Pourquoi peut-on utiliser une plastie en hydroxyapatite pour réparer une perte de substance osseuse de la boîte crânienne chez les enfants : expérience à propos de 19 cas

An innovative 3D hydroxyapatite patient-specific implant for maxillofacial bone reconstruction: A case series of 13 patients

The study aimed to evaluate and discuss the use of an innovative PSI made of porous hydroxyapatite, with interconnected porosity promoting osteointegration, called MyBone Custom® implant (MBCI), for maxillofacial bone reconstruction. A multicentric cohort of 13 patients underwent maxillofacial bone reconstruction surgery using MBCIs for various applications, from genioplasty to orbital floor reconstruction, including zygomatic and mandibular bone reconstruction, both for segmental defects and bone augmentation. The mean follow-up period was 9 months (1-22 months). No infections, displacements, or postoperative fractures were reported. Perioperative modifications of the MBCIs were possible when necessary. Additionally, surgeons reported significant time saved during surgery. For patients with postoperative CT scans, osteointegration signs were visible at the 6-month postoperative follow-up control, and continuous osteointegration was observed after 1 year. The advantages and disadvantages compared with current techniques used are discussed. MBCIs offer new bone reconstruction possibilities with long-term perspectives, while precluding the drawbacks of titanium and PEEK. The low level of postoperative complications associated with the high osteointegration potential of MBCIs paves the way to more extensive use of this new hydroxyapatite PSI in maxillofacial bone reconstruction.

Clinical study on repair of metacarpal bone defects using titanium alloy implantation and autologous bone grafting

Due to various limitations in the use of autologous bone and allogeneic bone in the repair of bone defects, the use of synthetic bone graft substitute has become a hot topic in orthopedic surgery and repair medicine. A total of 53 patients treated for trauma-induced metacarpal bone defects were recruited. These patients were divided into the TiAl₆V₄ titanium alloy implantation group (group A) and the autologous bone graft group (group B). The symptoms of patients in the two groups were closely observed and followed up. The operation time, time to bone fusion, post-surgical pain [visual analog scale (VAS) scores], hand function recovery [total active flexion scale (TAFS) scores] and complications were compared between the two groups. Following surgery, none of the patients had necrosis of fingers or bone non-union. The recovery was rated as excellent and good in up to 91.6% of patients, indicating high clinical efficacy. Compared with the use of autologous bone grafting as the gold standard (group B), there was no significant difference in the excellent and good recovery rate based on TAFS scores at 16 weeks after surgery (91.7 vs. 89.7%, P>0.05), and there was also no significant difference in the incidence of post-operative complications (33.3 vs. 41.3%, P>0.05). The operation time (82.08±6.64 min), time to bone fusion (7.75±1.73 weeks) and VAS scores at 3 days after surgery were all significantly lower in group A than in group B (P<0.05). The values of group B were 104.69±8.63 min, 9.17±2.78 weeks and [5(5, 6)], respectively. However, the hospitalization cost (22,657.8±1,595.4Ұ) was significantly higher than that in group B (14,808.2±2,291.3Ұ; P<0.05). In conclusion, the use of titanium alloy implantation may avoid new injury to the donor site, reduce the operation time and post-operative pain and accelerate bone fusion. Therefore, this method is worthy of popularization for defective bone reconstruction and recovery in the clinic.

Hydroxyapatite ceramic implants for cranioplasty in children: a retrospective evaluation of clinical outcome and osteointegration

INTRODUCTION

Cranioplasty in children is a controversial and challenging issue, since there is still no consensus on the ideal material. Main problems in paediatric age are represented by the child's growing skull, the lower bone thickness and the high incidence of cerebrospinal fluid (CSF) disorders or brain swelling. Autologous bone is still considered the "gold standard". When it is not available, a wide range of alloplastic materials have been proposed. Hydroxyapatite, a ceramic-based derivative, bears a chemical composition very similar to the human natural bone, making this material a valuable alternative to other cranioplasty solutions.

METHODS

All patients implanted with a custom-made porous hydroxyapatite device at Santobono-Pausilipon Hospital in Naples were retrospectively reviewed. A follow-up CT scan of the skull was performed from 1 up to 48 months postoperatively to document the bone ingrowth as well as the osteointegration process. The bone density was measured as according to the Hounsfield scale at the bone-implant interface.

