AGN1 local osteo-enhancement procedure for treatment of contralateral proximal femur bone loss in post-menopausal osteoporosis during acute hip fracture repair with two-year follow-up
Christian Fang, Evan Fang, Dennis King-Hang Yee, Tak-Wing Lau, Jake Cheung, Frankie Leung
Purpose: AGN1 local osteo-enhancement procedure (LOEP) is an emerging surgical treatment intended to address the pathology of osteoporosis of the hip by increasing mechanical strength. This prospective single-centre study assessed the first cases in which AGN1 LOEP was performed on contralateral, unfractured hips during the same operative session as index hip fracture surgery.
Methods: The study was designed to enrol up to 20 post-menopausal women older than 65 who had recently suffered a hip fragility fracture requiring surgical repair. Immediately following fracture repair, the femoral enhancement site was prepared and filled with AGN1, a triphasic and osteoconductive implant material that is resorbed and replaced with bone in situ. Patients followed the standard care map for geriatric hip fracture both in hospital and post-discharge. Patient demographics and procedural data were collected, including peri-operative adverse events (AEs) and the additional operation time needed for AGN1 LOEP.
Results: A cohort of 13 patients were treated with AGN1 LOEP. The treatment, including patient repositioning, increased the operation time by an average of 24.9 minutes. The length of hospital stay and time to weight bearing were not affected by LOEP. None of the AEs reported showed a causal relationship with the AGN1 LOEP device or treatment. There was one death due to ischaemic heart disease and unrelated to the study material. Serial X-rays demonstrated complete implant material resorption and new bone formation in all patients by 12 months.
Conclusion: Our study suggests that AGN1 LOEP is feasible and well tolerated as a concomitant, surgical treatment of the contralateral hip in patients undergoing surgery to treat a first hip fracture. LOEP treatment altered neither the treatment nor the rehabilitation pathways for patients. Promising findings support the continued use and further clinical investigation of AGN1 LOEP as a treatment option for patients at risk of a secondary contralateral hip fracture.
KEY WORDS: Osteoporosis, femoral strength, local osteo-enhancement procedure (LOEP), bone mineral density.