Morattel Boris, Bonin Nicolas
Orthopaedic Surgeon, Lyon Ortho Clinic, 29B Avenue des sources, Lyon 69009, France.
J Hip Preserv Surg. 2021 Jun 23;8(Suppl 1):i25-i33. doi: 10.1093/jhps/hnab026. eCollection 2021 Jun.
Femoro-acetabular impingement (FAI), is the result of an abnormal morphology of the hip joint. On the femoral side, asphericity of the head can be highlighted by an alpha angle measurement >50° on computed tomography or MRI. However, some particular cephalic asphericities can make it difficult to measure the alpha angle, leading to a diagnostic pitfall. While in the classic cam effect, the deformity is peripheral and can be treated by arthroscopic femoroplasty, an apical head deformity remains a therapeutic challenge. We present the case of a 17-year-old male patient with a femoral head deformity, corresponding to an ISHA zone 6 overhang, significantly improved in everyday and sports life by arthroscopic trapdoor technique to resect the focal central deformity while enabling concomitant treatment of central compartment pathology, in this case, a hypertrophic ligamentum teres and femoral head chondral flap. Etiology of this femoral head deformity remains uncertain but could be a particular cam deformity, sequelae to pediatric disease or instability with repeated traction of the ligament teres on the femoral head apical insertion during cephalic growth.
股骨髋臼撞击症（FAI）是髋关节形态异常的结果。在股骨侧，通过计算机断层扫描或磁共振成像上α角测量值>50°可突出显示股骨头的非球形。然而，一些特殊的头部非球形可能会使α角测量变得困难，从而导致诊断陷阱。在经典的凸轮效应中，畸形位于周边，可通过关节镜下股骨成形术治疗，而顶端头部畸形仍然是一个治疗挑战。我们报告一例17岁男性患者，其股骨头畸形对应于国际髋关节镜学会（ISHA）6区悬垂，通过关节镜活板门技术切除局灶性中央畸形，同时能够对中央腔室病变（在本例中为肥厚性圆韧带和股骨头软骨瓣）进行同期治疗，患者在日常生活和运动中得到显著改善。这种股骨头畸形的病因仍不确定，但可能是一种特殊的凸轮畸形、儿科疾病的后遗症或在股骨头生长期间圆韧带反复牵拉股骨头顶端插入处导致的不稳定。
