Fixation Of Anterior Pelvic Ring Research Articles

Retrospective evaluation of percutaneous 3D-navigated screw fixation for fragility fractures of the sacrum: technical notes and four-year experience

The incidence of fragility fractures of the sacrum is increasing due to demographic changes. In this study, we introduce the 3D-navigated monoportal percutaneous sacroiliac screw fixation (PSS) as a technical advancement for treating fragility fractures of the sacrum. We included all patients who underwent the 3D-navigated monoportal PSS for fragility fractures of the sacrum. The fractures were classified using the Fragility Fractures of the Pelvis score (FFP). We provide a step-by-step illustration of the surgical technique. The objective of this study was to assess the feasibility and safety of the investigated technique. Forty-six patients (36 female, 10 male) with a median age of 81.5 years were included in the study. The fracture classification revealed 23 FFP2 (50%), 5 FFP3 (11%), and 18 FFP4 (39%) fractures. In 35 cases (76%), only transsacral screws were implanted in S1 and S2, with an average incision-to-suture time of 52.6 min. The remaining eleven patients underwent additional anterior pelvic ring fixation, lumbar instrumentation, or kyphoplasty. There were no instances of nerve root, vascular, or pelvic organ injuries. The median postoperative in-hospital stay was six days. Out of the 36 patients who were followed up, four patients required revision surgery due to screw loosening. No significant risk factor for screw loosening was identified in the multiple regression analysis. The presented monoportal PSS technique for fragility fractures of the sacrum is a promising minimally invasive approach with a low complication rate and excellent short-term outcomes.

The Bridging Infix: a modified, minimally invasive subcutaneous anterior pelvic fixation technique

Various methods for anterior pelvic ring fixation have been described in the literature, each with specific advantages and disadvantages. We describe a modified minimally invasive subcutaneous technique for anterior fixation: the Bridging Infix. It combines the benefits of internal plate fixation with external fixator principles. We merged and modified features of the existing INFIX and Pelvic Bridge techniques during the design. Similar to these techniques, we use plate-rods typically used during occipitocervical fusions. The design changes allow for less discomfort due to prominent hardware in thin patients and eliminate the need for an intact medial pubic rami for fixation. There is also no risk of bladder injury due to accidental screw perforation through the pubic rami. The Bridging Infix is ideal for patients who are physiologically too frail for extensive open reduction and plate osteosynthesis, such as elderly patients with pelvic fragility fractures who are failing to mobilise due to pain. It can also be used for patients in whom external fixators may be impractical or poorly tolerated, such as obese patients or those with increased nursing demands. This technique does not provide adequate posterior pelvic ring stability, thus it requires an intact posterior tension band or the addition of separate posterior fixation. Patients can commence in-bed mobilisation the same day as the procedure, with weight-bearing as tolerated allowed for most cases, and toe-touching reserved for highly unstable injury patterns only. The implants are not routinely removed unless requested by the patient, especially in the elderly to avoid additional anaesthetic exposure. Potential complaints include lateral thigh pain, due to lateral femoral nerve compression, and mechanical discomfort during exercise activities. Level of evidence: Level 5

Identification of safe channels for screws in the anterior pelvic ring fixation system

BackgroundMinimally invasive surgery for pelvic fracture using anterior ring internal fixator system is increasing gradually, and the way to insert the fixation screws in the fixation system is the key technical points of the method. However, there have been few studies on insertion of fixation screws for the anterior pelvic ring internal fixator system.ObjectiveTo identify safe channels for fixation screws in the anterior pelvic fixator system and provide the anatomical basis for insertion of fixation screws in clinical operation.MethodsScrew insertion was simulated into a total of 40 pelvic finite element models as well as 16 fresh pelvic specimens, and the channel parameters were measured.ResultsFinite elements (male, female) include: screws in ilium: length 114.4 ± 4.1 and 107.6 ± 8.3 mm, respectively; diameter 11.7 ± 0.5 and 10.0 ± 0.6 mm, distance between screw and anterior inferior iliac spine: 5.5 ± 1.0 and 5.6 ± 1.0 mm, angle of coronal plane 55.8° ± 2.4° and 50.6° ± 3.1°, angle of sagittal plane 26.6° ± 1.0° and 24.5° ± 1.9° and angle of horizontal plane 64.9 ± 3.7 and 58.1 ± 3.1; screws in pubis: length 47.0 ± 2.0 and 39.8 ± 3.9 mm, diameter 7.1 ± 0.4 and 6.1 ± 0.4 mm. Specimens (male, female) include: distance between screw and anterior inferior iliac spine: 5.5 ± 0.5 and 5.6 ± 0.7 mm, angle of coronal plane 55.9° ± 1.3° and 50.7° ± 1.5°, angle of sagittal plane 26.7° ± 0.5° and 24.1° ± 0.9° and angle of horizontal plane 64.8° ± 0.6° and 58.8° ± 0.8°. In the comparison between female and male in each group, differences in distances between screws and anterior inferior iliac spine and median line of symphysis pubis (P > 0.05) were not statistically significant; differences in the remaining parameters were statistically significant (P < 0.05).ConclusionsIf surgeons paid attention to sex differences, select screws of appropriate diameter and length and hold the insertion position and direction, screws in the anterior pelvic ring fixation system could be safely inserted.

