• The Japanese Society of Shoulder Function Research
• Introduction of reverse shoulder arthroplasty to Japan

Introduction of reverse shoulder arthroplasty to Japan

Eiji Itoi

In Japan, all medical devices and drugs must first be reviewed by the Pharmaceuticals and Medical Devices Agency (PMDA) before use, and a clinical trial in Japan is required for review. Reverse shoulder arthroplasty (RSA) was the first device in Japan to be approved for use in the field of orthopedic surgery without conducting clinical trials, and the Japanese Orthopedic Association (JOA) and the Japan Shoulder Society (JSS) play an important role in the introduction of RSA to Japan.

Until RSA was approved, the shoulder prosthesis mainly used in Japan was the total shoulder arthroplasty (TSA), which anatomically replaces the humeral head. When shoulder arthroplasty is performed in patients with rotator cuff dysfunction accompanied by destruction of the glenohumeral joint, clinical outcomes are poor. Thus, the use of TSA is limited. The RSA was developed in France in the 1980s as a shoulder prosthesis that can be used in cases where the rotator cuff function is impaired and the joint is destroyed. Since then, RSA has improved, and in the 2010s, it was reported that even 10 years after surgery, good results were achieved in > 90% of cases. The use of RSA has already begun not only in Europe and the United States but also in Asian countries such as South Korea (2006) and China (2008). The JSS submitted a request for early approval of the RSA to the Medical Device Review and Management Division, Pharmaceutical Safety and Health Bureau, Ministry of Health, Labor and Welfare, but the request was not accepted. Tornier and Zimmer applied PMDA for the domestic use of RSA. I also participated in this review as a member of the PMDA expert committee. As the RSA was considered a new device because its concept and shape were different from those of the TSA, it was necessary to conduct clinical trials in Japan to investigate its safety, similar to other new devices. Alternatively, they are required to submit clinical data at the same level as domestic clinical trials conducted overseas. However, neither the company conducted a clinical trial nor submitted sufficient data to meet the requirements, and the application was rejected.

Against this background, at the general meeting of the councils held the day before the JOA annual meeting, a council stated that they would like the JOA to lobby the Ministry of Health, Labor and Welfare for the immediate use of RSA in Japan. I then received a phone call from Prof. Yukihide Iwamoto, president of the JOA (Photo 1). The content of the call was, “Following the remarks made by the board of councils, President Iwamoto directly discussed RSA approval with officials from the Ministry of Health, Labor and Welfare. They permitted this exception by creating guidelines for its use. A new working group for applications of the RSA was established in the JOA. There are several candidates to serve as members of the working group, but ultimately, I would like to select a member selected by JSS.” This matter was discussed by the Board of Directors of the JSS, who decided to select members from the JSS for the working group. An RSA guideline creation committee was established by the JOA Implant Committee, headed by Director Yoshitaka Matsusue (Photo 2). Dr. Naoki Suenaga, Dr. Hiroyuki Sugaya, Dr. Yasuaki Nakagawa, Dr. Minoru Yoneda, and Kenji Takagishi (Chairman) were selected from the JSS as committee members (Photo 3). The committee researched papers and discussed them many times, and I consulted with the PMDA to carefully create guidelines. President Iwamoto told me, “I have heard from orthopedic surgeons overseas that serious problems with RSA occur overseas, but they are rarely reported. Therefore, we need to be careful when creating guidelines to prevent such problems." (Photo 4). At that time, the JSS secretariat was located in the Gunma University Orthopedics Department; therefore, doctors from the upper extremities group of the Gunma University Orthopedics Department ( late Dr. Tsutomu Kobayashi, Dr. Atsushi Yamamoto, Dr. Hitoshi Shitara, and Dr. Tsuyoshi Ichinose) organized the data and analyzed papers on RSA (Photo 5). As mentioned above, because the RSA was the first medical device to be approved without a clinical trial, all decisions had to be considered and decided upon by a working group. It has been decided that it is mandatory to attend an RSA training course to perform the RSA. Eligibility for this course was certified by the JOA and had experience in 10 or more cases of humeral head replacement or shoulder arthroplasty, and 50 or more rotator cuff repairs. Furthermore, registration of all cases was required for five years after the approval of the RSA. The RSA guidelines drafted by the working group were approved at a JOA board meeting in May 2013 and submitted to the PMDA. This matter was then discussed by the Council of the Ministry of Health, Labor, and Welfare. Because this RSA was the first device to be approved without clinical trials, I attended the council with PMDA officials and explained the necessity of the RSA. I remember one committee member asking, “I would like to know why the approval was delayed in Japan even though it has been approved in other developed countries.” “I think it's because the manufacturer didn't conduct a clinical trial. If this implant is approved, many patients with shoulder joint dysfunction will be free from this disability." I answered. The RSA was approved after deliberation.

• Photo 1. Prof. Yukihide Iwamoto
  Prof. Iwamoto, who was the president of the Japanese Orthopedic Association, held discussions with the Ministry of Health, Labor and Welfare, paving the way for approval of reverse shoulder arthroplasty in Japan.
• Photo 2. Prof. Yoshitaka Matsusue
  He participated in the creation of guidelines as a director in charge of the Implant Committee of the Japanese Orthopedic Association, and served as a liaison with the Board of Directors of the Japanese Orthopedic Association.

• Photo 3. Dr. Naoki Suenaga, Dr. Hiroyuki Sugaya, Dr. Yasuaki Nakagawa, Dr. Minoru Yoneda, and Kenji Takagishi were selected from the Japan Shoulder Society as menbers of the guideline creation committee.

