An ex vivo biomechanical evaluation of an inflatable bone tamp used in the treatment of compression fracture.
METHODS
Ex vivo biomechanical study using osteoporotic cadaveric vertebral bodies.


OBJECTIVE
To determine if the inflatable bone tamp (tamp) restores height to compressed vertebral bodies and to compare the biomechanical properties of isolated, fractured osteoporotic vertebral bodies treated by kyphoplasty (tamp) or vertebroplasty.


BACKGROUND
Previous biomechanical studies have shown that vertebroplasty increases vertebral body strength and restores vertebral body stiffness, but does not restore vertebral body height lost as a result of compression fracture.


METHODS
Compression fractures were experimentally created in 16 osteoporotic VBs assigned to either the tamp or percutaneous vertebroplasty group. The tamp treatment consisted of inserting balloon-like devices into the vertebral body, inflating the bone tamp, and filling the void with Simplex P (Howmedica, Rutherford, NJ) bone cement. The percutaneous vertebroplasty treatment consisted of directly injecting Cranioplastic bone cement (CMW, Blackpool, UK) into the vertebral body. Pre- and posttreatment heights were measured, and the repaired vertebral bodies were recompressed to determine posttreatment strength and stiffness values.


RESULTS
The tamp treatment resulted in significant restoration (97%) of vertebral body height lost after compression, whereas percutaneous vertebroplasty treatment resulted in a significantly lower restoration of lost height (30%) (P < 0.05). Both treatments resulted in significantly stronger vertebral bodies relative to their initial state (P < 0.05). The tamp treatment restored vertebral body stiffness to initial values, but the percutaneous vertebroplasty treatment did not (P < 0.05).


CONCLUSIONS
Tamp treatment resulted in significantly greater height restoration than did percutaneous vertebroplasty, without loss of vertebral body strength or stiffness.
Belkoff
S M
SM
Orthopaedic Biomechanics Laboratory, Department of Orthopaedic Surgery, The University of Maryland, Baltimore, Maryland, USA. ebulson@jhmi.edu
Mathis
J M
JM
Fenton
D C
DC
Scribner
R M
RM
Reiley
M E
ME
Talmadge
K
K
D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D015519:Bone Density / Q000502:physiology; D018786:Bone Substitutes / Q000627:therapeutic use*; D019299:Decompression, Surgical / Q000379:methods* / Q000639:trends; D005593:Fracture Fixation, Internal / Q000379:methods* / Q000639:trends; D006801:Humans; D008875:Middle Aged; D019736:Prostheses and Implants / Q000639:trends*; D011859:Radiography; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000601:surgery*; D013131:Spine / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D016896:Treatment Outcome
D018786:Bone Substitutes