Less is more: complication rates and outcome measures of intradiscal osteotomy versus pedicle subtraction osteotomy in adult spinal deformity

J Neurosurg Spine 43:313–323, 2025

In adults with spinal deformity, intradiscal osteotomy (IDO) is as effective as pedicle subtraction osteotomy (PSO) for lordosis restoration and sagittal balance, with similar complication rates but significantly less blood loss, shorter operative time, and less postoperative back pain at 3 months.

• Intradiscal osteotomy (IDO) and pedicle subtraction osteotomy (PSO) are both used to correct adult spinal deformity, aiming to restore lumbar lordosis and sagittal balance.

• IDO and PSO showed similar fusion rates and complication profiles, with no statistically significant difference in rates of proximal junctional kyphosis, hardware failure, DVT, wound infection, or pseudarthrosis.

• IDO resulted in significantly less estimated blood loss (800 ml vs. 1400 ml) and shorter operative time (7 vs. 8.5 hours) compared to PSO.

• IDO patients reported less back pain at 3 months post-op (VAS 1 vs. 3, p=0.01) than PSO patients.

• Both techniques effectively restored lumbar lordosis, but IDO achieved better postoperative sagittal vertical axis (SVA) correction (5 cm vs. 7 cm, p=0.01).

• Higher BMI was a significant risk factor for postoperative complications in both groups.

• IDO is less technically complex, preserves vertebral body integrity, and is more familiar to spine surgeons than PSO.

• IDO can be considered an effective and potentially safer alternative to PSO for selected adult spinal deformity patients.

The Mini-Open Pedicle Subtraction Osteotomy for Flat-Back Syndrome and Kyphosis Correction

Operative Neurosurgery 12:309–316, 2016

The pedicle subtraction osteotomy (PSO) has been a mainstay treatment for flat-back syndrome. The morbidity of open deformity correction can be high, and minimally invasive applications may reduce such morbidity.

OBJECTIVE: To describe an operative technique of the mini-open PSO.

METHODS: Two patients underwent percutaneous fixation above and below the PSO, and the PSO was performed in a mini-open fashion. The correction was obtained by cantilever.

RESULTS: The patient who underwent the L3 PSO had a prior fusion from T11 to L4 for scoliosis 35 years ago. On presentation at 62 years of age, he had a pelvic incidence of 54, lumbar lordosis of 23, sagittal vertical axis of 114 cm, and pelvic tilt of 25. He underwent an anterior lumbar interbody fusion at L5-S1 followed by a min-open L3 PSO. He had a postoperative lumbar lordosis of 64 (correction of 41), and his sagittal vertical axis went to 13 cm. His Oswestry Disability Index and visual analog scale scores decreased after surgery. The second patient was 64 years of age and underwent an L1 PSO. He had 43 of kyphosis from T10 to L2. He had a preoperative pelvic incidence of 63, lumbar lordosis of 35, pelvic tilt of 24, and sagittal vertical axis of 3 cm. His postoperative kyphosis improved from 43 to 32.

CONCLUSION: The mini-open PSO can achieve significant lordosis, although it is heavily reliant on anterior arthrodesis. Larger studies are needed to compare this approach with an open PSO.