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Background
Floating pubic symphysis (FPS) is a relatively rare injury caused by high-energy mechanisms. There are several fixation methods used to treat FPS, including external fixation, subcutaneous fixation, internal fixation, and percutaneous cannulated screw fixation. To choose the appropriate fixation, it is necessary to study the biomechanica...
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Citations
... Biomechanical studies play a critical role in determining the load capacity of different fixation methods for pelvic injury by evaluating the stability of external fixators in preclinical experimental trials or by computational modelling, considering various factors that may influence the stability of the construct (Gardner et al., 2012b;Song et al., 2017). These studies provide valuable data on pin placement and frame strength, increasing the potential of external fixators to provide optimal stability (Noordeen et al., 1993;Kim et al., 1999). ...
... Four papers examined 103 specimens computationally. Therefore, Shan et al. used computer tomography models of one hundred patients (Shan et al., 2021), while three computational papers studied only one model each (García et al., 2000;Ali et al., 2014;Song et al., 2017), and one study investigated eight patients and one computational model (Liang et al., 2020). In the computational studies, sex distribution was kept balanced. ...
... Device type and configuration, pin size, and geometry varied between but also within the different types of injury. Two different fixators were tested for type A injury: Supra-acetabular fixed pins with two 5 mm pins per side (Song et al., 2017), or pins fixed to the iliac crest (Gunterberg et al., 1978). For type B injury, three different fixators were tested trialled on the AIIS (anterior inferior iliac spine) with two pins per side and 5 or 6 mm in thickness (Pohlemann et al., 1994;Kim et al., 1999;García et al., 2000). ...
... Auch sollte über ein posttraumatisches Arthroserisiko aufgeklärt werden (32). Allen therapeutischen Vor-gehensweisen ist folglich das Ziel einer Minimierung der Ruhigstellung von maximal fünf bis sechs Wochen und Sicherstellung einer frühzeitigen Mobilisierung zur Wiederherstellung der Funktionalität gemein (3,26,(33)(34)(35). ...
Background:
Fractures of the fingers and metacarpal bones are the most common fracture type in the upper limb, with an incidence of 114 to 1483 per 100 000 persons per year. The clinical importance of closed finger and metacarpal fractures is often underestimated; inadequate diagnostic and therapeutic measures may result in serious harm. This review concerns the basic elements of the diagnosis and treatment of finger and metacarpal fractures.
Methods:
This review of the incidence, diagnosis and treatment of finger and metacarpal fractures is based on pertinent publications retrieved by a selective search of the literature.
Results:
The main focus of treatment lies on restoration of hand function in consideration of the requirements of the individual patient. The currently available evidence provides little guidance to optimal treatment (level II evidence). Although most closed fractures can be managed conservatively, individualized surgical treatment is advisable in comminuted fractures and fractures with a relevant degree of torsional malposition, axis deviation, or shortening, as well as in intra-articular fractures. Minimally invasive techniques are, in principle, to be performed wherever possible, yet open surgery is sometimes needed because of fracture morphology. Postsurgical complication rates are in the range of 32-36%, with joint fusion accounting for 67-76% of the complications. 15% involve delayed fracture healing and pseudarthrosis.
Conclusion:
Individualized treatment for finger and metacarpal fractures can improve patients' outcomes, with major socio-economic and societal benefits. Further high-quality studies evaluating the relative merits of the available treatments are needed as a guide to optimized therapy.
... Disruption of the pubic symphysis exceeding 25 mm is believed to be an absolute indication for operative intervention [5]. Several fixation strategies are used to enhance the stability of the anterior pelvic ring, such as external, internal, percutaneous, and subcutaneous fixation devices [6,[11][12][13][14][15][16][17]. Internal fixation of the anterior plate combined with posterior percutaneous cannulated screws is the preferred method to treat PSD, considering that 54-97% of anterior pelvic ring fractures are associated with posterior pelvic ring injuries [18][19][20]. ...
... The authors found that the novel device was a safe, efficient, and simple technique to treat PSD because of the biomechanical advantages of strengthened fixation to the inferior symphysis. Subcutaneous fixation systems with plates or pedicle screw-rod devices were introduced to fix anterior pelvic ring injuries [12,15,16]. The subcutaneous technique could provide sufficient biomechanical stability with fewer surgical complications, particularly for patients with hemodynamic instability or diabetes mellitus [21,22]. ...
... The connect type of springs was set as connect two points based on anatomical attachment points of ligaments. The material properties of the finite element models [12,13] are shown in Table 1. ...
