Treatment of unstable pelvic ring injuries with an internal anterior fixator and posterior fixation: initial clinical series

Comparison of Biomechanical Performance of Five Different Treatment Approaches for Fixing Posterior Pelvic Ring Injury

Background

A large number of pelvic injuries are seriously unstable, with mortality rates reaching 19%. Approximately 60% of pelvic injuries are related to the posterior pelvic ring. However, the selection of a fixation method for a posterior pelvic ring injury remains a challenging problem for orthopedic surgeons. The aim of the present study is to investigate the biomechanical performance of five different fixation approaches for posterior pelvic ring injury and thus provide guidance on the choice of treatment approach in a clinical setting.

Methods

A finite element (FE) model, including the L3-L5 lumbar vertebrae, sacrum, and full pelvis, was created from CT images of a healthy adult. Tile B and Tile C types of pelvic fractures were created in the model. Five different fixation methods for fixing the posterior ring injury (PRI) were simulated: TA1 (conservative treatment), TA2 (S1 screw fixation), TA3 (S1 + S2 screw fixation), TA4 (plate fixation), and TA5 (modified triangular osteosynthesis). Based on the fixation status (fixed or nonfixed) of the anterior ring and the fixation method for PRI, 20 different FE models were created. An upright standing loading scenario was simulated, and the resultant displacements at the sacroiliac joint were compared between different models.

Results

When TA5 was applied, the resultant displacements at the sacroiliac joint were the smallest (1.5 mm, 1.6 mm, 1.6 mm, and 1.7 mm) for all the injury cases. The displacements induced by TA3 and TA2 were similar to those induced by TA5. TA4 led to larger displacements at the sacroiliac joint (2.3 mm, 2.4 mm, 4.8 mm, and 4.9 mm), and TA1 was the worst case (3.1 mm, 3.2 mm, 6.3 mm, and 6.5 mm).

Conclusions

The best internal fixation method for PRI is the triangular osteosynthesis approach (TA5), followed by S1 + S2 screw fixation (TA3), S1 screw fixation (TA2), and plate fixation (TA4).

Biomechanical comparison of minimally invasive treatment options for Type C unstable fractures of the pelvic ring

BACKGROUND

The definite treatment of pelvic C fractures presents a widely discussed issue and undergoes continuous evolution. While the stabilization of the posterior ring has been studied extensively, the fixation of the anterior pelvic ring continuous to be rarely investigated. The importance of the simultaneous stabilization however lays in the earlier mobilization and prevention of long-term damage to the pelvis. Therefore we investigated four combinations of minimally invasive fixation techniques for unstable type C1-3 pelvic injuries and aimed to answer the following research questions: (1) what combination of fixation methods yields the highest stiffness and the least displacement? (2) Is the combination of a single sacroiliac screw (SI-screw) with a transiliac internal fixator (TIFI) a reasonable alternative to two SI-screws? (3) Is a modified unilateral anterior fixation comparable to a retrograde transpubic screw?

HYPOTHESIS

Minimally invasive fixation techniques provide sufficient biomechanical stability for type C pelvic fractures.

METHODS

Thirty synthetic full pelvises were divided into 5 groups, of which 4 groups were assigned a different osteosynthesis method and one was an intact pelvis used as reference (group 1: internal fixator+2 sacroiliac screws, group 2: internal fixator+transiliac internal fixator+1 sacroiliac screw, group 3: retrograde transpubic screw+2 sacroiliac screws, group 4: retrograde transpubic screw+transiliac internal fixator+1 sacroiliac screw). The pelvises underwent a protocol of cyclic loading between 100N and 200N, during which they were subjected to compression loads while the position of the fracture fragments was measured every 30 milliseconds. Displacement and stiffness were calculated for statistical analysis.

RESULTS

The minimally invasive fixation methods investigated in this study all provide sufficient biomechanical stability without one method being superior to the others (p [anterior displacement]=0.61 and p [posterior displacement]=0.88). Group 3 was allowed the least displacement (1.8±0.2mm for anterior and posterior fracture) for the treatment of a C1.3 fracture. The other fixation methods displayed the following dislocations (mm) of the anterior pelvic ring: group 1: 1.9±0.3, group 2: 2.1±0.4, group 4: 2.0±0.5. Posteriorly, the displacements (mm) were the following: group 1: 1.8±0.6, group 2: 1.9±0.2, group 4: 2.0±0.5.

DISCUSSION

The minimally invasive fixation methods investigated in this study all provide sufficient biomechanical stability without one method being superior to the others since differences were not significant regarding anterior and posterior displacements. Even if not significantly, we could reveal that out of all the methods tested the combination of 2 SI-screws with a retrograde transpubic screw (group 3) displayed the least displacement and highest stiffness. These techniques could therefore potentially improve patient's clinical outcome by reducing the surgical invasiveness and procedure time while providing sufficient biomechanical stability.

LEVEL OF EVIDENCE

III, comparative in vitro study.

[Anterior subcutaneous internal fixation combined with posterior percutaneous iliosacral screw for treatment of unstable pelvic fractures]

OBJECTIVE

To assess the effectiveness of anterior subcutaneous internal fixation (INFIX) combined with posterior percutaneous iliosacral screw for the treatment of unstable pelvic fractures.

METHODS

Between August 2016 and November 2017, 19 cases of unstable pelvic fractures were treated with anterior subcutaneous INFIX combined with posterior percutaneous iliosacral screw. There were 14 males and 5 females, with an average age of 40.6 years (range, 17-69 years). Causes of injury included traffic accident injury in 11 cases, falling from height in 5 cases, bruise injury by heavy object in 3 cases. According to Tile classification, there were 2 cases of type B1, 6 cases of type B2, and 11 cases of type C. Anterior ring injuries included bilateral pubic ischial ramus fractures in 12 cases, unilateral pubic ischial ramus fractures in 5 cases, and symphysis pubis separation in 2 cases. Posterior ring injuries included sacroiliac ligament injuries in 2 cases, unilateral iliac bone fractures in 3 cases, unilateral sacral fractures in 11 cases, unilateral sacroiliac joint dislocation in 2 cases, and bilateral sacral fracture in 1 case. The intraoperative blood loss and operation time were recorded, and the fracture healing and postoperative complications were observed. Matta score was used to evaluate the reduction of fracture, and Majeed score was used to evaluate the postoperative function of patients.

RESULTS

The operation time was 47-123 minutes (mean, 61.4 minutes) and the intraoperative blood loss was 50-115 mL (mean, 61.1 mL). One case had superficial infection at the site of screw implantation, and 1 case had unilateral cutaneous nerve stimulation, which were cured after corresponding treatment. There was no damage of urinary system, reproductive system, and intestine. All cases were followed up 12-25 months (mean, 18.1 months). All the fractures healed after operation, the average healing time was 9.5 weeks (range, 8-13 weeks); no nonunion, delayed healing, internal fixation loosening, fracture, and other situations occurred. Of the 2 patients with lumbosacral plexus injury before operation, 1 recovered completely and 1 had residual mild claudication. At last follow-up, the reduction of fracture was evaluated by Matta scoring standard, the results were excellent in 13 cases and good in 6 cases, with an excellent and good rate of 100%; the function was evaluated by Majeed scoring standard, the results were excellent in 15 cases and good in 4 cases, with an excellent and good rate of 100%.

CONCLUSION

Minimally invasive pelvic stabilization by using anterior subcutaneous INFIX and posterior percutaneous iliosacral screw for treatment of unstable pelvic fractures, can achieve good fracture reduction and definitive stabilization with minimum complications and obtain excellent functional outcomes.

[Research progress in internal fixation for treatment of pelvic anterior ring injury]

Objective

To review the research progress of the application of internal fixation (INFIX) in the treatment of pelvic anterior ring injuries.

