Is Sacral Dysmorphism Protective Against Spinopelvic Dissociation? Multicenter Case Series.

OBJECTIVES: Investigate the incidence of sacral dysmorphism (SD) in patients with spinopelvic dissociation (SPD). DESIGN: Retrospective case series. SETTING: Two academic level 1 trauma centers. PATIENTS/PARTICIPANTS: One thousand eight hundred fifty adult patients with sacral and pelvic fractures (OTA/AO 61-A, B, C). INTERVENTION: Plain pelvic radiographs and CT scans. MAIN OUTCOME MEASUREMENTS: Incidence of SD in patients with SPD. Secondary radiographic evaluation of fracture classification and deformity on sagittal imaging. RESULTS: Eighty-two patients with SPD were identified, and 12.2% displayed features of SD, significantly less than reported in the literature. The S2 sacral body was the most common horizontal fracture location in patients with SD and nondysmorphic sacra (ND). Roy-Camille type I patterns were more common in ND (35%), versus type II in SD patients (40%). SD patients had lower body mass indexes (19.7 vs. 25.2, P = 0.001). Segmental kyphosis (22.5 degrees ND vs. 23.8 degrees SD, P = 0.838) and sacral kyphosis (26 degrees ND vs. 31 degrees SD, P = 0.605) were similar between groups. Percutaneous fixation was the most common surgical technique. CONCLUSIONS: We report a significantly lower prevalence of SD in patients with SPD than previously reported in the literature. This suggests that variations in sacral osseous anatomy alter force transmission across the sacrum during traumatic loading, which may be protective against certain high-energy fracture patterns. Preoperative evaluation of sacral anatomy is critical, not only in determining the size and orientation of sacral segment safe zones for screw placement, but also to better understand the pathomechanics involved in sacral trauma. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Management of Pelvic Fractures.

Pelvic fractures are often the result of high-energy trauma and can result in significant morbidity. Initial management is focused on patient resuscitation and stabilization given the potential for life-threatening hemorrhage that is associated with these injuries. Radiographic evaluation and classification of the pelvic injury guides initial management, provisional stabilization, and preoperative surgical planning. Definitive reduction and fixation of the posterior and anterior pelvic ring is sequentially performed to restore stability and allow for mobilization and healing. Open techniques are commonly used for the pubic symphysis and displaced anterior and posterior ring injuries for which an acceptable reduction is unable to be obtained with closed or indirect techniques. Percutaneous fixation has become increasingly more common for both the anterior and posterior ring and utilizes screw placement within the osseous fixation pathways of the pelvis.

Complications Associated With Pelvic External Fixation.

An external fixator is an essential tool for treating unstable pelvic ring injuries but its use carries risks, including pin-site infections and injury to the lateral femoral cutaneous nerve (LFCN). Surgeons currently lack data regarding these risks for patient counseling. This study aimed to identify the incidence of and risk factors for superficial and deep pin-site infection and LFCN damage. Fifty-two patients who underwent pelvic external fixation with anterior pin placement as part of definitive treatment for unstable pelvic ring disruption were retrospectively evaluated to identify factors associated with the development of infection. Ten (19%) patients developed superficial pin-site infections, with none developing a deep infection. Five were treated with oral antibiotics alone, 5 with additional intravenous antibiotics, and 1 underwent superficial surgical debridement at the time of external fixator removal. Three (6%) patients had temporary symptoms consistent with irritation to their LFCN that all resolved by 3 months. One (2%) patient had residual mild and intermittent LFCN dysesthesias at the 6-month follow-up. Adjusted logistic regression models identified no specific factors that were associated with increased risk of infection. The incidence of superficial infections related to pelvic external fixation was 19%, which can usually be treated with antibiotics with low risk of deep infection. In addition, there remains a low risk of long-term LFCN damage. Patients should be counseled on these risks during the perioperative period. [Orthopedics. 2017; 40(6):e959-e963.].

