Impact of polyethylene glenoid cementation technique on cement mantle integrity and stability after cyclic loading: a computed tomography and biomechanical study.

Background: There are no generally accepted guidelines for polyethylene (PE) glenoid component cementation techniques. In particular, it is not known whether the backside of a PE glenoid should be fully or partially cemented-or not cemented at all. We hypothesized that cementing techniques would have an impact on cement mantle volume and integrity, as well as biomechanical stability, measured as micromotion under cyclic loading.

Intraoperative assembly of anatomical shoulder prosthesis frequently results in malalignment of the modular taper junction.

Anatomical shoulder arthroplasties (ASA) may fail because of micromotion at the modular taper junction causing wear due to fretting. Sufficient taper strength can reduce micromotion and potential reasons for failure. However, there are no normative standards for a safe assembly process performed intraoperatively by the surgeon.

The effect of vitamin E-enhanced cross-linked polyethylene on wear in shoulder arthroplasty-a wear simulator study.

Background: Wear of the polyethylene glenoid component and subsequent particle-induced osteolysis remains one of the most important modes of failure of total shoulder arthroplasty. Vitamin E is added to polyethylene to act as an antioxidant to stabilize free radicals that exist as a byproduct of irradiation used to induce cross-linking. This study was performed to assess the in vitro performance of vitamin E-enhanced polyethylene compared with conventional polyethylene in a shoulder simulator model.

Wear-induced loss of mass in reversed total shoulder arthroplasty with conventional and inverted bearing materials.

The notching phenomenon is one of the major concerns with reversed total shoulder arthroplasty. Repetitive contact between the humeral implant and the scapula (mechanical notching) produces progressive abrasion of the implant if the moving part is made of polyethylene. Its debris may then lead to active osteolysis (biological notching).