Methods

The recent literature about INFIX in the treatment of pelvic anterior ring injury concerning the surgery technique, biomechanical characteristics, indications, contraindications, advantages, complications, and effectiveness was extensively consulted, reviewed, and summarized.

Results

INFIX is a relatively novel technique for the treatment of pelvic anterior ring injuries at present. The advantages include good biomechanical properties, extensive indications, minimally invasion, convenient nursing, less complications, and excellent effectiveness.

Conclusion

It is a clinical method with obvious advantages and development potential for treatment of pelvic anterior ring injuries using INFIX, and further study is needed to improve its effectiveness.

Minimally Invasive Screw Fixation of Unstable Pelvic Fractures Using the "Blunt End" Kirschner Wire Technique Assisted by 3D Printed External Template

Objective

This study aimed to determine the accuracy and safety of the “blunt end” Kirschner wire (KW) technique for the minimally invasive treatment of unstable pelvic fractures with the assistance of a 3D printed external template.

Methods

Clinical data of 28 patients with unstable pelvic fractures between January 2016 and January 2018 were retrospectively analyzed. There were 6 cases of B1, 10 of B2, 8 of C1, and 4 of C2 fractures, all of which received surgical treatment. The “blunt end” KW technique with a 3D template was adopted for the minimally invasive placement of the iliosacral (IS) or superior ramus screws. The number of intraoperative fluoroscopies, surgical time, and complications were recorded. Postoperative reduction was assessed using the Matta criteria, and the Majeed score system was used to evaluate postoperative functional recovery.

Results

The average number of fluoroscopies was 35 per patient, and the average surgical time was 85.2 min. A total of 19 S1 and 28 S2 IS screws were inserted. Eleven antegrade superior ramus screws and 4 retrograde screws were placed in 11 patients, and anterior subcutaneous internal fixation (INFIX) was used to fix the anterior pelvic ring in 17 patients. All patients were followed up for an average of 18 months. Postoperative reduction was evaluated by Matta's criteria: excellent in 16 cases, good in 9 cases, and fair in 3 cases. The Majeed score was used in the last follow-up to evaluate functional recovery: excellent in 13 cases, good in 10 cases, fair in 4 cases, and poor in 1 case. There were no cases of operative vascular injury.

Conclusion

The “blunt end” KW technique with a 3D printed external template is a safe and effective method for the placement of IS and superior ramus screws in unstable pelvic fractures with minimized surgical duration and radiation exposure.

The Anterior Subcutaneous Pelvic Ring Fixator: No Biomechanical Advantages Compared with External Fixation

BACKGROUND

Subcutaneous fixation of the anterior pelvic ring is an emerging surgical technique for trauma patients. The aim of this study was to biomechanically evaluate 2 internal fixation devices for stabilizing a disrupted pelvic ring and compare them with traditional external fixation.

METHODS

Thirty-six synthetic pelvises with a simulated unstable ring fracture (anteroposterior compression type III) were divided into 3 groups. Group A underwent fixation with a supra-acetabular external fixator; group B, with an internal fixator using the USS II polyaxial system; and group C, with an internal fixator using the Click'X polyaxial system. Biomechanical testing included measurement of peak-to-peak displacement at 300, 400, and 500 N; total displacement; plastic deformation; stiffness; and fracture-line displacement.

RESULTS

Statistical analysis of all measured parameters revealed no significant differences among the groups. However, vertical displacement of the preshaped connecting rod within the screw heads occurred as a result of inadequate stability of the internal fixation at the rod-screw interface.

CONCLUSIONS

Although internal fixator devices are placed close to the bone and should therefore maintain greater stiffness, our data did not support the hypothesis of superior stability. Special attention is required when using a curved connecting rod as the rod is easily displaced, placing relevant anatomical structures at risk. These devices require further refinement to avoid potential patient injury.

Fixation of Anterior Pelvic Ring Injuries

Treatment of anterior pelvic ring injuries involves both acute stabilization during the initial resuscitation and definitive fixation. Definitive management has evolved substantially over the past 40 years with improved patient mobilization and long-term outcomes. Although its use has recently declined, external fixation remains a favorable option in certain situations. Symphyseal plating is the preferred technique for stabilization of symphyseal diastasis because of superior stability and low morbidity. Ramus screws can be effective for simple ramus fractures but require a careful technique because of the proximity of neurovascular structures. The subcutaneous internal fixator provides a good option for obese patients in whom external fixation would be poorly tolerated. Regardless of fixation strategy, posterior ring reduction and stabilization is crucial.

Complex Open Pelvic Fracture in an 8-Year-Old Girl Treated With INFIX-A Case Study

We describe the case of an 8-year old female patient with an open pelvic fracture after being run over by a bus. Open pelvic injuries in pediatric patients are very rare and are associated with high mortality rates and long-term morbidity. In this case, a multidisciplinary surgical approach is described. The injuries include a complex pelvic ring fracture, which was treated with an internal external fixator, together with severe urogenital and soft-tissue injury. The internal external fixator, a surgical technique involving a temporary internal fixation device, is well described in adults, but has not been described in pediatric patients before. This case presentation shows the severity and complexity of the treatment of open pelvic fractures with severe associated injures. Albeit the treatment of her orthopaedic injuries has been successful so far, our patient unfortunately still suffers notable morbidity from her other injuries.

INFIX/EXFIX: Innovation managing pelvic fractures in difficult scenarios

Pelvic fractures complicated by the presence of visceral injuries, open fractures and urethral or bladder injuries pose a significant challenge to treat. In these conditions internal fixation is usually contraindicated. External fixators, though a potential solution, have disadvantages like loss of reduction, pin tract infection and loosening. INFIX, a novel technique has been effective in managing anterior ring fractures and can be used as a substitute for internal fixation. We describe use of INFIX as EXFIX in three case scenarios where passing INFIX rod internally was precluded with favorable outcomes.

The use of anterior subcutaneous internal fixation (INFIX) for treatment of pelvic ring injuries in major trauma patients, complications and outcomes

Purpose: Pelvic anterior internal fixators (INFIX) are a relatively new alternative in the treatment of unstable pelvic fractures. The authors wanted to review the use of complications and outcomes of this method of pelvic fixation at our institution.

Method: Patients over the age of 18 who had an INFIX used in treatment of their pelvic ring injury were identified. Patient demographics, fracture type, injury severity score, morbidity, complications and time until removal were recorded. All available patients were followed up following the removal of the INFIX and completed an Iowa Pelvic Score (IPS) at this time.

Results and Discussion: 24 patients (19 male) with a mean age of 38.5 (range 18–71) met the inclusion criteria with an average injury severity score of 29.8 (10–66). The most common complication following insertion was a lateral femoral cutaneous nerve (LFCN) injury, which occurred in 11 patients (bilaterally in two), 6 patients (25%) had ongoing numbness 6 months post removal. Two patients had an infection, one of which prompted the removal of the INFIX. One INFIX was removed for implant failure. All other removals were planned electively. Heterotopic ossification was noted to have occurred in five cases. The mean IPS following removal of the INFIX was 79.2 (52–100). INFIX is a safe and successful treatment for unstable pelvic ring injuries. Overall, patients tolerate the INFIX well with good outcome scores. The main concern being the high rate of LFCN injuries, although many resolved after removal of the INFIX.

Modified internal fixator for anterior pelvic ring fractures versus conventional two-screw fixation

PURPOSE

The present study aims to evaluate the short-term clinical effects and complications of modified three-screw fixation and conventional two-screw fixation for treating anterior pelvic ring fractures.

METHODS

A retrospective study of 51 patients with type B fractures was performed. 25 patients (modified group) were treated with modified three-screw fixation and the other 26 patients (conventional group) with conventional two-screw fixation. Outcome measures included operation time, intraoperative blood loss, hospital stays, postoperative complications and the Majeed score at postoperatively 2 months, 3 months, 1 year and the time of implant removal.

