BACKGROUND: Reverse total shoulder arthroplasty (rTSA) has been used to treat patients with irreparable rotator cuff dysfunction. Despite the proven clinical efficacy, there is minimal information regarding the underlying changes to the shoulder kinematics associated with this construct. Therefore, we sought to examine the kinematics of dynamic shoulder motion in patients with well-functioning rTSA. METHODS: We tested 12 healthy subjects and 17 patients with rTSA. All rTSA patients were able to elevate their arms to at least 90° and received the implant as the primary arthroplasty at least 6 months before testing. On average, the rTSA patients elevated their arms to 112° ± 12° (mean ± SD) and reported an American Shoulder and Elbow Surgeons outcome score of 90.6 ± 6.3. A 3-dimensional electromagnetic motion capture device was used to detect the dynamic motion of the trunk, scapula, and humerus during bilateral active shoulder elevation along the sagittal, scapular, and coronal planes. RESULTS: In both healthy and rTSA shoulders, the majority of the humeral-thoracic motion was provided by the glenohumeral motion. Therefore, the ratio of glenohumeral to scapulothoracic (ST) motion was always greater than 1.62 during elevation along the scapular plane. In comparison to healthy subjects, however, the contribution of ST motion to overall shoulder motion was significantly increased in the rTSA shoulders. This increased contribution was noted in all planes of shoulder elevation and was maintained when weights were attached to the arm. CONCLUSION: Kinematics of the rTSA shoulders are significantly altered, and more ST motion is used to achieve shoulder elevation.
BACKGROUND: Reverse total shoulder arthroplasty (rTSA) has been used to treat patients with irreparable rotator cuff dysfunction. Despite the proven clinical efficacy, there is minimal information regarding the underlying changes to the shoulder kinematics associated with this construct. Therefore, we sought to examine the kinematics of dynamic shoulder motion in patients with well-functioning rTSA. METHODS: We tested 12 healthy subjects and 17 patients with rTSA. All rTSA patients were able to elevate their arms to at least 90° and received the implant as the primary arthroplasty at least 6 months before testing. On average, the rTSA patients elevated their arms to 112° ± 12° (mean ± SD) and reported an American Shoulder and Elbow Surgeons outcome score of 90.6 ± 6.3. A 3-dimensional electromagnetic motion capture device was used to detect the dynamic motion of the trunk, scapula, and humerus during bilateral active shoulder elevation along the sagittal, scapular, and coronal planes. RESULTS: In both healthy and rTSA shoulders, the majority of the humeral-thoracic motion was provided by the glenohumeral motion. Therefore, the ratio of glenohumeral to scapulothoracic (ST) motion was always greater than 1.62 during elevation along the scapular plane. In comparison to healthy subjects, however, the contribution of ST motion to overall shoulder motion was significantly increased in the rTSA shoulders. This increased contribution was noted in all planes of shoulder elevation and was maintained when weights were attached to the arm. CONCLUSION: Kinematics of the rTSA shoulders are significantly altered, and more ST motion is used to achieve shoulder elevation.
Authors: L Nalbone; R Adelfio; M D'Arienzo; T Ingrassia; V Nigrelli; F Zabbara; P Paladini; F Campi; A Pellegrini; G Porcellini Journal: Musculoskelet Surg Date: 2013-05-30
Authors: Giovanni Merolla; Ilaria Parel; Andrea Giovanni Cutti; Maria Vittoria Filippi; Paolo Paladini; Giuseppe Porcellini Journal: Int Orthop Date: 2018-08-10 Impact factor: 3.075
Authors: Giovanni Merolla; Francesco Cuoghi; George S Athwal; Ilaria Parel; Maria V Filippi; Andrea G Cutti; Elisabetta Fabbri; Antonio Padolino; Paolo Paladini; Fabio Catani; Giuseppe Porcellini Journal: Int Orthop Date: 2021-07-01 Impact factor: 3.075
Authors: Jonathan Wright; Christopher Potts; Mark P Smyth; Lisa Ferrara; John W Sperling; Thomas W Throckmorton Journal: Int J Shoulder Surg Date: 2015 Apr-Jun
Authors: Ryan A Smith; Katherine Woolley; Augustus Mazzocca; Richard Feinn; Mark Cote; Gregg Gomlinski; Juan Garbalosa; Karen M Myrick Journal: J Orthop Date: 2020-04-30