General considerations

For both the pelvic ring and acetabulum, patients were positioned supine on a radiolucent bed with the abdomen and ipsilateral lower extremity prepped free. The weight limit of the operating room table was checked in supermorbidly obese patients, and nitrous oxide was avoided with anesthesia because excessive bowel gas can limit fluoroscopic visualization. Intra-abdominal contrast was flushed out where possible. Patients were paralyzed during surgery. Postoperatively, patients were restricted to 3 months of toe-touch–weight bearing on the side of the pelvic ring injury or acetabular fracture.

Pelvic ring

The technique we used for percutaneous pelvic ring fixation has been well documented in the past and involves the use of a pelvic reduction frame. ( Fig. 1 ) In short, this system enables one side of the pelvis to be stabilized to the operating table, while the other can be manipulated and fine-tuned with a high degree of radiological accuracy and control. One of the strengths of this system is that it allows near-anatomic reductions of the pelvic ring, without the need for either open approaches or multiple assistants. Our standard fixation was with transsacral iliosacral screws in both S1 and S2, although this varied according to patient anatomy. For the anterior pelvic ring, the technique of fixation depended on the fracture configuration and the soft tissue envelope. Although some symphyseal disruptions were treated with a standard plate and screws, when soft tissues were poor or the fracture was open, an external fixator was used. In one case, a cerclage wire was used. Pubic ramus fractures were generally treated with column screws in this study.

( A ) Image of the pelvic reduction frame that allows for closed manipulation of pelvic ring injuries. ( B ) Clinical image demonstrating the use of the Starr Frame. The frame has been anchored to the right hemipelvis. Distal femoral skeletal traction was used on the left femur to assist with closed reduction of the displaced left hemipelvis. Note how the frame allows for appropriate C-arm positioning.

( Courtesy of Starr Frame LLC, Richardson, TX.)

Acetabulum

Screw pathways for fixing acetabular fractures are well described in the literature and are not discussed here. Reduction maneuvers can be divided into closed and open techniques. In any periarticular fracture, there are usually some capsular attachments to the joint fragments, which remain intact after the injury. If patients can be bought to the operating room within a few hours of their accident, simple fracture patterns such as transverse configurations can be reduced by manipulation of the hip. The most commonly used, of course, is in-line traction, but forced internal or external rotation, flexion, and abduction are all maneuvers that have yielded anatomic reductions for us. Clearly, as time passes, these closed reduction maneuvers become increasingly unlikely to work and most displaced acetabular fractures require some form of open reduction with mini incision.

With the hip flexed up, we perform open reductions with mini incision through a small lateral window, approximately 1 to 2 cm behind the anterior superior iliac crest. A 3- to 5-cm incision is made, and after sharply dissecting off the oblique abdominal wall muscle attachment to the crest, a Cobb elevator can be passed down the inner table directly onto the fracture fragments. In high juxta- and transtectal injuries, the fracture lines can be directly palpated with a finger through the mini lateral window, which gives an additional reading for reduction over fluoroscopy alone. Specialized pelvic reduction clamps have been designed and developed by Charles Reinert, which have sufficient excursion to allow clamping of fractures around voluminous soft tissue envelopes ( Fig. 2 ). These clamps allow for transverse fractures to be rotated and compressed, for a displaced dome fragment to be squeezed back down, and for quadrilateral plate medialization to be keyed in. The combination of traction, specific manipulation, and percutaneous clamps allows us to achieve fluoroscopically excellent reductions in most of these cases. If we think that an excellent reduction cannot be achieved minimally invasively, we treat these injuries with open internal fixation via well-described approaches. We should also stress that this approach is not straightforward surgery, particularly in those who are obese, and is a technique that has evolved at our institution over the last 10 to 15 years. Each fracture pattern is unique and requires a slightly different screw configuration and reduction maneuver. We advise surgeons who are keen to try this technique to begin with simple, less-displaced fracture patterns before moving on to more complex ones.

( A , B ) Pictures of clamps and other manipulative devices created for percutaneous management of pelvic ring injuries and acetabular fractures.

( Courtesy of Starr Frame LLC, Richardson, TX.)

Once an acceptable reduction is obtained, the fracture is stabilized with large fragment 6.5-mm or 7.3-mm cannulated screws. The choice of screw pathways is specific to the fracture configuration.

Complications

There were no infections in this group, either superficial or deep, and there were no postoperative DVTs or PEs. Three patients, in whom adequate prophylaxis was impossible, received temporary central venous filters, but all 3 filters were subsequently removed. There were no new postoperative neurologic deficits. There were 2 scheduled returns to the operating theater, for supplementary anterior fixation. One of these (patient 6) patients was a 34-year-old man with a severe AP compression (APC) type 3 injury. Having stabilized his pelvic ring posteriorly, the anterior plating was postponed by 2 weeks because of an open laparotomy wound, which extended very distally. Once his soft tissues were more compliant, the symphysis was plated, with no further complications. The second case is reported later in the section Patient 14: Case Example.

The least favorable outcome was observed in a 67-year-old lady (the oldest in this series) with moderately displaced bilateral insufficiency fractures and unilateral ramus fractures after a fall down the steps. Her BMI was 37, and it was thought initially that she could be treated nonoperatively. However, as a result of ongoing pain and further displacement observed on serial radiographs, the patient required surgery at 17 days. Bilateral posterior percutaneous iliosacral screws were passed after closed reduction with the frame, and postoperative radiographs showed some improvement (from 15 to 11 mm of displacement). However, her follow-up radiographs showed that she had “settled” back to the preinjury position. With a displacement of 16 mm at follow-up, the patient’s result was graded as “fair.”

There were no cases of heterotopic ossification (Brooker grade 2 or worse) on the last follow-up radiographs, but 3 of the 16 patients with pelvic ring injuries did undergo removal of symptomatic hardware after bony union.