Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2017 Nov;26(11):2754-2762.
doi: 10.1007/s00586-017-5062-2. Epub 2017 Apr 8.

Osseointegration improves bone-implant interface of pedicle screws in the growing spine: a biomechanical and histological study using an in vivo immature porcine model

Kanako Shiba  1 , Hiroshi Taneichi  2 , Takashi Namikawa  1 , Satoshi Inami  1 , Daisaku Takeuchi  1 , Yutaka Nohara  1
Affiliations

Osseointegration improves bone-implant interface of pedicle screws in the growing spine: a biomechanical and histological study using an in vivo immature porcine model

Kanako Shiba et al. Eur Spine J. 2017 Nov.

Abstract

Purpose: Implant failure is a frequent complication in corrective surgery for early onset scoliosis, since considerable forces are acting on small and fragile vertebrae. Osseointegration showing biomechanical and histological improvement in bone-implant interface (BII) after dental implant placement has been well investigated. However, there are no studies regarding osseointegration in immature vertebral bone. The purpose was to evaluate the timecourse of biomechanical and histological changes at BII after pedicle screw placement using in vivo immature porcine model.

Methods: Ten immature porcine were instrumented with titanium pedicle screws in the thoracic spine. After a 0-, 2-, 4-, and 6-month survival periods, the spines were harvested at the age of 12 months. Histological evaluation of BII was conducted by bone volume/tissue volume (BV/TV) and bone surface/implant surface (BS/IS) measurements. Bone mineral density (BMD) measurement and biomechanical testing of BII were done.

Results: Contact surface and bone volume around the screw threads were significantly increased over the time. BV/TV and BS/IS were improved with statistically significant differences between 0- and ≥4-month (p ≤ 0.001) periods. BMD in all subjects was determined to be the same (p ≥ 0.350). Pullout strength was also increased over time with significant differences between 0- and ≥2-month (p ≤ 0.011) periods.

Conclusion: Improved stability at BII caused by osseointegration was confirmed by in vivo immature porcine model. A two-stage operation is proposed based on the osseointegration theory, in which an implant is installed in advance in the vertebrae at the first stage and deformity correction surgery is performed after sufficient stability is obtained by osseointegration at a later stage.

Keywords: Early onset scoliosis; Growing rod; Osseointegration; Osteotomy; Porcine model.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

References

    1. Angle Orthod. 2009 May;79(3):558-63 - PubMed
    1. J Bone Joint Surg Am. 1980 Sep;62(6):964-73 - PubMed
    1. J Bone Joint Surg Am. 2008 Dec;90(12):2695-706 - PubMed
    1. Int J Oral Maxillofac Implants. 1999 Mar-Apr;14(2):189-96 - PubMed
    1. J Pediatr Orthop. 2001 Jul-Aug;21(4):549-55 - PubMed

LinkOut - more resources