改良带旋髂深血管蒂髂骨瓣的应用解剖研究及临床应用

目的：介绍一种改良带旋髂深血管蒂髂骨瓣的制备方法。方法：利用5具经10％甲醛固定的国人成人标本,模拟临床手术,对髂骨区相关解剖进行观察、摄片;临床应用改良旋髂深血管蒂髂骨瓣修复下颌骨体部缺损6例。结果：应用改良方法完成5具10侧标本带旋髂深血管蒂髂骨瓣的制备。临床应用6例手术顺利移植骨瓣,全部成活;无1例发生术后并发症。结论：改良法制备带旋髂深血管蒂髂骨瓣的术式安全、可靠,可避免损伤腹壁组织及股外侧皮神经。     

Mechanical evaluation of a bio-active bone cement for total hip arthroplasty

A new bio-active bone cement, known as CAP, has been developed as an alternative to acrylic bone cement. CAP has improved mechanical properties, with a high modulus that is over five times that of PMMA. The effects of this high modulus are examined by finite element analysis, when the CAP is used in place of PMMA to fix the femoral component in total hip prostheses. The results show a higher tensile stress of 8.76 MPa in the CAP cement, compared with 1.99 MPa in the PMMA cement. However, it is also shown that CAP has a superior fatigue strength of approximately 40 MPa, obtained from a cyclic loading test.     

Periprosthetic modelling of femoral component fit using computed tomography data for total hip arthroplasty: a feasibility study

The aim of the work was to create a new three-dimensional periprosthetic multi-criteria optimisation technique to identify the best six degrees of freedom transform to position a porous-coated anatomic cementless femoral component for three factors, including: first, maximisation of the degree of contact achieved between designated bone ingrowth surfaces and the periprosthetic bone; secondly, minimisation of the bone mass to be removed to accommodate the component and thirdly, the extreme constraint of the component to be positioned so that it does not project beyond the periosteum. Discrete integrals were computed over regions of interest derived from the polyhedral component mesh in transaxial CT scan planes, using a polygon scan-conversion algorithm. A new biomedical imaging volume rendering technique utilising dynamic virtual textures was developed to visualise the design trade-offs.Pareto-optima were identified for four femora that matched an average-sized component. The non-linear, multi-modal fit metric was quadratic near minima, with a narrow trough of equivalent fit values within 3 mm of translation and 3 degrees of rotation with respect to the canal axis, and possessed a dependence most pronounced for distal-directed insertion against varus/valgus rotation. The study gives previously unavailable data on the three-dimensional femoral component fit and is the first report that demonstrates that fitting the implant using several design criteria in a multi-criteria optimisation scheme is feasible.