BrdU阳性细胞数明显少于对照组,差异有统计学意义(P<0.05)。结论涤纶人工血管经接枝2-甲基丙稀酰氧基乙基磷酰胆碱后,能有效抑制吻合口内膜和平滑肌增生,减少吻合口狭窄程度,增加血流量。     

非骨水泥假体翻修失败的骨水泥型人工髋关节:中期效果评价

背景：非骨水泥假体在初次人工髋关节置换中已取得了很好的疗效,但在翻修术特别是在失败的骨水泥型假体翻修过程中的应用效果仍有待观察。
　　目的：观察以非骨水泥假体翻修失败的骨水泥型人工髋关节的中期效果。
　　方法：对1997年11月至2013年2月以非骨水泥假体对失败的骨水泥型人工髋关节翻修的41例(47髋)患者进行随访,其中翻修骨水泥柄24髋、骨水泥臼23髋。随访X射线片上的假体变化情况,对髋关节行Harris功能评定并分析假体生存率。
　　结果与结论：共33例38髋获得随访,随访时间1.3-14.8年,患者的平均Harris评分由术前的34分(11-66分)增加到末次随访时的85分(55-94分),差异有显著性意义(P <0.01)。36髋(95%)假体获得良好稳定性;2髋发生骨溶解并假体移位(股骨1髋,髋臼1髋)需要再翻修;9髋发生异位骨化(24%)。聚乙烯衬垫年平均磨损量为0.08 mm(0-0.25 mm),磨损率仅与外展角变化存在相关性(P <0.01)。以影像学证明假体松动作为失败标准,利用Kaplan-Meier生存分析法计算非骨水泥假体7年总体存活率为89%,其中髋臼假体和股骨假体的存活率分别为93%及92%。提示用非骨水泥假体对失败的骨水泥型人工髋关节进行翻修能有效地修复骨缺损并达到令人满意的中期临床效果。