Effect analysis of trajectory screw technique in fragility fracture of pelvic ring

To assess the clinical efficacy of minimally invasive technology with trajectory screw fixation for fragility fractures of pelvic(FFP). A retrospective case control study was performed to analyze the clinical data of 35 patients with FFP who were treated and followed up between January 2016 and December 2019. There were 12 males and 23 females, aged from 65 to 99 years with an average of(75.4±7.8) years old. There were 13 cases of type Ⅱb, 7 cases of type Ⅱc, 8 cases of type Ⅲa, 2 cases of type Ⅲb, 2 cases of type Ⅲc, 1 case of type Ⅳb, and 2 cases of type Ⅳc according to Rommens FFP comprehensive classification. All patients received the treatment of minimally invasive technology with trajectory screws fixation. According to the different methods of anterior pelvic ring fixation, FFP patients were divided into two groups:12 cases were fixed with the pedicle screw rod system in the anterior pelvic subcutaneous internal fixator (INFIX) group;23 cases were fixed with hollow screws of the pubic symphysis, superior ramus of pubis or acetabular anterior column in the screw group. The operation time, intraoperative blood loss, intraoperative fluoroscopy times, length of hospital stay, cost of internal fixation, pre- and post-operative visual analogue scale(VAS) were compared between the two groups. The fracture reduction quality was evaluated according to the Matta criteria, and the clinical function was evaluated by the Majeed functional scoring system respectively. All patients were followed up for 12 to 39(16.5±5.4) months after surgery. There was no statistically significant difference in the operation time, intraoperative blood loss, intraoperative fluoroscopy time, and length of hospital stay between the two groups(P>0.05). As for the cost of internal fixation, the cost of internal fixation in the screw group [2 914 (2 914, 4 371) yuan] was significantly lower than that of the INFIX group [6 205 (6 205, 6 205) yuan] (P<0.05). No significant difference was observed in the incidence of postoperative complications between the two groups (P>0.05). There was no significant difference in VAS assessment at admission, 1 week, and 3 months after surgery between the two groups(P>0.05). However, the VAS assessment at 1 week and 3 months after surgery of the two groups were significantly better than those at admission(P<0.05). There was no significant difference in the quality of fracture reduction after the operation and the efficacy evaluation at the last follow-up between the two groups(P>0.05). For the treatment of fragility fractures, minimally invasive technology with trajectory screw fixation can achieve good clinical efficacy. It has the advantages of being relatively minimally invasive, less bleeding, relieving the pain. It deserves clinical application.

Minimally Invasive Surgery for Anterior Pubic Rami Fractures Under Fluoro-Navigation Using the Medtronic O Arm System and Calcium Phosphate for Internal Fixation

