Postoperative loss of correction is a concern in cases of distal radius fracture with bone loss after surgery. The purpose of this study was to evaluate the usefulness of a β-tricalcium phosphate (β-TCP) with unidirectional pore structure (Affinos®: Kuraray Co., Ltd, Tokyo, Japan) with internal fixation in patients with bone defects during the correction of distal radius fractures. Thirty-nine patients (40 radii) treated between 2016 and August 2020 were included in the study. There were 8 males and 31 females; the mean age was 70.9 (32-88). The mean postoperative observation period was 14.6 (3.4-24) months. The bone defect that occurred in the surgery was filled with Affinos® and fixed with a locking plate. Radial inclination (RI), volar tilt (VT), and ulnar variance (UV) were evaluated after the operation and at the final observation. The start of absorption and the completion of replacement to the host bone of Affinos® were also evaluated. There were no complications associated with grafts of Affinos®. The mean time of translucent findings around artificial bone was 1.85 (0.5-6) months, and that of complete resorption was 10.6 (1.5-16.5) months after surgery. The mean RI was 21.82° after surgery and 21.16° at final observation. The mean VT was 8.54° after surgery and 8.50° at final observation. The mean UV was -0.3 mm after surgery and 0.5 mm at final observation. Affinos® was resorbed relatively early, and host bone formation was observed. Filling of unidirectional pore structure β-TCP with internal fixation showed favorable outcomes in the surgery of distal radius fractures with bone defects.
Keywords: bone graft; fracture; radius; surgery; unidirectional porous β-tricalcium phosphate.