Hydroxyapatite Cranioplasty

• Long-Term Series of Custom-Bone Hydroxyapatite Cranioplasty: Outcomes and Survival at 15 Years
• Multicenter study on 2-year outcomes of dual application of hydroxyapatite cranioplasty and a nasoseptal flap following endoscopic endonasal surgery for tuberculum sellae meningiomas or craniopharyngiomas
• Cranioplasty infection in porous hydroxyapatite: Potential antibacterial properties
• Low-cost acrylic cranioplasty using an implant cast on a pre-printed 3D polylactic acid model in a child with a complicated osteolytic extradural hydatid cyst
• Cranioplasty With Hydroxyapatite Implants: A Multidisciplinary Approach of Neurosurgeon and Plastic Surgeons to Improve Surgical Technique and Clinical Outcome
• Outcomes of Hydroxyapatite Bone Cement for Craniofacial Reconstruction in 1983 Patients
• Role of cranioplasty in the management of decompressive craniectomies: Study of the Adolphe de Rothschild Foundation Hospital cohort over 7 years
• Assessment of cranial reconstruction utilizing various implant materials: finite element study

Among alloplastic materials, bioceramics such as microporous and macroporous hydroxyapatite (HA) have been extensively used as a bone graft substitute because the crystalline phase of HA is similar to the bone mineral component.

Morbidity is high following cranioplasty, with over a tenth requiring explantation. Hydroxyapatite and acrylic were associated with reduced risk of all-cause explantation and explantation due to infection. Cranioplasty insertion at three to six months was associated with increased risk of explantation due to infection ¹⁾.

see Custom made cranioplasty of porous hydroxyapatite.

A retrospective study of patients with a hydroxyapatite implant from 2010 to 2014 at our neurosurgical department was conducted. Demographic, surgical and radiological data were studied. A senior neuroradiologist, a staff member neurosurgeon and a resident neurosurgeon independently performed the radiological evaluation. A new software analysis technique was developed to objectively quantify the degree of osteointegration.

Seventeen implants were evaluated with an average patient age of 39 years and a mean follow-up of 155 weeks. Through radiologic evaluation, osseous bridging was deemed higher than 50% in six prostheses and higher than 75% in three. In five patients, no osteointegration could be seen. The remaining patients exhibited sparse signs of osteointegration, estimated between 10 and 50%. Software analysis showed an average osteointegration ratio of 37.4% with a 400-HU filter and 27.3% with a 700-HU filter.

In this small retrospective study of cranial hydroxyapatite implants, osteointegration did occur and to a degree of more than 50% in 1/3 of the patients ²⁾.