Anterior Pelvic External Fixation Research Articles

Supra-acetabular Pin Placement Without Fluoroscopy in Anterior Pelvic External Fixation Application

High-energy pelvic ring injuries are associated with a significant rate of mortality and may require urgent stabilization with anterior pelvic external fixation. The iliac crest can be used for pin placement, but supra-acetabular pin placement is biomechanically superior. Traditionally, supra-acetabular pin placement is performed in the operating room, with time-consuming imaging techniques. However, because of the implicit high-energy nature of these injuries, patient physiology may prevent transport to the operating room and preclude the use of tedious image-guided techniques. Here, we describe a technique that can be performed at the bedside and without image guidance. [Orthopedics. 20XX;XX(X):xx-xx.].

Finite element analysis of anterior ring injuries in unstable pelvic fractures treated by different methods

To compare the biomechanical stability of different fixation methods for anterior ring injury of unstable pelvic fractures, and to provide reference for clinical treatment. An unstable pelvic fracture model (Tile C) with one side of the sacroiliac joint dislocation and the pubic rami fracture was constructed via three-dimensional finite element analysis. Five different fixation methods were used in the front, and the rear was fixed with sacroiliac screws. The von Mises stress and strain distributions of different combinations of fixation methods were analyzed under mimicking standing conditions. After being loaded with 500 N vertically, the maximum stress in the anterior fracture was 3.56 MPa in anterior pelvic external fixation (AEF) group, the total displacement and the vertical displacement of the Y axis at the sacroiliac joint and the fracture were not more than 1.5 mm. The maximum stress at fixation, the front of the fracture and sacroiliac joints in the anterior pelvic subcutaneous approach(APA) group and AEF, was significantly higher than anterior modified Stoppa approach(ASA) group, anterior pelvic Ilioinguinal approach (AIA) group, and canulated screw fixation(CSF) group. The total displacement and the vertical displacement of the Y axis at the sacroiliac joint and the fracture in APA group and AEF group were also greater than the other three groups. Anterior ring injury of unstable pelvic fractures can be significantly improved after the fixation of the implants in the five combined methods. However, overall biomechanical properties of ASA, AIA and CSF group are superior to APA and AEF group.

Occult injuries of the contralateral sacroiliac joint in operatively treated pelvis fractures: incidence, root cause analysis, and proposal of treatment algorithm.

To determine the most common injury patterns, root cause, and the frequency with which unrecognized contralateral posterior ring injury occurs in patients presenting with surgically treated pelvic fractures. The medical records of 73 patients presenting to our level I trauma center (52 male and 21 female patients; mean age 41.8years; range 18-89years) with surgically treated pelvic ring fractures between January 1, 2016 and January 1, 2018 were reviewed. Patient demographics, mechanism of injury, associated injuries, imaging prior to binder or external fixation, use of temporary stabilization with pre-peritoneal pelvic packing (PPP) and anterior pelvic external fixation, and fracture pattern were recorded and analyzed to identify independent risk factors contributing to occult contralateral missed posterior ring injury. Occult contralateral pelvic ring injuries occurred in 6/72 patients (8.2% incidence). Pelvis fractures in multiply traumatized patients with associated orthopaedic injuries were associated with higher prevalence of occult contralateral pelvic ring injury (relative risk 1.85, 95% CI 1.13-3.02) as compared to patients with isolated pelvic fractures. There is an 8.2% incidence of unrecognized contralateral SI joint instability in patients presenting with unstable pelvic ring injuries. Multiply traumatized patients with multiple orthopaedic injuries were an independent risk factor for this injury pattern.

A biomechanical study comparing minimally invasive anterior pelvic ring fixation techniques to external fixation

IntroductionINFIX and Pelvic Bridge are two new minimally invasive surgical techniques for unstable pelvic ring injuries, and they have demonstrated early clinical success in small, single-center case-series. The primary objective of this study is to gather evidence speaking to the biomechanical stability of internal bridging methods relative to external fixation, with the expectation of biomechanical equivalence. MethodsTen human cadaveric pelvic specimens were dissected free of all skin, fat, organs, and musculature and were prepared with a partially unstable pelvic ring injury (OTA/AO 61-B). The specimens were randomized to two groups and were repaired and tested with anterior pelvic external fixation (APEF) and INFIX sequentially, or APEF and Pelvic Bridge sequentially. Testing was performed with each specimen mounted onto a servo-hydraulic testing frame with axial compression applied to the superior base of the sacrum under five axial loading/unloading sinusoidal cycles between 10 N and 1000 N at 0.1 Hz. Relative translational motion and rotation across the osteotomy site was reported as our primary outcome measures. Outcome measures were further analyzed using a Wilcoxon signed-rank test to determine differences between non-parametric data sets with significance defined as a p value < 0.05. ResultsWe found no statistical difference in translation (p = 0.237, 0.228) or rotation (p = 0.278, 0.873) at the fracture site when comparing both new constructs to external fixation. Under the imposed loading protocol, no episodes of implant failure or failure at the bone-implant interface occurred. DiscussionOur study provides the biomechanical foundation necessary to support future clinical trial implementation for pelvic fracture patients. While biomechanical stability of these newer, subcutaneous techniques is equivalent to APEF, the surgeon must take into account their technical abilities and knowledge of pelvic anatomy, patient-specific factors including body habitus, and the potential complications associated with each implant and the ability to avoid them.

