Lateral lumbar interbody fusion for sagittal balance correction and spinal deformity

• The direct or extreme lateral lumbar interbody fusion (XLIF) approach has been recently introduced, and a systematic review was conducted to assess its safety, clinical and radiological outcomes.
• Minimally invasive XLIF procedures appear to be a safe alternative for restoration of sagittal balance and treatment of scoliosis, with improved functional outcomes and restored coronal Cobb angles.
• There are limited corrections in lumbar lordosis and coronal alignment.
• Future comparative studies are warranted to assess long-term benefits and risks of XLIF compared to anterior and posterior procedures.

We conducted a systematic review to assess the safety and clinical and radiological outcomes of the recently introduced, direct or extreme lateral lumbar interbody fusion (XLIF) approach for degenerative spinal deformity disorders. Open fusion and instrumentation has traditionally been the mainstay treatment. However, in recent years, there has been an increasing emphasis on minimally invasive fusion and instrumentation techniques, with the aim of minimizing surgical trauma and blood loss and reducing hospitalization. From six electronic databases, 21 eligible studies were included for review. The pooled weighted average mean of preoperative visual analogue scale (VAS) pain scores was 6.8, compared to a postoperative VAS score of 2.9 (p < 0.0001). The weighted average preoperative and postoperative coronal segmental Cobb angles were 3.6 and 1.1°, respectively. The weighted average preoperative and postoperative coronal regional Cobb angles were 19.1 and 10.0°, respectively. Regional lumbar lordosis also significantly improved from 35.8 to 43.3°. Sagittal alignment was comparable pre- and postoperatively (34 mm versus 35.1 mm). The weighted average operative duration was 125.6 minutes, whilst the mean estimated blood loss was 155 mL. The weighted average hospitalization length was 3.6 days. Whilst the available data is limited, minimally invasive XLIF procedures appear to be a promising alternative for the treatment of scoliosis, with improved functional VAS and Oswestry disability index outcomes and restored coronal deformity. Future comparative studies are warranted to assess the long term benefits and risks of XLIF compared to anterior and posterior procedures.