Achieving fixation in glenoids with superior wear using reverse shoulder arthroplasty

Posterior Glenoid Wear in Total Shoulder Arthroplasty: Eccentric Anterior Reaming Is Superior to Posterior Augment

“…The synthetic scapulae we used provided a more homogenous test bed than cadaveric specimens, and they are more anatomically relevant than foam blocks as used in previous studies [8,23,33]. Although fatigue testing is not defined for this model, this substrate (fourthgeneration composite bones) has been shown to have similar biomechanical properties to human bone [20,41,42] and has been used by others for glenoid prosthesis testing [34]. Despite their homogeneity, the methods used to manufacture the synthetic scapulae result in circularshaped weak zones in the cortical shell.…”

Avoiding superior tilt in reverse shoulder arthroplasty: a review of the literature and technical recommendations

“…29 Aside from using bone graft augments or medializing with correct version and tilt and using a lateralized glenosphere, a third option is the use of glenosphere baseplates with superior augments. 45 As clinical data are currently scarce, it remains to be seen if this implant design is a prosthetic solution that will eliminate the need for bone grafting in some cases of superior erosion.…”

The effect of glenoid bone loss on reverse shoulder arthroplasty baseplate fixation

“…Management of glenoid bone loss with use of RSA has evolved, with a variety of surgical techniques and advancements in prosthetic designs being introduced during the past 15 years. 7,9,17 Because RSA designs universally use a metal baseplate with peripheral screw fixation, obtaining secure fixation together with opportunities for bone graft fixation is enhanced. Eccentric reaming is often required during glenoid preparation, as the glenoid baseplate requires a matched surface for optimal fixation and ultimate osseous integration.…”

“…They found both techniques to have similar fixation throughout cyclic loading, maintaining micromotion below the 150-mm threshold for implant-bone ingrowth. 17 The clinical results of augmented baseplates in RSA, however, have yet to be reported.…”

“…Test specimens were cycled through a 55 arc of motion at 1 Hz while the test frame's actuator applied a constant 750 N compressive force through a glenosphere size-matched humeral component polyethylene neutral liner, in similar fashion to the methods adopted by previous authors. 16,17 The test block's orientation was such that the 55 arc of motion occurred in the scapular plane defined by the location of superior wear in the experimental groups, thus serving to approximate a 25 to 80 humeral abduction motion relative to a fixed scapula. 18 Thus, our cyclic test setup simulates the primary abduction motion generated by the deltoid in RSA.…”