Abstract Background Pubic symphysis diastasis (PSD) hinders the connection between bilateral ischia and pubic bones, resulting in instability of the anterior pelvic ring. PSD exceeding 25 mm is considered disruptions of the symphyseal and unilateral/bilateral anterior sacroiliac ligaments and require surgical intervention. The correct choice of fixation devices is of great significance to treat PSD. This study aimed to evaluate the construct stability and implant performance of seven fixation methods to treat PSD using finite element analysis. Methods The intact skeleton-ligament pelvic models were set as the control group. PSD models were simulated by removing relevant ligaments. To enhance the stability of the posterior pelvic ring, a cannulated screw was applied in the PSD models. Next, seven anterior fixation devices were installed on the PSD models according to standard surgical procedures, including single plates (single-Plate group), single plates with trans-symphyseal cross-screws (single-crsPlate group), dual plates (dual-Plate group), single cannulated screws, dual crossed cannulated screws (dual-canScrew group), subcutaneous plates (sub-Plate group), and subcutaneous pedicle screw-rod devices (sub-PedRod group). Compression and torsion were applied to all models. The construct stiffness, symphyseal relative micromotions, and von Mises stress performance were recorded and analyzed. Results The construct stiffness decreased dramatically under PSD conditions. The dual-canScrew (154.3 ± 9.3 N/mm), sub-Plate (147.1 ± 10.2 N/mm), and sub-PedRod (133.8 ± 8.0 N/mm) groups showed better ability to restore intact stability than the other groups (p
... The FEA results of the present study show that the displacement distribution and vM stress were similar in the MPSRF and INFIX models compared to the intact model, indicating that both fixation techniques can effectively treat anterior pelvic ring fractures. Song et al. reported that the maximum von Mises stress appeared at the rod-screw and screw-bone interfaces in floating public symphysis by finite element analysis, which is basically consistent with our result analysis [22]. However, the maximum displacements of the pelvis and implant were lower in the modified group than in the conventional group in the single-(left/right) and dualleg standing and sitting postures, indicating greater stability. ...
Objectives
This study compared the stability and clinical outcomes of modified pedicle screw-rod fixation (MPSRF) and anterior subcutaneous internal pelvic fixation (INFIX) for the treatment of anterior pelvic ring fractures using the Tornetta and Matta grading system and finite element analyses (FEA).
Methods
In a retrospective review of a consecutive patient series, 63 patients with Orthopaedic Trauma Association (OTA)/Arbeitsgemeinschaft für Osteosynthesefragen (AO) type B or C pelvic ring fractures were treated by MPRSF ( n = 30) or INFIX ( n = 33). The main outcome measures were the Majeed score, incidence of complications, and adverse outcomes, and fixation stability as evaluated by finite element analysis.
Results
Sixty-three patients were included in the study, with an average age of 34.4 and 36.2 in modified group and conventional group, respectively. Two groups did not differ in terms of the injury severity score, OTA classification, cause of injury, and time to pelvic surgery. However, the MPSRF group had a rate of higher satisfactory results according to the Tornetta and Matta grading system than the conventional group (73.33% vs 63.63%) as well as a higher Majeed score (81.5 ± 10.4 vs 76.3 ± 11.2), and these differences were statistically significant at 6 months post-surgery. FEA showed that MPSRF was stiffer and more stable than INFIX and had a lower risk of implant failure.
Conclusions
Both MPSRF and INFIX provide acceptable biomechanical stability for the treatment of unstable anterior pelvic ring fractures. However, MPSRF provides better fixation stability and a lower risk of implant failure, and can thus lead to better clinical outcomes. Therefore, MPSRF should be more widely applied to anterior pelvic ring fractures
... Anterior ring injuries may be caused by different mechanisms and can occur through the pubic symphysis, the pubic rami, or both [5]. Furthermore, pubic rami fractures may include one, two, three, or four pubic rami; the latter corresponding to a floating pubic symphysis, which is a severe, unstable injury [6]. Classically, external fixation has been used in an emergency setting, anterior supra-acetabular external fixator (ASAEF) being the location of choice for the temporary stabilisation of mechanically unstable fractures [3]. ...
