To assess the viability and effectiveness of mono-segmental percutaneous screw fixation in the treatment of unstable type B thoracolumbar fracture due to ankylosing spondylitis.

We report here all 40 patients treated by mono-segmental screw fixation in this indication, between January 2018 and January 2022, with follow-up at 3 and 9 months. Study variables comprised operating time, length of stay, fusion, stabilization quality, and peri-operative morbidity and mortality.

One patient showed early displacement of rods caused by technical error. None of the others showed secondary displacement of rods or screws. Mean age was 73 years (range 18–93), mean hospital stay 4.8 days (range 2–15), mean operative time 52minutes (range 26–95minutes) and mean estimated blood loss 40ml. There were 2 deaths caused by intensive care unit complications. All patients except those in intensive care were verticalized within 24hours after surgery. Parker score was unchanged for each patient before and after surgery and during follow-up.

Mono-segmental percutaneous screw fixation in the treatment of unstable type B thoracolumbar fracture due to ankylosing spondylitis was safe and effective. This study showed that this surgery reduced length of hospital stay, operative time, blood loss and complications compared to open or extended percutaneous surgery, and allowed fast rehabilitation in this vulnerable population.