The Efficacy of Trabecular Titanium Cages to Induce Reparative Bone Activity after Lumbar Arthrodesis Studied through the 18f-Naf PET/CT Scan: Observational Clinical In-Vivo Study

Fabio Cofano; Daniele Armocida; Livia Ruffini; Maura Scarlattei; Giorgio Baldari; Giuseppe Di Perna; Giulia Pilloni; Francesco Zenga; Elena Ballante; Diego Garbossa; Fulvio Tartara

doi:10.3390/diagnostics12102296

The Efficacy of Trabecular Titanium Cages to Induce Reparative Bone Activity after Lumbar Arthrodesis Studied through the 18f-Naf PET/CT Scan: Observational Clinical In-Vivo Study

Diagnostics (Basel). 2022 Sep 23;12(10):2296. doi: 10.3390/diagnostics12102296.

Authors

Fabio Cofano^{1

2}, Daniele Armocida³, Livia Ruffini⁴, Maura Scarlattei⁴, Giorgio Baldari⁴, Giuseppe Di Perna¹, Giulia Pilloni⁵, Francesco Zenga¹, Elena Ballante^{6

7}, Diego Garbossa¹, Fulvio Tartara⁸

Affiliations

¹ Neurosurgery Unit, Department of Neuroscience, University of Turin, 10124 Turin, Italy.
² Spine Surgery Unit, Humanitas Gradenigo, 10153 Turin, Italy.
³ Neurosurgery Unit, Department of Human Neuroscience, Sapienza Università of Rome, 00185 Rome, Italy.
⁴ Nuclear Medicine Unit, University Hospital of Parma, 43100 Parma, Italy.
⁵ Neurosurgery Unit ASST Fatebenefratelli Sacco, 20121 Milan, Italy.
⁶ BioData Science Center, IRCCS Mondino Foundation, 27100 Pavia, Italy.
⁷ Department of Mathematics, University of Pavia, 27100 Pavia, Italy.
⁸ Neurosurgery Unit, ICCS Città Studi, 20131 Milan, Italy.

Abstract

Background: Titanium trabecular cages (TTCs) are emerging implants designed to achieve immediate and long-term spinal fixation with early osseointegration. However, a clear radiological and clinical demonstration of their efficacy has not yet been obtained. The purpose of this study was to evaluate the reactive bone activity of adjacent plates after insertion of custom-made titanium trabecular cages for the lumbar interbody with positron emission tomography (PET)/computed tomography (CT) 18F sodium fluoride (18F-NaF). Methods: This was an observational clinical study that included patients who underwent surgery for degenerative disease with lumbar interbody fusion performed with custom-made TTCs. Data related to the metabolic-reparative reaction following the surgery and its relationship with clinical follow-up from PET/CT performed at different weeks were evaluated. PET/CTs provided reliable data, such as areas showing abnormally high increases in uptake using a volumetric region of interest (VOI) comprising the upper (UP) and lower (DOWN) limits of the cage. Results: A total of 15 patients was selected for PET examination. Timing of PET/CTs ranged from one week to a maximum of 100 weeks after surgery. The analysis showed a negative correlation between the variables SUVmaxDOWN/time (r = -0.48, p = 0.04), ratio-DOWN/time (r = -0.53, p = 0.02), and ratio-MEAN/time (r = -0.5, p = 0.03). Shapiro-Wilk normality tests showed significant results for the variables ratio-DOWN (p = 0.002), ratio-UP (0.013), and ratio-MEAN (0.002). Conclusions: 18F-NaF PET/CT has proven to be a reliable tool for investigating the metabolic-reparative reaction following implantation of TTCs, demonstrating radiologically how this type of cage can induce reparative osteoblastic activity at the level of the vertebral endplate surface. This study further confirms how electron-beam melting (EBM)-molded titanium trabecular cages represent a promising material for reducing hardware complication rates and promoting fusion.

Keywords: lumbar arthrodesis; titanium trabecular cages.

Grants and funding

This research received no external funding.