Unlinked total elbow arthroplasty (TEA), which has no mechanical connection between the humeral and ulnar components, has theoretical advantages based on its near-normal elbow kinematics and the preservation of bone stock. Unlinked TEA is appropriate only for patients who have limited bone loss or limited deformity and good ligamentous function. This is because postoperative instability has been a major complication of unlinked prostheses. The concept and goal of unlinked TEA is to share the loading stress on the bone implant interface with the surrounding tissues. Although the loosening rate of unlinked prostheses theoretically should be lower than that of linked prostheses (which have a mechanical connection between the humeral and ulnar components), there is no clear evidence that unlinked TEAs are superior to linked TEAs in this respect. However, we believe that primary TEA should be performed using an unlinked TEA, especially for younger patients, because revision surgery for unlinked TEA results in longer prosthesis survival than revision surgery for linked TEA. Improvement of the design of unlinked prostheses and the introduction of less invasive surgical techniques are required to reduce postoperative instability.

In this study, we investigated the correlations between biochemical and hematological test results obtained using microliter-scale fingertip blood samples collected with a newly developed blood collection device and those obtained using conventional venous blood. Eighty volunteer subjects were enrolled in this study. Blood samples were drawn from the fingertip of the ring finger by a single puncture, and 60-µL samples were promptly and accurately aspirated into a blood collection chip. Then the chip was tightly sealed in a chip container and was shaken to mix the contents without dispersion. For biochemical tests other than that for HbA1c, blood was collected without anticoagulant and centrifuged to obtain 15 µL of serum which was then diluted with 190 µL of physiological saline for the assay. For hematological tests and the test for HbA1c, the sample was assayed with blood collected using EDTA-2 K. Good correlations were obtained between the test results of the assay using fingertip blood and that using venous blood. The correlation coefficients were ≥0.97 for TG, T-CHO, HDL-C, LDL-C, GLU, ALT, γ-GTP, UA, BUN, and HbA1c and ≥0.95 for WBC, RBC, Hgb, and Hct. These results suggest that our microliter-scale blood testing system is comparable to assays using venous blood and may be useful as a rapid and simple test to determine basic clinical parameters that are close to the reference intervals.

Graft-versus-host disease (GVHD) is a major contributor to early and late morbidity and mortality after allogeneic stem cell transplantation. Despite results from a randomized controlled trial demonstrating an increased risk of chronic GVHD with use of growth factor-mobilized peripheral blood stem cells (PBSC) compared with bone marrow, PBSCs are the most widely used graft source in allogeneic transplantation for hematologic neoplasms in the U.S. This lecture will review established, recent, and novel strategies for GVHD prevention in unrelated donor PBSC transplantation and will highlight ongoing clinical research at Fred Hutchinson Cancer Research Center. Clinical trials aimed at defining standard-of-care GVHD prophylaxis after myeloablative and nonmyelablative conditioning will be presented. In addition, novel pharmacologic agents and graft manipulation strategies under investigation will be discussed. (Presented at the 1962nd Meeting, May 12, 2018)