Modified pedicle screw-rod fixation versus anterior pelvic external fixation for the management of anterior pelvic ring fractures: a comparative study

BackgroundAnterior pelvic ring fracture, as high-energy trauma, needs to be effectively treated. The purpose of the current study was to evaluate the clinical applications of modified pedicle screw-rod fixation and anterior pelvic external fixation for the treatment of anterior pelvic ring fracture.MethodsEither modified pedicle screw-rod fixation (modified PSRF group, N = 21) or anterior pelvic external fixation (APEF group, N = 22) was performed to 43 patients, with or without fixation of posterior ring. Clinical outcomes were evaluated via Majeed scores. Relevant clinical evaluation indicators including operation time, intraoperative blood loss, hospitalization duration, and complications were compared between these two groups.ResultsThe operation time in APEF group was significantly less than that in modified PSRF group (P < 0.0001). No significant difference with respect to intraoperative blood loss and hospitalization duration between the two groups was shown (P = 0.51 and P = 0.33, respectively). Six patients developed surgical site infection in APEF group. Three patients experienced loss of fixation, and two patients experienced loosening of fixator in APEF group. Temporary lateral femoral cutaneous nerve irritation occurred in three patients in modified PSRF group while two patients in APEF group. One patient experienced femoral nerve palsy in modified PSRF group. Fractures of all patients healed well eventually. No statistical difference regarding Majeed evaluation scores was found between two groups.ConclusionsApplication of both modified PSRF and APEF could provide similar satisfactory clinical outcomes for anterior pelvic ring fracture. Modified PSRF, a minimally invasive technique with the advantages of internal fixation, could be performed as an alternative method for instable pelvic fractures.Trial registrationResearch Registry UIN: researchregistry2776.

Midterm radiologic and functional outcomes of minimally-invasive fixation of unstable pelvic fractures using anterior internal fixator(INFIX) and percutaneous iliosacral screws.

Anterior pelvic external fixation is associated with pin site infections, aseptic loosening with loss of reduction, frame bulkiness hindering patient mobilization and consequent difficulties in inpatient nursing. We performed a single-center prospective series to evaluate the feasibility, safety, limitations and midterm radiologic and functional outcomes of an alternative minimally invasive pelvic internal fixation technique using an anterior subcutaneous pelvic internal fixator (INFIX) and percutaneous iliosacral screws in unstable pelvic ring fractures. Fifteen consecutive patients with vertically and/or rotationally unstable pelvic fractures, presenting to a Level-1 trauma center were treated with closed reduction, appropriate posterior stabilization with percutaneous iliosacral screws and anterior INFIX application. Outcomes were analyzed with respect to the quality of fracture reduction (Matta's radiologic criteria), ease of inpatient nursing, patient mobility and comfort, functional outcomes at final follow-up (Majeed score, SF-12 score), social reintegration and complications. Most common injury pattern was AO/OTA type 61-C pelvic fracture in thirteen patients. Mean procedure time and intra-operative blood loss were, 57.1+/-4.9min (range,51-68min) and 115.3+/-26.7ml (range,80-170ml) respectively. Mean follow-up was 34.9+/-4.1 months (range,31-42 months). Fracture reduction was excellent in twelve and good in three patients (Matta's criteria). Functional outcomes were excellent in eight and good in seven patients (Majeed score). Mean SF-12 scores for physical and mental health were 48.58+/-5.61 and 50.89+/-3.97 respectively. Thirteen patients returned to their pre-injury jobs. All fifteen patients reintegrated into society without any restrictions. INFIX was removed at a mean post-operative period of 7.3+/-1.5 months (range,5.5-11 months). Complications included, lateral femoral cutaneous nerve irritation(n=1), superficial wound infection(n=1) and loss of reduction(n=2). Minimally invasive pelvic stabilization using INFIX and percutaneous iliosacral screws is easy to learn and apply, achieves good fracture reduction and definitive stabilization with minimum complications and offers excellent functional outcomes at a minimum follow-up of 31 months. Level IV.