RESULTS

The mean operative times and mean blood loss for modified three-screw fixation versus conventional two-screw fixation bilateral were 54.8 ± 10.7 min versus 32.3 ± 9.9 min, and 153.3 mL versus 550.0 mL (p < 0.001), respectively. However, the Majeed score was better in modified group at postoperatively 2 months (75.6 ± 9.5 vs. 69.7 ± 8.3, p = 0.008) and 3 months (80.3 ± 10.7 vs. 75.1 ± 11.9, p = 0.014). There was no statistical difference between two groups at the time of implant removal (82.1 ± 9.3 vs. 80.9 ± 8.8, p = 0.272) and postoperatively 1 year (83.5 ± 7.8 vs 82.6 ± 8.2, p = 0.723). No patients experienced surgical wound infection, deep vein thrombosis, delayed union or nonunion, implant loosening or rupture. One patient complained of tardive unilateral thigh pain at postoperatively 4 months in conventional group.

CONCLUSIONS

Both modified three-screw fixation and conventional two-screw fixation could ultimately afford satisfactory clinical and radiological outcomes with less complication for anterior pelvic ring fractures. The modified three-screw fixation might have better biomechanical strength and faster pelvic rehabilitation.

Effectiveness of surgical fixation for lateral compression type one (LC-1) fragility fractures of the pelvis: a systematic review

OBJECTIVES

To undertake a systematic review of the evidence base for the effectiveness of surgical fixation of lateral compression (LC-1) fragility fractures of the pelvis compared with non-surgical approaches.

SEARCHES

MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials and two international trials registers were searched up to January 2017 (MEDLINE to February 2019) for studies of internal or external fixation of fragility fractures of the pelvis.

PARTICIPANTS

Patients with lateral compression pelvic fractures, sustained as the result of a low-energy mechanism, defined as a fall from standing height or less.

INTERVENTIONS

Surgery using either external or internal fixation devices. Conservative non-surgical treatment was the defined comparator.

OUTCOME MEASURES

Outcomes of interest were patient mobility and function, pain, quality of life, fracture union, mortality, hospital length of stay and complications (additional operative procedures, number and type of adverse events and serious adverse events).

QUALITY ASSESSMENT AND SYNTHESIS

The Joanna Briggs Institute Checklist for Case Series was used to assess the included studies. Results were presented in a narrative synthesis.

RESULTS

Of 3421 records identified, four retrospective case series met the inclusion criteria. Fixation types were not consistent between studies or within studies and most patients had more than one type of pelvic fixation. Where reported, mobility and function improved post-surgery, and a reduction in pain was recorded. Length of hospital stay ranged from 4 days to 54 days for surgical fixation of any type. Reported complications and adverse outcomes included: infections, implant loosening, pneumonia and thrombosis. Use of analgesia was not reported.

CONCLUSIONS

There is insufficient evidence to support guidance on the most effective treatment for patients who fail to mobilise after sustaining an LC-1 fragility fracture.

TRIAL REGISTRATION NUMBER

CRD42017055872.

BIOMECHANICAL ANALYSIS OF DIFFERENT SURGICAL STRATEGIES FOR THE TREATMENT OF ROTATIONALLY UNSTABLE PELVIC FRACTURE USING FINITE ELEMENT METHOD

A rotationally unstable pelvic fracture can lead to loss of function and limit moving ability. Immediate fracture fixation is needed for patients with the pelvic fractures. However, it may be difficult to evaluate different surgical strategies for the fracture treatments due to variations in patients’ anatomies and surgical techniques. Thus, the purpose of the present study was to analyze the biomechanical performances of the intact, injured, and treated pelvises based on different physiological movements of the spine using finite element method. Three-dimensional musculoskeletal finite element models of the spine-pelvis-femur complex were developed. The intact pelvis, the rotationally unstable pelvis, and six types of pelvic fixation techniques were analyzed. Additionally, seven types of physiological movements of the spine were also considered. The results showed that the posterior iliosacral screws combined with lower and anterior plate (PIS-LAP) had good fixation stability, lower plate stress, and lower pelvic stress. However, the PIS-LAP increased the stress of the posterior iliosacral screws. The right lateral bending, left lateral bending, and flexion significantly affect all the biomechanical performances compared to the other physiological movements of the spine. The present study can provide engineers and surgeons with the understanding of the biomechanics of various fixation techniques during different physiological movements for the treatment of rotationally unstable pelvic fractures.

Minimally invasive internal fixator for unstable pelvic ring injuries with a pedicle screw-rod system: a retrospective study of 23 patients after 13.5 months

PURPOSE

Pelvic ring fractures are challenging injuries and require effective treatment due to the frequently compromised patient condition. The aim of this study was to evaluate the outcome of unstable pelvic ring injuries treated with a minimally invasive pedicle screw-rod system.

METHODS

Retrospective analysis was performed for patients with an unstable pelvic ring injury that were treated with a minimally invasive anterior internal pelvic fixator (INFIX) with or without a posterior pedicle screw-rod fixator (6/2012-4/2015). The quality of reduction was evaluated by the Tornetta and Matta criteria and the clinical outcome was evaluated by the Majeed scores. Further evaluation included the operation time, intraoperative blood loss, and complication rate.

RESULTS

A total of 23 patients (12 males and 11 females) with a mean age of 37.6 years (range 10-65 years) and a follow-up of 13.5 months (6-27 months) were evaluated. The Tile classification showed 13 type B (B1 = 6, B2 = 4, and B3 = 3) and 10 type C (C1 = 7 and C2 = 3) fractures. Mean operation time and intraoperative blood loss were 24.8 min (20-30 min) and 20.4 ml (16-29 ml) for an anterior INFIX (n = 13), and 60 min (45-70 min) and 150 ml (115-168 ml) when combined with a posterior pedicle screw-rod fixator (n = 10). Quality of reduction was excellent in 13, good in 6, and fair in 4 patients, with no signs of heterotopic ossification. Clinical results after 6 months were excellent in 14 patients, good in 6, fair in 2, and poor in 1. Unilateral thigh paresthesia was seen in 2 patients which resolved after implant removal.

CONCLUSIONS

The INFIX appears to be a safe and minimally invasive surgical technique which can effectively be combined with posterior pedicle screw-rod fixation. It also can be applied for the definitive treatment of vertically and/or rotationally unstable pelvic ring injuries, especially in severely compromised patients with a high mortality risk.

Sacroiliac screw versus a minimally invasive adjustable plate for Zone II sacral fractures: a retrospective study

OBJECTIVE

Fracture line of the sacrum always involves the Zone II region because sacral foramina are anatomically and physiologically weak regions of the sacrum. The purpose of this study is to compare the therapeutic effects of a sacroiliac screw and a minimally invasive adjustable plate (MIAP) for Zone II sacral fractures.

METHODS

Patients with unilateral Zone II sacral fractures fixed with a unilateral sacroiliac screw or MIAP from August 2009 to January 2016 were recruited into this study and were divided into two groups: group A (sacroiliac screw) and group B (MIAP). Surgical time, blood loss, frequency of intraoperative fluoroscopy, and relative complications were reviewed. Radiographs and CT scans were routinely acquired to evaluate the fracture displacement and reduction quality. Fracture healing was evaluated in the radiographs at each follow-up. Functional outcome was assessed based upon the Majeed scoring system at the final follow-up.

RESULTS

Thirty-one patients in group A and thirty-nine patients in group B were included in this study. No significant differences in average surgical time (P = 0.221) or blood loss (P = 0.234) were noted between group A and group B. The mean frequency of intraoperative fluoroscopy was 15.74±2.98 in group A and 6.08±1.94 in group B (P = 0.000). All fractures healed well within four months in all patients, and the healing time exhibited no significant difference between the two groups (P = 0.579). Satisfactory rates of reduction quality and functional outcome were not statistically different between the two groups (P > 0.05). The complication rate was 16.13% (5/31) in group A and 5.13% (2/39) in group B (P = 0.222).