• Photo 4. Prof. Iwamoto and me He gave me a lot of advice.

• Photo 5. From the second person on the left: Dr. Atsushi Yamamoto, the late Dr. Tsutomu Kobayashi (secretary general of the Japan Shoulder Society at the time), Takagishi, and Dr. Hitoshi Shitara.

I am confident that if RSA can be performed safely in accordance with these guidelines, a path will be established to apply surgical devices at the initiation of academic societies.

The next issue was establishing a 5-year all-RSA case registration system, as described in the guidelines. However, it was difficult to begin registration within the JSS because of experience and manpower issues. Therefore, we decided to request the Japanese Society for Replacement Arthroplasty (JSRA), which has already conducted postoperative registrations for TKA and THA. During the 44th JSRA Annual Meeting held in Okinawa, we consulted the Japanese arthroplasty registration system committee advisor Takashi Nakamura, Professor Emeritus of Kyoto University (Photo 6), and committee chairman Haruhiko Akiyama, Professor of Gifu University (Photo 7). They accepted the RSA registration at the JSRA office. To begin registration, all hospitals where RSA would be performed had to be registered, and each hospital had to receive approval from the Institutional Review Board (IRB). Each hospital was selected based on an IRB approved by the Gunma University Hospital.

• Photo 6. Prof. Takashi Nakamura
  He was instrumental in registering reverse shoulder arthroplasty as a committee advisor of the Japanese arthroplasty registration system.
• Photo 7. Prof. Haruhiko Akiyama
  As the chairman of the arthroplasty registration committee, I received advice on IRB registration, hospital registration, and registration form creation, etc. After registration began, I received many objective opinions about the status of RSA usage from the perspective of the registration committee.

The use of RSA began in April 2014, and the JOA was required to ensure that RSA was performed safely and in compliance with the guidelines. Therefore, the RSA Operation Committee (chaired by Takagishi) was established within the JSS, and Drs. Sugaya, Nakagawa, Yoneda, Hiroyasu Ikegami (Photo 8), and Atsushi Yamamoto (Photo 8) were responsible for the work related to the registration system. On April 5th, the Ethics Committee of the JOA approved the clinical research for RSA registration, and clinical research directors or collaborators were required to undergo an ethical review by the medical institution to which they belonged. The ethics application for RSA registration was approved as an epidemiological study by the Gunma University School of Medicine and posted on the JSRA website on May 7th. On June 19th, I received a message from Dr. Akiyama saying, “The website of the JSRA has been updated, and RSA registration is now available. Please inform all the JSS members.” The JSRA office is located in Kyoto University's Department of Orthopaedic Surgery. After the registration system started working, we received information from Dr. Nakagawa of Kyoto University.

• Photo 8. Prof. Hiroyasu Ikegami, Dr. Atsushi Yamamoto
  After approval from the Ministry of Health, Labor and Welfare, the Reverse Shoulder Arthroplasty Operation Committee was established, and in addition to Dr. Yoneda, Dr. Nakagawa, and Dr. Sugaya, Dr. Hiroyasu Ikegami and Dr. Atsushi Yamamoto (secretary general of the Japan Shoulder Society at the time) joined as members.

Because participants in the RSA training course had to be certified surgeons, we asked each manufacturer to contact the RSA Operation Committee and submit a list of participants before the course. We asked the JOA secretariat to confirm certified surgeons’ qualifications. At the beginning of the training course, an Operation Committee member of the operation committee was required to explain the guidelines. In October 2014, Dr. Eiji Itoi replaced the director of the RSA Operation Committee (Photo 9).

• Photo 9. Prof. Eiji Itoi

According to a 2014 report of an arthroplasty survey conducted by the JSRA, 657 cases of RSA were registered in 2014, the first year of RSA use. As of July 2015, 1238 cases of RSA procedures had been performed, and 685 cases were registered (registration rate, 55%). Subsequently, the registration rate did not increase, and it was necessary to improve it. The committee collected data from manufacturers, examined the registration rates of individual doctors, and issued warnings to doctors with low registration rates to encourage their registration. Additionally, the JSRA questioned whether the guidelines were being followed as there were registered patients under the age of 50. The request to comply with the guidelines was communicated several times to all participants. To complete the registration of all cases in five years, Takagishi asked each manufacturer to report the number of RSA procedures performed and the hospitals involved, and reported this to the Operation Committee and the board of councils without disclosing the names of the operators and hospitals. At the same time, he reported the contents of the training course, the number of RSA performed, and the registration rate to the board of directors of the JOA. The RSA registration status is reported annually.

As of the end of March 2018, four years after approval, the total number of RSA surgeries was 5966, but the number of reported cases was 3844, resulting in a registration rate of 64.4%. The initially created guidelines were revised three times by the end of 2018 in line with actual clinical use. For cases where indications, age, etc., are not included in the guidelines, but for which there is no better option than RSA, they have launched a system to consult with the RSA Operational Committee. Additionally, in January 2019, the Japanese Society for Fracture Repair requested a change in the standards for surgeons, and the guidelines were revised.

There are fewer reports on the frequency of postoperative RSA complications in Japan than in other countries. Furthermore, there are no reports of major medical errors related to RSA in Japan. This is proof that the guidelines first created by the JOA working group, which are made up of selected members of the JSS, are excellent, and that many members have complied with them.