Minimal Invasive Surgical Treatment of Fragility Fractures of the Pelvis.

The incidence of fragility fractures of the pelvis is increasing quickly. The characteristics of these fractures are different from pelvic ring disruptions in adults. Fragility fractures of the pelvis are the consequence of a low-energy trauma which occurs in a patient with an important decrease of bone mineral density. Due to a consistent pattern of alteration of bone mass distribution in the sacrum, other fracture morphologies occur than in younger adults. The leading symptom is immobilizing pain in the lower back, in the buttocks, in the inguinal region and/or at the pubic symphysis. Conventional radiographs and CT will show the presence and localization of the fractures in the anterior and posterior pelvic ring. A new, comprehensive classification system distinguishes four categories of instability. This first criterion is most important, because it also gives hints for the preferred type of treatment. The second criterion, leading to the subtypes in the four categories, is the localization of the instability in the posterior pelvic ring. This criterion points the way towards the type of the surgical procedure to be used. When a surgical treatment is chosen, the procedure should be as minimal invasive as possible. Different techniques for percutaneous or less invasive fixation of the posterior pelvic ring have been developed. Their advantages and limitations are presented: sacroplasty, iliosacral screw osteosynthesis, cement augmentation, transiliac internal fixation, trans-sacral osteosynthesis, lumbopelvic fixation. Fractures of the anterior pelvic ring also need special attention. Retrograde transpubic screw fixation is recommended for pubic rami fractures. Fractures of the pubic body and instabilities of the pubic symphysis need bridging plate osteosynthesis. We do not recommend anterior pelvic external fixation in elderly because of the risk of pin track infection and pin loosening.

Treatment of Vertically Unstable Sacral Fractures with Pelvic External Fixation and Skeletal Traction

Objective: To determine the efficacy in treatment of vertically unstable sacral fractures with pelvic external fixation and skeletal traction. Patients and Methods: The pelvic external fixation and skeletal traction were applied on 12 cases of vertically unstable sacral fracture (eight males and four females, at age of 19 - 52 years, mean 35.2 years) including two cases of Denis Zone I, nine of Zone II, and one of Zone III. All patients were treated with the pelvic external fixation, and pre- and post-operational longitudinal skeletal traction. Results: The mean operation time, skeletal traction time, skeletal traction removal time and full weight bearing time were 38 min, 4.5 weeks, 8.5 weeks, and 10.3 weeks respectively. All these patients were followed up for 12 - 36 months (average, 22.5 months), which showed no associated complication. The function results were rated as excellent in four cases, good in six and fair in two, with a mean score of 84.4 points, according to Majeed scoring system. Conclusion: The anterior pelvic external fixation with continuous skeletal traction can reliably restore and stabilize the vertically unstable sacrum fracture with excellent functional and radiographic outcomes. It is an ideal method to treat unstably vertical sacral fracture.

Anterior Pelvic External Fixator Versus Subcutaneous Internal Fixator in the Treatment of Anterior Ring Pelvic Fractures

To compare the short-term results of anterior pelvic external fixation (APEF) versus anterior pelvic internal fixation (APIF) applied subcutaneously in the context of surgical treatment of pelvic ring injuries. A single center retrospective chart review. A level 1 trauma center. A consecutive series of 48 patients who underwent surgical stabilization of their anterior pelvic ring (24 utilizing APIF and 24 utilizing APEF) by 2 surgeons at a single hospital were studied. The choice to use either APEF or APIF was left up to each surgeon, the indications for use are the same. Data collected included surgical or postoperative complications including infection, implant failure, reoperation, documented surgical site pain persisting to clinical follow-up visits, and radiographic union. Measurements on inlet and outlet pelvic radiographs were made immediately postoperation and at all follow-up clinic visits to determine whether there were differences in maintaining pelvic fracture reduction. Statistical analysis was performed to evaluate significant differences between the 2 groups with regard to each of these variables. The APIF group was found to have a significantly lower incidence of wound complication (P < 0.05) and a lower occurrence of associated morbidity events as compared with the APEF group. In addition, the APIF group was found to have a significantly lower rate of surgical site pain persisting through all clinical follow-up intervals (P = 0.05). There was no difference between the 2 groups in terms of maintenance of pelvic reduction in the early postoperative phase or at final follow-up. No other significant differences were observed between the 2 groups. The present study, which was based on our initial experience with the subcutaneous anterior pelvic fixator, demonstrated encouraging clinical outcomes in terms of a lower wound complication rate and associated morbidity, and surgical site symptoms, although maintaining equivalent reduction. These findings suggest that further analysis of this technique is warranted to determine if it can be definitively recommended for general use. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

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.

