CIRCULATORY EFFECTS OF BALLOON KYPHOPLASTY, AND EFFECTIVENESS OF EGG SHELL CEMENTOPLASTY TO PREVENT CEMENT LEAKAGE.

Abstract

The circulatory effects of multilevel balloon kyphoplasty (BK) are not adequately addressed, neither the effectiveness of egg shell cementoplasty in preventing anticipated cement leakage in difficult cases. The purpose of this study was to evaluate

1. the effect of multilevel BK to blood pressure and arterial blood gasses;

2. the incidence of methylmethacrylate cement leakage using routine postoperative computer tomography scan and

3. the effectiveness of egg shell cementoplasty to prevent cement leaks.

Materials and methods: This is a prospective study of 89 patients (215 vertebral bodies-VBs) with osteoporotic compressive fractures (OCF), and 27 with osteolytic tumors (OT) (88 VBs). The mean age was 67.6 years. 27 patients with OCF were treated at one level, 26 at two, 21 at three, 7 at four, 6 at five, and 2 at six levels at the same sitting. Three patients with OT were treated at one level, 6 at two, 9 at three, 3 at four, 4 at five, and 2 at seven. Egg shell balloon cementoplasty to prevent cement leakage was performed in 10 patients with severe endplate fracture or vertebral wall lytic destruction. Arterial blood pressure and oxygen saturation were monitored during surgery. Arterial blood gases were measured before and 3 min after cement injection. Cement leakage was assessed by the postoperative x rays and computer tomography scans.

Results: A drop in blood pressure of more than 25mmHg during cement injection was observed in 6 patients, and was not associated with the number of VB treated. Blood pressure was dropped more than 40mm in 2 patients and the procedure was aborted after completing 1 level in the first and 2 levels in the second. Drop in arterial O2 saturation was noted in 4 patients. One patient treated for 5 levels developed fever and tachepnoea for 24 hours after surgery. Arterial O2 and chest x-rays were normal. Cement leakage was found in 9.7% (21/215) of VBs treated for OCF. Its incidence per location was: epidural, 0.9% (2 VBs); intraforaminal, 0.5% (1 VB); intradiscal, 3.2% (7 VBs); and through anterior or lateral walls, 5.1% (11 VBs). In the OT group cement leakage was found in 10.2% (9/88) of the treated VBs. Its location included 8 (9%) through the anterior or lateral walls and one (1.1%) intradiscal. Cement leakage had no clinical consequences. No cement leakage was observed in cases treated with egg shell balloon cementoplasty.

Conclusions: BK is a safe procedure when applied for multiple levels in the same sitting, and its rare circulatory effects are not related to the number of levels treated. The incidence of cement leakage in this study was 10%, which is far less than that reported with vertebroplasty using routine postoperative CT scan. Egg shell balloon cementoplasty can effectively minimize cement leakage in cases with fractured endplate or lytic destruction of VB walls.