Patient-related outcome of unstable pelvic ring fractures stabilized with a minimal invasive screw-rod system

Pelvic Ring Fractures: A Biomechanical Comparison of Sacral and Lumbopelvic Fixation Techniques

BACKGROUND CONTEXT

Pelvic ring fractures are becoming more common in the aging population and can prove to be fatal, having mortality rates between 10% and 16%. Stabilization of these fractures is challenging and often require immediate internal fixation. Therefore, it is necessary to have a biomechanical understanding of the different fixation techniques for pelvic ring fractures.

METHODS

A previously validated three-dimensional finite element model of the lumbar spine, pelvis, and femur was used for this study. A unilateral pelvic ring fracture was simulated by resecting the left side of the sacrum and pelvis. Five different fixation techniques were used to stabilize the fracture. A compressive follower load and pure moment was applied to compare different biomechanical parameters including range of motion (contralateral sacroiliac joint, L1-S1 segment, L5-S1 segment), and stresses (L5-S1 nucleus stresses, instrument stresses) between different fixation techniques.

RESULTS

Trans-iliac-trans-sacral screw fixation at S1 and S2 showed the highest stabilization for horizontal and vertical displacement at the sacral fracture site and reduction of contralateral sacroiliac joint for bending and flexion range of motion by 165% and 121%, respectively. DTSF (Double transiliac rod and screw fixation) model showed highest stabilization in horizontal displacement at the pubic rami fracture site, while the L5_PF_W_CC (L5-Ilium posterior screw fixation with cross connectors) and L5_PF_WO_CC (L5-Ilium posterior screw fixation without cross connectors) showed higher rod stresses, reduced L1-S1 (approximately 28%), and L5-S1 (approximately 90%) range of motion.

CONCLUSIONS

Longer sacral screw fixations were superior in stabilizing sacral and contralateral sacroiliac joint range of motion. Lumbopelvic fixations displayed a higher degree of stabilization in the horizontal displacement compared to vertical displacement of pubic rami fracture, while also indicating the highest rod stresses. When determining the surgical approach for pelvic ring fractures, patient-specific factors should be accounted for to weigh the advantages and disadvantages for each technique.

Effectiveness of permissive weight bearing in surgically treated trauma patients with peri- and intra-articular fractures of the lower extremities: a prospective comparative multicenter cohort study

PURPOSE

The aim of the present study was to investigate the effectiveness of a novel approach involving permissive weight bearing (PWB) in surgically treated trauma patients with peri- and intra-articular fractures of the lower extremities.

METHODS

Prospective comparative multicenter cohort study in one level 1 trauma center and five level 2 trauma centers. Surgically treated trauma patients with peri- and intra-articular fractures of the lower extremities were included. Permissive weight bearing (PWB) in comparison to restricted weight bearing (RWB) was assessed over a 26-week post-surgery follow-up period. Patients' self-perceived outcome levels regarding activities of daily living (ADL), quality of life (QoL), pain and weight bearing compliance were used.

RESULTS

This study included 106 trauma patients (N = 53 in both the PWB and RWB groups). Significantly better ADL and QoL were found in the PWB group compared to the RWB group at 2-, 6-, 12- and 26-weeks post-surgery. There were no significant differences in postoperative complication rates between the PWB and RWB groups.

CONCLUSION

PWB is effective and is associated with a significantly reduced time to full weight bearing, and a significantly better outcome regarding ADL and QoL compared to patients who followed RWB regimen. Moreover, no significant differences in complication rates were found between the PWB and RWB groups.

LEVEL OF EVIDENCE

Level II.

REGISTRATION

This study is registered in the Dutch Trial Register (NTR6077). Date of registration: 01-09-2016.

Work Productivity Loss After Minimally Displaced Complete Lateral Compression Pelvis Fractures

OBJECTIVE

To quantify work impairment and economic losses due to lost employment, lost work time (absenteeism), and lost productivity while working (presenteeism) after a lateral compression pelvic ring fracture. Secondarily, productivity loss of patients treated with surgical fixation versus nonoperative management was compared.

METHODS

DESIGN

Secondary analysis of a prospective, multicenter trial.

SETTING

Two level I academic trauma centers.

PATIENT SELECTION CRITERIA

Adult patients with a lateral compression pelvic fracture (OTA/AO 61-B1/B2) with a complete posterior pelvic ring fracture and less than 10 mm of initial displacement. Excluded were patients who were not working or non-ambulatory before their pelvis fracture or who had a concomitant spinal cord injury.

OUTCOME MEASURES AND COMPARISONS

Work impairment, including hours lost to unemployment, absenteeism, and presenteeism, measured by Work Productivity and Activity Impairment assessments in the year after injury. Results after non-operative and operative treatment were compared.

RESULTS

Of the 64 included patients, forty-seven percent (30/64) were treated with surgical fixation, and 53% (30/64) with nonoperative management. 63% returned to work within 1 year of injury. Workers lost an average of 67% of a 2080-hour average work year, corresponding with $56,276 in lost economic productivity. Of the 1395 total hours lost, 87% was due to unemployment, 3% to absenteeism, and 10% to presenteeism. Surgical fixation was associated with 27% fewer lost hours (1155 vs. 1583, P = 0.005) and prevented $17,266 in average lost economic productivity per patient compared with nonoperative management.

CONCLUSIONS

Lateral compression pelvic fractures are associated with a substantial economic impact on patients and society. Surgical fixation reduces work impairment and the corresponding economic burden.