Percutaneous manipulation of intra-articular debris after fracture-dislocation of the femoral head or acetabulum.

Traumatic fracture-dislocation of the hip usually warrants prompt management by closed manipulative reduction. In some patients, debris malpositioned between the femoral head and the acetabular dome obstructs a completely concentric reduction of the injured hip. To avoid damage to the articular surfaces, the debris between them should be removed in a timely fashion. Techniques for removal include open approaches with or without fracture fixation or hip arthroscopy. Fracture fixation and hip arthroscopy have associated risks and potential complications, may require special equipment, and may not be familiar to all surgeons. The authors present a simple fluoroscopically guided technique for the percutaneous removal of intra-articular debris between the femoral head and the acetabular dome after traumatic femoral head or acetabular fracture-dislocation.

Anatomic Determinants of Sacral Dysmorphism and Implications for Safe Iliosacral Screw Placement.

BACKGROUND: Upper sacral segment dysplasia increases the risk of cortical perforation during iliosacral screw insertion. Dysmorphic sacra have narrow and angled upper osseous corridors. However, there is no validated definition of this anatomic variation. We hypothesized that pelves could be quantitatively grouped by anatomic measurements. METHODS: One hundred and four computed tomography (CT) scans and virtual outlet views of uninjured pelves were analyzed for the presence of the five qualitative characteristics of upper sacral segment dysplasia. CT scans were reformatted to measure the cross-sectional area, angulation, and length of the osseous corridor. Principal components analysis was used to identify multivariable explanations of anatomic variability, and discriminant analysis was used to assess how well such combinations can classify dysmorphic pelves. RESULTS: The prevalences of the five radiographic qualitative characteristics of upper sacral segment dysplasia, as determined by two reviewers, ranged from 28% to 53% in the cohort. The rates of agreement between the two reviewers ranged from 70% to 81%, and kappa coefficients ranged from 0.26 to 0.59. Cluster analysis revealed three pelvic phenotypes based on the maximal length of the osseous corridor in the upper two sacral segments. Forty-one percent of the pelves fell into the dysmorphic cluster. The five radiographic qualitative characteristics of dysmorphism were significantly more frequent (p < 0.007) in this cluster. A combination of upper sacral coronal and axial angulation effectively explained the variance in the data, and an inverse linear relationship between these angles and a long upper sacral segment corridor was identified. A sacral dysmorphism score was derived with the equation: (first sacral coronal angle) + 2(first sacral axial angle). An increase in the sacral dysmorphism score correlated with a lower likelihood of a safe transsacral first sacral corridor. No subjects with a sacral dysmorphism score >70 had a safe transsacral first sacral corridor. CONCLUSIONS: Sacral dysmorphism was found in 41% of the pelves. The major determinants of sacral dysmorphism are upper sacral segment coronal and axial angulation. The sacral dysmorphism score quantifies dysmorphism and can be used in preoperative planning of iliosacral screw placement.

Antegrade femoral nailing in acetabular fractures requiring a Kocher-Langenbeck approach.

Ipsilateral displaced acetabular and femoral shaft fractures represent a dilemma for orthopedic surgeons because antegrade femoral nailing may complicate a Kocher-Langenbeck acetabular exposure. The goals of this study were to review the results of ipsilateral femoral and acetabular fractures treated with antegrade femoral nailing and a Kocher-Langenbeck approach and to evaluate the assertion that this treatment strategy is associated with increased morbidity. This was a retrospective cohort study at a regional Level I trauma center. Sixteen patients with a femoral fracture treated with antegrade nailing and an ipsilateral acetabular fracture treated with a Kocher-Langenbeck approach were identified. One patient died as a result of his injuries, and 2 were not available for long-term follow-up. One had a deep infection requiring irrigation, debridement, and intraveonous antibiotics. One patient developed a hematoma requiring irrigation and debridement. At final follow-up, 2 patients had no heterotopic ossification about the hip, 4 had Brooker class I heterotopic ossification, 3 had Brooker class II heterotopic ossification, 2 had Brooker class III heterotopic ossification, and 2 patients had Brooker class IV heterotopic ossification requiring excision. Ipsilateral femoral and acetabular fractures represent a rare and severe injury constellation. Antegrade nailing of the femur with ipsilateral Kocher-Langenbeck exposure for fixation of the acetabulum was not associated with excessive rates of wound-healing complications, but the incidence of heterotopic ossification was increased.

