We evaluated the clinical outcomes and limitations of anterior and posterior combined surgery with a mini-open corpectomy applying an expandable cage (Xcore®) and percutaneous pedicle screw (PPS) fixation using single-position surgery in the lateral decubitus position in patients aged > 75 years with thoracolumbar vertebral collapse. The cases of 30 consecutive patients who underwent this procedure and had ≥ 1-year follow-up were retrospectively analyzed. The mean operative time was 78.8 min and the estimated blood loss was 115.7 ml per level. The complications included adjacent junctional failure (n=9, 30%), deep venous thrombosis (n=3, 10%), delirium (n=3, 10%), pleural injury (n=2, 6%), screw backout (n=1, 3%) kidney injury (n=1, 3%), chylothorax (n=1, 3%), and wound dehiscence (n=1, 3%). Seven cases (23.3%) required reoperation. Local kyphosis showed significant improvement (p<0.05) that was maintained at the final follow-up. The Japanese Orthopaedic Association Back Pain Evaluation Questionnaire and a visual analogue scale indicated significant improvement in all categories at the final follow-up (p<0.05). The use of mini-open corpectomy and posterior fixation with SPAPS can thus provide reliable radiological correction and good postoperative clinical outcomes even in patients aged > 75 years. However, a limitation of this procedure is the rate of reoperation (23.3%) for osteoporosis-related adjacent segment fracture and screw backout.