Microcomputed tomography assessment of glenoid component cementation techniques in total shoulder arthroplasty

Abstract

Various strategies have been described to improve glenoid component cementation technique in shoulder arthroplasty, such as the ''weephole'' technique (WH), which is thought to allow for improved cement mantles by suction venting the glenoid vault through the coracoid. The purpose of this study was to compare the cement mantle created using standard syringe pressurization (SP) to WH or a new, modified weephole technique (MWH), not requiring specific instrumentation of the coracoid medullary canal. Fourteen cadaveric scapulae underwent preparation of the glenoid to allow for implantation of glenoid components. Component fixation was achieved using SP, WH, or MWH. The volumes of cement surrounding each individual peg on the component, of the cement mantle between the back of the glenoid, and of the reamed glenoid face were quantified using micro-CT. Total shoulder arthroplasty is an efficacious treatment for advanced arthritis of the glenohumeral joint with high patient satisfaction rates. 1-5 However, glenoid component radiolucent lines and potential associated loosening are continued areas of concern. 6-9 Radiolucencies, both early and late, are common with rates ranging from 26 to 94%. 1,7,[9][10][11][12][13][14][15][16] Initially their significance was unclear; however, several studies documented progression of radiolucent lines that correlated with clinical loosening of the glenoid component, resulting in decreased function. 7,17 Changes in component design, instrumentation, and cement techniques have all been employed to improve glenoid component fixation and decrease the incidence of radiolucent lines. 6,[18][19][20] The presence of radiolucent lines on immediate postoperative films has been commonly reported. 1,9,12,[20][21][22][23][24][25] These lines are considered an indicator of technical failure or a limitation of the cement technique. 1,12,20,22,26 Gross et al. 27 suggested that the unique anatomy of the glenoid, functioning as a ''cortical box,'' with a limited amount of cancellous bone, is a significant contributing factor to the presence of postoperative radiolucent lines with the radiolucencies representing trapped fluid in the glenoid vault. They described a ''weephole'' (WH) technique for venting the vault and applying suction to improve the fluid dynamics in the glenoid vault and cement penetration into cancellous bone. 27 The technique requires the creation of a burr hole through the superior cortex of the coracoid, followed by cannulation with a curette of the glenoid vault and either the superior peg hole or keel slot depending on component design.Based upon the anatomical relationship of confluence between the medullary canal of the coracoid and the glenoid vault, we hypothesized that the vault could be vented simply by making a burr hole in the cortex of the coracoid base through which to apply suction. This would simplify the WH technique, as no further instrumentation of either the coracoid medullary canal or the glenoid vault would be required, thereby limiting the risk of pr...

Bone cement penetration pattern and primary stability testing in keeled and pegged glenoid components

“…4,9,25,39 However, only little information is available about cement penetration into the cancellous bone of the glenoid vault. 18,29 In hip and knee arthroplasty, the integrity of the bonecement interface, the degree of cement penetration, and the resultant mechanical properties have been emphasized. 15,17,24,26 In total joint replacement in general, bone quality, expressed as BMD, plays an important role in the choice of implant.…”

Pressurisation leads to better cement penetration into the glenoid bone

“…33 Other techniques for achieving deeper penetration of cement are the recently published 'weep-hole' and 'modified weep-hole technique'. 34,35 Holes were drilled into the coracoid processes and continuous suction was performed over these holes. The authors demonstrated that cement penetration was significantly deeper with the two weephole techniques than with the standard technique.…”