Anterior pelvic external fixation: is there an optimal placement for the supra-acetabular pin?

Anterior pelvic external fixation using supra-acetabular bone pins is frequently used for manipulation and reduction of unstable pelvic ring injuries prior to definitive fixation. The supra-acetabular bone pin must be strategically placed in order to provide optimal frame stability, patient comfort, and hip mobility, without obstructing subsequent osseous fixation pathways. We describe a technique for alternative placement of supra-acetabular bone pins. The intraoperative imaging is detailed. The bone pin starting point is located more cranially at the anterior inferior iliac spine than previously described and the pin is directed to accommodate better hip motion.

Oblique distraction external pelvic fixation.

Simple anterior pelvic external fixation is a safe and effective strategy for reduction of pelvic ring deformity as well as the provisional or definitive stabilization of selected patterns of pelvic ring disruption. A two-pin oblique anterior pelvic deformity correction frame is a unique frame configuration designed to reduce and stabilize lateral compression pelvic ring disruptions associated with flexion/internal rotation hemipelvic deformities. In a small case series, we demonstrate that the oblique distraction external fixation frame alone or in combination with internal fixation is a simple and safe strategy for reduction and stabilization of unstable multiplanar hemipelvic deformities associated with partial posterior ring stability.

Iliosacral screw placement: are uniplanar changes realistic based on standard fluoroscopic imaging?

BACKGROUND: With the aim of improving the understanding of iliosacral screw placement, two hypotheses were tested: (1) standard intraoperative inlet and outlet images are not based on orthogonal coordinates, and (2) therefore making starting point and aim changes by moving perpendicular to the c-arm beam will displace the guide wire on the other intraoperative radiographic view. METHODS: This is a prospective case series with review of intraoperative data from consecutive patients treated at a University Level I trauma center. The study group included ten consecutive patients with nondysmorphic upper sacral segments and unstable posterior pelvic ring injuries that required surgical treatment. Posterior surgical stabilization included iliosacral screw placement using a standardized three- view technique in the supine position. The main outcome measurement included the angles from the perpendicular required to achieve what have been considered the ideal inlet and outlet views intraoperatively. The angle arc for each patient created by the recorded angles was then determined. RESULTS: The average sagittal plane tilt required to achieve the ideal inlet view was 25 degrees (range, 21-33 degrees). The average sagittal plane tilt required to achieve the ideal outlet view was 42 degrees (range, 30-50 degrees). The average arc between the ideal inlet and outlet views was 67 degrees (range, 62-76 degrees). These views never created an orthogonal system. CONCLUSION: We commonly work in orthogonal systems. Within these systems, it is possible to make a uniplanar correction by moving perpendicular to one plane or radiographic view. The ideal views to image the safe zone for iliosacral screw placement do not create an orthogonal system. When this average angle arc is placed on a graphic model of the pelvis, it becomes clear that the plane of the radiographic beam of the ideal inlet view is collinear with the anterior aspect of the upper two sacral bodies. The outlet view is oblique to the upper sacral bodies. Surgeons must keep this in mind when using fluoroscopic views to insert iliosacral screws.

Transiliac-transsacral screws for posterior pelvic stabilization.

