Evaluating augmentation with calcium phosphate cement (chronOS Inject) for bone defects after internal fixation of proximal tibial fractures: A prospective, multicenter, observational study.

INTRODUCTION Managing subchondral bone defects in proximal tibia fractures after plateau reduction is an important consideration. ChronOS Inject is a recently developed calcium phosphate bone substitute that shows relatively fast osteointegration. HYPOTHESIS Using chronOS Inject during internal fixation of proximal tibial fractures provides a satisfactory treatment option that is both clinically and radiologically safe. PATIENTS AND METHODS Patients enrolled in this study were treated with chronOS Inject bone void filler, during internal fixation of proximal tibial fractures. Patients were evaluated preoperatively and at 6 weeks, 6 and 12 months postoperative. Radiographic union was assessed using plain films supplemented by CT scans. Pain, function and adverse events were collected at all visits. A total of 36 patients were enrolled in the study and treated according to a predetermined protocol. Seven of the 36 patients (19.4%) were lost to follow-up. RESULTS Successful radiographic union was achieved in 27/29 (93.1%) of patients at final follow-up. Articular subsidence of>2mm only occurred in one patient. Statistical analysis showed significant improvements both in leg pain and knee function. Progress in knee function was observed in 93.1% (27/29) of patients from 6 weeks to 12 months. No product-related complications were reported. CONCLUSIONS Successful union was achieved based on radiographic criteria as well as clinical outcomes. When managing bone defects after internal fixation of proximal tibial fractures, the use of chronOS Inject resulted in significant improvement of knee function and reduction of leg pain. LEVEL OF EVIDENCE Level IV, prospective observational study.