Vertebral Body Stent (VBS)
Paul F Heini, Cornelius Wimmer, Thomas Pfandlsteiner, Rick Bransford
The vertebral body stent (VBS) system is an efficient method to treat painful, traumatic, and osteoporotic compression fractures, as well as osteolytic lesions. It addresses the procedural drawbacks of common and established treatment options like vertebro- and kyphoplasty which can result in either incomplete fracture reposition or in intraoperative loss of the restored vertebral body height [1].
The VBS is an expandable metal scaffolding (ie, a stent) which can be inflated from inside a vertebral body. Stent technology has been known for two decades to treat vascular diseases [2]. In 2002 Sebastian Fürderer first published the idea of implanting two balloon-expandable stents into fractured vertebral bodies [3], which has also been biomechanically assessed in comparison to simple balloon kyphoplasty [4]. The technology has been available since 2008 and has been applied in more than 4,000 levels.
VBS advantages
The surgical technique of VBS involves a unique percutaneous minimally invasive procedure where the vertebral body can be accessed posteriorly. The stents are implanted laterally on both sides of the spine. After positioning, the stents can be balloon-expanded inside the collapsed vertebral body restoring its original height and the natural curvature of the spine. The stents will remain in the created cavity and prevent the recollapse of the fractured vertebra after the balloons are deflated and removed. The remaining cavities can then be safely filled using a PMMA-based bone cement, resulting in pain relief as well as quick and easy patient mobilization [5, 6].
References
Feltes C, Fountas KN, Machinis T, et al (2005) Immediate and early postoperative pain relief after kyphoplasty without significant restoration of vertebral body height in acute osteoporotic vertebral fractures. Neurosurg Focus; 18(3):e5.
[No authors listed] (2002) A Survey of Stent Designs. Minim Invas Ther Allied Technol; 11(4):137147.
Fürderer S, Anders M, Schwindling B, et al (2002) [Vertebral body stenting. A method for repositioning and augmenting vertebral body compression fractures.] Orthopde; 31(4):356361. German.
Rotter R, Martin H, Fuerderer S, et al (2010) Vertebral body stenting: a new method for vertebral augmentation versus kyphoplasty. Eur Spine J; 19 (6):916923.
Alvarez L, Alkcaraz M, Prez-Higueras A, et al (2006) Percutaneous vertebroplasty: functional improvement in patients with osteoporotic compression fractures. Spine; 31(10):11131118.
Ledlie JT, Renfro MB (2006) Kyphoplasty treatment of vertebral fractures: 2-year outcomes show sustained benefits. Spine; 31(1):5764.
Instruments and stents
The new VBS small/medium/large (S/M/L) features a complete set of different stent sizes. With the available stent lengths of 13, 15, and 20 mm, it is possible to treat levels from T5 to L5 in a comprehensive range of patients anatomies.
All instruments are sterile packed, single use, and allow para- and transpedicular access either using a guide (K-) wire or a trocar. The setincludes a drill and plunger for clear intraoperative determination ofthe stent size. The cement injection cannula is designed with a special side opening for safe direction of the cement within the cavity.
One solution
VBS S/M/L can be used with vertecem V+ which is a PMMA-based bone cement ready to use right after mixing for up to 27 minutes. This allows maximum flexibility during surgery and an optimum use of OR time.
Case provided by Paul Heini, Bern, Switzerland
A 78-year-old man with back pain after a simple fall. An MRI showed a subacute fracture with a collapsed vertebral body of L1. A VB S was used for height restoration. The patient was pain-free immediately after the intervention.
Fig 1-4 Intraoperative images.
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