Typical posterior pelvic fixation constructs use one or more large screws inserted from the lateral iliac cortex into the safe upper sacral ala or body. As a result of the deforming forces acting perpendicular to the implant axis, routine iliosacral screw fixation may not provide adequate stabilization, especially in certain unstable injuries. Longer iliosacral screws that traverse the entire upper sacrum and exit the contralateral iliac cortex may improve holding power and also stabilize concomitant contralateral posterior pelvic injuries. These transiliac-transsacral screws are reliably safe to insert using routine intraoperative fluoroscopy, and they provide durable fixation. These screws require careful preoperative planning and more precise technical attention during insertion because they pass through both sacral alar zones. Transiliac-transsacral screws may be particularly useful in the presence of osteoporosis, significant posterior pelvic instability including spinopelvic dissociation, patient obesity, anticipated noncompliant behavior, bilateral posterior pelvic injuries, and nonunion procedures.

The antishock iliosacral screw.

Acute traumatic pelvic ring injuries are associated with life-threatening hemorrhage related to pelvic instability. Rapid and effective methods to mechanically stabilize the pelvic injury are often a prerequisite for patient survival. Most of these methods have significant disadvantages because of either difficult application or limited efficacy. Pelvic antishock clamp placement is difficult and dangerous, and circumferential pelvic antishock sheeting is not universally effective in reducing and stabilizing the pelvic ring. We describe a technique of acute posterior pelvic ring reduction and stabilization using a percutaneously inserted iliosacral screw as a resuscitation adjunct.

Radiographic quantification and analysis of dysmorphic upper sacral osseous anatomy and associated iliosacral screw insertions.

OBJECTIVE: To quantify upper sacral dysmorphic osseous anatomy and assess its impact on second sacral segment iliosacral screw insertion. DESIGN: Retrospective evaluation of a prospective trauma database. SETTING: Regional Level I trauma center. PATIENTS: Twenty-four patients with unstable posterior pelvic ring disruptions and sacral dysmorphism were evaluated radiographically and second segment (S2) screws were placed using a standard technique. MAIN OUTCOME MEASUREMENTS: The sacral osseous pathway limits were measured using preoperative pelvic computed tomography at the upper and second sacral segments. The S2 screw location relative to the sacral nerve root tunnels and the maximum possible screw lengths for both S1 and S2 screws were evaluated with postoperative pelvic computed tomography. The S2 screw positions were graded as intraosseous, juxtaforaminal, or extruded. Preoperative and postoperative peripheral neurologic examinations were documented. RESULTS: The dysmorphic S1 width available for screw insertion averaged 13.2 mm. The S2 pathway width averaged 15.2 mm. The maximum potential screw length for the dysmorphic S1 averaged 100.8 mm and for S2 measured 151.9 mm. Twenty of 24 patients with S2 screws were intraosseous and in four patients were juxtaforaminal. There were no extruded screws. There were no neurologic injuries. CONCLUSIONS: Dysmorphic S1 segments are anatomically competent for routine screw fixation. The S2 segment provides a larger osseous site for screw insertion than S1 in dysmorphic sacrums. Significantly longer screws are possible in S2 compared with the dysmorphic S1 segment. S2 iliosacral screws can be safely and accurately accomplished using a standard technique in patients with unstable posterior pelvic ring disruptions and sacral dysmorphism. Safe screw insertions avoid iatrogenic nerve root injuries.

Direct hip joint distraction during acetabular fracture surgery using the AO universal manipulator.

Certain acetabular fractures may necessitate distraction of the hip joint for removal of intra-articular debris and assessment of reduction. Distraction can be accomplished by manual traction, using a traction table or an AO universal manipulator (UM). The UM is a relatively simple and an inexpensive device that can provide focal distraction in a controlled manner without the risks associated with the use of a traction table. We describe a technique using the UM for hip joint distraction during acetabular fracture surgery through a Kocher-Langenbeck surgical exposure.

The impact of open reduction internal fixation on acute pain management in unstable pelvic ring injuries.