Anterior Pelvic Reduction and Fixation Using a Subcutaneous Internal Fixator

Acute traumatic pelvic instability mandates reduction and mechanical stabilization to maximize the chance of a good functional outcome. Posterior pelvic fixation is frequently inadequate to stabilize the pelvic ring in isolation. Fixation augmentation with anterior pelvic ring implants can take several forms, including plates, medullary screws, or external fixation. Based on a multitude of patient and injury factors, external fixation may be the definitive anterior pelvic implant of choice. However, many drawbacks exist with this treatment, most notably the high infection rates of the transcutaneous pins, impaired patient mobilization, and suboptimal mechanical properties. We present a technique of a subcutaneous anterior pelvic fixator as an alternative method of anterior pelvic ring reduction and stabilization that avoids many of the drawbacks of traditional anterior pelvic external fixation.

Surgical Technique: A Percutaneous Method of Subcutaneous Fixation for the Anterior Pelvic Ring: The Pelvic Bridge

Management of pelvic ring injuries using minimally invasive techniques may be desirable if reduction and stability can be achieved. We present a new technique, the anterior pelvic bridge, which is a percutaneous method of fixing the anterior pelvis through limited incisions over the iliac crest(s) and pubic symphysis. An incision is made over each anterior iliac crest and a 6- to 8-cm incision is centered over the symphysis. Either a locking reconstruction plate or a spinal rod is placed through a subcutaneous tunnel overlying the external oblique fascia in the subcutaneous tissue, and fixation into the iliac crest and pubis is achieved to effect stability. A randomized controlled trial comparing anterior pelvic external fixation (APEF) versus anterior pelvic internal fixation (APIF) for unstable pelvic ring injuries was begun in October 2010. Patients with unstable pelvic ring injuries were enrolled and followed with respect to fracture reduction, surgical pain, complications, and functional outcome scores. As of January 2012, 23 patients met inclusion; however, 12 patients refused participation because of the possibility of external fixation, leaving 11 patients (four male, seven female) enrolled. At 6-month followup, there was a single pin tract infection in the APEF cohort and no complications or pain in the APIF cohort. This clinical experience lends support to the use of a new minimally invasive technique to stabilize the anterior pelvis, particularly given the resistance on the part of patients to consider external fixation. Level II, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Bladder incarceration following anterior external fixation of a traumatic pubic symphysis diastasis treated with immediate open reduction and internal fixation

Anterior pelvic ring disruptions are often associated with injuries to the genitourinary structures with the potential for considerable resultant morbidity. Herniation of the bladder into the symphyseal region after injury with subsequent entrapment upon reduction of the symphyseal diastasis has seldom been reported in the literature. We report such a case involving bladder herniation and subsequent entrapment after attempted closed reduction with anterior pelvic external fixation immediately treated with open reduction and internal fixation along with a review of the literature.

Clinical treatment of unstable pelvic fractures with AO external fixator

目的 探讨AO外固定架对不稳定性骨盆骨折治疗的疗效和经验.方法回顾性分析24例(13例结合内固定治疗)AO外固定架治疗不稳定性骨盆骨折患者,总结该治疗方法的经验及体会.结果除1例因腹腔脏器破裂大量失血在固定后1 d死于失血性休克外,其余23例平均随访13个月,按Matta评定标准,优良率达87.5%.结论①多数情况下单纯外固定架可改善骨盆的稳定性,也可作为终极治疗手段,必要时与内固定结合可增加骨盆的稳定性;②单纯外固定架固定可用于绝大多数B型及部分C型骨折的治疗;③对那些严重损伤,骨盆稳定性差,合并有其它脏器损伤患者,急诊期骨盆外固定架治疗效果显著。

