Ponte osteotomy combined with bone bridge dissection and intervertebral bone grafting for the treatment of rigid degenerative scoliosis / 中华骨科杂志

ABSTRACT

Objective:To investigate the effect of Ponte osteotomy combined with bony bridge dissection and intervertebral bone grafting in the treatment of rigid degenerative scoliosis.Methods:From March 2017 to October 2021, this method was used to treat 21 cases of rigid degenerative scoliosis, including 7 males and 14 females, aged 59-76 years, with an average age of 67.6 years. All patients had intractable low back pain and limited standing and walking, while 15 patients had radiation pain in lower limbs. The preoperative standing X-ray film showed that the average Cobb angle of lumbar scoliosis was 51.3°±24.1°, the average lumbar lordosis was 5.4°±13.6°. The coronal balance distance (CBD) was 4.3±2.0 cm (range, 0.5-6.2 cm), and the sagittal vertical axis (SVA) was 5.9±3.1 cm (range, 1.5-6.8 cm). The bending images showed huge osteophyte with bone bridge formation in the vertebral body of the apex region, with poor mobility. Ponte osteotomy was performed according to the degeneration of the deformity. The bone bridge at apex area was cut off, and the intervertebral spaces at apex area and slipped or subluxated levels were release and grafted with granular autogenous decompression bone. During follow-up, the efficacy and deformity improvement were evaluated with visual analogue scale (VAS), Oswestry disability index (ODI) and standing X-ray films.Results:All patients successfully completed the operation. The operation time was 190-330 min, with an average of 250±68 min. The intraoperative bleeding was 700-1600 ml, with an average of 970±260ml. The patients were followed up for 12-36 months, with an average of 20.6±7.2 months. No internal fixation failure, fracture or revision occurred. At the last follow-up, the VAS of low back pain decreased from preoperative 6.1±2.2 to 2.1±1.8 ( t=6.45, P<0.001), and the leg pain decreased from 5.5±3.4 to 1.2±1.0 ( t=5.56, P<0.001).ODI decreased from 52.2%±22.2% to 16.4%±10.6% ( t=6.67, P<0.001). The Cobb angle of lumbar scoliosis was 19.3°±10.5°, with an average correction rate of 62.4%; lumbar lordosis was 34.4°±15.6 °, with average correction of 30°. CBD was 1.9±1.1 cm, with an average correction of 2.4 cm ( t=4.42, P<0.001); and SVA was 1.6±2.1 cm, with an average correction of 4.3 cm ( t=4.90, P<0.001). Conclusion:Ponte osteotomy combined with bone bridge dissection and intervertebral bone grafting is an effective method to treat rigid degenerative scoliosis, which can improve spinal sequence, CBD and SVA, avoid vertebral osteotomy and reduce fusion segments.