BACKGROUND: The management of unstable pelvic ring injuries is complex. Displacement is a clear indication for surgical intervention. However, reduction of acute pain after stabilization may have substantial clinical benefits and affect management decisions. The purpose of this study was to determine the impact of operative fixation of unstable pelvic ring injuries in diminishing acute pain. METHODS: During a 33-month period, 70 patients with isolated pelvic ring injuries were managed at a Level-1 trauma center and retrospectively reviewed. On the basis of clinical and radiographic instability, 38 patients were managed surgically and formed the study group. Pain was assessed using visual analog scales and narcotic consumption during the index hospitalization. RESULTS: In the operative group, visual analog scale scores decreased 48% after fixation from 4.71 +/- 1.8 preoperatively to 2.85 +/- 0.8 postoperatively (p < 0.001). Concomitantly, narcotic requirements decreased 25% from 2.26 mg morphine per hour preoperatively to 1.71 mg morphine per hour postoperatively (p = 0.024). The mean total length of hospital stay was 5.6 days (SD, 1.2 days), and the postoperative length of hospital stay was 4.7 days (SD, 1.2 days). CONCLUSIONS: Operative reduction and fixation of unstable pelvic ring injuries significantly decreases acute pain. This has substantial physiologic benefits, particularly by improving mobilization, and should be an additional factor when determining surgical indication and timing.

The upper sacral nerve root tunnel: an anatomic and clinical study.

OBJECTIVES: To radiographically demonstrate the upper sacral nerve root tunnel (USNRT) in both cadaveric specimens and a clinical cohort and to quantify its clinical relevance. SETTING: Level 1 trauma center and anatomy laboratory. PATIENTS AND PARTICIPANTS: Eleven cadaveric pelves and 23 consecutive patients who underwent fluoroscopically assisted iliosacral screw insertions. INTERVENTIONS: Cadaveric pelves were fluoroscopically imaged using standard pelvic inlet, outlet, and true lateral sacral views. The course of the USNRT pathway was identified. Then, these tunnels were filled completely with a semisolid radio-opaque agent. The specimens were reimaged after the contrast injection. Clinically, 23 consecutive patients with unstable posterior pelvic ring disruptions were treated using fluoroscopically assisted percutaneous iliosacral screws based on these predictable radiographic landmarks. A total of 44 iliosacral screws were inserted. MAIN OUTCOME MEASUREMENTS: For the cadaveric portion, the images with contrast were used to identify the USNRTs. For the clinical study, tunnel visualization was determined on all views intraoperatively. Screw placement was documented by postoperative pelvic plain radiographs and computed tomography scan. RESULTS: In the cadaveric specimens, the contrast agent consistently demonstrated the USNRTs on all 3 pelvic radiographic views. In the clinical series, the USNRTs were well visualized on the pelvic outlet image in all 23 patients (100%). Using the inlet image, the USNRTs were visualized in only 5 of 23 patients (21%). On the true lateral sacral views, the USNRTs were seen in 21 of 23 patients (91%). Using these USNRT radiographic landmarks, no iliosacral screw was extraosseous. CONCLUSIONS: The USNRTs have a consistent radiographic appearance that is best seen on the pelvic outlet and true lateral sacral views, but their course is best understood when seen on all 3 views. Awareness and understanding of the USNRT, its course, and its radiographic landmarks allow the surgeon to avoid tunnel intrusion by an iliosacral screw.

Internal rotation and taping of the lower extremities for closed pelvic reduction.

External rotation of the disrupted hemipelvis is a common deformity after pelvic ring trauma, especially in anteroposterior compression injury patterns. This displacement is associated with significant pelvic hemorrhage. Emergent closed reduction techniques are necessary to diminish the potential pelvic volume, provide temporary stability, and allow tamponade with clot formation. Circumferential pelvic antishock sheeting is effective but may be cumbersome, especially in patients with truncal obesity. In such scenarios, circumferential pelvic area sheeting does not always achieve a complete reduction. We present a technique of internal rotation and taping of the lower extremities as an alternative or supplemental pelvic closed reduction method.