Introduction: The incidence of anterior pubic rami fractures in elderly female patients over the age of 65 has been reported to be 64 %. Osteoporosis plays a role with these fractures, as they are caused by minimal low energy injuries from a fall. Indications for internal fixation of anterior pelvic ring are controversial because of the etiology being low energy trauma and the location being a non-weight bearing surface. In contrast to conventional open pelvic surgery, percutaneous screw fixation has gained popularity in the treatment of pelvic fractures, mainly because of minimal soft tissue damage, less operative blood loss, early surgical intervention, and comfortable mobilization of the patient. The use of calcium phosphate as a form of internal fixation further advances the advantages of minimally invasive surgery for internal fixation with less morbidity by the use of screw fixation. The incorporation of fluoro-navigation is a new surgical technique in orthopedic trauma surgery. (Figure 1) This study is to report our clinical results of fluoro-navigation surgery in anterior pelvic pubic rami fractures using calcium phosphate as the fixation of choice. This is the first report of this method of treatment using a new combination of visualization and internal fixation. Materials and Methods: From April 2018 to December 2019, 30 patients with anterior pubic rami fractures were treated with percutaneous cannulated calcium phosphate delivery under Medtronic O arm (fluoro-navigation) control. There were 5 male and 25 females, with a mean age of 84.6 years (range 80-104) for females and mean age of 90 years (84 – 99) for the 5 males. According to the AO and Orthopedic Trauma Association classification, all were considered lateral compression types of fractures. All patients were operated on when their general medical condition stabilized after emergency management and admission. The pain score on admission was reported as 10/10 in all cases. Plain standard pelvic x-rays were obtained on admission as well as CT scans of the pelvis. All the anterior pubic rami fractures were fixed using percutaneous delivery of calcium phosphate with the Zimmer trocar system by one senior surgeon. The Medtronics O arm fluoro-navigation was used in all cases. The surgeon was familiar with the navigation system and had much experience in the computer-assisted percutaneous placement of the trocars. Results: A total of 30 patients were treated with this new combination of surgical treatment of anterior pubic rami fractures. No screws were inserted or found to be necessary for fracture treatment. Each case used 2 trocars from the kits supplied from Zimmer. One end delivery trocar was directed to the inferior pubic ramus fracture and the second which was a side delivery trocar was used for the superior pubic ramus fracture. A total of 10 cc of calcium phosphate was used in each case, 5 cc per trocar. The position of the trocars were placed using the fluoro-navigation control of the O arm. Once the trocars were properly placed the calcium phosphate was delivered and viewed under flouro control and then again viewed with the spin sequence using the Medtronics O arm. Total patient time in the operating room was 56 minutes; Total surgery time was 26 minutes. Anesthesia in most cases was MAC or light sedation with local skin infiltration using 1% lidocaine. Blood loss during the operation was considered very minimal with derma bond used to cover the percutaneous sites as well as a small band-aid. No superficial or deep infections occurred. No patient sustained recognized neurologic, vascular, or urologic injury because of the percutaneous pubic rami fixation with calcium phosphate. Extravasation of the calcium phosphate from the fracture’s sites did not pose any sequelae with soft tissue injury or with fracture healing. All patients were encouraged to get out of bed and weight bear according to comfort on post-op day 1. All fractures united at the last follow-up. Conclusions: This study presented for the first time two new techniques for the operative treatment of pubic rami fractures of the pelvis. The delivery of calcium phosphate for fracture fixation of pubic rami fractures has been found to be safe, minimally invasive, providing pain relief and stability permitting early mobilization. The addition of intra-operative fluoro- navigation technique makes the fracture treatment an accurate, and rapid method for the treatment of pubic rami fractures. Consistency of the operative procedure and teaching are mandatory for the success of this procedure. The learning curve for most orthopedists should be very short. The outcomes have been shown to benefit patient mobilization, decrease morbidity and decrease hospital stay

Similar patient reported outcomes at long-term follow-up after external fixation versus internal fixation of the anterior ring component of APC injuries

Purpose: Unstable pelvic ring injuries produced by external rotation of the hemipelvis and a symphyseal disruption are most often treated with internal fixation of the anterior ring, with percutaneous treatment of the posterior ring as needed. In some clinical situations, patients are treated with external fixation for their anterior injuries and the long-term functional outcomes associated with external fixation are not well understood. We ask if there is a difference in functional outcome, between treatment of these injuries with internal versus external fixation, when measured at a minimum of three years after injury.Method: This was a retrospective cohort study performed at a level one regional trauma center. Trauma database review identified 128 patients, with 70 subsequently excluded, with unstable anterior posterior compression (APC) pelvic ring injuries (OTA 61B2.3 & 61C1.2) treated with surgery with minimum three years of follow-up. An intervention of internal fixation versus external fixation of anterior pelvic ring was performed, and depending on the injury, supplemented with posterior iliosacral screw fixation. Main outcome was measured with the Majeed functional outcome score (0-100).Results: Patients treated with external fixation reported a Majeed score of 70 (95% CI 28-100) compared to 79 (95% CI 36-100) in those with internal fixation (p-value 0.28). Subgroups of the Majeed score were not significantly different (p value > 0.05). Open fractures, severity of injury, and ISS were worse in those treated with external fixation. There was no differential loss to follow-up.Conclusion Patients with unstable pelvic ring injuries with symphyseal disruptions treated with external fixation as definitive treatment versus internal fixation may fare no different in the long term.

