The effects of dynamic compressive loading on biodegradable implants of 50-50% polylactic acid-polyglycolic acid

Douglas E. Thompson, C. Mauli Agrawal, Kyriacos Athanasiou

Research output: Contribution to journalArticle

49 Citations (Scopus)

Abstract

Biodegradable implants that release growth factors or other bioactive agents in a controlled manner are investigated to enhance the repair of musculoskeletal tissues. In this study, the in vitro release characteristics and mechanical properties of a 50:50 polylactic acid/polyglycolic acid two phase implant were examined over a 6-week period under no-load conditions or under a cyclic compressive load, such as that experienced when walking slowly during rehabilitation. The results demonstrated that a cyclic compressive load significantly slows the decrease of molecular chain size during the first week, significantly increases protein release for the first 2-3 weeks, and significantly stiffens the implant for the first 3 weeks. It was also shown that protein release is initially high and steadily decreases with time until the molecular weight declines to about 20% of its original value (approximately 4 weeks). Once this threshold is reached, increased protein release, surface deformation, and mass loss occurs. This study also showed that dynamic loading and the environment in which an implant is placed affect its biodegradation. Therefore, it may be essential that in vitro degradation studies of these or similar implants include a dynamic functional environment.

Original languageEnglish (US)
Pages (from-to)61-74
Number of pages14
JournalTissue Engineering
Volume2
Issue number1
StatePublished - 1996
Externally publishedYes

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Absorbable Implants
Polyglycolic Acid
Proteins
Acids
Walking
Intercellular Signaling Peptides and Proteins
Membrane Proteins
Rehabilitation
Molecular Weight
Biodegradation
Patient rehabilitation
Repair
Molecular weight
Tissue
Degradation
Mechanical properties
poly(lactic acid)
In Vitro Techniques

ASJC Scopus subject areas

  • Biophysics
  • Cell Biology

Cite this

The effects of dynamic compressive loading on biodegradable implants of 50-50% polylactic acid-polyglycolic acid. / Thompson, Douglas E.; Mauli Agrawal, C.; Athanasiou, Kyriacos.

In: Tissue Engineering, Vol. 2, No. 1, 1996, p. 61-74.

Research output: Contribution to journalArticle

Thompson, Douglas E. ; Mauli Agrawal, C. ; Athanasiou, Kyriacos. / The effects of dynamic compressive loading on biodegradable implants of 50-50% polylactic acid-polyglycolic acid. In: Tissue Engineering. 1996 ; Vol. 2, No. 1. pp. 61-74.
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