Status of Bone Allografting in Japan – Nation-Wide Survey of Bone Grafting Performed from 1995 through 1999

Management of regional bone bank during declaration of a state of emergency concerning the COVID-19 in Japan

Bone banks are necessary for providing biological allografts for a series of orthopedic procedures. As nations cope with new realities driven by the 2019 coronavirus disease (COVID-19) pandemic, health-care providers, institutions, and patients share a particular concern about the effect of COVID-19 on organ donation and transplantation. Here, we describe the management of the Kitasato University Bone Bank during the state of emergency declared in response to COVID-19. Living donors received pre-operative screening by PCR, and allograft bone from COVID-19-negative donors was cryopreserved as transplantable tissues. The weekly rate of infection gradually increased from February 2–9 to April 5–11 in the dead donor-derived allograft bone-harvesting region covered by the Bank. It is becoming clear that the virus can be transmitted by asymptomatic patients, and that this route may have facilitated the spread of COVID-19. Therefore, the Bank stopped dead donor donation to consider the safety of medical staff. Three recipients received bone allografts following pre-operative COVID-19 screening by PCR. All patients were asymptomatic after bone allograft. Our experience may provide helpful information for the management of tissue banks.

Revision total hip arthroplasty - Salvage procedures using bone allografts in Japan

Total hip arthroplasty (THA) and hemiarthroplasty have improved hip joint function of patients suffering from hip disease or trauma with excellent clinical results and long-term survivorship. Conversely, there has been an increase in the number of revision surgeries after THA and hemiarthroplasty due to bone deficiency. The reconstruction of deficient bone remains a challenging problem following THA. While performing revision surgery, we have previously classified the preoperative bone deficiency using X-ray, CT and three-dimensional CT imaging according to location and severity of the deficiencies. We then predicted the shape and amount of the required bone allograft and the type of implant. Due to the accepted reconstruction methods of bone deficiency following revision surgeries, it is important to pre-operatively assess the site and size of the bone deficiency to be repaired in the revision THA (re-THA). Bone allograft makes it possible to repair massive bone deficiency, recover bone stock, and improve long-term implant stability. Performing bone allograft will require a bone bank for harvesting, treating, and storing bone in Japan.

Endemic impact of human T cell leukemia virus type 1 screening in bone allografts

Allograft bone is a widely used as a convenient tool for reconstructing massive bone defects in orthopedic surgery. However, allografts are associated with the risk of viral disease transmission. One of the viruses transmitted in this manner is human T-lymphotropic virus type 1 (HTLV-1), which is found worldwide but is unevenly distributed. The southwestern parts of Japan are a highly endemic for HTLV-1. We investigated the HTLV-1 seroprevalence in candidate allograft donors at the regional bone bank in Kagoshima, Japan during its first 5 years of service. Between 2008 and 2012, we collected 282 femoral heads at the Kagoshima regional bone bank from living donors with osteoarthritis of the hip joint. Among the 282 candidate donors, 32 donors (11.3 %) were seropositive for anti-HTLV-1 antibody; notably, this prevalence is higher than that reported for blood donors in this area. Additionally, to determine if HTLV-1 genes are detectable after processing, we examined the bone marrow of the femoral heads from seropositive donors by conducting PCR assays. Our results confirm the existence of viral genes following the heat treatment processing of the femoral heads. Therefore, it is important to inactivate a virus completely by heat-treatment. Together, our findings highlight the importance of HTLV-1 screening at bone banks, particularly in HTLV-1-endemic areas such as southwest Japan.

A NEW APPROACH TO PARTIALKNEE ENDOPROSTHESIS IN PRIMARY BONE SARCOMAS

Partial knee endoprosthesis to bone sarcomas resections seems to be a good solution to treat this immature skeletal patients. The purpose of this study is to evaluate the functional score in fourteen patients, advantages and the technique indications. Methods: Retrospective analysis was done to assess in this group of patients the functional evolution and the possible complications of the procedure. 14 patients between 10 and 22 years functionally evaluated in Ennekin/ISOLS (International Society of Limb Salvage) criteria, being all of them operated in the same institution by the same surgeon. Were used distal femur and proximal tibia partial endoprosthesis. Results: General analysis demonstrated that the functional results were over than 67 percent (ISOLS criteria) in 78,6 percent of the patients, being considered excellent. 21,4 percent were considered good results, being between 50 and 66 percent. Bone storage was preserved when avoiding the adjacent segment resection. Surgery time was not prolonged in ligament reconstruction. Conclusion: Knee partial endoprosthesis are less damage to bone storage in young patients. The critics about the bad functional results are being supplied by new surgical techniques, excellent rehabilitation protocols, implants technology and the consequent learning curve. This option of treatment permits the preservation of healthy bone and provides the possibility of a revision replacement less aggressive.

