Centre Orthopédique Santy- Hopital Privé Jean MERMOZ, Department of Orthopaedic Surgery, 24 Avenue Paul Santy, Lyon 69008, France.
Bone Joint J. 2013 Oct;95-B(10):1377-82. doi: 10.1302/0301-620X.95B10.32012.
Osteoarthritis results in changes in the dimensions of the glenoid. This study aimed to assess the size and radius of curvature of arthritic glenoids. A total of 145 CT scans were analysed, performed as part of routine pre-operative assessment before total shoulder replacement in 91 women and 54 men. Only patients with primary osteoarthritis and a concentric glenoid were included in the study. The CT scans underwent three-dimensional (3D) reconstruction and were analysed using dedicated computer software. The measurements consisted of maximum superoinferior height, anteroposterior width and a best-fit sphere radius of curvature of the glenoid. The mean height was 40.2 mm (SD 4.9), the mean width was 29 mm (SD 4.3) and the mean radius of curvature was 35.4 mm (SD 7.8). The measurements were statistically different in men and women and had a Gaussian distribution with marked variation. All measurements were greater than the known values in normal subjects. With current shoulder replacement systems using a unique backside radius of curvature for the glenoid component, there is a risk of undertaking excessive reaming to adapt the bone to the component resulting in sacrifice of subchondral bone or under-reaming and instability of the component due to a 'rocking horse' phenomenon.
骨关节炎会导致肩胛盂尺寸发生变化。本研究旨在评估关节炎肩胛盂的大小和曲率半径。共分析了 145 例 CT 扫描，这些扫描是在 91 名女性和 54 名男性进行全肩关节置换术的常规术前评估中进行的。仅纳入患有原发性骨关节炎和同心肩胛盂的患者。对 CT 扫描进行了三维（3D）重建，并使用专用计算机软件进行了分析。测量包括肩胛盂的最大上下高度、前后宽度和最佳拟合球体曲率半径。平均高度为 40.2mm（SD4.9），平均宽度为 29mm（SD4.3），平均曲率半径为 35.4mm（SD7.8）。男女之间的测量值存在统计学差异，且具有高斯分布和明显的变异性。所有测量值均大于正常人群中的已知值。目前，使用独特的肩胛盂背面曲率半径的肩部置换系统，存在过度扩孔以适应组件的风险，从而导致软骨下骨牺牲或扩孔不足以及组件不稳定，出现“摇摆木马”现象。