CONCLUSION

MIAP has a fixation effect and exhibits reduction potential for Zone II sacral fractures. Favourable radiographic and functional results could be obtained through the MIAP technique, which is easy to conduct without pre-contouring. Compared with the unilateral S1 sacroiliac screw technique, repeated projections and iatrogenic sacral injury can be avoided.

Anterior subcutaneous internal fixator (INFIX) versus plate fixation for pelvic anterior ring fracture

The aim of this study was to compare the clinical outcomes in patients with unstable anterior pelvic ring fractures after treatment with anterior subcutaneous internal fixator (INFIX) or plate fixation. We performed a retrospective study from August 2015 to October 2017. A consecutive series of 74 patients who underwent surgical treatment of their anterior pelvic ring (35 treated with INFIX and 39 treated with plates) were studied. Data collected included patients’ demographic data, injury severity score (ISS), AO/OTA classification, injury mechanism, time to surgery, procedure time, and blood loss. The quality of postoperative reduction were assessed by postoperative radiographs using the Tornetta and Matta method. Functional outcome was evaluated using Majeed scoring system. In the INFIX group, ten patients developed LFCN paralysis, one patient suffered from superficial infection. Three screw loosening cases and two wound infection cases occurred in the plate group. INFIX is relatively minimally invasive and time-saving than the reconstruction plate in the treatment of anterior pelvic ring fracture. However, plate fixation increases the rate of anatomic reduction of the pelvic anterior ring fracture. Plates also provide a higher functional outcome compared with INFIX. INFIX is especially suitable in patients with urological injury, which can also decrease the wound infection rate.

Robot-assisted Minimally-invasive Internal Fixation of Pelvic Ring Injuries: A Single-center Experience

Objective

To investigate the indications, surgical strategy and techniques, safety, and efficacy of robot‐assisted minimally‐invasive internal fixation of pelvic ring injuries.

Methods

The clinical data of 86 patients with anterior and posterior pelvic ring injuries who underwent robot‐assisted minimally‐invasive internal fixation were retrospectively analyzed. The patients included 57 men and 29 women aged between 22 and 75 years, with an average age of (40.2 ± 13.6) years. According to the Tile classification, there were 5 (5.8%) type A2, 48 (55.8%) type B, and 33 (38.4%) type C fractures. The surgical plans were formulated based on the injury type of the pelvic ring, the effectiveness of the reduction, and the integrity of the osseous channel. Posterior pelvic ring injuries were treated with robot‐assisted percutaneous cannulated screw fixation of the sacroiliac joint. Anterior pelvic ring injuries were treated with robot‐assisted percutaneous cannulated screw fixation of the pubic ramus, INFIX fixation, or a “hybrid” fixation. The surgical complications and the efficacy of the surgical treatments were analyzed.

Results

A total of 274 screws were inserted with robotic assistance, of which 262 screws were successfully inserted to a satisfactory position on the first attempt. The number of screws placed per person was 3.2 on average, and the average operation time was 175 min (35–280 min). Fluoroscopies were performed an average of 29.1 times (range, 9–63 times), and it took 6.1 s to place each screw. There were 13 unsatisfactory guiding needle placements during the surgeries, among 7 of which cutting or penetration of the cortex was re‐planned until satisfactory insertions; 1 penetrated the pubic cortex, causing hemorrhage of the “crown of death,” and was changed to “hybrid surgery”. The robot‐assisted surgical wounds all healed by primary intention with satisfactory position and precision of screw insertions. All patients were followed up for 3–6 months, with an average of 4.2 months. There were two postoperative fixation failures, in which both patients had separated symphysis pubes after hybrid surgery. The average Majeed score at the last follow‐up was 92.4 points.

Conclusions

Robot‐assisted surgery is accurate and minimally invasive, with a high success rate for one‐time screw placement and satisfactory clinical results. The indications and surgical strategy should be rigorously selected, the level of surgical techniques mastered, and the operating procedures standardized, all of which may help to prevent surgical complications. Robot‐assisted surgery provides a novel modality for the minimally‐invasive treatment of pelvic ring injuries.

Combined Pelvic Ring Disruption and Acetabular Fracture: Outcomes Using a Sequential Reduction Protocol and an Anterior Subcutaneous Pelvic Fixator (INFIX)

OBJECTIVE

The purposes of this article were to (1) compare our combined pelvic ring and acetabular fracture patients' rate of mortality and Injury Severity Score (ISS) to those of patients with isolated injuries at our center and to those with combined injuries as reported in the literature, (2) describe our treatment algorithm using the INFIX for these combination injuries, and (3) report our patients' radiographic and functional outcomes.

DESIGN

Retrospective IRB-approved case series and literature review.

SETTING

US Level 1 Trauma Center.

PATIENTS/PARTICIPANTS

Thousand six hundred ninety-seven with acetabular or pelvic ring injury, 174 patients with combination pelvic ring acetabular injuries, and 39 patients with 41 acetabular injuries treated with a surgical protocol.

INTERVENTION

Pelvic ring reduction using INFIX and posterior fixation followed by acetabular reduction fixation. Anterior injury fixed with INFIX.

MAIN OUTCOME

Mortality, ISS, pelvic reduction by Keshishyan index, acetabular reduction by the Matta criteria, and functional outcome by the Majeed score.

RESULTS

Mortality was 5.7% and ISS was 12.5 for 174 combined injury patients. In the 39 patients with 41 injuries, excellent pelvic reduction was found in 39, and acetabular reduction was anatomic in 25 (61%), imperfect in 12 (29%), and poor in 4 (10%). Clinically 78% of the patients had good or excellent outcome and 22% had a fair or poor outcome. Nonanatomic acetabular reduction, persistent sciatic nerve palsy, and heterotopic ossification associated with poor clinical outcome.

CONCLUSIONS

Our treatment protocol resulted in excellent pelvic reduction, anatomic acetabular reduction in 61% of patients, and 78% good to excellent clinical outcome.

LEVEL OF EVIDENCE

Case series Level IV.

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

INTRODUCTION

INFIX 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.

METHODS

Ten 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.

RESULTS

We 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.

DISCUSSION

Our 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.

Digital Anatomy to Improve Screw Insertion Techniques for Plate-Screw Fixation of the Pubic Body

Objectives

This study aims to investigate screw insertion sites on the pubic body and the safe screw insertion parameters of a plate-screw fixation system based on the premise of avoiding damage to the inguinal canal and disruption of the rectus abdominis at the pubic symphysis and pubic crest.

Research Methods

Excluding cases with poor image quality, tumors, malformations, and fractures, the data of 80 healthy adults (40 males and 40 females aged from 21 to 83 years old, with an average age of 51.65 years) undergoing a computed tomography (CT) scan of the pelvis between January and June of 2017 were collected from Shandong Provincial Hospital. The CT scans were imported to Mimics® software to reconstruct three-dimensional pelvic models. A 3.5 mm pelvic reconstruction plate was placed starting at the outer edge of the pubic tubercle and along the pelvic brim. The two innermost screw insertion sites were marked. The safe range for the screw insertion sites was then determined. The screw insertion plane was selected to measure the safe screw insertion parameters. The length of the screw, the direction of insertion, and intersex differences were then explored via statistical analyses.

Results

The medial inclination angles (MIAs) of the screw insertion plane for males and females were 30.42±7.95° and 32.88±10.65°, respectively, with no statistically significant differences. For the medial screw, the maximum anterior inclination angle (MAIA), the maximum screw length, and the maximum posterior inclination angle (MPIA) were 46.51±4.01°, 12.40±9.53 mm, and 11.78±10.22° on average, respectively, with no significant differences by gender (P>0.05). For the lateral screw, the MAIA was 10.35±9.46° and showed no gender differences (P>0.05), but the male group had a greater MPIA (male 11.80±11.00° vs. female 6.23±7.91°, P<0.05) and maximum screw length (male 55.71±6.36 mm vs. female 48.68±8.65, P<0.001). For the tangential screw, the maximum screw length, MIA, and anterior/posterior inclination angle (APIA) were 52.19±8.33 mm, 31.65±9.42°, and 7.53±10.18°, respectively, with no significant differences in the angles by gender (both P>0.05), although the screw length in the male group was significantly longer than that in the female group.

