1. 2019;22;E91-E96Age, Gender, Level and Side Differences in the Anatomical Distinctions of Unilateral Percutaneous Kyphoplasty through the Transverse Process-Pedicle Approach
   Observational Study
   Hongwei Wang, PhD, Pan Hu, MD, Deluo Wu, MD, Ning Zhang, MD, Jun Wu, MD, and Liangbi Xiang, PhD.

BACKGROUND: Unilateral and bilateral percutaneous kyphoplasty (PKP) have been widely adopted to treat osteoporotic vertebral compression fractures (OVCFs). Unilateral PKP has a shorter operation time and less radiation exposure time compared with bilateral PKP, but the anatomical distinctions of unilateral PKP are not identical in all cases.

OBJECTIVE: The aim of this study was to examine the significance of age, gender, level, and side in relation to the anatomical distinctions of unilateral PKP for lumbar OVCFs through the transverse process-pedicle approach (TPPA).

STUDY DESIGN: This was a retrospective study of 200 patients.

SETTING: The research took place at General Hospital of Shenyang Military Area Command of Chinese PLA.

METHODS: Researchers examined 1000 lumbar spines (L1-L5) of 200 patients and simulated PKP on the 3D-CT scans through unilateral TPPA. The distance between the entry point and the midline of the vertebral body (DEM), the puncture inclination angle (PIA), the safe range of the inner inclination angles (SRA), and the success rate (SR) of puncture were measured and compared.

RESULTS: There were significant differences (P < 0.05) in the mean DEM between men and women, and between the left and right sides. The DEM was significantly larger in men than women and in right than left. The DEM from L1 to L5 was significantly increased (P < 0.05), from 22.4 ± 2.0 mm to 34.1 ± 4.3 mm. The right maximum PIA was significantly larger than the left. The maximum puncture angle and SRA in men was larger than that in women except for L5. The SRA from L1 to L5 was significantly increased (P < 0.05), from 20.1 ± 6.0 mm to 44.2 ± 8.8 mm. The SR from L1 to L5 was significantly increased (P < 0.05), from 88.3% to 100%. The SR in men was significantly higher than that in women for L1 and L2.

LIMITATIONS: Sample size was relatively small.

CONCLUSIONS: The DEM was 22.4 mm to 34.1 mm according to different levels. There were significant gender, side, and age differences in the DEM and PIA. The values of DEM, PIA, SRA and SR were significantly increased from L1 to L5.

KEY WORDS: Lumbar, osteoporotic vertebral compression fracture, unilateral, percutaneous kyphoplasty, transverse process.