PurposeManagement of anterior ring injuries is still a matter of discussion, and there are only few studies reporting anterior external fixator as definitive treatment for unstable pelvic injuries. This study aimed to describe the clinical and radiological outcomes of a consecutive series of mechanically unstable pelvic injuries that were treated with definitive anterior supra-acetabular external fixator for the anterior ring, and to identify risk factors for failure.Methods
We included a consecutive series of patients with unstable pelvic ring fractures who underwent anterior supra-acetabular external fixation for definitive treatment, between January 2012 and January 2020. All demographics, associated injuries and procedures, injury mechanism, and complications were analysed. Pelvic fracture was classified based on Orthopaedic Trauma Association/Tile AO (OTA/AO) and Young–Burgess classifications. Complications associated with the external fixator were revised. All patients were functionally evaluated at final follow-up and asked to report their clinical outcomes using the Majeed score.ResultsA total of 47 patients were included, of which 25 were females. The median age was 44 years (interquartile range 23–59). Median follow-up duration was 14 months (interquartile range 6–31). The most frequent aetiology was motor vehicle accident (35), followed by fall from height (8). All fractures required posterior pelvic ring fixation. The median time during which patients had external fixation in situ was 11 weeks (interquartile range 9–13). All patients achieved healing of pelvic fracture at median time of 10 weeks (interquartile range 8–12). At final follow-up, the median displacement of the anterior pelvis was 6 mm (interquartile range 0–11). Superficial infection was the most common complication (n = 7). No washout procedures were needed. No major complication was reported. No patient required reoperation for anterior ring fracture. The median Majeed score was 88 points (range 60–95; interquartile range 80–90) at final follow-up.Conclusion
Our findings suggest that the use of supra-acetabular external fixator is safe and effective for definitive treatment of the anterior ring in unstable pelvic fractures. It is a method with high proportion of excellent results, regardless of the type of fracture. The rate of complications is low, and it does not compromise functional results.
... [23][24][25] Comparisons of the fixation strength between the reconstruction plate and the cannulated screw are inconsistent in different mechanical studies. [26][27][28][29] On the contrary, in clinical reports, the failure rates of these 2 fixations were similar and much lower compared to other types of fixation, [9][10][11][15][16][17]30,31] which indicate that both could treat anterior pelvic ring injuries reliably and effectively. ...
The aim of this study is to explore the clinical outcome and indications in treating anterior ring injury of Tile C pelvic fracture with minimally invasive internal fixation.
We retrospectively reviewed 18 patients (aged 25–62, 34.2 ± 7.4) with 26 pelvic anterior ring injuries of Tile C pelvic fracture treated with minimally invasive internal fixation in our hospital were from January 2012 to August 2016. Two cases were pubic symphysis diastasis, 15 were anterior ring fracture (7 were bilateral), and 1 was vertical displacement of pubic symphysis associated with pubic ramus fracture. According to Tile classification, 8, 4, and 6 cases were types C1, C2, and C3, respectively. All patients accepted the operation of pelvic fractures on both rings, while the anterior ring injuries were treated with minimally invasive internal fixation. The period from injury to operation was 5 to 32 days (11.2 ± 3.7). Four patients had pubic symphysis diastasis or pelvic anterior ring fracture medial obturator foramen reduced with modified Pfannenstiel incision and fixed with cannulated screws, 14 patients (22 fractures) had a fractured lateral obturator foramen reduced with modified Pfannenstiel incision associated with small iliac crest incision and fixed with locking reconstruction plates. Clinical data, such as operation time, intraoperative bleeding, Matta standard to assess the reduction quality of fracture, and complications, were collected and analyzed.
The operation time ranged from 30 to 65 minutes (42.8 ± 18.7), and the intraoperative bleeding volume was 30 to 150 mL (66.5 ± 22.8). All cases were continuously followed-up for 16 to 42 months (30.2 ± 4.6). All fractures were healed between 3 and 9 months postoperatively (4.9 ± 2.7 months). According to the Matta standard assessment, 18, 7, and 1 cases were excellent, good, and fair, respectively, with a 96.2% (25/26) rate of satisfaction. Neither reduction loss, fixation failure, nor infection occurred; complications included 1 patient with fatal liquefaction, 1 patient had lateral femoral cutaneous nerve injury, and 1 patient complained of discomfort in the inguinal area due to fixation stimulation.
Minimally invasive internal fixation for pelvic anterior ring injury in Tile C pelvic fracture has the advantages of less damage, safer manipulation, less complications, and good prognosis.
... The INFIX also seems more effective than external fixation at reducing postoperative surgical site pain [16]. Other disadvantages of the external pelvic fixator include worse outcomes in diabetic and obese patients [17]. ...
... The symphysis-fixed INFIX (extended unilateral INFIX) could provide improved rotational stability compared to the bilateral INFIX with fixation of the symphysis. A finite element study by Song et al. [17] showed better rotational stability of the plate fixation fixed to the symphysis compared to the bilateral INFIX. It was concluded that this could be due to the fixation to the symphysis [17]. ...
... A finite element study by Song et al. [17] showed better rotational stability of the plate fixation fixed to the symphysis compared to the bilateral INFIX. It was concluded that this could be due to the fixation to the symphysis [17]. ...
