Objective To evaluate the effectiveness of Poster Fusion Cage combined with xenogeneic bone graft augmentation for bone defect management in distal radius fractures. MethodsA retrospective analysis was conducted on 20 patients with bone defects complicating distal radius fractures who met the selection criteria and were treated between June 2022 and June 2024. The cohort comprised 2 males and 18 females, aged 54-87 years (mean, 63.3 years). Etiologies included falls in 17 cases, traffic accidents in 2 cases, and crush injury in 1 case. According to AO classification, there were 5 cases of type A, 8 cases of type B, and 7 cases of type C. The interval from injury to operation ranged from 2 to 10 days (mean, 5.8 days). All patients underwent volar plate fixation augmented with Poster Fusion Cage and demineralized xenogeneic bone matrix grafting. The operation time, intraoperative blood loss, fracture healing time, and postoperative complications were recorded. Radiographic parameters, including radial height, volar tilt, and ulnar deviation, were measured on standardized X-ray films obtained immediately postoperatively and at last follow-up, and whether secondary reduction loss occurred was judged. At last follow-up, wrist range of motion (extension, flexion, radial deviation, ulnar deviation, pronation, and supination) and grip strength (expressed as a percentage of the contralateral side) were measured. Wrist function was assessed using the Disabilities of the Arm, Shoulder, and Hand (DASH) score and Patient-Rated Wrist Evaluation (PRWE) score. Results The operation time was 70-200 minutes (mean, 116.4 minutes), and the intraoperative blood loss was 10-80 mL (mean, 36.5 mL). All surgical incisions healed by first intention, with no neurovascular complications documented. All patients were followed up 9-12 months (mean, 11.6 months). All fractures healed normally, with a healing time of 8-14 weeks (mean, 9.95 weeks). No significant difference was observed in radial height, volar tilt, or ulnar deviation between immediate postoperative and last follow-up (P>0.05). All fractures achieved satisfactory reduction, with no secondary loss of reduction or implant failure occurring during follow-up. At last follow-up, the range of motion of the affected wrist joint was 60°-65° (mean, 62.5°) in extension, 67°-75° (mean, 71.1°) in flexion, 18°-23° (mean, 20.4°) in radial deviation, 28°-33° (mean, 30.1°) in ulnar deviation, 69°-80° (mean, 74.7°) in pronation, and 69°-82° (mean, 75.6°) in supination. Grip strength recovered to 75%-85% (mean, 80%) of the contralateral side. Functional scores showed a DASH score of 5-15 (mean, 9.4) and PRWE score of 8.0-12.5 (mean, 10.2). Conclusion The combination of Poster Fusion Cage and xenogeneic bone graft augmentation provides a safe and effective treatment for bone defects in distal radius fractures.