University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
University of Pittsburgh Department of Orthopaedic Surgery, Pittsburgh, PA, USA.
J Biomech. 2022 Apr;135:111050. doi: 10.1016/j.jbiomech.2022.111050. Epub 2022 Mar 12.
The purpose of this study was to determine how implant characteristics affect in vivo shoulder kinematics after reverse shoulder arthroplasty (RSA). Kinematics of the affected upper limb were measured in 32 participants during five motions (scapular plane abduction, hand-to-head, hand-to-back, internal/external rotation at 90° abduction, and circumduction) using optical motion capture. Shoulder abduction, plane of elevation, and internal/external rotation range of motion (ROM), peak angles, and continuous kinematics waveforms were calculated for each motion. Multiple regression was used to identify associations between kinematics and implant characteristics of lateralization, humeral retroversion, glenosphere size, glenosphere tilt, glenoid eccentricity, and implant neck-shaft angle (135° or 145°). Less humeral retroversion was associated with greater shoulder rotation ROM (p = 0.036) and greater plane of elevation ROM (p = 0.024) during circumduction, while less eccentricity was associated with more posterior plane of elevation during hand-to-back (p = 0.021). The 145° implant was associated with greater internal/external shoulder rotation ROM (p < 0.001), greater internal shoulder rotation (p = 0.002), and greater plane of elevation ROM (p = 001) during the hand-to-back. The 145° implant was also associated with more internal/external rotation ROM (p = 0.043) during shoulder rotation and more abduction ROM during circumduction (p = 0.043). During the hand-to-back motion, individuals having 135° neck-shaft angle implants were more abducted from 21 to 51% of the motion and were less internally rotated from 70 to 100% of the motion, while more lateralization was associated with less internal rotation from 90 to 100% of the motion. Retroversion and implant neck-shaft angle are the primary implant characteristics associated with in vivo shoulder kinematics during complex motions after RSA.
本研究旨在确定在反肩关节置换术（RSA）后，植入物特征如何影响体内肩部运动学。通过光学运动捕捉，在 32 名参与者的五个运动（肩胛骨平面外展、手到头、手到背、90°外展时的内/外旋转以及环转）中测量受影响上肢的运动学。为每个运动计算了肩外展、抬高平面、内/外旋转活动范围（ROM）、峰值角度和连续运动学波形。使用多元回归分析确定运动学与植入物的侧移、肱骨后倾、球窝尺寸、球窝倾斜度、肩胛盂偏心度和植入物颈干角（135°或 145°）之间的关联。在环转运动中，较小的肱骨后倾与更大的肩部旋转 ROM（p=0.036）和更大的抬高平面 ROM（p=0.024）相关，而较小的偏心度与手到背时更靠后的抬高平面相关（p=0.021）。在 hand-to-back 运动中，145°植入物与更大的内/外肩部旋转 ROM（p<0.001）、更大的内肩部旋转（p=0.002）和更大的抬高平面 ROM（p=0.001）相关。145°植入物还与肩部旋转时的内/外旋转 ROM 更大（p=0.043）和环转时的外展 ROM 更大（p=0.043）相关。在 hand-to-back 运动中，颈干角为 135°的植入物个体在运动的 21%至 51%时外展度更大，在运动的 70%至 100%时内旋度更小，而更大的侧移与运动的 90%至 100%时的内旋度更小相关。后倾和植入物颈干角是 RSA 后复杂运动中与体内肩部运动学相关的主要植入物特征。
