Here is the finish to the post on pelvic fractures. In my previous post, I discussed some basics to pelvic anatomy and the anterior-posterior patterns (D - F in the figure below) of fracture in the pelvis. In this post, I will briefly describe the lateral compression patterns (A - C) of pelvic fractures and then also discuss the vertical sheer pattern (G).
Also, worth review in this post is the importance of identifying pelvic fractures early in the trauma evaluation. This is one injury that orthopaedic surgeons that treat which is truly life threatening. Early identification of these injuries can save lives in the trauma bay. It is always rewarding to get called to a trauma, look at an AP pelvis and note a pelvic fracture, and then go into the trauma bay to see that the patient is hypotensive and tachycardic, put a binder on the pelvis and watch the heart rate decrease and the patient become more normotensive. Closing that pelvic space is something that must be done ASAP because it can make a huge difference in the hemodynamic status of the patient.
There are three types of lateral compression (LC) fractures in the Young-Burgess Classification. These injuries occur due to a compressive force on the lateral side of the body. The type of injury seen depends on where the force is applied. In this type of injury, the ligaments responsible for pelvic stability become shortened. Pubic ramus fractures often accompany LC fractures and can be on the ipsilateral or contralateral side.
LC I - This injury pattern results in compression of the sacrum. This injury pattern is often associated with transverse pubic ramus fractures.
LC II - In this injury pattern, a posterior iliac wing fracture is noted. Depending on the amount of disruption to the posterior ligamentous structures, varying amounts of instability will be noted. This injury pattern, however, is a stable pattern of injury in the vertical plane.
LC III - This is the so-called windswept pelvis. In this pattern, either an LC I or LC II injury pattern is noted, but the force transmitted by the lateral compression results in an APC injury on the contralateral side. Of note, this injury pattern is especially vulnerable to circulatory damage and hemorrhagic shock.
Treatment of LC pelvic injuries is similar to those of APC type injuries. Treatment is selected based on the stability of the injury In general, non-operative treatment can be selected for patients with <1.5cm of displacement of the posterior ring or ramus fractures with no posterior displacement. Gross displacement of hemodynamic instability can necessitate more aggressive treatment ranging from angiography and coiling of arterial lesions to operative fixation.
Vertical Sheer (VS) injuries are the result of a vertically applied force due to a fall on an outstretched extremity. This injury results in disruption of the symphysis and the posterior ligaments. This is a very unstable injury pattern and often results in cephaloposterior displacement of the pelvis. VS injuries are often associated with vascular compromise and hemodynamic instability. Operative fixation will likely be required to close down the sympyseal diastasis and the posterior ring in addition to aggressive resuscitation to maintain perfusion of vital organs.
These injury patterns do not often occur as a single entity. Combination type injuries are possible.
As I mentioned in the previous post, it is important to be cognizant of DVT prophylaxis in the setting of a pelvic injury. Other injury associations include bladder and urethral injuries in men. Because of this , it is important to send urine to look for red blood cells which might indicate damage to the urinary system. If a urethral injury is present, the patient will need intervention ranging from a Foley catheter and observation to operative repair.
In the next post, we'll take a look at acetabular fractures, their classification, and discuss a little bit on their treatment.