Unidirectional Porous β-Tricalcium Phosphate: A New Bone Filling Substitute for Treatment of Distal Radius Fracture in the Elderly Population

Background: A new beta-tricalcium phosphate with unidirectional pore structure (UDPTCP), Affinos^® (Kurray, Okayama, Japan), has been in clinical use since 2015. To date, there have been only a few clinical studies using this material. We report here the first clinical study for distal radial fracture in the elderly population treated with UDPTCP.

Methods: Consecutive patients aged 65 years or older with dorsally displaced unstable fracture of the distal radius (n = 36) were treated operatively in our department. Following reduction of the fracture site, a 7 mm size cube of UDPTCP was placed in the gap of the bony defect and the fracture stabilized with mono-axial or poly-axial type locking plates and screws. Remodeling of the UDPTCP was evaluated by plain radiograph and clinical outcomes were also assessed.

Results: UDPTCP was significantly resorbed at 2 months after surgery, both at the center and periphery of the material. Complications were only observed in the post-operative period. Significant correction loss of radial alignment was seen in patients stabilized with poly-axial locking plate. The clinical outcome in all cases was excellent.

Conclusions: Block UDPTCP is a safe and convenient material for the treatment of distal radius fracture and is replaced within a suitable time period after grafting into the fracture site. UDPTCP and stable internal fixation is therefore a reliable strategy for restoring and preserving anatomical position, especially in the elderly population.