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The purpose of this paper is to compare fracture‐fixation and bone‐healing promotion efficacies of an intramedullary (IM) nail‐type and an external osteosynthesis plate‐type femoral trochanteric‐fracture implants using the results of a combined multi‐body dynamics and finite element analyses. For both implants, fracture fixation was obtained using a dynamic hip blade which is anchored to the femur head on one end and is connected to the IM rod/plate on the other. The analysis was carried out for two pre‐fracture conditions of the femur: healthy and osteoporotic.

The musculoskeletal dynamics portion of the analysis was used to obtain realistic physiological loading conditions (i.e. muscle forces and joint reaction forces and moments) associated with four typical everyday activities of a patient, namely, walking, lunging, cycling and egress (i.e. exiting a passenger vehicle). The subsequent structural finite element analysis of the fractured femur/implant assembly was employed to quantify fracture‐fixation efficacy (as measured by the extents of lateral (found to be minor), flexural and torsional displacements of the two femur fragments) and the bone‐healing promotion efficacy (as quantified by the fraction of the fractured surface area which experienced desirable contact pressures).

The results obtained show that, in general, the IM‐rod type of implant out‐performs the osteosynthesis plate type of implant over a large range of scenarios involving relative importance of the bone‐healing promotion and fracture‐fixation efficacies, health condition of the femur and the activity level of the patient. More specifically, the more active the patient and the larger extent of osteoporosis in the femur, the more justifiable is the use of the IM‐rod type of implant.

The present approach enables assessment of the fracture‐fixation performance of orthopedic implants under physiologically realistic loading conditions.

The purpose of this paper is to report a rare case of segmental neck of femur fracture (SNoFF) and highlight its quality assurance and governance implications with respect to national guidelines, care pathways and best practice tariff.

Case report of an SNoFF in a 67-year-old woman treated at a district general hospital (DGH) was used in this study.

SNoFF required additional implants that delayed the surgery by five days. The authors were unable to adhere to the British Orthopaedic Association standards for trauma and Scottish Inter-Collegiate Guidelines Network recommendations which indicate that all neck of femur fractures (NoFFs) be fixed within 48 h. Though the patient was discharged without any untoward event and had an uneventful recovery, this case led us to introspect and learn how best to avoid such an incident from repeating again.

This case led to an overhaul of NoFF and trauma services. The local logistics was restructured to procure “Trochanteric grip plates” within 24 h to provide mandated quality of care in an effort towards improving patient experience/outcomes.

SNoFF are rare injuries and its diagnosis is either delayed or missed in at least 20 per cent of the cases on initial evaluation. The non-availability of additional implants readily on the shelf coupled with lack of a trauma bed at the tertiary centre resulted in an unacceptable delay from admission to definitive surgery. The authors recommend that all DGHs have a mechanism/emergency procurement procedure system in place to obtain the required instrumentation kits rapidly through a sharing scheme with regional hospitals or through implant vendor to avoid unacceptable delays to surgery.

The purpose of this paper is to present an improved methodology for design of custom‐made hip prostheses, through integration of advanced image processing, computer aided design (CAD) and additive manufacturing (AM) technologies.

The proposed methodology for design of custom‐made hip prostheses is based on an independent design criterion for each of the intra‐medullary and extra‐medullary portions of the prosthesis. The intra‐medullar part of the prosthesis is designed using a more accurate and detailed description of the 3D geometry of the femoral intra‐medullary cavity, including the septum calcar ridge, so that an improved fill and fit performance is achieved. The extra‐medullary portion of the prosthesis is designed based on the anatomical features of the femoral neck, in order to restore the original biomechanical characteristics of the hip joint. The whole design procedure is implemented in a systematic framework to provide a fast, repeatable and non‐subjective response which can be further evaluated and modified in a preplanning simulation environment.

The efficacy of the proposed methodology for design of custom‐made hip prostheses was evaluated in a case study on a hip dysplasia patient. The cortical bone was distinguished from cancellous in CT images using a thresholding procedure. In particular the septum calcar ridge could be recognized and was incorporated in the design to improve the primary stability of the prosthesis. The lateral and frontal views of the prosthesis, with the patient's images at the background, indicated a close geometrical match with the cortical bone of femoral shaft, and a good compatibility with the anatomy of the proximal femur. Also examination of the cross sections of the prosthesis and the patient's intra‐medullary canal at five critical levels revealed close geometrical match in distal stem but less conformity in proximal areas due to preserving the septum calcar ridge. The detailed analysis of the fitting deviation between the prosthesis and point cloud data of the patient's femoral intra‐medullary canal, indicated a rest fitting deviation of 0.04 to 0.11 mm in stem. However, relatively large areas of interference fit of −0.04 mm were also found which are considered to be safe and not contributing to the formation of bone cracks. The geometrical analysis of the extra‐medullary portion of the prosthesis indicated an anteversion angle of 12.5 degrees and a neck‐shaft angle of 131, which are both in the acceptable range. Finally, a time and cost effective investment casting technique, based on AM technology, was used for fabrication of the prosthesis.

The proposed design methodology helps to improve the fixation stability of the custom made total hip prostheses and restore the original biomechanical characteristics of the joint. The fabrication procedure, based on AM technology, enables the production of the customized hip prosthesis more accurately, quickly and economically.

Fracture experiments on real human bodies to examine the protected positions and protective devices for the development of protective clothing to manage fractures is exceedingly difficult. Thus, the experimental design will have limitations, more of which are imposed if subjects are elderly people. To circumvent these limitations, this study proposes a finite element model of the hip joint in elderly women with virtual impact simulations that can replace actual fall and impact tests, and examine the positions and characteristics of fractures resulting from taking a fall.

The hip joints were modeled after the average horizontal surface size and cross-sectional shapes of the lower extremities (waist to knee) in 439 elderly Korean women in that age group. The model was composed of bones, cartilages, and soft tissue.

The fracture was examined by comparing the maximum stress on the hip joint by applying a point force to its adjacent surface. The vulnerable part in the hip joint neck with a high risk of fracture risk on an impact could be determined and used to set the protective device attachment position.

It is significant that this study has developed a partial model of the human body that can be used for a relatively simple simulation by minimizing the highly complex human body as much as possible. Furthermore, the model is easily applicable to the designing of protected positions and protective devices for the development of special clothing, for hip joint fracture prevention.