Conclusions

Insertion of two screws into the pubic body through a plate from the lateral side of the pubic tubercle is safe and can maintain the origin of the rectus abdominis and the integrity of the inguinal canal compared to traditional plate-screw fixation. Considering that the pubic body is thinner on the lateral side, we suggest a more medial inclination angle for the lateral screw.

A cost minimization analysis comparing minimally-invasive with open reduction surgical techniques for pelvic ring fracture

The aim of the present study was to compare the in-hospital direct medical costs of patients with pelvic fracture treated with minimally invasive surgery (MIS) or open reduction and internal fixation (ORIF). A retrospective, single-center, cohort, and comparative study was performed. Administrative information and clinical results, in addition to cost data, were collected and analyzed. A cost minimization analysis method was used to evaluate the costs of two different surgical techniques. A total of 128 patients diagnosed with pelvic fracture were included in this study; 62 were treated with MIS and 66 underwent ORIF. No significant difference was observed between the 2 groups in terms of patients' clinical baseline characteristics. The operative time, length of incision, intra-operative blood loss, and post-operative length of stay in the MIS group were significantly different compared with those in the ORIF group. The cost-minimization analysis demonstrated that the cost effectiveness of MIS was better than ORIF as the MIS was associated with a significantly lower total in-hospital direct medical cost ($8,900 vs. $5,786, P=0.032), compared with ORIF. The cost-minimization analysis demonstrated that for similar clinical baseline characteristics as well as outcomes, there were differences in direct hospitalization cost of two surgical techniques, and MIS had a lower cost on average than ORIF.

Complications Following Internal Fixator in the Treatment of Pelvic Fracture

The aim of this systematic review was to investigate the incidence of complications of the internal fixator in the treatment of anterior pelvic ring injury. The literature was comprehensively searched from 1980 to January 2017 to identify potential studies. Six studies involving 272 cases of anterior pelvic ring injury treated with the internal fixator were included in this meta-analysis. The rates of wound infection, heterotopic ossification, nerve paresthesia, pain, and fracture dislocation were 5.7%, 35.1%, 28.2%, 3.7%, and 3.0%, respectively. This new technique should be prudently used to treat pelvic fractures. [Orthopedics. 2019; 42(1):e7-e13.].

Patient Weight-bearing after Pelvic Fracture Surgery-A Systematic Review of the Literature: What is the Modern Evidence Base?

Background

Little attention in the literature appears to have been paid to the issue of postoperative weight-bearing protocols for different injury patterns after pelvic fracture surgery. The primary aim of this study is to review the currently available literature to define the level of available evidence used to inform surgical decisions on weight-bearing after pelvic fracture surgery. Secondary aims are to assess the published methods of fracture classification, surgical management, and assessment or reporting of patient outcomes.

Methods

A systematic review of the English language literature from 1990 to 2016 was undertaken. Eligible papers were all papers reporting minimum 6-month outcomes following surgery for pelvic fractures in adults. Exclusion criteria included pathological fractures or those resulting from penetrating injury, solely osteoporotic fractures, or series with less than 6 months of follow-up data.

Results

There is very little published scientific data to inform the treating surgeon on postoperative weight-bearing protocols after pelvic fracture surgery, with no randomized trials and only 1 paper out of 122 stating this as a primary aim. More than half of the papers published did not state what postoperative protocol was employed. There is no standardization of outcome measures, with less than 20% of papers using the most common validated outcome scoring system; in contrast, there is good agreement on the use of either the Tile (75%) or Burgess and Young (20%) classification.

Limitations

Due to the lack of published studies looking at the topic of postoperative weight-bearing after pelvic fractures, no specific recommendations are possible. As large numbers of papers were included, they were not individually assessed for bias.

Conclusion

A review of postoperative weight-bearing regimes reveals a nonexistent scientific evidence base from which to make recommendations, although a consensus strategy has been identified. Future research needs to be directed at this topic, as has already been the case in numerous other fracture areas, since the advantages of early mobility are potentially significant. The reported methodology for assessing and reporting patient outcomes after pelvic fracture surgery reveals no consistent standards, and the majority of papers use no specific outcome scoring system.

How to cite this article

Rickman M, Link B-C, Solomon LB. Patient Weight-bearing after Pelvic Fracture Surgery-A Systematic Review of the Literature: What is the Modern Evidence Base? Strategies Trauma Limb Reconstr 2019;14(1):45-52.

A novel hybrid fixation (percutaneous anterior pelvic bridge with K-wire) for the treatment of traumatic pelvic ring injury: A prospective study

BACKGROUND

The aim of the study was to introduce a novel percutaneous technique for the treatment of pelvic ring injuries using a percutaneous anterior pelvic bridge (PAPB) with K-wire.

METHODS

From December 2010 to November 2016, a prospective study of 86 patients with anterior pelvic ring fracture (42 utilizing PAPB with K-wire and 44 utilizing PAPB). Patient data was retrieved from electronic charts. Radiological results were assessed based on the Matta criteria system to evaluate the quality of the reduction and time to union. Functional outcomes were evaluated using the Majeed scoring system. Postoperative complications were also recorded.

RESULTS

Age, sex, cause of injury, type of fracture, functional recovery, American Society of Anesthesiologists classification, union time, Majeed scoring and complications did not differ significantly between the two groups. The quality of the reduction and pain scoring differed between groups (all p-values < 0.05). Group A got better reduction and less pain scoring.

CONCLUSIONS

The novel percutaneous technique with hybrid fixation using PAPB with K-wire is a successful alternative for the treatment of pelvic ring injuries, which results in better quality of reduction and less pain scoring outcomes comparing to PAPB. May the PAPB + K-wire could provide more stability.

Clinical and radiological short-term outcomes of pubic symphysis diastasis treated with modified pedicle screw-rod fixation

PURPOSE

Pubic symphysis diastasis with an incidence of approximately 20% in pelvic fractures is a severe lesion which needs to be treated properly. The objective of this retrospective study was to describe and evaluate the clinical and radiological outcomes including its advantages and limitations of this modified minimal invasive technique.

METHODS

Totally 29 patients with pubic symphysis diastasis, with or without posterior ring instability, were treated by modified pedicle screw-rod fixation (modified PSRF) between January 2010 and December 2016. The duration from injury to surgery, operation time, intraoperative blood loss as well as complications were recorded. During follow-up, the functional outcomes were assessed according to the Majeed evaluation criteria 1 year postoperatively. The evaluation of the postoperative reduction quality was carried out according to Matta criteria.

RESULTS

According to Tile classification, there were 9 cases of Type B1 underwent only anterior-modified PSRF and 20 cases of Type C1 experienced anterior-modified PSRF combined with posterior fixation. The duration from injury to operation, operation time and intraoperative blood loss were 3.27 days (range 1-6 days), 42.07 min (range 38-45 min), and 46.14 ml (range 40-55 ml). The results of reduction quality were rated as excellent in 16, good in 11 and fair in 2 based on Matta criteria. The Majeed functional scores ranged from 68 to 95 and there were excellent in 15, good in 12 and fair in 2. No patients experienced incision infection. Slight loosening of middle-two screws was verified during follow-up in one patient. Two patients underwent femoral nerve palsy. Irritation to the LFCN was detected in four patients.

CONCLUSIONS

Modified PSRF can be performed as an alternative to manage pubic symphysis diastasis due to its merits of minimal invasive, less blood loss, less soft tissue injuries as well as shorter operation time, even with the early weight-bearing.

