Surgical Repair of Acetabular Fracture Using Unidirectional Porous β-Tricalcium Phosphate

Abstract

We report a case of an acetabular fracture treated using a unidirectional porous β-tricalcium phosphate artificial bone (Affinos®) to surgically repair bone defects. An 82-year-old man sustained an acetabular fracture on the left side and presented with shock on arrival along with impaired vital signs and systolic blood pressure. Upon stabilization, we performed an open reduction and internal fixation. However, there were significant bone defects, which were then fixed using Affinos® (both blocks and granules), an artificial β-tricalcium phosphate bone with a porosity of 57% (pore size: 25–300 μm), characterized by a novel unidirectional porous structure. By 18 months postoperatively, the patient was able to perform stair climbing and absorption and bone fusion around the artificial bone were observed. Affinos® has a frost-like structure, which endows it with good tissue-invasive properties because of the capillary effect. Moreover, it has excellent osteoconduction capability. In this case, both Affinos® blocks and granules showed good affinity, absorption, and bone substitution. Further prospective studies are required to confirm our findings.

Unidirectional porous beta-tricalcium phosphate and hydroxyapatite artificial bone: a review of experimental evaluations and clinical applications

“…Observations at 12 and 24 months confirmed that replacement of the material with the patient's own bone had progressed over time [10]. Although no absorption was seen at 3 months when blocks and granules were used for a large bony defect during plate fixation for pelvic fracture, they were completely replaced with the patient's own bone at 18 months [14]. Another institution also reported favorable outcomes with the use of Affinos ® for bony defects during plate fixation in distal radius fractures [15].…”

A Novel Unidirectional Porous β-tricalcium Phosphate Bone Substitute in Orthopedic Surgery: A Technical Note and Case Illustrations

“…Affinos is also expected to present balanced absorption and regeneration similar to autologous bone from an early stage in clinical applications. However, limited clinical application studies have been reported so far [7][8][9][10][11][12][13]. Here, we report the benefits of Affinos as an absorbable material for bone regeneration by introducing clinical application cases in various fields of orthopedic surgery.…”

How much platelet-rich plasma can be soak-loaded onto beta-tricalcium phosphate? A comparison with or without a unidirectional porous structure

“…UDPTCP can induce osteogenesis as fast as UDPHAp in the same animal model with an improved balance of material absorption 19) . In grafts used at fibular resection sites in spinal surgeries, UDPTCP results in fewer residual bone defects than spherical porous β-TCP (SPTCP) 20) , and the absorption of the material and replacement with a new bone contribute to a strong recovery at the graft site 21,22) . β-TCP plays a role in the scaffold and mechanical envi-ronment, while PRP plays a growth factor.…”