Instituto de Ortopedia e Traumatologia, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil.
American Hip Institute, Westmont, Illinois, USA Hinsdale Orthopedics, Westmont, Illinois, United States of America.
PLoS One. 2018 Jun 21;13(6):e0199352. doi: 10.1371/journal.pone.0199352. eCollection 2018.
This study sought to investigate the association between tomographic femoroacetabular impingement (FAI) angles and histologically evaluated labral tears. The authors hypothesized that cadavers presenting with cam and pincer morphologies would present a higher prevalence of acetabular labral tears.
Twenty fresh cadavers were submitted to computed tomography. Standard FAI angles were measured, including the alpha angle, femoral version, acetabular version, Tonnis angle and center-edge angle. A cam lesion was defined as an alpha angle greater than 50o. A pincer lesion was defined as a center-edge angle greater than 40o, a Tonnis angle less than 0o or acetabular version less than 0o. After dissection, three fragments of each acetabulum, corresponding to the antero-superior, superior and postero-superior acetabular rim, were obtained. These fragments were submitted to routine histological preparation. Each slide was evaluated for possible labral tears. Tears were classified according to their Seldes type.
The mean age of the cadavers was 50.2 years (SD: 7.4; 13 males). Sixteen (80%) of the cadavers had a cam lesion, and eight cadavers (40%) had a pincer lesion. Histologically, 16 (80%) of the cadavers had a labral tear in at least one region. According to the Seldes classification, 60.7% and 28.6% of these labral tears were type 1 and type 2, respectively. A mixed type of labral tear (10.7%), which represented a new form of Seldes tear, was described. Cadavers with a labral tear had significantly higher alpha angles than other cadavers (53.29o vs 49.33o, p = 0.01). Pincer lesions were not associated with labral tears. We found no association between pincer or cam lesions and Seldes classification.
Cadavers presenting with higher alpha angles had a higher incidence of labral tears. No association was found between FAI and Seldes classification.
This study demonstrated a high prevalence of FAI abnormalities associated with histological alterations in a cadaveric sample. Joint damage may be present in the early stages of FAI.
本研究旨在探讨关节断层摄影股骨髋臼撞击症（FAI）角度与组织学评估的髋臼唇撕裂之间的关系。作者假设，呈现凸轮和钳夹形态的尸体将表现出更高的髋臼唇撕裂发生率。
20 具新鲜尸体进行计算机断层扫描。测量了标准的 FAI 角度，包括 alpha 角、股骨版本、髋臼版本、Tonnis 角和中心边缘角。凸轮病变定义为 alpha 角大于 50o。钳夹病变定义为中心边缘角大于 40o、Tonnis 角小于 0o 或髋臼版本小于 0o。解剖后，从每个髋臼获得三个对应于前上、上和后上髋臼缘的碎片。这些碎片被提交进行常规组织学准备。对每个载玻片进行可能的髋臼唇撕裂评估。根据 Seldes 类型对撕裂进行分类。
尸体的平均年龄为 50.2 岁（标准差：7.4；男性 13 名）。16 具（80%）尸体存在凸轮病变，8 具（40%）尸体存在钳夹病变。组织学上，16 具（80%）尸体在至少一个区域存在髋臼唇撕裂。根据 Seldes 分类，这些髋臼唇撕裂中有 60.7%和 28.6%分别为 1 型和 2 型。描述了一种新的 Seldes 撕裂形式，即混合类型的髋臼唇撕裂（10.7%）。有髋臼唇撕裂的尸体的 alpha 角明显高于其他尸体（53.29o 与 49.33o，p = 0.01）。钳夹病变与髋臼唇撕裂无关。我们没有发现钳夹或凸轮病变与 Seldes 分类之间存在关联。
alpha 角较高的尸体出现髋臼唇撕裂的发生率较高。FAI 与 Seldes 分类之间没有关联。
本研究在尸体样本中证明了与组织学改变相关的高 FAI 异常发生率。关节损伤可能在 FAI 的早期阶段存在。