Percutaneous placement of iliosacral screws without electrodiagnostic monitoring.

BACKGROUND: Iliosacral screws are commonly used for fixation of pelvic ring injuries. Previous reports using different screw insertion techniques have reported high neurologic complication rates, leading to recommendations for intraoperative neurodiagnostic monitoring. The purpose of this study was to evaluate the neurologic complications after percutaneous iliosacral screw placement without neurodiagnostic monitoring. METHODS: During a 21-month period, 326 patients with pelvic ring disruptions were treated at a level 1 trauma center. One hundred seventy-four patients underwent percutaneous stabilization of their pelvic ring injuries without neurodiagnostic monitoring. Patients who were not intubated preoperatively, were neurologically normal, and who underwent a closed reduction were included. Sixty-eight patients who had 106 screws placed met the inclusion criteria and formed the study group. A careful and detailed neurologic examination was performed preoperatively and postoperatively. Plain pelvic radiographs and computed tomography scans were evaluated postoperatively in all patients to assess screw position. RESULTS: No planned screw placement was abandoned because of inadequate fluoroscopic visualization. There were no neurologic injuries as a result of either the closed reduction or the screw placement. Computed tomography scans confirmed the screw position and demonstrated placement as intraosseous in 75 (70.8%) and juxtaforaminal in 31 (29.2%). No screws perforated a nerve root tunnel, spinal canal, or sacral cortex. CONCLUSIONS: Using a standardized technique, appropriate and reliable fluoroscopic landmarks are available in the vast majority of percutaneous iliosacral screw fixation procedures. Iliosacral screw placement without neurodiagnostic monitoring has a low rate of neurologic complications.

Irreducible fracture-dislocations of the femoral head without posterior wall acetabular fractures.

OBJECTIVE: To define the unique clinical and radiographic features, operative treatment, and complications of irreducible femoral head fracture-dislocation without associated posterior wall fracture. DESIGN: Retrospective clinical study from a prospectively gathered trauma database. SETTING: Level I trauma center. PATIENTS/PARTICIPANTS: During a 6-year period (from January 2000 until August 2006), 72 patients with fractures of the femoral head (OTA 31C) were treated at a level I trauma center. Seven (9.7%) patients had irreducible femoral head fracture-dislocations without associated posterior wall acetabular fractures and underwent operative management. INTERVENTION: Open reduction and internal fixation of the irreducible femoral head fracture-dislocation with miniature fragment screw fixation using a Smith-Petersen exposure. MAIN OUTCOME MEASURES: Clinical and radiographic markers of irreducibility, surgical findings, fixation methods, reduction accuracy, and injury- and treatment-related complications. RESULTS: Standardized postoperative pelvic computed tomography scans revealed that all 7 femoral head fractures were accurately reduced. Two patients with delayed operative management developed femoral head aseptic necrosis and underwent hip arthroplasty. CONCLUSIONS: Irreducible femoral head fracture-dislocations without associated posterior wall fractures occur rarely, but are heralded by unique clinical and radiographic features. These patients warrant special consideration in terms of recognition and management. The physical examination findings and specific radiographic markers should alert the surgeon to this injury pattern and its related complications. Closed reduction of this fracture-dislocation should not be attempted. Delayed operative management may be related to femoral head aseptic necrosis. Accurate reduction and stable fixation can successfully be performed through a Smith-Petersen surgical exposure using small or miniature fragment cortical screws alone.

Open reduction of intracapsular hip fractures using a modified Smith-Petersen surgical exposure.

The Smith-Petersen or modified direct anterior hip surgical exposures have not previously been described for open reduction of femoral neck fractures. This technique of reduction provides a direct approach to the femoral neck and hip joint. Displaced fractures of the femoral neck can easily be reduced through this approach, local osseus defects resulting from impaction can be supported with bone graft, and fracture fixation is then placed through a separate lateral exposure or through small stab incisions. The technique of reduction is presented.