Cranioplasty with Porous Hydroxyapatite Custom-Made Bone Flap: Results from a Multicenter Study Enrolling 149 Patients Over 15 Years.

Background Despite the mixed evidence regarding the effect of decompressive craniectomy in terms of outcome, a tremendous increase in related reports has been observed in the last years. Cranioplasty plays a key role in restoring function and anatomy of the cranial vault. Considering that cranioplasty is not exempt from risks, the identification of the safest technique becomes crucial to achieve better patients' recovery. Porous hydroxyapatite (PHA) has received growing attention for its potential in bony integration. Here we report a multicenter prospective follow-up analysis of 149 patients who underwent cranioplasty with PHA prostheses. In particular, we focus on the incidence of adverse events and implant removal. Method From January 2001 to December 2015 we conducted a prospective multicenter study of 149 patients who underwent cranioplasty with custom-made PHA flaps after decompressive craniectomy for several reasons. The endpoints were the incidence of adverse events after cranioplasty and of related implant removal. Results 66 patients (44%) were treated within 6 months from decompression, and only 2 patients had a bifrontal bilateral reconstruction. Of those, 25 patients reported complications (16.8%), and 9 of them (6% of the whole case series) required removal of the prosthesis. The only significant factor predicting cranioplasty removal was a previous infection. Conclusion Hydroxyapatite for cranial implants is fully comparable to other heterologous materials. It has a biologic potential of bony integration. The risk of explants seems to be significantly higher in second-line patients, data not shown in previous studies. Highlights • PHA seems a good candidate for cranioplasty because HA itself is the main constituent of bone (60%). • Custom-made PHA has excellent biocompatibility because host immune reactions and systemic/local toxicity are absent. • Among the 149 patients, 25 (16.8%) experienced complications. • Prostheses were removed because of infection (n = 7), implant fracture (n = 1), and implant dislocation (n = 1). • Risk of explants seems to be significantly higher in second-line patients: data not shown in previous studies. [ABSTRACT FROM AUTHOR]