TRIAL REGISTRATION

Researchregistry3905.

Three-dimensional (3D) Printing Technology Assisted by Minimally Invasive Surgery for Pubic Rami Fractures

The feasibility of three-dimensional (3D) printing technology combined with minimally invasive surgery in the treatment of pubic rami fractures was explored. From August 2015 to October 2017, a series of 30 patients who underwent surgical stabilization of their anterior pelvic ring (all utilizing the 3D printing technology) by one surgeon at a single hospital were studied. The minimally invasive incisions were made through anterior inferior cilia spine and pubic nodule. Data collected included the operative duration, the blood loss, the damage of the important tissue, the biographic union and the recovery of the function after the operation. Measurements on inlet and outlet pelvic cardiograph were made immediately post-operation and at all follow-up clinic visits. The scores of reduction and function were measured during follow-up. Results showed that the wounds of 30 patients were healed in the first stage, and there was no injury of important structures such as blood vessels and nerves. According to the Matta criteria, excellent effectiveness was obtained in 22 cases and good in 8 cases. According to the functional evaluation criteria of Majeed, excellent effectiveness was obtained in 21 cases and good in 9 cases. It was suggested that the 3D printing technology assisted by minimally invasive surgery can better evaluate the pelvic fracture before operation, which was helpful in plate modeling, and can shorten surgery duration and reduce intraoperative blood loss and complications. The positioning accuracy was improved, and better surgical result was finally achieved.

[Treatment of unstable pelvic fractures by cannulated screw internal fixation with the assistance of three-dimensional printing insertion template]

Objective

To evaluate the effectiveness of unstable pelvic fractures treated by cannulated screw internal fixation with the assistance of three-dimensional (3D) printing insertion template.

Methods

The clinical data of 10 patients who underwent surgical treatment for unstable pelvic fractures by cannulated screw internal fixation with the assistance of 3D printing insertion template between May 2015 and June 2016 were retrospectively analysed. There were 7 males and 3 females with an average age of 37.5 years (range, 20-58 years). The causes of injury included falling from height in 5 cases, crushing from heavy load in 1 case, and traffic accidents in 4 cases. The interval from injury to admission was 1-5 hours (mean, 3.1 hours). The fracture situation included 6 cases of sacral fracture, 1 case of right sacroiliac joint dislocation, and 3 cases of iliac bone fracture. There were 10 cases of superior and inferior pubic rami fracture, including 3 cases on the left side (2 cases of suprapubic fracture adjacent to symphysis pubis), 2 cases on the right side, and 5 cases on the bilateral. All fractures were classified according to the Tile system, there were 4 cases of type B2, 1 of type B3, 4 of type C1, and 1 of type C2. The radiological outcome was evaluated by Matta scale, and the positions of the iliosacral screw and superior pubic ramus screw were evaluated according to 3D reconstruction of CT postoperatively. The functional outcome was evaluated by Majeed function scale.

Results

The average time of each screw implantation was 30 minutes, and the average blood loss per screw incision was 50 mL. The time of implantation of each sacroiliac screw was 24-96 seconds (mean, 62 seconds), and the time of implantation of each suprapubic screw was 42-80 seconds (mean, 63.2 seconds). The hospitalization duration was 17-90 days (mean, 43.7 days). All incisions healed by first intention. All patients were followed up 12-22 months (mean, 15.6 months). The radiological outcome was excellent in 8 cases and good in 2 cases according to Matta scale; and 3D reconstruction of CT demonstrated that all the 9 iliosacral screws were placed as type Ⅰ, and all the 13 suprapubic ramus screws were placed as grade 0 on the first postoperative day. No complication such as neurovascular injury, screw back out or rupture, or secondary fracture displacement was observed during the follow-up. At 6 months after operation, the X-ray films showed good fracture healing in all the 10 patients. The functional outcome was excellent in 9 cases and good in 1 case according to Majeed scale at 1 year after operation. One patient sustained Tile C2 pelvic disruption complicated with L ₅ nerve root injury achieved complete nervous functional recovery at last follow-up.

Conclusion

It has advantages of precise screw insertion and lower risk of neurovascular injury to treat unstable pelvic fractures by cannulated screw internal fixation with the assistance of 3D printing insertion template, which can be a good alternative for the treatment of unstable pelvic fractures.

Minimally invasive treatment for anterior pelvic ring injuries with modified pedicle screw-rod fixation: a retrospective study

Background

Pelvic ring injuries constitute only 2 to 8% of all fractures; however, they occur in 20% of polytrauma patients. High-energy pelvic fractures often result in mechanical instability of the pelvic ring. Successful treatment of unstable pelvic ring fractures remains a challenge for orthopedic surgeons. This study presents a novel internal fixation method for stabilizing unstable anterior pelvic ring fractures using a minimally invasive modified pedicle screw-rod fixation (MPSRF) technique.

Methods

This retrospective study included six patients with unstable pelvic ring injuries who underwent MPSRF, with or without posterior fixation. Intraoperative parameters such as blood loss, operative time, complications, and quality of reduction (Matta criteria) were recorded and evaluated by a blinded reviewer.

Results

In the present clinical series, the mean operative times and mean blood loss for unilateral versus bilateral anterior ring fixations were 176.0 min versus 295.6 min, and 153.3 mL versus 550.0 mL, respectively. No iatrogenic neuropraxia of the lateral femoral cutaneous nerve or femoral nerve palsy occurred. The reduction quality, graded by the Matta criteria, was excellent in five patients and good in one patient.

Conclusions

There were no infections, delayed unions, nonunions, or loss of reductions during the follow-up period. Only one patient suffered from a broken rod at 4 months postoperatively. The modified technique represents a novel, minimally invasive procedure for the treatment of anterior pelvic ring fractures and offers a reliable and effective alternative to currently available surgical techniques.

Anterior Subcutaneous Internal Pelvic Fixation/INFIX: A Systemic Review

INTRODUCTION

The purpose of this article is to review the available literature on anterior subcutaneous internal pelvic fixation (ASIPF) to identify indications, clinical and radiographic outcomes, and compare these with alternative fixation methods.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, a systematic search on PubMed and Google Scholar was performed. Articles included were in the English language or English translations and published between 2007 and 2018. Studies included were appraised with narrative data synthesis.

RESULTS

Twenty-five articles with 496 patients were included. These included 17 case series, with 3 case reports reporting adverse events.

CONCLUSIONS

ASIPF and the appropriate posterior fixation resulted in healing of pelvic ring injuries in 99.5% of cases. Indications include unstable pelvic ring injuries with the appropriate posterior fixation. Radiographic parameters and outcome measures were infrequently reported. ASIPF is a valuable tool for reduction and fixation in unstable pelvic ring injuries. Complications include lateral femoral cutaneous nerve irritation (26.3%); heterotopic ossification (36%); infection (3%); and femoral nerve palsy (1%), which is likely related to placing the bar and screws too deep.

Management of Pelvic and Acetabular Fractures in the Obese Patient

Acetabular and pelvic ring injuries in obese patients are difficult to treat. Obese patients require great attention to detail during the trauma evaluation to prevent medical and anesthetic complications in the perioperative period. Radiographic evaluation is often compromised by modalities available and loss of resolution with plain film imaging. Patient positioning must be meticulous to ensure stability on the bed while allowing access to the operative site, preventing pressure necrosis, and minimizing ventilation pressure. Complications after surgical treatment are common and often due to infection and loss of fixation. Careful technique can mitigate but not prevent these complications.

