Anterior lumbar interbody fusion: lumbar approach, complications, and their prevention

Stand-alone ALIF versus TLIF in patients with low back pain - A propensity-matched cohort study with two-year follow-up

Introduction

Instrumented lumbar fusion by either the anterior or transforaminal approach has different advantages and disadvantages. Few studies have compared PatientReported Outcomes Measures (PROMs) between stand-alone anterior lumbar interbody fusion (SA-ALIF) and transforaminal lumbar interbody fusion (TLIF).

Research question

This is a register-based dual-center study on patients with severe disc degeneration (DD) and low back pain (LBP) undergoing single-level SA-ALIF or TLIF. Comparing PROMs, including disability, quality of life, back- and leg-pain and patient satisfaction two years after SA-ALIF or TLIF, respectively.

Material and methods

Data were collected preoperatively and at one and two-year follow-up. The primary outcome was Oswestry Disability Index (ODI). The secondary outcomes were patient satisfaction, walking ability, visual analog scale (VAS) scores for back and leg pain, and quality of life (QoL) measured by the European Quality of Life-5 Dimensions (EQ-5D) index score. To reduce baseline differences between groups, propensity-score matching was employed in a 1:1 fashion.

Results

92 patients were matched, 46 S A-ALIF and 46 TLIF. They were comparable preoperatively, with no significant difference in demographic data or PROMs (P > 0.10). Both groups obtained statistically significant improvement in the ODI, QoL and VAS-score (P < 0.01), but no significant difference was observed (P = 0.14). No statistically significant differences in EQ-5D index scores (P = 0.25), VAS score for leg pain (P = 0.88) and back pain (P = 0.37) at two years follow-up.

Conclusion

Significant improvements in ODI, VAS-scores for back and leg pain, and EQ-5D index score were registered after two-year follow-up with both SA-ALIF and TLIF. No significant differences in improvement.

ALIF WITH AUTO-LOCKING CAGE WITHOUT SUPPLEMENTATION - TOMOGRAPHIC ANALYSIS OF INTERBODY BONE FUSION

ABSTRACT Objective: The objective of this work is to study the fusion rate and complications of the mini-ALIF with an auto-locking device at the L5-S1 level. Methods: Retrospective and radiological study. The inclusion criteria were mini-ALIF in L5-S1 with auto-locking cage, DDD and/or low grade spondylolisthesis. The exclusion criteria were posterior/anterior supplementation; lack of 12-month follow-up images, and previous surgery at L5-S1 level. The primary endpoint was fusion assessed in CT images and/or lateral lumbar flexion/extension radiographs. The secondary endpoint was the revision surgery due to device movement/migration or pseudoarthrosis. Lumbar TCs and radiographs were analyzed during 12 months of follow-up. Fusion was defined according to Bridwell/Lenke classification. Results: Sixty-one cases were included in this study. Complete or ongoing fusion was found in 57 cases (93%). Forty-two of the 61 levels (65%) were completely fused after 12 months. Fifteen levels (28%) had evident bone growth, two levels (3%) showed lysis lines around the implant, and two levels (3%) presented lysis lines and depression. Reoperation for pedicular screw supplementation was necessary in two cases (3%), one with vertebral sliding progression (12 months), and one with symptomatic micro-movement (six months). No implant has undergone migration or expulsion of the disc space. Conclusions: Mini-ALIF in L5-S1 level using an auto-blocking interbody implant construction in cases of low segmental instability results in good interbody fusion index and low failure rate, even without the need for further supplementation, but should not be applied indiscriminately. Evidence Level: IV. Type of study: Case series.

Clinical outcome of stand-alone ALIF compared to posterior instrumentation for degenerative disc disease: A pilot study and a literature review

The objective of the article was to: a) present results from a case cohort pilot study comparing stand-alone ALIF and TLIF and, b) review the literature on studies comparing the clinical outcome of stand-alone ALIF with posterior instrumentation including TLIF or PLIF, in patients with disabling low back pain resulting from degenerative disc disease. ALIF surgery has previously been linked with certain high risk complications and unfavorable long term fusion results. Newer studies suggest that stand-alone ALIF can possibly be advantageous compared to other types of posterior instrumented interbody fusion for a selected group of DDD patients. The methods and material consisted of a cohort pilot study of patients, with DDD treated with stand-alone ALIF or TLIF followed by a literature review conducted through a comprehensive PubMed database search of the English literature. Studies comparing stand-alone ALIF with posterior instrumented interbody fusion were selected and reviewed. Results from the pilot study, n = 21, showed a reduced perioperative blood loss, shorter operative time and a trend towards better pain reduction and decreased use of opioid analgesics in patients undergoing stand-alone ALIF compared to posterior instrumented fusion with TLIF. The literature review included three studies, n = 630. All three studies were retrospective cohort studies. The average patient follow-up was 2-years but with heterogeneous selected outcomes. Two of three articles documented significant advantages when using stand-alone ALIF on outcomes such as ODI, VAS, surgical time, blood loss and patient satisfaction. No study found stand-alone ALIF inferior in chosen outcomes including fusion. In conclusion the pilot study and the literature review, finds similar clinical outcomes and fusion rates after stand-alone ALIF and posterior interbody fusion. Stand-alone ALIF was associated with a shorter duration of surgery, less perioperative blood loss and a faster improvement post-operatively. Therefore stand-alone ALIF is a viable and important surgical option, which could be considered first choice as surgical treatment.