The influence of implant articular thickness and glenohumeral conformity on stability of an all-metal glenoid component.
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.
Bicknell
Ryan T
RT
Department of Surgery, University of Western Ontario, London, Ontario, Canada. rtbickne@yahoo.ca
Liew
Allan S L
AS
Danter
Matthew R
MR
Patterson
Stuart D
SD
King
Graham J W
GJ
Chess
David G
DG
Johnson
James A
JA
D001696:Biomechanical Phenomena; D002102:Cadaver; D019245:Compressive Strength; D006801:Humans; D007593:Joint Instability / Q000517:prevention & control; D007595:Joint Prosthesis; D008422:Materials Testing; D011336:Probability; D011474:Prosthesis Design; D012680:Sensitivity and Specificity; D012785:Shoulder Joint / Q000601:surgery