Feasibility of anterior pelvic ring fixation alone for treating lateral compression type 1 pelvic fractures with nondisplaced complete sacral fractures: a retrospective study.

PurposeThe aim of this study was to evaluate the feasibility of anterior pelvic ring fixation alone for treating lateral compression type 1 (LC-1) fractures with nondisplaced complete sacral fractures.MethodsPatients with LC-1 type pelvic fractures with nondisplaced complete sacral fractures in the Xi’an Honghui Hospital were screened. Those who underwent surgical treatment for the anterior pelvic ring fractures and conservative treatment for the sacral factures were included in the analysis. The Majeed and Short Form-12 (SF-12) functional scores were used to evaluate these patients.ResultsOf the 123 patients enrolled, 108 (88%) responded to our enquiries regarding the outcome. The mean follow-up period was 18.37 months for the 108 patients who responded. The mean SF-12 functional score was 48.22 ± 9.68. The mean Majeed score was 83.47 ± 9.23, including 52 with excellent, 47 with good, seven with fair, two with poor outcomes. The SF-12 functional and Majeed scores were significantly higher in those aged <45 years or without lower limb injury than in those aged ≥45 years or with lower limb injury (P < 0.05).ConclusionAcceptable functional outcomes can be obtained for LC-1 pelvic fractures with nondisplaced complete sacral fractures by using anterior pelvic ring fixation alone.

Preperitoneal Pelvic Packing Is Not Associated With an Increased Risk of Surgical Site Infections After Internal Anterior Pelvic Ring Fixation.

To investigate the risk of postoperative surgical site infections after plate fixation of the anterior pelvic ring subsequent to preperitoneal pelvic packing (PPP). Retrospective observational cohort study. Level I academic trauma center. Adult trauma patients with unstable pelvic ring injuries requiring surgical fixation of the anterior pelvic ring. Pelvic plate fixation was performed as a staged procedure after external fixation and PPP/depacking (PPP group; n = 25) or as a single-stage primary internal fixation (control group; n = 87). Incidence of postoperative surgical site infections of the pelvic space. Anterior pelvic plate fixation was performed in 112 patients during a 5-year study period. The PPP group had higher injury severity scores and transfused packed red blood cells than the control group (injury severity score: 46 ± 12.2 vs. 29 ± 1.5; packed red blood cells: 13 ± 10 vs. 5 ± 2; P < 0.05). The mean time until pelvic depacking was 1.7 ± 0.6 days (range: 1-3 days) and 3.4 ± 3.7 days (range: 0-15 days) from depacking until pelvic fracture fixation. Two patients in the PPP group and 8 patients in the control group developed a postoperative infection requiring a surgical revision (8.0% vs. 9.2%; n.s.). Both PPP patients with a pelvic space infection had undergone anterior plate fixation for associated acetabular fractures. These data support the safety of the PPP protocol for bleeding pelvic ring injuries due to the lack of increased infection rates after fracture fixation. Caution should be applied when considering PPP in patients with associated acetabular fractures. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Are two retrograde 3.5 mm screws superior to one 7.3 mm screw for anterior pelvic ring fixation in bones with low bone mineral density?