Background
Operative procedures for unstable pelvic ring fractures remain controversially discussed. Minimally invasive treatment options for pelvic ring fractures have several benefits for the patient. But they can also provide disadvantages. Anterior subcutaneous pelvic fixation (INFIX) has shown promising biomechanical results in pelvic ring fractures, but there is a high complication rate of nerve injuries. An additional screw to the INFIX seems to be more stable. The aim of this study is to compare biomechanical stability of a new modified unilateral INFIX fixing the unilateral injured pelvic ring with the standard INFIX.
Methods
24 composite synthetic full pelvises were used in this study. 4 groups each with a number of six pelvic specimens were randomly assigned. A C1.3-type pelvic fracture was made with an osteotomy of the sacrum and an osteotomy of the anterior pelvic ring. Fracture fixation was performed within the four groups: (1) unilateral INFIX, (2) “extended” unilateral INFIX + additional pubic ramus pedicle screw, (3) bilateral INFIX, (4) “extended” bilateral INFIX + additional pubic ramus pedicle screw. All specimens were cyclic loaded with 200 N until maximum of 300 N. Distance/dislocation of the fracture fragments were detected with 3D-ultrasound measuring system. Stiffness was calculated.
Results
Extended unilateral INFIX showed the lowest mean dislocation. Lowest rotational stability was displayed by the standard bilateral INFIX. A significant difference (P = 0.04) was shown between the extended unilateral INFIX and the “standard” bilateral INFIX in terms of rotational stability. Extended unilateral INFIX showed significantly improved stability of anterior fracture dislocation (P = 0.01) and unilateral INFIX showed the highest rotational stiffness. Anterior fixation stiffness of the unilateral INFIX was significantly improved using an additional symphysis/pubic ramus screw (P = 0.002).
Conclusion
Extended unilateral INFIX (+ additional pubic ramus pedicle screw) is a feasible minimally invasive treatment for anterior pelvic ring fractures. Higher stability and lower probability of bilateral nerve damage is provided by the extended unilateral INFIX compared to the standard bilateral INFIX.
For robot-assisted pelvic fracture reduction, at least two bone needles need to be inserted into the ilium of the affected pelvis, and the robot clamping device is connected with the bone needles. The biomechanical properties of the pelvic musculoskeletal tissues are different with the different Spatial Position and Orientation (SPO) of the bone needles. In order to determine the optimal SPO of bone needle pairs, the constraints between the bone needles and the pelvis are analyzed, and the SPO vectors of 150 groups bone needles are obtained by the KNN-hierarchical clustering method; a batch modeling method of bone needles with different SPO is proposed. 150 finite element models of damaged pelvic musculoskeletal tissue with different SPO of bone needles are established and simulated. The stress and strain distribution homogenization of musculoskeletal tissue with bone needles as evaluation index, the simulation results of 150 models are evaluated. Results show that, the anterior superior iliac spine and the anterior inferior iliac spine are suitable regions to place bone needles in the pelvis, and the optimal distribution of the needle combination is found in this region. The overall stress and strain distribution of the damaged pelvic musculoskeletal tissue under the large reduction force is the best.
Aims:
The best method of treating unstable pelvic fractures that involve the obturator ring is still a matter for debate. This study compared three methods of treatment: nonoperative, isolated posterior fixation and combined anteroposterior stabilization.
Patients and methods:
The study used data from the German Pelvic Trauma Registry and compared patients undergoing conservative management (n = 2394), surgical treatment (n = 1345) and transpubic surgery, including posterior stabilization (n = 730) with isolated posterior osteosynthesis (n = 405) in non-complex Type B and C fractures that only involved the obturator ring anteriorly. Calculated odds ratios were adjusted for potential confounders. Outcome criteria were intraoperative and general short-term complications, the incidence of nerve injuries, and mortality.
Results:
Operative stabilization reduced mortality by 36% (odds ratio (OR) 0.64, 95% confidence interval (CI) 0.42 to 0.98) but the incidence of complications was twice as high (OR 2.04, 95% CI 1.57 to 2.64). Mortality and the incidence of neurological deficits at discharge were no different after isolated posterior or combined anteroposterior fixation. However, the odds of both surgical (98%, OR 1.98, 95%CI 1.22 to 3.22) and general complications (43%, OR 1.43, 95% CI 1.02 to 2.00) were higher in the group with the more extensive surgery.
Conclusion:
Operative stabilization is recommended for non-complex unstable pelvic fractures. The need for anterior fixation of obturator ring fractures should, however, be considered critically. Cite this article: Bone Joint J 2018;100-B:973-83.