Radiological evaluation of allograft reconstruction in acetabulum with Ganz reinforcement ring in revision total hip replacement

BACKGROUND

In revision total hip replacement (THR), cages and rings are commonly used for the reconstruction of bone defects that are due to mechanical loosening of the acetabular cup and migration of the femoral head prosthesis. The purpose of this study was to evaluate the radiological results of the use of Ganz reinforcement rings with bone allografts in acetabular revision THR.

METHODS

We reviewed 30 hips of 28 patients who underwent allograft reconstruction of the acetabulum with a Ganz reinforcement ring in revision THR. The average postoperative follow-up period was 8 years. The position of the acetabular socket was measured on anteroposterior radiographs. Loosening of the acetabular component was defined as a change in the cranial or central direction of the cup or a change in the cup inclination angle at the time of last follow-up. In cases of segmental bone defects in weight-bearing areas, we used two or three strut screws prior to incorporation of the Ganz reinforcement ring to act as struts for the ring. Kaplan-Meier survivorship analysis was performed. The end point was revision surgery done because of defined loosening of the acetabular component at the time of the last follow-up.

RESULTS

All five acetabular components (16.7%) defined as showing aseptic loosening were type D defects (cranio-central defects), but no patient needed revision surgery during the follow-up period. Nine revision surgeries with strut screws for type D acetabular bone defects were performed. The calculated Kaplan-Meier survival rate at 5 years was 96.0%, and the rate at 10 years was 80.2%, using defined loosening of the acetabular component as the end point.

CONCLUSIONS

Allograft reconstruction of the acetabulum with a Ganz reinforcement ring is a useful technique for revision THR. Occasionally, a special technique (the strut screw technique) was required for the reconstruction of type D bone defects.

Current trends in bone grafting and the issue of banked bone allografts based on the fourth nationwide survey of bone grafting status from 2000 to 2004

BACKGROUND

The Japanese Orthopaedic Association Committee on Tissue Transplantation and Regenerative Medicine has conducted a nationwide survey of the status of bone grafting in Japan every 5 years from 1985. We report here the status of bone grafting from 2000 to 2004, show the trends in bone grafting from 1985 to 2004, and draw attention to the issues affecting banked bone allografts.

METHODS

Questionnaires devised by the Committee were sent to all educational and training hospitals (2239 institutions) approved by the Japanese Orthopaedic Association.

RESULTS

Survey responses were obtained from 1263 institutions (56%). Of these, 875 institutions performed tissue transplantation during this period. A total of 163 564 tissue transplantations were performed, and 134 782 (82.4%) of them were bone grafts. Of the bone grafts, 76 015 (56.4%) were autografts, 53 735 (40%) used a synthetic bone substitute, and 4886 (3.6%) were banked bone allografts. The proportion of synthetic bone substitutes increased, and the proportion of autografts decreased year by year. Synthetic bone substitutes were most frequently used for replacement arthroplasty (31%). Fifty percent of banked bone allografts were performed for joint disorders requiring replacement arthroplasty. During this period, 271 institutions performed banked bone allografts, with 210 preserving allografts in their own institutions. Donor selection criteria, processing and preservation methods, and management of the bone bank were not the same in all banks.

CONCLUSIONS

Most bone grafts performed in Japan during the four surveys were still autografts. However, the proportion of autografts decreased, and the proportion of synthetic bone substitutes increased. The number of synthetic bone substitutes and banked bone allografts used for replacement arthroplasty increased significantly. However, the total number of banked bone allografts reported in the fourth survey was still low. Quality control of banked bone allografts and management of bone banks were not satisfactory, although they were improved.

Is retrieval of bone material from multiorgan donors effective enough to cover demand for biostatic bone tissue grafts in Poland?

In Poland there is growing demand for biostatic allogeneic bone transplantation mostly for traumatologic operations and orthopedic reconstructions. The bone material is primarily harvested during postmortem examinations in forensic and pathology laboratories. Nevertheless, the collected amounts are not sufficient, so that material needs to be acquired from alternative sources, such as multiorgan donors. Between 1998 and 2003, 2331 potential donors were registered by the Transplantation Coordinating Center in Warsaw, which was adjusted to 1794 donors who would have been accepted as donors of the bone tissue. Unfortunately, due to denials from family members and public prosecutors, the sample was only 1416 donors, which would cover about 40% of the clinical orthopedic demand in Poland.