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Teijin Nakashima Medical designs joint prostheses, trauma devices, and optimal surgical instruments for each individual implant.
To design these joint prostheses, we pursue the optimal shape by measuring configuration of Japanese patients so as to achieve the reconstruction of the joint function.
In addition, we calculate the mechanical strength obtained as a structure and the effects on the bones and surrounding tissue when the joint prosthesis is inserted.
Based on a “❻validation by collaborated clinical and medical engineering”, we review the effects of design on function in an effort to improve joint function.
We conduct safety evaluation test and functional verifications on prototypes made in-house.

What are the features of Teijin Nakashima Medical's design?

We design surgical instruments to fit in individual surgical procedures and new highly-functional implants via various validations.
In order to contribute to the improvement in the patient’s Quality of Life, we are trying to design products that meet doctor requirements by having doctors, sales persons, designers, production groups, QA groups, and RA groups collaborate with each other.

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Evaluation of effectiveness and safety

To sell a medical device, marketing approval must be obtained from the Ministry of Health, Labor and Welfare.
Joint prostheses and trauma devices, which qualify as “specially controlled medical devices,” require supporting documents that prove the safety, durability, performance, and availability via various verification activities.
Evaluation by non-clinical or clinical trial is required especially in the development of new materials and new joint prostheses, which we submit to the Ministry of Health, Labor and Welfare for approval.
Once approval has been granted, we can sell them as medical devices.

How does Teijin Nakashima Medical evaluate the effectiveness and safety of its products?

To guarantee the effectiveness and safety of products, we conduct about 10 to 20 kinds of tests including evaluations of materials and functions under official standards like ISO, ASTM, JIS, and so on.
As for joint prostheses, we use knee or hip simulators that recreate actual joint motion for functional evaluations in order to prove effectiveness and safety.

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The whole manufacturing process from machining to mirror-polishing (finishing) is done by Teijin Nakashima Medical.
Though, in the beginning, we polished products by hand, which made use of the craftsmanship experience accumulated in propeller manufacturing, today, with the installation of cutting-edge processing machinery like fully-automatic grinding machines, more sophisticated manufacturing is achieved.

What are the features of Teijin Nakashima Medical's manufacture?

The highlight of our manufacturing work is that we can meet the various needs of doctors with highly sophisticated equipment and techniques.
Since almost all manufacturing processes are done in-house, it is possible to manufacture the optional products and customized products for each individual patient within a short period of time.

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Inspection & Sterilization

Final inspections are conducted on finished products. They serve to validate processing accuracy and ensure that products are manufactured according to drawings.
All implants are cleaned and sterilized.
The representative sterilization methods are EOG (ethylene oxide gas) sterilization and Gamma sterilization.
EOG sterilization is done at Teijin Nakashima Medical, while Gamma sterilization is outsourced.
There are some cases where products are sterilized at hospitals.

What part do you put a greater care to maintain the quality and safety of products?

We are committed to carefully inspecting all products one by one by checking appearances and dimensions. When we have questions, we can confirm directly and immediately with the design team.
All members of the sterilization and inspection team devote special care to inspecting all products, so that we can feel safe and reassure should we have to use them for our own families.

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The products made by Teijin Nakashima Medical are ultimately inserted in a patient’s body.
In the implantation of artificial joints, it is very important to install the products in the appropriate position.
This is achieved by osteotomy based on the bone geometry of the individual patient.
We are committed to
 ・developing and manufacturing surgical instruments that fit with surgical procedures;
 ・researching and developing surgical instruments for each individual patient (such as “personalized cutting guide”), and;
 ・developing computerized preoperative planning systems.
These efforts serve to ensure the best surgery for each patient.

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Validation by collaborated clinical and medical engineering,

As a typical example of validation, we conduct motion analyses. Though the joint function involves motion, a conventional clinical evaluation is done only by X-ray (2D, still image), which does not allow a proper evaluation of motion.
The motion analysis evaluates joint motion in three dimensions by taking continuous X-rays. We are aiming at higher functioning of artificial joints by validating the biological joint motion after joint replacement surgeries, and reflecting those results in actual surgical operations and product designs.

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