Long-term complications of minimally-open anterolateral interbody fusion for L5-S1

Background: Multiple surgical techniques and approaches exist to obtain lumbar interbody fusion. Anterolateral (oblique) is a relatively recent technique. Controversy exists for its use at the L5-S1 level. We performed this study in order to show the safety and efficacy of this technique. The aim of this study was to report the long-term complications and fusion rates of minimally-open (mini-open) anterolateral interbody fusion at the L5-S1 level.

Methods: We retrospectively analyzed all patients who underwent mini-open anterolateral interbody fusion for L5-S1 level in our department. The data collected were the following: age, sex, surgical indication, acute (less than four weeks) and long-term complications (>3 months), fusion at six months and length of follow-up.

Results: Seventeen patients (8M/9F) underwent mini-open anterolateral interbody fusion at L5-S1. The mean age was 64.5 years. The surgical indication was scoliosis in 10 cases, flat back in 4 cases, and spondylolisthesis in 3 cases. All patients underwent a complementary posterior procedure that included fixation. Mean blood loss was 252.9mL for the anterior procedure. Eight acute and minor complications occurred (anemia, delirium, and psoas paresis). Two acute complications required surgical intervention (cage displacement and hematoma). Long-term complications were observed in 2 cases and included proximal junction kyphosis and non-union. The fusion rate was evaluated at 88%. The mean follow-up period was 28.3 months.

Conclusions: Mini-open anterolateral interbody fusion at the L5-S1 level is safe and results in fusion at the same rate as anterior interbody fusion. Most acute complications are minor and resolve spontaneously.