Description:
Flamingo stress views to assess pelvic stability. These views are used to detect true instability at the symphysis pubis, i.e. failure of the passive stabilisers sufficient to allow ≥ 2mm vertical displacement across the symphysis under load. Optimal radiographic technique therefore requires all dynamic stabilisers on the non-weight bearing side to be ‘switched off’. Standard manuals of radiographic technique often describe a method in which some degree of hip flexion is used (as illustrated in the drawing on the left), but this at a minimum recruits the iliopsoas and is therefore partially self-defeating. The author instead advocates a simple ‘hanging leg’ technique (illustrated in the drawing on the right) in which the patient must be carefully coached to relax all supporting muscles on the hanging side to ensure maximal loading of the symphysial ligaments. The Xray example here shows gross pelvic instability using the ‘hanging leg’ technique. The method of measuring vertical shift at the symphysis pubis on flamingo views is critical.