Simple Anterior Pelvic External Fixation

Unstable pelvic ring disruptions are often associated with significant morbidity and mortality, especially in patients with multiple injuries. Early pelvic fixation provides stability and should diminish ongoing hemorrhage. A simple anterior single-pin pelvic external fixator can be applied rapidly and accurately to stabilize pelvic ring injuries as a part of the initial patient resuscitation of such patients. Simple anterior pelvic external fixation (SAPEF) frames can be used as either temporary, definitive, or supplementary fixation depending on the pelvic injury pattern. Over a 32-month period, 41 patients with unstable pelvic ring disruptions were stabilized using a simple anterior pelvic external fixator. Eight patients had open pelvic ring injuries and 13 others had genitourinary system disruptions. Fluoroscopic imaging was used to insert all of the fixation pins into the iliac crest between the iliac cortical tables to a depth of at least 5 cm. Each patient had closed manipulative reduction of the pelvic ring using external methods before SAPEF application. One patient died less than 24 hours after injury because of torrential hemorrhage. Clinical evaluations and serial radiographs, including postoperative computed tomographic scans, were available for the other 40 patients postoperatively. Seventy-five of the 80 (94%) pins were completely contained between the iliac cortical tables, according to the computed tomographic scans. The initial pelvic closed reductions were maintained until the fixators were removed in 37 of 40 patients (93%). Only one deep pin track infection developed, mandating early frame removal and intravenous antibiotic therapy. Simple anterior pelvic external fixation can be applied rapidly using fluoroscopic guidance to direct accurate pin insertion and closed manipulative reduction of the pelvis. Depending on the specific pelvic ring injury pattern and clinical scenario, SAPEF can serve as a resuscitative temporary fixation device, as definitive pelvic treatment, or as a supplement for pelvic internal fixation implants.

Percutaneous fixation of pelvic ring disruptions.

Percutaneous pelvic fixation is possible because intraoperative fluoroscopic imaging and other technologies have been refined. Anterior and posterior unstable pelvic ring disruptions are amenable to percutaneous fixation after closed manipulation or open reduction. Stable and safe fixation is achieved only after an accurate reduction. Anterior pelvic external fixation remains the most common form of percutaneous pelvic fixation; however, percutaneously inserted medullary pubic ramus, transiliac, and iliosacral screws stabilize pelvic disruptions directly while diminishing operative blood loss and operative time. These percutaneous techniques do not decompress the pelvic hematoma allowing early definitive fixation without the risk of additional hemorrhage. Complications associated with open posterior pelvic surgical procedures are similarly avoided by using percutaneous techniques. A thorough knowledge of pelvic osseous anatomy, injury patterns, deformities, and their fluoroscopic correlations are mandatory for percutaneous pelvic fixation to be effective.

Approach to the Polytraumatized Patient With Musculoskeletal Injuries

The management of the multiply injured patient is a challenge for even experienced clinicians. Because many community hospitals lack a dedicated trauma team, it is often the orthopaedic surgeon who will direct treatment. Therefore, the orthopaedic surgeon must have an understanding of established guidelines for the evaluation, resuscitation, and care of the severely injured patient. Initial evaluation encompasses assessment and intervention for airway, breathing, circulation, disability (neurologic injury), and environmental and exposure considerations. Resuscitation requires not only administration of fluids, blood, and blood products but also emergent management of pelvic trauma and stabilization of long-bone fractures. Judicious early use of anterior pelvic external fixation can be lifesaving in many cases. The secondary survey, which is often neglected, must incorporate a thorough physical evaluation. Although the method of fracture stabilization is still controversial, most clinicians agree that early fixation offers many benefits, including early mobilization, improved pulmonary toilet, decreased cardiovascular risk, and improved psychological well-being. Without an understanding of the complexities of the multiply injured patient, delays in the diagnosis and treatment of a patient's injuries are likely to adversely affect outcome.

Indications for anterior fixation of pelvic fractures.

From April 1982 to August 1995, the author treated 127 patients with pelvic ring injuries by open reduction and internal fixation within 3 weeks of injury. Fifty-five (43%) patients (none of whom had a symphysis dislocation) had posterior internal fixation without anterior pelvic internal or external fixation. In 37 patients (29%) anterior and posterior internal fixation was performed whereas 35 patients (28%) were treated by anterior internal fixation alone. Plates and screws were used for all anterior fixations. Bladder or urethral injury was not considered a contraindication to anterior internal fixation. Of 109 patients who were observed until union of their fractures, 3 required a repeat surgery because of loss of reduction or failure of fixation or both. All 3 patients maintained reduction and healed after the second intervention. Of 72 anterior internal fixations, 1 deep infection was the only surgical complication. A single plate is reliable for fixation of the symphysis pubis and when necessary, the superior pubic ramus. However, even in displaced and unstable pelvic ring injuries, most fractures of the pubic rami do not require stabilization by internal or external fixation. Eighty-eight of 105 fractures of the obturator ring were not internally fixed and none required subsequent treatment for nonunion or loss of reduction; nor did their initial instability cause failure of posterior fixation. Internal fixation of the anterior pelvic ring, though safe and reliable, should be reserved for symphysis pubis dislocations and only a minority of pubic ramus fractures.