Minimally invasive anterior pelvic internal fixation: An anatomic study comparing Pelvic Bridge to INFIX

OBJECTIVES

Anterior external fixation for pelvic ring fractures has shown to effectively improve stability and reduce mortality. However, these fixators can be associated with substantial morbidity such as pin tract infection, premature loss of fixation, and decreased quality of life in patients. Recently, two new methods of subcutaneous anterior pelvic internal fixation have been developed; the INFIX and the Pelvic Bridge. These methods have the purported advantages of lower wound complications, less surgical site pain, and improved quality of life. We sought to investigate the measured distances to critical anatomic structures, as well as the qualitative and topographic differences notable during implantation of both devices in the same cadaveric specimen.

MATERIALS AND METHODS

The Pelvic Bridge and INFIX were implanted in eleven fresh cadavers. Distances were then measured to: the superficial inguinal ring, round ligament, spermatic cord, lateral femoral cutaneous nerve (LFCN), femoral nerve, femoral artery, and femoral vein. Observations regarding implantation and topography were also recorded.

RESULTS

The INFIX had greater measured distances from all structures except for the LFCN, in which its proximity placed this structure at risk. Neither device appears to put other critical structures at risk in the supine position. Significant implantation and topographic differences exist between the devices. The INFIX application lacked "safety margins" concerning the LFCN in 10/11 (90.9%) specimens, while Pelvic Bridge placement lacked "safety margins" with regard to the right superficial ring (1/11, 9%) and the right spermatic cord (1/11, 9%).

CONCLUSIONS

Both the Pelvic Bridge and INFIX lie at safe distances from most critical pelvic structures in the supine position, though INFIX application places the LFCN at risk.

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

Background

Anterior 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.

Methods

Either 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.

Results

The 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.

Conclusions

Application 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 registration

Research Registry UIN: researchregistry2776.

Management of the open book APC II pelvis: Survey results from pelvic and acetabular surgeons in the United Kingdom

The results of this questionnaire show that the opinion of pelvic and acetabular surgeons in the UK and Republic of Ireland vary as to the best method of fixation for APC II pelvic injuries. A single anterior plate and single sacroiliac joint (SIJ) screw was the most popular fixation method, chosen by 34%. 74% favour a single, opposed to two orthogonal anterior plates. Posterior fixation supplementing anterior plating is preferred by 63% of surgeons, 58% use a single versus 42% two SIJ screws. Case by case assessment and intraoperative screening to assess stability is essential when considering whether to stabilise the SIJ.

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.].

Anterior subcutaneous internal fixation of the pelvis - what rod-to-bone distance is anatomically optimal?

INTRODUCTION

Anterior fixation of the pelvis using subcutaneous supra-acetabular pedicle screw internal fixation (INFIX) has proven to be a useful tool by avoiding the downsides of external fixation in patients where open fixation is not suited. The purpose of this study was to find a rod-to-bone distance for the INFIX that allows for minimal hazard to the inguinal neuro-vascular structures and, at the same time, as little as possible interference with the soft tissues of the proximal thigh when the patient is sitting.

METHODS

An INFIX was applied to 10 soft-embalmed cadaver pelvises with three different rod-to-bone distances. With each configuration, the relations of the rod to the neuro-vascular and the muscular surroundings were measured in supine and sitting position.

RESULTS

Except for the femoral artery, vein and nerve, all investigated anatomical structures of the groin were under compression with a rod-to-bone distance of 1cm. With a rod-to-bone distance of 2cm most of the anatomical structures were safe in supine position, although less than with 3cm. With hip flexion some structures got under compression, especially the lateral femoral cutaneous nerve (LFCN, 80%) and the anterior cutaneous branches of the femoral nerve (ACBFN, 35%). With a rod-to-bone distance of 3cm almost all anatomical structures were safe in supine position, while with hip flexion most superficial structures of the proximal thigh got under compression, especially the LFCN (75%) and the ACBFN (60%).

CONCLUSIONS

Aiming for a rod-to-bone distance of 2cm is the safest way with regard to compression of the femoral neuro-vascular bundle and at the same time leads to the least compression of more superficial structures like the LFCN, the ACBFN, or the sartorius and the rectus femoris muscles in sitting position.

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

Stabilization after a pelvic fracture can be accomplished using multiple techniques. The anterior external fixator has been traditionally used in variety of unstable pelvis either singly or in combination of posterior screws. These devices are cumbersome and restrict side turning and sitting particularly in obese patients. An alternative, anterior subcutaneous pelvic internal fixation technique (ASPIF) was developed which is well tolerated by patients for mobility and comfort and biomechanically more stable construct Complications of this construct included irritation of the lateral femoral cutaneous nerve, femoral nerve palsy &heterotypic ossification with reduced rates of infections and aseptic loosening as compared to external fixator. Bladder incarceration following treatment has never been reported and we encountered such a problem during management which we want to highlight.

Biomechanical comparison of supraacetabular external fixation and anterior pelvic bridge plating

Unstable pelvic ring injuries are complex and risky injuries due to high morbidity and mortality. Although anterior pelvic external fixator is a suitable method for rapid stabilization of an injured pelvic ring, due to some disadvantages such as high complication rate, nerve damage, and difficulties of patient's mobility and comfort, there has recently been increased searching for alternative methods for stabilization of the pelvic ring. Pubic symphysis zone freely moves in pelvic models. This study aims to evaluate the biomechanical stability of anterior pelvic bridge plating and compare it with supraacetabular external fixators in an untreated unstable pelvic fracture model. Samples were loaded statically with 2-mm/min loading rate in single leg standing position. Maximum load was 2.3 kN. When loading the samples, photographs were taken continuously. Stiffness values were calculated from the load displacement curves. Some reference parameters were described and were measured from unloaded and 2.3-kN-loaded photographs of the test. The mean stiffness values were 491.14 ± 52.22, 478.55 ± 41.44, and 470.25 ± 44.51 N/mm for anterior pelvic bridge plating group, supraacetabular external fixator group, and Control group, respectively. According to the measured parameters from photographs, the mean displacement at the pubic symphysis was 4.7 ± 0.32, 15.8 ± 2.01, and 18.2 ± 0.47 mm for anterior pelvic bridge plating, supraacetabular external fixator, and Control group, respectively. The highest displacement in the pubic symphysis was found in Control group, and minimum displacement was observed in anterior pelvic bridge plating group. When the perpendicular distance between the right and left lower end of ischium was examined, it was observed that displacement was minimum in anterior pelvic bridge plating group compared to other two groups, regarding to the high stability of pubic symphysis. In conclusion, this study revealed superiority of anterior subcutaneous plate fixation with biomechanical results.

Treatment of type B pelvic fracture using anterior subcutaneous internal fixator with triple pedicle screws: a new surgical technique

INTRODUCTION

To evaluate the clinical outcomes of anterior subcutaneous internal fixator using triple pedicle screws (ASIF/TPS) in the treatment of unstable type B pelvic fracture compared with open reduction internal fixation (ORIF).

MATERIALS AND METHODS

This was a retrospective cohort study of 26 patients with type B unstable fractures that underwent ASIF/TPS and 26 similar patients that underwent ORIF using plates and screws. Intraoperative blood loss, operating time, and post operation hospitalization duration were compared. Anteroposterior, inlet, and outlet X-rays and 3D computed tomography were obtained. Pain, numbness, sexual dysfunction, and activity were evaluated at every follow-up visit until the implants were removed. The Majeed score was used to assess the clinical and radiological outcomes.

RESULTS

Blood loss, operating time, and hospitalization duration were less (all P < 0.001) in the ASIF/TPS group compared with the ORIF group. The clinical and radiological outcomes of the ASIF/TPS group after a mean follow-up of 6 months were excellent and good in 80.8%, and moderate in 19.2%. In comparison, the results of the ORIF group were excellent and good in 65.4%, moderate in 29.0%, and poor in 5.6%. No patient experienced nonunion, delayed union, superficial infection, or deep surgical wound infection. No urethral injury or dysuria occurred in the ASIF/TPS group. Two patients had temporary lateral femoral cutaneous nerve numbness after operation. There were two superficial wound infections in the ORIF group.

