Purpose:

The objective of this study was to assess the morbidity of Anterior Lumbar Interbody Fusion (ALIF) using an intervertebral tantalum implant. Tantulum is an extremely porous metallic material which possesses properties of osseointegration, osteoinduction and osteoconduction while offering superior primary stability, compared to other materials more commonly used (polyether ether ketone or PEEK, titanium). Perioperative morbidity, short-term functional outcomes (2 years) and radiographic impaction of implants were also analysed.

Methods:

This retrospective monocentric study involved 94 patients operated on between 2014 and 2017 for degenerative disc disease (75%), degenerative spondylolisthesis (3%) or isthmic lytic spondylolisthesis (22%). Sixty-five patients (69%) had isolated (“stand-alone”) ALIF procedures, 24 (26%) with associated anterior osteosynthesis and 5 (5%) with associated posterior osteosynthesis. A Kaplan-Meier survival curve was established with surgical revision listed as the main criterion for failure. Perioperative complications were identified. The clinical evaluation at the last follow-up used a Visual Analogue Scale for radicular pain (VAS-R), for lumbar pain (VAS-L) and the Oswestry Disability Index (ODI) score. The impactions, assessed on x-rays, were divided into 2 groups according to severity in order to establish risk factors (RF).

Results:

The primary objective showed a 2-year survival rate of 94% (95% CI [0.88; 0.99]). Two patients had early surgical revision for impaction and 4 patients had late surgical revision for pseudarthrosis. The rate of perioperative complications was 8.5%, mostly due to vascular causes. At the average follow-up of 33 months (24-59), the clinical results were significantly improved and the impaction rate was 36% in the immediate postoperative period (IPO) and 47% at one year.

Conclusion:

ALIF using an intervertebral tantalum implant is a reliable, reproducible and low morbidity technique. However, it is accompanied by a significant rate of immediate and secondary impaction but without any resounding influence on short-term clinical outcomes.

Level of evidence:

IV.