The effect of void creation prior to vertebroplasty on intravertebral pressure and cement distribution in cadaveric spines with simulated metastases

Abstract

BackgroundFor osteoporosis or spinal metastases, percutaneous vertebroplasty is effective in pain relief and improvement of mobility. However, the complication rate (cement extravasation and fat embolisms) is relatively higher in the treatment of spinal metastases. The presence of tumor tissue plays a significant role in intravertebral pressure and cement distribution and thereby affects the occurrence of complications. We investigated the effect of void creation prior to vertebroplasty on intravertebral pressure and cement distribution in spinal metastases.MethodsEighteen vertebrae (T8–L4) from five cadaveric spines were randomly allocated for two groups (group with and without void) of nine vertebrae each. Defect was created by removing a central core of cancellous bone in the vertebral body and then filling it with 30% or 100% fresh muscle paste by volume to simulate void creation or no void creation, respectively. Then, 20% bone cement by volume of the vertebral body was injected into each specimen through a unipedicular approach at a rate of 3 mL/min. The gender of the donor, vertebral body size, bone density, cement volume, and intravertebral pressure were recorded. Then, computed tomography scans and cross sections were taken to evaluate the cement distribution in vertebral bodies.ResultsNo significant difference was found between the two groups in terms of the gender of the donor, vertebral body size, bone density, or bone cement volume. The average maximum intravertebral pressure in the group with void creation was significantly lower than that in the group without void creation (1.20 versus 5.09 kPa, P = 0.001). Especially during the filling of void, the difference was more pronounced. Void creation prior to vertebroplasty allowed the bone cement to infiltrate into the lytic defect.ConclusionsIn vertebroplasty for spinal metastases, void creation produced lower intravertebral pressure and facilitated cement filling. To reduce the occurrence of complication, it may be an alternative to eliminate the tumor tissue to create a void prior to cement injection.

Effect of unilateral pulsed jet lavage prior to vertebroplasty on the intravertebral pressure and cement distribution

“…Yang et al [ 16 ] also reported the effect of pulsed lavage to remove the bone marrow, and similar positive outcomes were achieved. With less fat and marrow, the space in the trabeculae was expanded and would accommodate more bone cement [ 17 – 19 ]. Hence, less pressure would be transmitted and recorded from the contralateral side of the vertebral body.…”

Should kyphoplasty curettes be used in nonosteoporotic patients? A cautionary tale

“…It has already been demonstrated by several different studies that one of the reasons why kyphoplasty seems to be associated with lower rates of cement extravasation to endplates, epidural vessels and venous affluents of the inferior vena cava is the fact that the cement injection occurs at lower pressures once a cavity is created by the inflation of the balloon. In fact, it has been estimated that the injection pressure is reduced by more than threefold by the creation of a cavity in the vertebral body before cement injection (average maximum intravertebral pressure in the group with void creation versus the one without void creation of 1.20 vs 5.09 kPa, P = .001) …”

“…In fact, it has been estimated that the injection pressure is reduced by more than threefold by the creation of a cavity in the vertebral body before cement injection (average maximum intravertebral pressure in the group with void creation versus the one without void creation of 1.20 vs 5.09 kPa, P = .001). 14 Despite some arguments to the opposite, 15 most spine surgeons would still consider a breach in the posterior wall of the vertebral body, especially if considering a pathological fracture with an associated tumoral lesion, at least a relative contraindication to kyphoplasty due to the fear of cement leakage toward the spinal canal as well as further posterior displacement of tumoral tissue and/or cortical bone with risk of new onset of neurological deficits. 16 The use of curettes during kyphoplasty (a procedure to which we refer as cavitational kyphoplasty) 17 has emerged in the past few years as an interesting alternative for low-pressure cement injection while mitigating the possible associated risks of balloon inflation.Furthermore, there has been a growing amount of evidence suggesting that unilateral cement augmentation may provide similar benefits to a bilateral approach in terms of clinical outcomes, with lower operative times and radiation exposure.…”

Effect of unilateral pulsed jet lavage prior to vertebroplasty on the intravertebral pressure and cement distribution

“…Yang et al [16] also reported the effect of pulsed lavage to remove the bone marrow, and similar positive outcomes were achieved. With less fat and marrow, the space in the trabeculae was expanded and would accommodate more bone cement [17][18][19] .Hence, less pressure would be transmitted and recorded from the contralateral side of the vertebral body. Less bone leakage could also be achieved, and this finding was reported in previous bilateral lavage studies [6,7] .…”