Height restoration and preservation in osteoporotic vertebral compression fractures: a biomechanical analysis of standard balloon kyphoplasty versus radiofrequency kyphoplasty in a cadaveric model.
METHODS
Biomechanical cadaver study.


OBJECTIVE
The aim of the present study was to evaluate 2 different methods with respect to height restoration and preservation in a cadaver model under cyclic loading.


BACKGROUND
Standard balloon kyphoplasty (BKP) represents a well-established treatment opportunity for osteoporotic vertebral compression fractures. BKP was developed to restore vertebral height and improve sagittal alignment. Its use has grown significantly over the last 2 decades. In contrast, distinct biomechanical data are missing. Within the last few years, several alternative techniques with regard to height restoration have emerged, such as radiofrequency kyphoplasty (RFK).


METHODS
Twenty-five vertebral bodies of 2 female cadavers with secured osteoporosis were examined. Standardized vertebral wedge compression fractures were created. Afterward, 2 groups were randomly assigned: 12 vertebral bodies were treated with BKP and 13 vertebral bodies by RFK under a preload of 100 N. Then the vertebral bodies underwent cyclic loading (100,000 cycles, 100 to 600 N, 5 Hz). Anterior, central, and posterior vertebral body heights were evaluated by CT scans.


RESULTS
Anterior height was reduced after fracture 6.3 mm (SD 3) for the BKP group and 7.2 mm (SD 3) in the RFK group (P>0.1). After treatment, the difference in the initial anterior height was 4.5 mm (SD 2) for the BKP group and 4.7 mm (SD 3) for the RFK group (P>0.1). After cyclic loading, the difference was 5.3 mm (SD 3) for the BKP group and 5.2 mm (SD 3) for the RFK group (P>0.1). The average cement volume used was 8.7 mL (SD 1) for the BKP group and 4.8 mL (SD 2) for the RFK group (P<0.0001).


CONCLUSIONS
On the basis of our results, the unipedicular RFK in osteoporotic compression fractures might represent a promising alternative for the clinical setting.
Departments of *Trauma, Hand and Reconstructive Surgery †Orthopedics and Rheumatology, University Hospital Giessen and Marburg, Philipps University of Marburg, Marburg, Germany.
Ludwig
L
Oberkircher
Johannes
J
Struewer
Christopher
C
Bliemel
Benjamin
B
Buecking
Daphne-Asimenia
DA
Eschbach
Steffen
S
Ruchholtz
Antonio
A
Krueger
D001696:Biomechanical Phenomena / Q000502:physiology; D001843:Bone Cements / Q000627:therapeutic use; D002102:Cadaver; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D050815:Fractures, Compression / Q000601:surgery*; D006801:Humans; D058498:Kyphoplasty / Q000379:methods*; D008159:Lumbar Vertebrae / Q000502:physiology / Q000601:surgery; D010024:Osteoporosis / Q000601:surgery; D058866:Osteoporotic Fractures / Q000601:surgery*; D016103:Spinal Fractures / Q000601:surgery*; D013904:Thoracic Vertebrae / Q000502:physiology / Q000601:surgery; D014057:Tomography, X-Ray Computed; D016474:Weight-Bearing / Q000502:physiology
D001843:Bone Cements