The artificial hip joint developed by a Kyocera Corp. subsidiary has been increasingly used for surgeries to treat hip osteoarthritis and fracture, with the number of cases reaching 10,000 in the two years since its launch in October 2011, company officials said.
Given that doctors perform about 50,000 hip surgeries per year in Japan, the surging popularity of Aquala Liner by the Osaka-based Kyocera Medical Corp. is exceptional, they said.
The device is popular among doctors who want to reduce the risk of re-operation, as it is designed to last longer than conventional products by giving special coating on the interlocking section supporting the upper body, they said.
In Japan's artificial hip joint market, two U.S. companies—Zimmer Holdings Inc. and Stryker Corp.—have been dominant. Kyocera Medical aims to be the leader in the domestic market in fiscal 2015, while aiming to launch the product in Europe and the United States in the next few years.
The company has also been developing an artificial knee joint, aiming to gain the approval of the Health, Labor and Welfare Ministry for a launch in 2015 or later.
Conventional artificial hip joints would create wear debris if used over a long period of time as the devices are worn down. The immune system then tries to remove the debris and that immune reaction melts bones around the artificial joints, loosening the devices.
Aquala Liner reduced the wear debris to less than 10 percent of the conventional products by covering the surface of "liner," which is embedded in the pelvis to be used in parts connecting to the femur, with special polymer.
Some conventional artificial hip joints need to be replaced in about 10 years, while Aquala Liner is expected to last for at least 20 years, they said.
"Patients' scope of activities will expand, allowing them to participate in activities such as golf and overseas travels which they had given up," said Yoshio Takatori, professor at University of Tokyo graduate school of medicine, who jointly developed the product.