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Updated: Jun 9, 2026
12:19
Multi-Scale Modification of Metallic Implants With Pore Gradients, Polyelectrolytes and Their Indirect Monitoring In vivo
Published on: July 1, 2013
Bisphosphonate remains highly localized after elution from porous implants
Kimberly McKenzie1, J Dennis Bobyn, Jacintha Roberts
1Jo Miller Orthopaedic Research Laboratory, Montreal General Hospital, Montreal, Canada.
Clinical Orthopaedics and Related Research
|September 3, 2010
Summary
Local elution of zoledronic acid from implants primarily stays near the implant site, with minimal amounts entering the bloodstream. This localized drug delivery reduces systemic exposure and potential side effects.
Area of Science:
- Biomaterials Science
- Orthopedic Surgery
- Pharmacology
Background:
- Local elution of zoledronic acid from porous implants may improve bone formation and fixation.
- Limited data exists on the localization and systemic distribution of eluted bisphosphonates.
Purpose of the Study:
- To determine the extent of local retention versus systemic distribution of zoledronic acid eluted from porous implants.
Main Methods:
- (14)C-labeled zoledronic acid was delivered from a porous tantalum implant in canine femurs.
- Bone samples were analyzed at 6 and 52 weeks for drug concentration and distribution via scintillation spectrophotometry and autoradiography.
Main Results:
- Zoledronic acid concentration was significantly higher (two orders of magnitude) in periimplant bone compared to other tissues.
- Minute systemic distribution (≤ 7.2 ng/g) was detected throughout the skeleton.
- Autoradiography showed drug concentration highest on/within the implant, decreasing rapidly with distance.
Conclusions:
- Eluted zoledronic acid from implants remains predominantly localized.
- Minimal systemic exposure suggests reduced risk of systemic side effects and skeletal bisphosphonate burden.
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