Arthrodesis Rate and Patient Reported Outcomes After Anterior Lumbar Interbody Fusion Utilizing a Plasma-Sprayed Titanium Coated PEEK Interbody Implant: A Retrospective, Observational Analysis.

BACKGROUND: Anterior lumbar interbody fusion (ALIF) is utilized in symptomatic spinal disc destabilization due to degenerative lumbar disc disease, isthmic and degenerative spondylolisthesis, internal disc disruption, or pseudarthrosis after non-operative treatments fail. The addition of a plasma-sprayed titanium coating (PTC) to polyether ether ketone spacers (PEEK) may reduce the rate of implant subsidence or non-union secondary to poor osseous-integration of non-coated PEEK or metal interbody systems.

METHODS: A retrospective, non-randomized, single-center chart review, evaluated the post-surgical follow-up data of patients receiving a PTC PEEK implant during single or multi-level ALIF procedures to determine the clinical efficacy and rate of arthrodesis after utilization of a coated spacer. Standard roentgenographs or computed tomography were used to identify successful arthrodesis following the ALIF procedure and longitudinal clinical improvements were determined by scores on the Visual Analog Scale (VAS) for low back and leg pain.

RESULTS: Forty-four subjects (48% male, mean=53 years) were included in this chart review. Follow-up radiology demonstrated radiographic union with bridging bone formation across the interbody space for 42/44 (96%) individuals with solid arthrodesis occurring at an average of 7.3 ± 2.3 months. Subjects demonstrated significant improvement in VAS low back pain (4.5 ± 2.4 point improvement, p=0.0001) and VAS leg pain (4.1 ± 3.3 point improvement, p=0.0001). While there was a significant reduction in the improvement of VAS low back pain of Worker's Compensation claimants as compared to other patients (3.9 ± 2.4 vs. 5.3 ± 2.1), there was no difference in VAS low back pain or leg pain when the data was stratified by gender, age, tobacco use, comorbidities, prior surgery, fusion construct length, use of supplemental posterior instrumentation, BMI, or diagnosis.

CONCLUSIONS: This study provides support that the addition of a PTC coating to a zero-profile PEEK lumbar interbody spacer facilitates rapid and stable fixation at the bone-implant interface. This facilitated osteogenesis is associated with significantly improved pain outcomes, low implant subsidence and a high definitive rate of arthrodesis. Future studies should include a prospective, randomized, controlled, multi-center approach to directly compare arthrodesis rates and clinical outcomes longitudinally between standard PEEK and biomaterial-coated PEEK interbody spacer systems.