ObjectivesOsteosynthesis of anterior pubic ramus fractures using one large-diameter screw can be challenging in terms of both surgical procedure and fixation stability. Small-fragment screws have the advantage of following the pelvic cortex and being more flexible.The aim of the present study was to biomechanically compare retrograde intramedullary fixation of the superior pubic ramus using either one large- or two small-diameter screws.Materials and MethodsA total of 12 human cadaveric hemipelvises were analysed in a matched pair study design. Bone mineral density of the specimens was 68 mgHA/cm3 (standard deviation (sd) 52). The anterior pelvic ring fracture was fixed with either one 7.3 mm cannulated screw (Group 1) or two 3.5 mm pelvic cortex screws (Group 2). Progressively increasing cyclic axial loading was applied through the acetabulum. Relative movements in terms of interfragmentary displacement and gap angle at the fracture site were evaluated by means of optical movement tracking. The Wilcoxon signed-rank test was applied to identify significant differences between the groupsResultsInitial axial construct stiffness was not significantly different between the groups (p = 0.463). Interfragmentary displacement and gap angle at the fracture site were also not statistically significantly different between the groups throughout the evaluated cycles (p ⩾ 0.249). Similarly, cycles to failure were not statistically different between Group 1 (8438, sd 6968) and Group 2 (10 213, sd 10 334), p = 0.379. Failure mode in both groups was characterised by screw cutting through the cancellous bone.ConclusionFrom a biomechanical point of view, pubic ramus stabilisation with either one large or two small fragment screw osteosynthesis is comparable in osteoporotic bone. However, the two-screw fixation technique is less demanding as the smaller screws deflect at the cortical margins.Cite this article: Y. P. Acklin, I. Zderic, S. Grechenig, R. G. Richards, P. Schmitz, B. Gueorguiev. Are two retrograde 3.5 mm screws superior to one 7.3 mm screw for anterior pelvic ring fixation in bones with low bone mineral density? Bone Joint Res 2017;6:8–13. DOI: 10.1302/2046-3758.61.BJR-2016-0261.

Minimally invasive surgery under fluoro-navigation for anterior pelvic ring fractures.

Background:The incidence of pelvic fractures in trauma patients is reported to be 3–8.2%, with roughly half of these fractures being caused by high energy injuries with a potential for catastrophic hemorrhage and death. Indications for internal fixation of anterior pelvic ring are controversial. Because of fears of disturbing the pelvic hematoma and causing additional hemorrhage, open reduction and internal fixation of pelvic ring disruption is routinely delayed. In contrast to conventional surgery, percutaneous screw fixation is gaining popularity in the treatment of pelvic and acetabular fractures mainly because of minimal soft tissue damage, less operative blood loss, early surgical intervention and comfortable mobilization of the patient. Fluoro-navigation is a new surgical technique in orthopedic trauma surgery. This study is to investigate clinical results of fluoro-navigation surgery in anterior pelvic ring fractures.Materials and Methods:From January 2006 to October 2011, 23 patients with anterior pelvic ring fractures were treated with percutaneous cannulated screw under fluoro-navigation. There were 14 men and 9 women, with a mean age of 40.1 years (range 25–55). According to the AO and Orthopedic Trauma Association classification, there were seven A 2.1, two A 2.2, one A 2.3, six B 1.2, one B 2.1: 1, one B 2.2, one C 1.2, two C 1.3 and two C 2.3 types of fractures. Amongst these patients, 13 had posterior pelvic ring injuries, 8 had other injuries including urethral, lumbar vertebrae fractures and femoral fractures. All patients were operated when their general condition stabilized after emergency management. The mean time from injury to percutaneous screw fixation of the anterior pelvic ring fracture was 12 days (3–15 days). All the anterior ring fractures were fixed with cannulated screws by two senior surgeons. They were familiar with the navigation system and had gained much experience in the computer-assisted percutaneous placement of screws.Results:A total of 32 screws were inserted, including 19 in the pubic ramis and 13 in the anterior acetabular columns. The average surgical time was 23.3 min/screw. The average time of X-ray exposure was 19.1 ± 2.5 s/screw. The virtual images of fluoro-navigation were compared with real-time X-rays during and after the surgery. Compared to the final position of the screw, the average deviated distance was 3.11 mm and the average trajectory difference was 2.81°. Blood loss during the operation was minimal (22.3 ml/screw). One screw (3.1%) deviated out of the fracture site during the operation. No superficial or deep infection occurred. No patient sustained recognized neurologic, vascular, or urologic injury as a result of the percutaneous screw fixation. All fractures united at the last followup.Conclusions:Fluoro-navigation technique could become a safe, accurate, and fairly quick method for the treatment of anterior pelvic ring fractures. Standardization of the operative procedure and training are mandatory for the success of this procedure.