Comparison of biomechanical properties of periosteal suture fixation and bone anchor fixation to the pubic bone.
OBJECTIVE
To compare the relative strength of fixation using bone anchors (BAs) compared with direct suture placement into the periosteum.


METHODS
The anterior bony pelvis was harvested from 21 female cadavers. In each pelvis, BA suture fixation was performed using Cinch anchors on one side of the pubic bone and direct periosteal suture fixation (PSF) on the contralateral side of the same pelvis. We used No. 1 polyproprolene suture for all cases. Using a hydraulic mechanical testing machine, all specimens were loaded in uniaxial tension until failure.


RESULTS
Failure modes for BA-fixed pelves were as follows: 11 BA pull-out, 1 midsuture failure, and 9 suture cut by BA. Failure modes for the PSF pelves were as follows: 6 suture pull-outs through the bone, 14 midsuture failures, and 1 suture cut at the bone. PSF pelves required significantly higher loads to induce failure compared with BA pelves (PSF 92.63 +/- 22.62 N, BA 71.32 +/- 19.76 N, P <0.0002). In many cases, both PSF and BA were adequate points of fixation, and the major mechanism of failure was suture rupture. In pelves with suture failure, the load to induce failure was significantly higher in the PSF group (PSF 105.06 +/- 12.55 N, BA 86.06 +/- 7.78 N, P <0.0025). When the suture failed, PSF was better because BA fixation actually broke some sutures. The load required to induce failure was higher in the PSF groups in 19 (90.5%) of 21 pelves.


CONCLUSIONS
Biomechanical testing using permanent monofilament suture did not demonstrate a superiority of BA suture fixation to PSF fixation. PSF appears superior, since BAs induced suture failure in many cases.
Winters
J C
JC
Department of Urology, Ochsner Clinic, Louisiana State University Medical Center, New Orleans, Louisiana, USA.
Fontenot
C
C
Glowacki
C
C
Thomas
K A
KA
Scarpero
H
H
D001696:Biomechanical Phenomena; D002102:Cadaver; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D016268:Internal Fixators; D010521:Periosteum; D011630:Pubic Bone; D013536:Suture Techniques