CONCLUSIONS

The use of ASIF/TPS with triple pedicle screws could be a reasonable option for the treatment of type B unstable pelvic fractures.

Minimally invasive treatment of unstable pelvic ring injuries with modified pedicle screw-rod fixator

Objective

To evaluate the clinical application of the minimally invasive modified pedicle screw–rod fixator for unstable pelvic ring injuries, including its feasibility, merits, and limitations.

Methods

Twenty-three patients (13 males, 10 females; average age, 36.3 years) with unstable pelvic ring injuries underwent anterior fixation using a modified pedicle screw–rod fixator with or without posterior fixation using a transiliac internal fixator. The clinical findings were assessed using Majeed scores. The quality of reduction was evaluated using the Matta criteria.

Results

Clinical results at 1 year postoperatively were excellent in 14 patients, good in 7, and fair in 2. The two patients with fair results had intermittent pain at the sacroiliac joint because of the posterior implant. One woman complained of persistent pain at the pubic tubercle during sexual intercourse. Iatrogenic neuropraxia of the unilateral lateral femoral cutaneous nerve occurred in three patients. Unilateral femoral nerve palsy occurred in one patient. The quality of fracture reduction was excellent in 12 patients, good in 8, and fair in 3. Heterotopic ossification occurred in eight patients; all were asymptomatic.

Conclusions

Minimally invasive modified pedicle screw-rod fixation is an effective alternative treatment for pelvic ring injuries.

Optimization of technique for insertion of implants at the supra-acetabular corridor in pelvis and acetabular surgery

The technique for application of implants at the sciatic buttress has been well described in the pelvic and acetabular fracture reconstruction literature. We described a new use of the inlet–obturator oblique view for the identification of the anterior inferior iliac spine, which is the entry point of implants, and we provide a detailed fluoroscopic and radiographic description of this view. A small series of 15 patients who underwent an application of an anterior inferior pelvic external (supra-acetabular) fixator via this technique is presented. We consider the use of the obturator oblique for the identification of the entry point unnecessary, and we advocate for the use of only the inlet–obturator oblique and iliac oblique views when implants are applied to the sciatic buttress.

Modified pedicle screw-rod fixation as a minimally invasive treatment for anterior pelvic ring injuries: an initial case series

Background

Unstable pelvic ring injuries often involve high mortality and morbidity. This study was aimed to evaluate the modified minimally invasive pedicle screw–rod fixation for anterior pelvic ring injuries, in the respects of its feasibility, merits, and limitations.

Methods

Twenty-three patients with unstable pelvic ring injuries underwent the modified anterior pedicle screw–rod fixation, with or without posterior fixation. The clinical outcomes were assessed using Majeed scores, and the quality of reduction was evaluated according to the criteria of Matta.

Results

Majeed scores showed that the clinical outcomes at postoperatively 1 year were excellent in 14 patients, good in 7, and fair in 2. One woman complained of persistent pain at the pubic tubercle during sexual intercourse. Iatrogenic neuropraxia of the unilateral lateral femoral cutaneous nerve occurred in 3 patients. Unilateral femoral nerve palsy occurred in 1 patient. The reduction was found to be excellent in 12 patients, good in 8, and fair in 3. Heterotopic ossification occurred in 8 patients, all being asymptomatic.

Conclusions

The modified pedicle screw–rod fixation with the minimally invasive technique offered an effective alternative for unstable anterior pelvic ring injuries.

Midterm Radiographic and Functional Outcomes of the Anterior Subcutaneous Internal Pelvic Fixator (INFIX) for Pelvic Ring Injuries

OBJECTIVE

To describe our experience using the anterior internal pelvic fixator (INFIX) for treating pelvic ring injuries.

DESIGN

Case Series.

SETTING

Level 1 Trauma Center.

PATIENTS

Eighty-three patients with pelvic ring injuries were treated with INFIX. Follow-up average was 35 months (range 12-80.33).

INTERVENTION

Surgical treatment of pelvic ring injuries included reduction, appropriate posterior fixation, and INFIX placement.

OUTCOME MEASUREMENTS

Reduction using the pelvic deformity index and pubic symphysis widening, Majeed functional scores, complications; infection, implant failure, heterotopic ossification (HO), nerve injury, and pain.

RESULTS

All patients healed in an appropriate time frame (full weight bearing 12 weeks postoperation). The average pelvic deformity index reduction (injury = 0.0420 ± 0.0412, latest FU = 0.0254 ± 0.0243) was 39.58%. The average reduction of pubic symphysis injuries was 56.92%. The average Majeed score of patients at latest follow-up was 78.77 (range 47-100). Complications were 3 infections, 1 case of implant failure, 2 cases implantation too deep, 7 cases of lateral femoral cutaneous nerve irritation, and 3 cases of pain associated with the device. HO was seen in >50% of the patients, correlated with increased age (P < 0.007), injury severity score (P < 0.05) but only 1 case was symptomatic.

CONCLUSIONS

The pelvic injuries had good functional and radiological outcomes with INFIX and the appropriate posterior fixation. The downside is removal requiring a second anesthetic, there is a learning curve, HO often occurs, the lateral femoral cutaneous nerve may get irritated which often resolves once the implants are removed. Surgery-specific implants need to be developed.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Epidemiology of pelvic ring fractures and injuries

OBJECTIVE

This study evaluated the pelvic ring fractures and injuries in patients admitted to and treated at this ward between August, 2012 and January, 2014.

METHODS

66 patients were submitted to treatment protocols according to their age, gender, skin color, injury mechanism, location of the trauma, classification of their injuries, emergency intervention, associated injuries, injured side of the body, treatment, and mortality. The most relevant data were classified according to statistic procedures, such as Goodman's association test. Measures were compared with Student's t-test and analysis of variance associated with Tukey's multiple comparison test.

RESULTS

The mean age was 47 years; white race and male gender were most common. Car or truck accident was the most common cause of injuries, which occurred mainly in urban sites. Type A injuries were the most frequent. 16.6% of the cases were submitted to emergency surgery. 42.4% displayed associated injuries. The right side of the body was the most commonly affected side. Non-invasive treatment was most commonly used. Death was the outcome in 3% of the cases, associated to high-energy trauma.

CONCLUSIONS

Pelvic ring fractures and injuries are more often verified among males. In general and among younger individuals, traffic accidents are the most common cause of the injury, while among the elderly, ordinary falls are the most commonly verified cause. The majority of those injuries are suffered in urban areas. Type A fractures are more frequent. The majority of cases do not require emergency intervention nor do they feature associated injuries. Non-invasive treatment is most common and death outcomes are associated to high-energy traumas with severe injuries.

[Percutaneous internal fixation of pelvic fractures. German version]

BACKGROUND

Percutaneous internal fixation of pelvic fractures is increasing in popularity with multiple new techniques reported.

OBJECTIVES

The purpose of this article is to outline the imaging, indication, planning, equipment, surgical technique and complications of these methods.

METHODS

A review of the literature is provided and the techniques for anterior and posterior pelvic stabilization are discussed.

RESULTS

High-quality preoperative CT scans are essential in planning for this technique. The anterior internal fixator ("InFix") is an effective method for stabilizing the anterior ring and should be usually used in conjunction with posterior fixation. Good technique avoids neurovascular injury, which can be a devastating complication. The retrograde anterior column screw (RACS) is a technique that can be used in most patients, although in smaller patients smaller screw diameters may be needed. The entry point for the screw is more lateral in women than men. Iliosacral screws (ISS) are an effective method of posterior stabilization and can be placed using 2D or 3D fluoroscopy, computer navigation or CT navigation.

CONCLUSION

Percutaneous fixation of pelvic fractures requires high-quality imaging and can be aided by computer navigation. Safe techniques are reproducible; however, not all patients and fracture patterns can be treated using these techniques.