I. Azboy , Department of Orthopaedics and Traumatology, Istanbul Medipol University School of Medicine, Istanbul, Turkey I. Azboy, H. H. Ceylan, H. Groff, H. Vahedi, J. Parvizi, The Rothman Institute at Thomas Jefferson University, Philadelphia, PA, USA.
Clin Orthop Relat Res. 2019 May;477(5):983-989. doi: 10.1097/CORR.0000000000000699.
Bilateral symptomatic femoroacetabular impingement (FAI) is common. However, the fate of asymptomatic hip in patients with the radiographic diagnosis of bilateral FAI and unilateral symptoms remains unknown.
QUESTIONS/PURPOSES: (1) What is the likelihood of the asymptomatic hip becoming painful in patients with unilateral symptoms but with radiographic evidence of bilateral femoroacetabular impingement? (2) What radiological and clinical factors are associated with the development of symptoms in an asymptomatic hip diagnosed with FAI?
A longitudinally maintained institutional FAI database was queried to collect relevant data for this retrospective study. To answer our research questions, we created a cohort of patients with bilateral radiographic signs of FAI but only unilateral symptoms at the time of initial presentation. Between 2004 and 2016, a senior surgeon (JP) at one institution treated 652 patients for hip pain determined to be from FAI, a diagnosis we made based on clinical symptoms, physical exam, and diagnostic imaging. We excluded 95 patients (15%) because of inadequate data or other diagnoses, which left 557 patients. Of those, 170 patients (31%) had bilateral radiological diagnosis of FAI, and 88 (52%) of them had bilateral hip symptoms, and so were excluded. Of the remaining 82 patients, eight (10%) underwent bilateral FAI surgery under the same anesthetic despite having only unilateral symptoms, leaving 74 for analysis in this study. Patients were followed with annual clinic visits, or contacted by phone and electronically. We defined onset of symptoms using a modified Harris Hip Score (mHHS) or the University of California at Los Angeles (UCLA) activity scale, and used a logistic regression model to identify factors associated with the development of symptoms.
Of the 74 patients with bilateral FAI and an asymptomatic hip at initial presentation, 60 (81%) became symptomatic at a mean 2 years (range, 0.3-11 years) followup. Of these 60 patients, 43 (72%) eventually underwent subsequent surgical intervention. After controlling for potential confounding variables such as sex, age, BMI, history of trauma we identified that reduced neck-shaft angle (r = -0.243, p = 0.009), increased lateral center-edge angle (r = 0.123, p = 0.049), increased alpha angle (r = 0.069, p = 0.025), and younger age (r = -0.071, p = 0.046) were associated with the development of symptoms in the contralateral hip. With the numbers available, none of the other examined variables such as sex, BMI, history of trauma, psychiatric condition, employment, Tönnis grade, Tönnis angle, crossover sign, type of impingement, and joint congruency were found to be associated with symptom progression.
Bilateral FAI may be observed about one-third of patients. Most patients with unilateral symptomatic FAI and radiographic diagnosis of bilateral FAI in this cohort became symptomatic relatively quickly and most of them underwent subsequent surgical intervention in the contralateral hip. Reduced neck-shaft angle, increased lateral center-edge angle, increased alpha angle, and younger age were associated with symptom development in the contralateral hip. Hip preservation surgeons may use the finding of this study to counsel patients who present with bilateral FAI but only unilateral symptoms about the natural history of their condition.
Level III, therapeutic study.
双侧症状性股骨髋臼撞击症（FAI）很常见。然而，对于影像学诊断为双侧 FAI 且单侧有症状的患者，无症状髋的结局仍不清楚。
问题/目的：（1）单侧症状但影像学显示双侧 FAI 的患者，无症状髋出现疼痛的可能性有多大？（2）与无症状髋 FAI 的发展相关的影像学和临床因素有哪些？
我们通过回顾性研究，对一家机构长期维护的 FAI 数据库进行了查询，以收集相关数据。为了回答我们的研究问题，我们创建了一个队列，该队列包括影像学显示双侧 FAI 但初次就诊时只有单侧症状的患者。在 2004 年至 2016 年间，一家机构的一位资深外科医生（JP）治疗了 652 名因 FAI 导致髋痛的患者，我们根据临床症状、体格检查和诊断性影像学检查做出了 FAI 的诊断。我们排除了 95 名（15%）因数据不足或其他诊断而不符合条件的患者，这使得我们有 557 名患者符合研究条件。在这些患者中，有 170 名（31%）有双侧影像学诊断的 FAI，其中 88 名（52%）有双侧髋部症状，因此被排除在外。在剩余的 82 名患者中，有 8 名（10%）尽管只有单侧症状，仍在同一次麻醉下接受了双侧 FAI 手术，因此有 74 名患者可用于本研究分析。我们通过年度门诊就诊或电话和电子方式对患者进行随访。我们使用改良 Harris 髋关节评分（mHHS）或加利福尼亚大学洛杉矶分校（UCLA）活动量表来定义症状的出现，并使用逻辑回归模型来确定与症状发展相关的因素。
在 74 名初始表现为双侧 FAI 且无症状的患者中，60 名（81%）在平均 2 年（范围为 0.3-11 年）的随访中出现症状。在这 60 名患者中，有 43 名（72%）最终接受了后续手术干预。在控制性别、年龄、BMI、创伤史等潜在混杂因素后，我们发现颈干角减小（r = -0.243，p = 0.009）、外侧中心边缘角增加（r = 0.123，p = 0.049）、α角增加（r = 0.069，p = 0.025）和年龄较小（r = -0.071，p = 0.046）与对侧髋部症状的发展相关。在现有的数据中，我们没有发现其他检查的变量，如性别、BMI、创伤史、精神状况、就业、Tönnis 分级、Tönnis 角、交叉征、撞击类型和关节匹配度，与症状进展相关。
大约三分之一的患者可能会出现双侧 FAI。在本队列中，大多数单侧有症状性 FAI 且影像学诊断为双侧 FAI 的患者很快出现症状，大多数患者随后在对侧髋部接受了手术干预。颈干角减小、外侧中心边缘角增加、α角增加和年龄较小与对侧髋部症状的发展相关。髋关节保护外科医生可以利用本研究的发现，为仅单侧有症状且影像学显示双侧 FAI 的患者提供有关其病情自然史的咨询。
III 级，治疗性研究。
