Department of Traumatology and Sports Injuries, Paracelsus Medical University Salzburg, Muellner Hauptstrasse 48, Salzburg, Austria.
Am J Sports Med. 2010 Jun;38(6):1188-95. doi: 10.1177/0363546510361951. Epub 2010 Apr 1.
Biplane radiologic evaluation is indispensable for the correct diagnosis of acute acromioclavicular (AC) joint injuries. Thus far, no functional radiographic techniques have been quantified to evaluate horizontal instability in acute AC joint dislocations.
Supine dynamic axillary lateral shoulder views detect horizontal instability of the distal clavicle in patients with acute AC joint dislocations.
Cohort study (Diagnosis); Level of evidence, 2.
Twenty-five consecutive patients with a mean age of 39 +/- 14 years with acute AC joint injury underwent biplane radiologic evaluation, including a conventional Zanca view and an axillary lateral view in a sitting position. In addition, supine axillary lateral views with the arm in 90 degrees of abduction and 60 degrees of flexion and extension were taken to evaluate the horizontal dynamics of the distal clavicle. The gleno-acromio-clavicular angle (GACA) was introduced and used to quantify the horizontal clavicular dynamics in terms of angle differences. The unaffected shoulders served as the control group.
Superior dislocation of the lateral clavicle in the Zanca view was classified as Rockwood type II in 7 patients, type III in 15, and type V in 3. The axillary lateral view in a sitting position showed posterior dislocation of the distal clavicle in 8 patients (Rockwood type IV injury). Dynamic radiologic evaluation revealed an average GACA difference between the neutral and anterior position of the arm of 7.1 degrees +/- 5.5 degrees for the unaffected shoulder. In the injured AC joints, 11 patients showed no radiologic evidence of horizontal instability (group A) with a GACA difference of 7.1 degrees +/- 4.8 degrees . Increased anteroposterior translation was evident in 14 patients (group B) with a GACA difference of 30.3 degrees +/- 14.3 degrees (P < .001).
Functional axillary radiologic evaluation seems to represent a simple imaging tool to reveal dynamic horizontal instability.
Horizontal instability of the distal clavicle in acute AC joint injuries represents an indication for surgical treatment. Dynamic axillary radiologic evaluation may detect previously missed unstable injuries. This evaluation might be relevant when deciding on surgical AC joint stabilization.
双平面放射学评估对于急性肩锁关节（AC）损伤的正确诊断是必不可少的。迄今为止，尚无功能放射学技术来量化评估急性 AC 关节脱位的水平不稳定性。
仰卧位动态腋侧肩位视图可检测急性 AC 关节脱位患者锁骨远端的水平不稳定。
队列研究（诊断）；证据水平，2。
连续 25 例平均年龄 39 +/- 14 岁的急性 AC 关节损伤患者接受双平面放射学评估，包括常规 Zanca 视图和坐姿腋侧视图。此外，还采用仰卧腋侧视图，手臂外展 90 度，屈曲和伸展 60 度，以评估锁骨远端的水平动态。引入肩锁关节角（GACA），并使用角度差异来量化锁骨的水平动力学。未受影响的肩部作为对照组。
Zanca 视图中外侧锁骨的向上脱位在 7 例中被分类为 Rockwood Ⅱ型，在 15 例中为 Ⅲ型，在 3 例中为 Ⅴ型。坐姿腋侧视图显示 8 例患者锁骨远端后脱位（Rockwood Ⅳ型损伤）。动态放射学评估显示，未受影响的肩部中立位和前位手臂的平均 GACA 差异为 7.1 度 +/- 5.5 度。在受伤的 AC 关节中，11 例患者无水平不稳定的放射学证据（A 组），GACA 差异为 7.1 度 +/- 4.8 度。14 例患者出现明显的前后移位（B 组），GACA 差异为 30.3 度 +/- 14.3 度（P <.001）。
功能腋侧放射学评估似乎是一种简单的影像学工具，可以显示动态水平不稳定。
急性肩锁关节损伤中锁骨远端的水平不稳定是手术治疗的指征。动态腋侧放射学评估可能会发现以前错过的不稳定损伤。在决定是否进行 AC 关节稳定手术时，这种评估可能具有相关性。
