Lateral access minimally invasive spine surgery in adult spinal deformity.

Background: Oblique lumbar interbody fusion (OLIF) and percutaneous posterior approach for screw fixation (PPS) is the latest minimal invasive treatment for spinal deformity in adult patients (ASD). This study aims to design and highlight key points for ASD correction. Materials and methods: We retrospectively analyzed 54 patients who had undergone OLIF with PPS for ASD from October 2019 to January 2022 (average 71.5 ± 6.2 years-old, male 4, female 50) with a mean follow-up period of 29.2 months. Clinical outcomes are expressed by values including the Oswestry disability index (ODI) and visual analogue scale (VAS) for back pain. The imagistic assessment was also performed preoperatively and at 12, and 24 months postoperatively. For OLIF51, CT- MRI fusion images were obtained before surgery. Results: Postoperative ODI and VAS were 30.5 ± 18.9% and 31.2 ± 6.9 mm, respectively. The average operating time and blood loss during the surgical exposure was 490.9 ± 85.4 min and 1195.2 ± 653.8 ml. Preoperative SVA, PI-LL, and PT were 96.5 ± 55.9 mm, 39.3 ± 22.1°, 34.5 ± 11.0°, respectively. Postoperatively, SVA and PT became normal (24.1 ± 39.0 mm, 17.1 ± 10.3°) and PI-LL was ideal (2.4 ± 12.6°). Postoperative ODI and VAS were 30.5 ± 18.9% and 31.2 ± 6.9 mm. For OLIF51, the results revealed gain in L5-S1 lordosis and intervertebral disc height 9.4° and 4.2 mm respectively. The complications consisted of PJK in 21 cases (38.9%), rod breakage in 5 cases (9.3%), deep or superficial wound infection in 2 cases (3.7%). Conclusion: Clinical and imagistic results of OLIF and PPS for ASD were excellent. The radiographic measurements revealed that OLIF51 created good L5-S1 lordosis and significant L5-S1 disc height. CT-MRI fusion images were very useful for evaluating vascular anatomy for OLIF51.