Consider Emergency Department Stress Examinations on Lateral Compression Type-1 Pelvic Ring Injuries with Complete Sacral Fractures: Commentary on an article by Graham J. DeKeyser, MD, et al.: "Emergency Department Stress Radiographs of Lateral Compression Type-1 Pelvic Ring Injuries Are Safe, Effective, and Reliable".

Abstract

Commentary A minimally displaced Young and Burgess lateral compression type-1 (LC1) pelvic fracture represents a spectrum of injury1, and treatment is controversial. Sembler Soles et al. promoted nonoperative treatment for all2, but others such as Sagi et al. have shown that some of these LC1 fractures may benefit from a surgical procedure despite their benign radiographic appearance3. This led Sagi et al. to publish their technique for examination under anesthesia (EUA) of these fractures to identify occult instability that is missed by static radiographic imaging3. However, there is concern about the unnecessary anesthetic and operative cost for fractures that are determined to be stable in the operating room (OR). Furthermore, as surgeons, we may be biased and may be more likely to fix the fractures in patients who go to the OR for an additional stress examination despite initial borderline stress examination findings. Other authors have investigated a stress examination without anesthesia. Parry et al. performed an anteroposterior pelvic radiographic examination with the patient lying on the injured side while awake in the OR prior to EUA in 20 patients and found this to reliably identify pelvic instability4. However, I have not adopted this into my practice outside the OR because of the concern for patient tolerance in the emergency room and the fact that an anteroposterior pelvic radiograph is not as sensitive as an inlet view to identify rotational displacement. In their study, DeKeyser et al. wanted to investigate if the stress examination could be performed outside the operating room with the patient awake. They present a commonsense approach to see if a rotational stress examination of an LC1 fracture in the emergency department (ED) can reliably be performed, can be tolerated by the patient, and can be trusted to direct treatment. There are 2 important things to remember about the study methods as surgeons consider adopting this protocol in their practice. First, only isolated LC1 fractures (anterior pelvic ring disruption with an ipsilateral compression sacral fracture) with <10-mm displacement on static imaging were included. Second, the rotational stress examination protocol was very specific, including how to account for magnification when measuring displacement. For those patients who had a positive stress examination and went to the OR, the rotational stress examination was repeated under anesthesia for comparison with the ED stress examination. The findings of this article are very enlightening and can help surgeons to avoid taking specific types of patients with an LC1 fracture to the operating room to perform a stress examination. All 70 patients who were enrolled tolerated the stress examination in the radiographic suite without complication. An important correlation was identified between the mechanism of injury and the rate of positive stress examination. Fifty-four percent of the patients enrolled sustained the pelvic fracture from a high-energy mechanism. As expected, high-energy fractures were significantly more likely to have positive ED stress examinations. Two (4%) of the patients who had a negative stress examination in the ED converted to the operative group because of an inability to walk after the initial stress examination. Of note, they had high-energy mechanisms of injury and bilateral fractures of the rami, but still had a negative intraoperative EUA. Both were able to mobilize after the surgical procedure. Forty-three of the patients who had a negative ED stress examination had clinical and radiographic healing with no further radiographic displacement at the 3-month follow-up, which is consistent with the findings by Whiting et al.5, and patients with a positive ED stress examination had a similar amount of displacement during the intraoperative comparison stress examination. No occult LC3 injuries were identified. Risk factors that were identified for a positive stress examination include a high-energy mechanism of injury, a complete sacral fracture, and bilateral, parasymphyseal, and comminuted rami fractures. Finally, DeKeyser et al. draw some important conclusions. First, the ED stress examination should only be considered for patients with LC1 injuries secondary to high-energy mechanisms with complete sacral fractures. Second, patients with low-energy, incomplete sacral fractures should be allowed to mobilize prior to considering a stress examination. Third, none of the positive stress examinations included instability with an external rotation stress; therefore, the external stress examination is likely unnecessary. In my practice, I already follow the nonoperative protocol for low-energy, incomplete sacral fractures, but I do plan on incorporating the ED internal rotation stress examination for minimally displaced (<10 mm of displacement) LC1 fractures involving a high-energy mechanism and a complete sacral fracture.