Implant impingement during internal rotation after reverse shoulder arthroplasty. The effect of implant configuration and scapula anatomy: A biomechanical study

Factors affecting internal rotation following total shoulder arthroplasty

“…Of the 46 studies, only one mentioned the effects of cup depth on IR, noting IR improved with a shallow cup. 27 …”

“…Of studies examining lateralization, 7 of 13 found that lateralization of the glenosphere improved IR. 5 , 24 , 27 , 28 , 30 , 44 , 50 Of the 6 whose results did not agree with the majority, 3 looked specifically at boney increase-offset RSA (BIO-RSA), which increases glenosphere lateralization through the use of a bone graft. These studies found BIO-RSA did not improve IR when compared to standard RSA.…”

Extension of the shoulder is essential for functional internal rotation after reverse total shoulder arthroplasty

“…Improving active and passive internal rotation after RTSA has been the focus of various biomelc hanica 1,2,4,6,14,16,19,20,[22][23][24][25][26][27]30,32,33,43,45 and clinical 5,21,[35][36][37]39,42,44 studies. The most important finding of our study is that active extension of at least 40 is a prerequisite for satisfactory fIR after RTSA.…”

“…21,37,38 In recent years, various biomechanical studies have analyzed factors influencing fIR. These studies suggest that lateralization of the center of rotation, 20,27,30 inferior positioning of the baseplate, 32,43 a decreased glenosphere size, 28 a decreased humeral insert thickness, 24,41 a neck-shaft angle < 155 , 25 an intact subscapularis, 29 and humeral retrotorsion < 20 16,19,23 are positively associated with fIR after RTSA. The interpretation of their findings, however, does not explain the clinical loss of fIR after RTSA.…”

Analyse des facteurs influençant la rotation interne de l’épaule après mise en place d’une prothèse inversée

“…Dans la littérature, les études essentiellement biomécaniques ou cadavériques montrent que les éléments importants pour avoir une bonne RI sont le débord glénoïdien inférieur [3][4][5][6][7][8][9][10][11][12][13], un insert en PE peu profond [16], une inclinaison humérale moins importante que 155° [17], une rétroversion humérale peu importante [18][19]. Une taille de la sphère plus importante améliorerait la RI1 pour Berhouet et al [18], mais pas pour Langhor et al [20].…”