Image-guided periprosthetic bone graft injection for aseptic loosening: a novel IR approach and alternative to orthopedic surgical revision

Abstract Purpose To demonstrate the safety and efficacy of percutaneous bone graft injection as a minimally invasive alternative to surgical revision for the treatment of aseptic prosthetic stem loosening. Methods A retrospective review of seven patients (Mean age: 54 years; 57%F, and 43%M) was performed to assess improvement in ambulatory symptoms following fluoroscopically guided periprosthetic bone graft injection. All patients presented with ambulatory pain and demonstrated radiographic periprosthetic osteolysis consistent with aseptic hardware loosening. Before treatment, patients were assessed with a numeric pain scale (NPS), ranging from 0 to 10, to quantify the degree of debilitation. Using fluoroscopy, a large gage bone biopsy needle was positioned within the periprosthetic lucency and confirmed with the injection of contrast. Under direct fluoroscopic guidance, regenerative bone graft substitute (CaSO 4 –CaP0 4 ) was injected into the periprosthetic osteolytic cavity. Patients were subsequently discharged on the day of the procedure. Patients were followed in the outpatient setting through post-procedural NPS assessment. Results At baseline, all patients demonstrated a mean periprosthetic osteolytic cavity of 5.6 mm and a mean NPS score of 5 ± 2.7. Following intervention, the mean periprosthetic osteolytic cavity was reduced to 0.3 mm, with a significant decrease in ambulatory symptoms and a mean NPS score of 1.7 (p < 0.001). Outcome pain reduction was directly correlated to post-procedural periprosthetic lucency. Three patients (43%) required open surgical revision due to progressive severe osteolysis or posttraumatic fracture. One patient (14%) required a second injection of bone graft for residual cavity. Overall, 57% of patients had demonstrated a favorable response with near complete resolution of aseptic loosening and a significant decrease in ambulatory symptoms. There were no acute or latent complications due to bone graft injection. Conclusion Image-guided percutaneous bone graft injection is a minimally invasive alternative to surgical revision for the treatment of aseptic prosthetic stem loosening. The bone graft media is a scaffold for osteoblastosis and periprosthetic osteogenic repair, potentially extending the longevity of the prosthesis. A larger prospective study is recommended for further evaluation.