The influence of implant articular thickness and glenohumeral conformity on stability of an all-metal glenoid component

J Shoulder Elbow Surg. 2007 Sep-Oct;16(5):631-9. doi: 10.1016/j.jse.2006.10.014. Epub 2007 May 15.

Abstract

The objective of this study was to determine the effect of implant thickness and glenohumeral conformity on fixation of an all-metal glenoid component. A stainless steel glenoid component was designed and implanted in 10 cadaveric scapulae. A testing apparatus capable of producing a loading vector at various angles, magnitudes, and directions was used. The independent variables included 6 directions and 3 angles of joint load, 3 implant thicknesses, and 4 glenohumeral conformities. Implant micromotion relative to bone was measured by use of 4 displacement transducers at the superior, inferior, anterior, and posterior sites. The components displayed a consistent response to loading of ipsilateral compression and contralateral distraction. Stability decreased as the load application angle increased (P < .05). A decrease in the implant thickness and glenohumeral conformity resulted in increased implant stability (P < .05). Decreasing implant thickness and glenohumeral conformity reduce the eccentric component of loading and may improve the durability of glenoid implants.

MeSH terms

  • Biomechanical Phenomena
  • Cadaver
  • Compressive Strength
  • Humans
  • Joint Instability / prevention & control
  • Joint Prosthesis*
  • Materials Testing
  • Probability
  • Prosthesis Design*
  • Sensitivity and Specificity
  • Shoulder Joint / surgery