The connection between the basivertebral foramen and the intravertebral cleft could be a related factor of cement leakage after percutaneous kyphoplasty

Abstract

Objective To assess incidence rate of different types of cement leakage in percutaneous kyphoplasty (PKP) with or without intravertebral clefts and to determine whether basivertebral foramen could be connected with intravertebral cleft.Methods 270 vertebrae in 224 consecutive patients who underwent percutaneous kyphoplasty for treatment of osteoporotic vertebral compression fractures were classified into two groups on preoperative radiographs,computed tomography scans,and/or magnetic resonance images of the treated levels:Cleft group with an intravertebral cleft in vertebral body and trabecular group without intravertebral clefts.On direct postoperative images,the patterns of cement leakage were classified as 5 types:through a cortical defect into paraspinal soft tissues (type A),through the basivertebral foramen (type B),via the needle channel (type C),through a cortical defect into the disc space (type D),via the paravertebral vein (type E).The incidence of different types of cement leakage between two groups was analyzed.Results In 72 of 270 vertebrae,an intravertebral cleft was confirmed on preoperative images.Leaks through basivertebral foramen as type B (42,15.5％) and through cortical defects into the disc space as type D leaks (21,7.8％) were more common than other types.The incidence of type B leakage in the cleft group (23.6％) was higher than the incidence in the trabecular group (12.6％),which made a statistical significance (P=0.028).There was no statistical difference between the trabecular pattern and the cleft pattern on other types of leaks.Conclusion Type B leaks were more common in vertebrae with the presence of an intravertebral cleft,which support the presence of the connection between an intravertebral cleft and the basivertebral foramen.Thus,care must be taken when PKP was performed in these patients to avoid cement leakage into spinal canal through basivertebral foramen directly. Key words: Kyphoplasty; Osteoporotic fractures; Fractures, compression