Clinical Experience with High-Viscosity Cements for Percutaneous Vertebral Body Augmentation: Occurrence, Degree, and Location of Cement Leakage Compared with Kyphoplasty

Vertebroplasty is known for its high leakage rate compared with kyphoplasty. In recent preclinical studies, high-viscosity cements were shown to significantly enhance the uniformity of cement filling and decrease the incidence of leakage in cancellous bonelike substrates compared with low-viscosity cements. In this study, the incidence and pattern of cement leakage by using a new high-viscosity cement (Confidence spinal cement system) was compared with that of standard kyphoplasty. Postoperative radiographs of patients treated with either kyphoplasty or Confidence were analyzed for cement leakage by using a stringent and thorough 4-point scale (none, minimal, moderate, or severe). When leakage was observed, the location of the cement leakage was also recorded and described as diskal, venous, paravertebral, or epidural. Sixty-two consecutive patients with 112 treated levels were included in this retrospective review. There were 46 kyphoplasty- versus 66 Confidence-treated levels, which ranged from T3 to L5. The average vertebral collapse reached 27.9 +/- 20.7% in the Confidence group versus 25.0 +/- 19.1% in the kyphoplasty group. There was no or mild leakage in 92% of Confidence and 91% of the kyphoplasty cases (mild, 39% Confidence versus 50% kyphoplasty). Severe leakage was only reported in 1 (2%) Confidence and 1 (2%) kyphoplasty case. In both cases, the severe leakage was found in the disk space. No significant leakage that required any surgical intervention was noticed. This finding confirms prior observations that highly viscous cements may increase the safety of vertebral augmentation techniques compared with less viscous cements. The high-viscosity Confidence cement results in a leakage rate comparable with that of kyphoplasty.