Osteointegration and Fusion After TLIF: Trabecular Titanium Cage with SVF-Hydrogel Compared with PEEK Cage

Degenerative lumbar spinal stenosis is a leading cause of disability, and lumbar interbody fusion (LIF) is a common surgical option. However, pseudarthrosis and suboptimal fusion remain important limitations. Porous titanium cages with biologically active hydrogels may enhance osteointegration compared with PEEK implants.

This single-centre prospective randomized trial included 50 patients with lumbar stenosis undergoing single-level TLIF. Patients were allocated 1:1 to Group I (trabecular Ti-6Al-4V cage with autologous bone and stromal-vascular fraction-based heparin-conjugated fibrin hydrogel) or Group II (PEEK cage with autologous bone only). Follow-up was 12 months. Primary endpoints were CT-based fusion at 12 months (Tan classification) and bone density within the cage region (Hounsfield units, HU). Secondary outcomes included pain (VAS), disability (ODI), implant subsidence/migration, operative parameters, and complications.

Baseline demographic and clinical characteristics and intraoperative blood loss were comparable between groups. Mean HU values were significantly higher in Group I at 3-4, 6 and 12 months (428.0±68.6 vs 388.8±46.6, p=0.0228; 527.5±81.8 vs 466.4±52.7, p=0.0031; 594.8±78.7 vs 521.0±75.0, p=0.0014). Complete fusion (Tan grade 1) at 12 months was achieved in 68% of Group I versus 32% of Group II patients (p=0.0227). Group I also showed greater VAS and ODI improvement at all postoperative time points. No intraoperative complications or hydrogel-related adverse events were observed.

A trabecular titanium cage combined with autologous bone and SVF-based hydrogel appears safe and more effective than a PEEK cage with autograft, providing superior radiological fusion and faster recovery at 12 months.