St Joseph's University Medical Center, Paterson, New Jersey, USA.
University of Colorado Boulder, Department of Integrative Physiology, Boulder, Colorado, USA.
Am J Sports Med. 2019 Oct;47(12):2978-2984. doi: 10.1177/0363546519871065. Epub 2019 Sep 6.
Femoroacetabular impingement (FAI) and acetabular dysplasia lead to acetabular cartilage damage that commonly results in the chondral flaps seen during hip arthroscopy.
To compare the acetabular chondral flap morphology seen during hip arthroscopy ("outside-in" vs "inside-out") with clinical and radiographic parameters underlying FAI and hip dysplasia.
Cohort study; Level of evidence, 3.
Patients who underwent hip arthroscopy by the senior author between 2013 and 2017 with a finding of Outerbridge grade IV acetabular chondral flap were included. Each procedure was retrospectively reviewed on video and chondral flaps were categorized as inside-out or outside-in. An inside-out designation was made for flaps exhibiting an intact chondrolabral junction with a detached sleeve of chondrolabral tissue from the central acetabulum, and an outside-in designation was made for centrally anchored flaps exhibiting a break in the chondrolabral junction. Radiographic markers of hip impingement/dysplasia were noted for each patient during assignment into 1 of 2 radiographic groups: group 1, lateral center edge angle (LCEA) >20 with FAI, and group 2, LCEA ≤20 with or without cam FAI. Associations between chondral flap morphology and clinical diagnosis were tested using a chi-square test.
Overall, 95 patients (103 hips) were included (group 1, 78 hips; group 2, 25 hips). Among hips in group 2, 24 had concurrent cam FAI. There was a significant relationship between chondral flap type and radiographic diagnosis ( < .001). Among group 1 hips, 78% exhibited outside-in type chondral flaps, 12% exhibited combined outside-in and inside-out flaps, and 10% exhibited inside-out flaps. Group 2 hips showed 72% inside-out type chondral flaps, 16% combined, and 12% outside-in. Hips exhibiting outside-in type flaps were significantly more likely to be in group 1 (positive predictive value [PPV], 91%; negative predictive value [NPV], 69%). Similarly, hips exhibiting inside-out type flaps were significantly more likely to be in group 2 (PPV, 56%; NPV, 95%). Altogether, 90% of group 1 hips exhibited an outside-in lesion and 88% of group 2 hips exhibited an inside-out lesion.
Acetabular chondral flap type visualized during hip arthroscopy correlates with radiographic markers of hip impingement and hip instability. Outside-in flaps are highly predictive of FAI, whereas inside-out flaps are highly predictive of acetabular dysplasia.
股骨髋臼撞击症（FAI）和髋臼发育不良导致髋臼软骨损伤，通常会导致髋关节镜检查中所见的软骨瓣。
比较髋关节镜检查中所见的髋臼软骨瓣形态（“外向内”与“内向外”）与 FAI 和髋关节发育不良的临床和影像学参数。
队列研究；证据水平，3 级。
纳入 2013 年至 2017 年间由资深作者行髋关节镜检查且存在髋臼软骨瓣 Outerbridge 分级 IV 级的患者。对每个手术过程进行视频回顾，并根据有无软骨盂唇结合部完整而中央附着的软骨瓣将软骨瓣分为“外向内”或“内向外”。如果存在软骨盂唇结合部完整而中央附着的软骨瓣，且伴有从髋臼中央分离的软骨盂唇组织袖套，则诊断为“外向内”；如果存在中央附着的软骨瓣，且软骨盂唇结合部有破裂，则诊断为“内向外”。在将每位患者归入以下 2 个影像学组之一时，注意髋关节撞击/发育不良的影像学标志物：组 1，外侧中心边缘角（LCEA）＞20°伴 FAI；组 2，LCEA≤20°伴或不伴凸轮 FAI。使用卡方检验检验软骨瓣形态与临床诊断之间的相关性。
共有 95 例患者（103 髋）纳入研究（组 1，78 髋；组 2，25 髋）。在组 2 中，24 髋合并凸轮 FAI。软骨瓣类型与影像学诊断显著相关（<.001）。在组 1 髋中，78%表现为“外向内”型软骨瓣，12%表现为“外向内和内向外”混合型软骨瓣，10%表现为“内向外”型软骨瓣。组 2 髋中，72%为“内向外”型软骨瓣，16%为混合型，12%为“外向内”型。表现为“外向内”型软骨瓣的髋更有可能在组 1（阳性预测值 [PPV]，91%；阴性预测值 [NPV]，69%）。同样，表现为“内向外”型软骨瓣的髋更有可能在组 2（PPV，56%；NPV，95%）。总的来说，组 1 髋中 90%为“外向内”型病变，组 2 髋中 88%为“内向外”型病变。
髋关节镜检查中所见的髋臼软骨瓣类型与髋关节撞击和髋关节不稳定的影像学标志物相关。“外向内”型软骨瓣高度提示 FAI，而“内向外”型软骨瓣高度提示髋臼发育不良。
