Orthopaedic Biomechanics Laboratory, VA Long Beach Healthcare System (09/151), 5901 East 7th. Street , Long Beach, CA, 90822, USA.
Ewha Womans University, Seoul, Korea.
Knee Surg Sports Traumatol Arthrosc. 2018 Jan;26(1):48-55. doi: 10.1007/s00167-016-4312-x. Epub 2016 Sep 26.
Estimation of anterior glenoid bone loss is important for surgical decision-making. The purpose of this study was to describe a method for estimating anterior glenoid bone loss.
Thirty-nine cadaveric glenoids were digitized to obtain glenoid geometry. Glenoid bare spot centre, arthroscopic centre, and centre of the inferior glenoid circle relative to the geometric centre were measured. To simulate anterior glenoid bone loss, imaginary sequential osteotomies were created 0°, 22.5°, and 45° to the superior-inferior line in a 3D digitizing programme. Per cent of anterior glenoid bone loss area was calculated as the percentage of defect area relative to the entire area of the glenoid. The relationship between area loss and ratio of bone defect length to the distance from posterior glenoid to various centres was determined.
As the ratio of bone defect length to the distance from posterior glenoid to all three centres increased, the per cent area of bone loss increased exponentially. The ratio using the inferior circle centre and arthroscopic centre was highly correlated to the actual glenoid bone loss in all osteotomies (R > 0.90). The ratio using the centre of bare area had the lowest correlation. The ratio of defect length to distance from posterior glenoid to arthroscopic centre greater than 2.4 for 0° and 2.0 for 45° osteotomies results in bone loss area greater than 25 %. The bare area centre had the largest variation. Average bone loss was overestimated when the centre of bare spot was used compared to other centre locations.
Per cent of anterior glenoid bone loss can be estimated using the ratio of bone defect length to the distance from posterior glenoid rim to the centre of inferior glenoid circle or arthroscopic centre either preoperatively using 3D CT or arthroscopically which can be useful for determining surgical treatment.
评估前盂肱关节盂骨丢失对于手术决策很重要。本研究旨在描述一种评估前盂肱关节盂骨丢失的方法。
对 39 个尸体肩盂进行数字化处理以获得肩盂的几何形状。测量肩盂裸区中心点、关节镜中心点和下盂肱关节圈中心点相对于几何中心点的位置。在 3D 数字化程序中，模拟从前向后的骨切开线以 0°、22.5°和 45°相对于上-下方向，创建假想的连续骨切开线。通过将缺陷区域的百分比除以盂肱关节盂的整个区域来计算前盂肱关节骨丢失的百分比。确定面积损失与骨缺损长度与后盂肱关节到各个中心点的距离之比之间的关系。
随着骨缺损长度与后盂肱关节到所有三个中心点的距离之比的增加，骨丢失面积呈指数增长。在所有骨切开术中，使用下盂肱关节圈中心点和关节镜中心点的比值与实际的盂肱关节骨丢失高度相关（R>0.90）。使用裸区中心点的比值相关性最低。对于 0°和 45°的骨切开术，当骨缺损长度与后盂肱关节到关节镜中心点的距离之比大于 2.4 时，会导致骨丢失面积大于 25%。裸区中心点的变化最大。与其他中心点位置相比，使用裸区中心点会高估平均骨丢失。
术前使用 3D CT 或关节镜检查，可以通过测量骨缺损长度与后盂肱关节缘到下盂肱关节圈中心点或关节镜中心点的距离之比来估计前盂肱关节盂骨丢失的百分比，这对于确定手术治疗方案可能很有用。
