■肱骨头的解剖修复对于成功进行肩关节置换至关重要。肱骨头的精确测量对于解剖置换至关重要。
■为了评估肱骨头的最佳合眼圆根据不同的平面射线照片投影,可以预测左肩或右肩的肱骨头植入物的大小。
■描述性实验室研究。
■评估了200例无关节病或其他肱骨头异常发现的患者的双侧肩片。基于3个点获得最佳拟合圆:解剖颈部的内侧和外侧端点以及大结节下方的外侧皮质。这个圆圈是在5个不同的射线照相投影上绘制的(肩前后[AP],关节盂AP,出口,腋窝,和30°的尾部倾斜)的左肩和右肩的每个病人,并测量每个圆的半径。使用组内相关系数(ICC)对左右肩部之间最佳拟合圆半径的一致性进行统计分析。有2名独立的盲化观察者进行两次测量以评估观察者之间和观察者之间的可靠性。
■右肩和左肩之间半径的总体一致性非常好(所有ICC≥0.990)。根据影像学检查,肩部AP的ICC为0.990(95%CI,0.986-0.993),关节盂AP为0.992(95%CI,0.989-0.995),出口为0.996(95%CI,0.994-0.997),腋窝0.994(95%CI,0.991-0.996),30°尾侧倾斜为0.993(95%CI,0.990-0.995)。观察者ICC表现出很高的精确度:肩部AP为0.987(95%CI,0.978-0.993),关节盂AP为0.986(95%CI,0.974-0.992),出口为0.974(95%CI,0.954-0.985),腋窝0.991(95%CI,0.984-0.995),30°尾侧倾斜为0.987(95%CI,0.977-0.993)。观察者ICC表现出出色的重测可靠性:肩部AP为0.983(95%CI,0.970-0.991),关节盂AP为0.989(95%CI,0.980-0.994),出口为0.987(95%CI,0.978-0.993),腋窝0.985(95%CI,0.973-0.991),30°尾侧倾斜为0.970(95%CI,0.947-0.983)。
■能够从平射线照片的不同投影确定计算肱骨头植入物理想尺寸的最佳拟合圆。
■可以使用从平片获得的对侧肱骨头的最佳拟合圆实现变形肱骨头的解剖恢复。该方法可以促进肩关节解剖修复的术前计划和术后评估,避免过度填塞的问题。
UNASSIGNED: Anatomic restoration of the humeral head is critical for successful shoulder replacement. Accurate measurements of the humeral head are essential for anatomic substitution.
UNASSIGNED: To evaluate whether a best-fit circle of the humeral head, as determined from different projections of plain radiographs, can predict the humeral head implant size for either the left or right shoulder.
UNASSIGNED: Descriptive laboratory study.
UNASSIGNED: Bilateral shoulder radiographs of 200 patients without arthropathy or other abnormal findings of the humeral head were evaluated. The best-fit circle was obtained based on 3 points: the medial and lateral endpoints of the anatomic neck and the lateral cortex below the greater tuberosity. This circle was drawn on 5 different radiographic projections (shoulder anteroposterior [AP], glenoid AP, outlet, axillary, and 30° caudal tilt) of the left and right shoulders of each patient, and the radius of each circle was measured. Agreement in the best-fit circle radius between the left and right shoulders was statistically analyzed using the intraclass correlation coefficient (ICC). There were 2 independent blinded observers who performed each measurement twice to evaluate inter- and intraobserver reliability.
UNASSIGNED: Overall agreement in the radius between the right and left shoulders was excellent (all ICCs ≥0.990). The ICCs according to the radiographic view were 0.990 (95% CI, 0.986-0.993) for shoulder AP, 0.992 (95% CI, 0.989-0.995) for glenoid AP, 0.996 (95% CI, 0.994-0.997) for outlet, 0.994 (95% CI, 0.991-0.996) for axillary, and 0.993 (95% CI, 0.990-0.995) for 30° caudal tilt. Interobserver ICCs demonstrated a high level of precision: 0.987 (95% CI, 0.978-0.993) for shoulder AP, 0.986 (95% CI, 0.974-0.992) for glenoid AP, 0.974 (95% CI, 0.954-0.985) for outlet, 0.991 (95% CI, 0.984-0.995) for axillary, and 0.987 (95% CI, 0.977-0.993) for 30° caudal tilt. Intraobserver ICCs demonstrated excellent test-retest reliability: 0.983 (95% CI, 0.970-0.991) for shoulder AP, 0.989 (95% CI, 0.980-0.994) for glenoid AP, 0.987 (95% CI, 0.978-0.993) for outlet, 0.985 (95% CI, 0.973-0.991) for axillary, and 0.970 (95% CI, 0.947-0.983) for 30° caudal tilt.
UNASSIGNED: The best-fit circle to calculate the ideal size of a humeral head implant was able to be determined from different projections of plain radiographs.
UNASSIGNED: Anatomic restoration of a deformed humeral head can be achieved using the best-fit circle of the contralateral humeral head as obtained from plain radiographs. This method can facilitate preoperative planning and postoperative evaluation in the anatomic restoration of the shoulder to avoid the problems of overstuffing.