Department of Radiology, University of Wisconsin School of Medicine and Public Health, 600 Highland Ave, Madison WI 53792, USA.
AJR Am J Roentgenol. 2012 Oct;199(4):894-900. doi: 10.2214/AJR.11.8211.
Iliopsoas impingement is a new arthroscopic diagnosis that refers to an anterior labral injury caused by the iliopsoas tendon. Currently, there are no preoperative criteria to establish the diagnosis of iliopsoas impingement. The goal of this study was to determine whether there are imaging criteria that would identify iliopsoas impingement on preoperative MR arthrography.
This study compared the preoperative MR arthrograms of 23 patients who had iliopsoas impingement diagnosed at hip arthroscopy with the arthrograms of 24 patients who did not have iliopsoas impingement found at hip arthroscopy. All of the arthroscopies were performed by a single orthopedic hip surgeon. In all cases of impingement, there was an isolated injury to the labrum at the 3-o'clock position. All were treated by arthroscopic iliopsoas tenotomy performed at the labral level. The MR examinations of the 47 patients were evaluated independently by two musculoskeletal radiologists who were blinded to the diagnosis. The following characteristics of the iliopsoas tendon at the level of the anterior labrum were evaluated: lateral dip, increased signal intensity (SI) between the iliopsoas tendon and labrum, irregularity of the deep margin of the iliopsoas tendon, edema within the iliopsoas tendon or capsule at the 3-o'clock position, presence of a labral tear at the 3-o'clock position, dimensions of the iliopsoas tendon, and location of iliopsoas tendon as it passed the labrum. Statistical analysis was performed using the Kruskal Wallis test, Fisher exact test, and Cohen kappa. Values for p less than 0.05 were considered significant.
Nineteen women (mean age, 35 years) and four men (mean age, 36 years) had central iliopsoas impingement. Sixteen women (mean age, 38 years) and eight men (mean age, 35 years) did not have central iliopsoas impingement (p=0.318). For the impingement and nonimpingement groups, lateral dip of the iliopsoas tendon was seen in 15 of 23 (65%) and 17 of 24 (71%) for reader 1 and 18 of 23 (78%) and 11 of 24 (46%) for reader 2, respectively (p=0.76 and 0.036, respectively). There was no difference between the groups for increased SI between the iliopsoas tendon and labrum (p=0.38 and 0.82, respectively), irregular deep margin of the iliopsoas tendon (p=0.61 and 0.35, respectively), thickness of the iliopsoas tendon (p=0.33), or tendon or capsule edema (p=0.37 and 0.77, respectively). Reader 1 found 20 of 23 and reader 2 18 of 23 labral tears at the 3-o'clock position in the iliopsoas impingement group, with 13 of 24 and 10 of 24 in the non-iliopsoas impingement group respectively (p=0.024 and 0.017, respectively). The combined iliopsoas tendon width for both readers was 10.2 mm (range, 8.1-14.3 mm) in women and 11.9 mm (range, 11.1-13.4 mm) in men in the iliopsoas impingement group (p=0.0285), and 11.0 mm (range, 9.0-12.6 mm) for women and 11.8 mm (range, 8.7-15.1 mm) for men in the non-iliopsoas impingement group (p=0.159). The iliopsoas tendon most commonly crossed the labrum at the 3-o'clock position in both groups (p=0.83-0.17).
An acetabular labral tear at the 3-o'clock position should suggest the diagnosis of iliopsoas impingement.
髂腰肌撞击症是一种新的关节镜诊断，指的是由髂腰肌肌腱引起的前唇损伤。目前，还没有术前标准来确定髂腰肌撞击症的诊断。本研究的目的是确定术前磁共振关节造影术是否存在可识别髂腰肌撞击症的影像学标准。
本研究比较了 23 例经髋关节镜检查诊断为髂腰肌撞击症患者的术前磁共振关节造影和 24 例经髋关节镜检查未发现髂腰肌撞击症患者的关节造影。所有的关节镜检查均由一位骨科髋关节外科医生完成。在所有的撞击病例中，均存在 3 点钟位置的盂唇孤立性损伤。所有患者均采用关节镜下髂腰肌肌腱切开术治疗。47 例患者的 MRI 检查由 2 位独立的肌肉骨骼放射科医生进行评估，他们对诊断结果不知情。评估的髂腰肌肌腱在髋臼唇水平的以下特征：外侧倾斜，髂腰肌肌腱和髋臼唇之间的信号强度增加，髂腰肌肌腱的深缘不规则，3 点钟位置的髂腰肌肌腱或囊内水肿，3 点钟位置存在盂唇撕裂，髂腰肌肌腱的尺寸，以及髂腰肌肌腱穿过髋臼唇的位置。使用 Kruskal Wallis 检验、Fisher 确切检验和 Cohen kappa 进行统计分析。p 值小于 0.05 被认为具有统计学意义。
19 名女性（平均年龄，35 岁）和 4 名男性（平均年龄，36 岁）存在中央髂腰肌撞击症。16 名女性（平均年龄，38 岁）和 8 名男性（平均年龄，35 岁）不存在中央髂腰肌撞击症（p=0.318）。在撞击组和非撞击组中，髂腰肌肌腱外侧倾斜在第 1 位读者中分别为 15 例（65%）和 17 例（71%），在第 2 位读者中分别为 18 例（78%）和 11 例（46%）（p=0.76 和 0.036）。两组之间髂腰肌肌腱和髋臼唇之间的信号强度增加（p=0.38 和 0.82）、髂腰肌肌腱的深缘不规则（p=0.61 和 0.35）、髂腰肌肌腱的厚度（p=0.33）或肌腱或囊内水肿（p=0.37 和 0.77）均无差异。第 1 位读者在髂腰肌撞击组中发现 23 例中的 20 例和第 2 位读者发现 18 例髋臼唇 3 点钟位置撕裂，在非髂腰肌撞击组中分别发现 24 例中的 13 例和 24 例中的 10 例（p=0.024 和 0.017）。两位读者的髂腰肌肌腱总宽度在女性中为 10.2mm（范围，8.1-14.3mm），在男性中为 11.9mm（范围，11.1-13.4mm），在髂腰肌撞击组中为 11.0mm（范围，9.0-12.6mm），在非髂腰肌撞击组中为 11.8mm（范围，8.7-15.1mm）（p=0.0285）。髂腰肌肌腱最常见的是在两组中在 3 点钟位置穿过髋臼唇（p=0.83-0.17）。
髋臼唇 3 点钟位置的撕裂应提示髂腰肌撞击症的诊断。