RESULTS

Between 2014 and 2018, 11 patients (7 males, 4 females) underwent cranioplasty with hydroxyapatite ceramic implants (HAP). Patients' age ranged between 3 and 16 years old. Initial aetiology was trauma in most cases. Two subjects were implanted with HAP as primary cranioplasty, 9 as revision surgery following previous cranioplasty failure. Sites of the cranial defect were unilateral fronto-temporo-parietal (N = 8), unilateral frontal (N = 1) and bifrontal (N = 2). Two patients with large bilateral defects received two prostheses. In one of these, the two prostheses were explanted and replaced with two back-up implants (accounting for a total of 15 implants in 11 patients). Osteointegration was measurable for 12 out of 15 implanted devices. The mean percentage was about 51%. There were six asymptomatic prosthesis fractures (40%), all occurring within 6 months from implant. In one case, the bifrontal prostheses were explanted and replaced. This was the only patient who underwent revision surgery.

CONCLUSION

Hydroxyapatite ceramic implants represent a valid alternative to other cranioplasty solutions. Where coaptation occurs correctly, with good osteointegration, implant mechanical resistance increases over time.

Titanium Three-Dimensional Printed Cranioplasty for Fronto-Nasal Bone Defect

OBJECTIVE

To analyze the characteristics and outcome of patients who underwent the insertion of a 3-dimensional (3D) printed titanium (Materialise) cranioplasty.

METHODS

Surgical and clinical data of patients who underwent 3D printed titanium cranioplasty insertion at our institution were retrospectively reviewed.

RESULTS

A retrospective search identified 19 cases of titanium cranioplasty insertion between 2012 and 2018. 12 patients were male (63.2%) and mean age at cranioplasty was 47.4 ± 11.3 years. 9 patients had the cranioplasty inserted during the very same procedure of the craniectomy and 10 at a separate surgical stage from the craniectomy. Median delay from the craniectomy until the prosthesis insertion was 0.6 years, interquartile range (IQR) [0.4, 0.9]. Side of cranioplasty insertion was right in 6 cases and in the midline frontal in 9. Median surface of the implant was 68.1 cm, IQR [53, 125.4]. Median follow-up since the cranioplasty insertion was 1.2 year, IQR [0.4, 2.1]. At data collection, 1 patient was lost to follow-up, 1 had its cranioplasty taken out but, none was reported dead. 6 patients (31.6%) experienced early post-operative complications following the cranioplasty insertion. One patient had its cranioplasty removed 2.5 years after the insertion for tumoral recurrence (hemagiopericytoma) and skin necrosis leading to the plate exposure.

CONCLUSION

3D printed titanium cranioplasty are useful for complex craniofacial reconstruction regardless the etiology of the skull defect. This device is not associated with a higher rate of complication.

Evaluation of neurosurgical implant infection rates and associated pathogens: evidence from 1118 postoperative infections

OBJECTIVE

Various implanted materials are used in neurosurgery; however, there remains a lack of pooled data on infection rates (IRs) and infective bacteria over past decades. The goal of this study was to investigate implant infections in neurosurgical procedures in a longitudinal retrospective study and to evaluate the IRs of neurosurgically implanted materials and the distribution of pathogenic microorganisms.

METHODS

A systematic literature search was conducted using PubMed and Web of Science databases for the time period between 1968 and 2018. Neurosurgical implant infections were studied in 5 subgroups, including operations or diseases, implanted materials, bacteria, distribution by country, and time periods, which were obtained from the literature and statistically analyzed. In this meta-analysis, statistical heterogeneity across studies was tested by using p values and I2 values between studies of associated pathogens. Egger’s test was used for assessing symmetries of funnel plots with Stata 11.0 software. Methodological quality was assessed to judge the risk of bias according to the Cochrane Handbook.

RESULTS

A total of 22,971 patients from 227 articles satisfied the study’s eligibility criteria. Of these, 1118 cases of infection were reported, and the overall IR was 4.87%. In this study, the neurosurgical procedures or disorders with the top 3 IRs included craniotomy (IR 6.58%), cranioplasty (IR 5.89%), and motor movement disorders (IR 5.43%). Among 13 implanted materials, the implants with the top 3 IRs included polypropylene-polyester, titanium, and polyetheretherketone (PEEK), which were 8.11%, 8.15%, and 7.31%, respectively. Furthermore, the main causative pathogen was Staphylococcus aureus and the countries with the top 3 IRs were Denmark (IR 11.90%), Korea (IR 10.98%), and Mexico (IR 9.26%). Except for the low IR from 1998 to 2007, the overall implant IR after neurosurgical procedures was on the rise.

