Do Woo-Sung, Kim Joo-Hyung, Lim Joon-Ryul, Yoon Tae-Hwan, Chun Yong-Min
Department of Orthopaedic Surgery, Arthroscopy and Joint Research Institute, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
Am J Sports Med. 2023 Mar;51(4):885-892. doi: 10.1177/03635465221149743. Epub 2023 Feb 14.
No study has evaluated whether best-fit circles based on glenoids with defects accurately represent normal inferior glenoids before injury.
To investigate whether the best-fit circles on the affected side with a glenoid defect can accurately represent native glenoids before injury.
Cohort study (diagnosis); Level of evidence, 3.
This retrospective study included 58 patients with unilateral recurrent anterior shoulder instability. First, we compared the diameter of best-fit circles based on affected and unaffected glenoids. Glenoid defect sizes based on each best-fit circle were then calculated and compared. Second, we created serial virtual glenoid defects (10%, 15%, 20%, 25%) on unaffected glenoids and compared diameters of best-fit circles on the glenoids before and after virtual defects. We also analyzed and compared the size of virtual and calculated glenoid defects. Bland-Altman plots and intraclass coefficients (ICCs) were used to compare and analyze agreement of measurements. After categorization of glenoid defects based on clinical cutoff values, Cohen κ and percentage agreement were calculated.
The diameter of 55.2% (32/58) of best-fit circles from affected glenoids over- or underestimated the diameter on the unaffected side by >5%. In 28 of the 32 patients, the diameter of the affected side circle was overestimated. Consequently, 41.4% (24/58) of glenoid defects were over- or underestimated by >5%. In 19 of the 24 patients, the glenoid defect from the affected side was >5% larger. ICCs between sides for best-fit circle diameters and defect sizes were 0.632 and 0.800, respectively. Agreement of glenoid defect size between sides was 58.6% (34/58) overall, but when the defect was ≥10%, agreement decreased to 32.3% (10/31). Among 232 glenoids with virtual defects created from 58 normal glenoids, the diameter of 31.0% (72/232) of best-fit circles and the size of 11.6% (27/232) of defects were over- or underestimated by >5%.
When assessing glenoid defects in anterior shoulder instability, best-fit circles based on affected glenoids do not always represent the native glenoid and may thus lead to inaccurate circle sizes and defect estimates.
尚无研究评估基于存在缺损的肩胛盂的最佳拟合圆是否能准确代表损伤前的正常肩胛盂下表面。
探讨存在肩胛盂缺损的患侧的最佳拟合圆是否能准确代表损伤前的天然肩胛盂。
队列研究（诊断）；证据等级，3级。
这项回顾性研究纳入了58例单侧复发性肩关节前脱位患者。首先，我们比较了基于患侧和健侧肩胛盂的最佳拟合圆的直径。然后计算并比较基于每个最佳拟合圆的肩胛盂缺损大小。其次，我们在健侧肩胛盂上创建了一系列虚拟肩胛盂缺损（10%、15%、20%、25%），并比较虚拟缺损前后肩胛盂上最佳拟合圆的直径。我们还分析并比较了虚拟肩胛盂缺损和计算得出的肩胛盂缺损的大小。采用Bland-Altman图和组内相关系数（ICC）来比较和分析测量结果的一致性。根据临床临界值对肩胛盂缺损进行分类后，计算Cohen κ系数和一致性百分比。
55.2%（32/58）的患侧肩胛盂最佳拟合圆的直径相对于健侧直径高估或低估了>5%。在这32例患者中的28例中，患侧圆的直径被高估。因此，41.4%（24/58）的肩胛盂缺损被高估或低估了>5%。在这24例患者中的19例中，患侧肩胛盂缺损大于5%。最佳拟合圆直径和缺损大小两侧之间的ICC分别为0.632和0.800。两侧肩胛盂缺损大小的总体一致性为58.6%（34/58），但当缺损≥10%时，一致性降至32.3%（10/31）。在由58个正常肩胛盂创建的232个有虚拟缺损的肩胛盂中，31.0%（72/232）的最佳拟合圆直径和11.6%（27/232）的缺损大小被高估或低估了>5%。
在评估肩关节前脱位中的肩胛盂缺损时，基于患侧肩胛盂的最佳拟合圆并不总是能代表天然肩胛盂，因此可能导致圆大小和缺损估计不准确。
