Immediate management of a stable patient with unstable pelvis

Abstract

The diagnosis of a traumatic unstable pelvis in a stable patient is a temporary concept depending on when we see the patient, as all patients presenting with hemorrhagic shock have hemodynamic stability until they become unstable. As a rule, the more unstable the pelvic fracture is, the higher the risk of bleeding and hemodynamic instability it has. Therefore, in unstable pelvic fractures, hemodynamic stability should be a diagnosis by exclusion. For bleeding detection in stable patients, an immediate one-stage contrast-enhanced CT scan is the appropriate diagnosis test; however, since CT scan radiation is always an issue, X-rays should be considered in those cases of hemodynamically stable patients in whom there is a reasonable suspicion that no unsafe bleeding is going on. Pelvic fracture classification is essential as usually there is an association between the injury mechanism, the fracture displacement, and the hemodynamic stability. Anteroposterior and, particularly, vertical traumatisms have much more proclivity to provoke major pelvic displacement and bleeding. The use of a pelvic binder, as early as possible including pre-hospital management, should be standard in high-impact blunt trauma patients independently of the trauma mechanisms. External fixation is the preferred method of stabilization in case of open fractures, and, in closed ones, when the schedule for definite osteosynthesis prolongs because of the patient's general condition. If possible, immediate percutaneous sacroiliac screw insertion for unstable pelvic fractures produce excellent results even in open fractures.

Keywords: emergency; external fixation; hemodynamic; pelvic CT scan; pelvic binder; pelvic fracture; pelvic fracture classification; sacroiliac screw.

Figure 1

Algorithm of diagnosis and treatment in patients with pelvic fracture. Pre-hospital actions are of overwhelming importance, particularly ATLS. The pelvic binder is mandatory as clinical diagnosis of pelvic fracture does not have a very accurate value. The binder must be on throughout the diagnosis and transfer steps. Once in the hospital, hemodynamically stable patients with unstable pelvic fractures would undergo either an X-ray or enhanced contrast CT scan depending on the suspicion of hemodynamic and pelvic fracture stabilities. Please refer to the text for better understanding.

Figure 2

Human pelvis is constituted by the two iliac bones and the sacrum. Posteriorly the two iliac bones are articulated together by an arthrodial synovial joint, and by strong ligaments: short ligaments (iliolumbar and sacroiliac – anterior (ASIL) and posterior) and long ligaments (sacro-sciatic ligament (SSL) and sacro-ischial ligament (SIL)). Anteriorly both iliac bones are directly joined together in the symphysis pubis (SP) by an amphiarthrosis joint with potent fibrocartilage with strong ligaments fixing the two iliac bones.

Figure 3

Young and Burgess classification of pelvic fracture. (APC) Fractures after anteroposterior compression traumatism. APC I: stable pelvis. Pure anterior diastasis <2.5 cm. Some, but not all, anterior sacroiliac and symphysis pubis ligaments must be damaged; long ligaments are intact. APC II: rotationally unstable, vertically stable. Pubic diastasis >2.5 cm, anterior disruption of sacroiliac ligaments, and diastasis of the anterior part of the sacroiliac joint, with intact posterior sacroiliac ligaments; long ligaments are disrupted. APC III: complete disruption of pubis ligaments >2.5 cm; disruption of anterior and posterior sacroiliac and long ligaments; rotational instability with vertical instability but no ascension of the iliac bone. (LC) Fractures after lateral compression traumatism. LC I: Stable pelvis. Oblique or transverse fracture of pubic rami with ipsilateral anterior compression fracture of the ala sacra. LC II: rotationally unstable, vertically stable fracture. Fracture of pubic rami with posterior fracture with dislocation of the ipsilateral iliac wing (crescent fracture). LC III: rotationally and potentially vertical unstable fracture. Ipsilateral lateral compression with contralateral anteroposterior compression (APC); this fracture is also called windswept pelvis, commonly due to an automobile rollover mechanism. (V: vertical shear) Fractures after vertical traumatism. This is the most severe rotationally and vertically unstable fracture with a higher risk of bleeding and mortality. Combined fractures are possible. The higher risk of bleeding is either the combination of a lateral external rotation (AP) with a vertical shear fracture or a bilateral vertical shear (V).

Figure 4

Tile-AO classification of pelvic fracture. A-type: fractures not affecting the biomechanical structure of the pelvis, not involving the ring. Rotationally and vertically stable. B-type: fractures with incomplete disruption of the posterior arch. Rotationally unstable and vertically stable. B1: open book-injury (external rotation). B2: lateral compression fractures (internal rotation). B2-1: ipsilateral anterior and posterior fractures. B2-2: contralateral (bucket-handle) injuries. B3: bilateral fractures. C-type: vertically unstable fractures. C1: unilateral, C2: bilateral with one side type B and the other side type C, and C3: bilateral.

Figure 5

Frequency of full-body CT scan per year for polytrauma patients prescribed by the emergency room of our hospital. The easier to perform the study was, in terms of shorter time, and the more rotation the staff had, the more cases of negative results were shown in CT scan images (from 39.72% in 2015 to 24.88% in 2022). Protocols had to be changed.

Figure 6

Inlet X-ray projection shows anteroposterior displacement of iliac bones. No abnormalities can be seen in this case with the binder on.

Figure 7

Same case as in Fig. 6. Outlet projection shows vertical displacement of iliac bones. Vertical displacement of the left hemipelvis can be seen with the binder on. The binder closes the pelvic ring.

Figure 8

Pelvic binder in a correct position.

Figure 9

Pelvic binder in an incorrect position.

Figure 10

Pelvis after anteroposterior traumatism with the binder on. No pubic diastasis can be seen.

Figure 11

Same case as in Fig. 10, without the binder. A diastasis of the symphysis pubis can be seen with an increase in the diameter of the true pelvis.

Figure 12

External fixation in a correct position. With a supracetabular positioning of pins strong purchase is obtained, and a laparotomy, if necessary, can be easily performed.

Figure 13

External fixation with incorrect pins anchorage in the iliac crest (artificial bone). Iliac wing is too thin for proper pin anchorage and the chance of weak pin purchase is very high.

Figure 14

C-clamp in the correct position (artificial bone).

Figure 15

C-clamp in a hemodynamically stable patient after laparotomy.

Figure 16

C-clamp. Medial migration of the left pin.

Figure 17

Clinical aspect of an open sacral fracture after a fall from a palm tree in a hemodynamically stable patient.

Figure 18

Same patient of Fig. 17. CT scan: ‘split’ fracture of the sacrum.

Figure 19

Same patient of Fig. 17. Immediate transiliac-transacral screws.

Figure 20

Same patient of Fig. 17. Postoperative CT scan. Proximal transiliac-transacral screw.

Figure 21

Same patient of Fig. 17. Postoperative CT scan. Distal transiliac-transacral screw.

Figure 22

Same patient of Fig. 17. Good evolution of the wound during the treatment with a vacuum system.