CONCLUSIONS

In this study, the main pathogen in neurosurgery was S. aureus, which can provide a certain reference for the clinic. In addition, the IRs of polypropylene-polyester, titanium, and PEEK were higher than other materials, which means that more attention should be paid to them. In short, the total IR was high in neurosurgical implants and should be taken seriously.

Custom-made hydroxyapatite for cranial repair in a specific pediatric age group (7-13 years old): a multicenter post-marketing surveillance study

BACKGROUND

CustomBone Service (CBS) is a patient-specific, biocompatible, and osteoconductive device made of porous hydroxyapatite, indicated for cranial reconstruction in adults and children. Adult literature data report a failure rate of about 8%. The aim of this Post-Marketing Surveillance study is to verify the hypothesis that CBS in children aged 7-13 years old shows a failure rate not superior to adults.

MATERIALS AND METHODS

Inclusion criteria were age at implantation ranging 7-13 years old, with at least 1 year elapsed from the date of surgery. The degree of satisfaction of surgeons and patients was assessed.

RESULTS

Data about 76 implants in 67 patients (M:F = 41:26) were obtained from 28 centers across 7 European countries. The mean age at surgery was 10.03 ± 1.72 years, with age stratification almost equally distributed. Fifty-nine subjects received one CBS, 7 subjects two and one subject received three CBS. Main etiologies were trauma (60.5%), malformation (11.8%), bone tumor (10.5%), and cerebral tumor (7.9%). Main indications to CBS were decompression (47.4%), autologous bone resorption (18.4%), tumor resection (11.8%), malformation (9.2%), comminuted fracture (5.3%), and other materials rejection (5.3%). Main implantation sites were fronto-parieto-temporal (26.3%), parietal (23.7%), frontal (11.8%), fronto-temporal (10.5%), and parieto-temporal (7.9%). CBS was chosen as first line of treatment in 63.1% of the cases. Mean follow-up was about 36 months. Eleven adverse events (14.5%) were reported in nine devices. Five CBS required explantation (three cases of infection, one fracture, and one mobilization). Failure rate was 6.58%, which is statistically not superior to the explantation rate recorded in adults (two-sided 95%, CI 2.2-14.7%). Satisfaction of surgeons and patients was of about 95%.

CONCLUSION

CBS is a safe and effective solution for cranial repair in pediatric patients. In particular, over the age of 7, CBS shows a rate of failure as low as in adults.

Long-Term Follow-Up Comparative Study of Hydroxyapatite and Autologous Cranioplasties: Complications, Cosmetic Results, Osseointegration

OBJECTIVE

A three-dimensional reconstruction technique using the CustomBone (CB) prosthesis allows custom-made cranioplasty (CP) possessing osseointegration properties owing to its porous hydroxyapatite (HA) composition. This reconstruction technique has replaced less expensive techniques such as subcutaneously preserved autologous bone (SP). Our primary objective was to evaluate complications between CB and SP CP techniques. A secondary objective was to assess cosmetic results and osseointegration of CPs.

METHODS

This single-center study comprised patients undergoing delayed CB or SP CP after craniectomy between 2007 and 2014. A prospective interview was conducted to collect all data, including 2-year follow-up clinical and radiologic data. Cosmetic results were assessed by a qualitative score, and osseointegration was assessed by measuring relative fusion at the CP margins.

RESULTS

Of 100 patients undergoing CB or SP CP between 2007 and 2014, 92 (CB, n = 44; SP, n = 48) participated in the prospective interview. No significant difference in complication rates was observed between the 2 groups. The main complication specific to the CB group was fracture of the prosthesis observed in 20.8% patients. A higher rate of good cosmetic results was observed in the CB group (92.5% vs. 74.3%, P = 0.031). In the CB group, 51% of patients demonstrated no signs of bone fusion of the CP.

CONCLUSIONS

Although the CB prosthesis is associated with cosmetic advantages, the porous hydroxyapatite composition makes it fragile in the short-term and long-term, and effective osseointegration remains uncertain.