LEVEL OF EVIDENCE

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

Bony Sacral Volume after Sacro-Iliac Screw Fixation of Pelvic Fractures Is Dependent on Reduction of the Anterior Pelvic Ring

Pelvic ring injuries are uncommon but serious injuries. Percutaneous sacro-iliac screw fixation (SSF) is the standard treatment for posterior stabilization of pelvic fractures. Compression forces of the SSF might cause deformity of the sacrum and the pelvic ring. The aim of this radio-volumetric study is to evaluate the morphometry of the sacrum and pelvic ring in SSF for posterior pelvic fractures. (1) Methods: We conducted a radio-volumetric study measuring the bony sacral volume before and after SSF for a pelvic fracture based on a three-dimensional reconstruction of the pre- and postoperative computed tomography scan of 19 patients with a C-type pelvic fracture. In addition to the bony sacral volume, we assessed the pelvic deformity and the load bearing axis. We compared the results of patients without anterior stabilization (Group A) to patients who had additional ORIF of the anterior pelvic ring. (2) Results: Median age of the patients was 41.2 years (±17.8). All patients received percutaneous SSF with partially threaded 7.3 mm screws. The sacral volume decreased from 202.9 to 194.3 cm³ in group A (non-operative treatment anterior, n = 10) and an increase of sacral volume from 229.8 to 250.4 cm³ in group B (anterior ORIF; n = 9). Evaluation of the pelvic deformity also reflected this trend by a decrease of the ipsilateral load-bearing angle in group A (37.0° to 36.4°) and an increase of this angle in group B (36.3 to 39.9°). (3) Conclusions: Bony sacral volume and pelvic deformity after sacro-iliac screw fixation in pelvic fractures depend on treatment of the anterior pelvic ring. Reduction and fixation of the anterior fracture shows an increase of the bony sacral volume and the load bearing angle leading to a closer to normal reconstruction of the pelvic anatomy.

Imaging, post-processing and navigation: Surgical applications in pelvic fracture treatment

Technical advancements of the past decade have led to massive improvements regarding imaging and visualization in trauma care. Digital imaging technology has fundamentally changed most processes in fracture management. However, the digital revolution in trauma surgery has just begun. Optical tracking navigation is currently the gold standard for positioning of implants for advanced applications in trauma surgery. Digital technology may enable the surgeon to achieve the same level of safety even in non-navigated placement of screws: We developed a new planning tool to transcript a preoperative into a semi-transparent "fluoroscopic like" image that can be identified intraoperatively and used as a map for the safe placement of sacro-iliac screws based on the "vestibule concept". In the future, development of artificial intelligence algorithms may provide features like automated segmentation of bone-fragments and other applications for a systematic fracture analysis to improve the standard of care in trauma surgery. Digital transformation has massive impact on diagnostics and surgical management of pelvic fractures. Improved visualization technology provides a better understanding of the surgical anatomy of the pelvis and may enable the surgeon to achieve greatest safety in percutaneous placement of screws even without using optical tracking navigation tools. The "para-axial fusion technique" is a useful tool to plan fluoroscopic views based on a 3D dataset prior to the surgery.

Substantation of the method of lumbo-pelvic fixation in verically unstable fractures of the sacrum

Background. According to the literature and our own observations, there is an increase in the number of victims of young, able-bodied age with severe injuries to the pelvic structures. Despite numerous developments and studies in this area, high mortality and a high percentage of unsatisfactory treatment results remain. The publication reflects the advantages of using bilateral lumbopelvic fixation in the treatment of injuries to the cross. Load calculation, biomechanical modeling of damages and displacing factors are presented. Bilateral lumbopelvic fixation has proven to be a reliable method capable of providing reliable fixation of the fracture at all stages of treatment. Aim. To substantiate and test modified lumbopelvic stabilization of the pelvic ring in patients with vertically unstable (C1-2-3 according to Tile M.) sacral fractures. Material and methods. Based on the treatment of 20 patients with severe sacral fractures, it was proved that the best result was achieved with bilateral lumbopelvic stabilization. The use of the author's version (RF Patent No. 2684870 "Method of fixation in unilateral unstable sacral fractures") of osteosynthesis is presented on the example of the treatment of multiple pelvic trauma, a good clinical result was obtained, and neurological symptoms were stopped. Results. Lumbar-iliac osteosynthesis for vertically unstable sacral fractures is the optimal method of fixation. The distribution vector of the levers of the latch corresponds to the biasing force, which ensures maximum reliability of the synthesis. The method, if necessary, creates conditions for decompression of the roots, prevents the early development of arthrosis of the sacroiliac joints. Using it allows you to maintain or correct the sagittal and frontal balance of the spine. The use of bilateral 8-screw lumboiliac fixation with the installation of a transverse tie is recommended, since unilateral fixation or a decrease in the number of fixing elements can lead to loosening of the fixator. Conclusion. Based on biomechanical modeling and the results of treatment of patients with severe injuries of the posterior pelvic ring, the effectiveness of the proposed method of lumbopelvic fixation was proven.

Clinical and Patient-Related Outcome After Stabilization of Dorsal Pelvic Ring Fractures: A Retrospective Study Comparing Transiliac Fixator (TIFI) and Spinopelvic Fixation (SPF)

Purpose: Aim of this retrospective cohort study was the comparison of the transiliac fixator (TIFI) and spinopelvic fixation (SPF) for fixation of dorsal pelvic ring fractures in terms of clinical outcome, complications, and quality of life. Methods: Thirty-eight patients (23 men, 15 women; mean age 47 ± 19 years) with dorsal pelvic ring fractures (type-C-injuries after AO/OTA) that have been stabilized by either TIFI (group TIFI, n = 22) or SPF (group SPF, n = 16) between May 2015 and December 2018 were retrospectively reviewed. Outcome measurements included demographic data, perioperative parameters, and complications and were obtained from the medical information system. Quality of life was assessed using the German version of the short form 36 (SF-36) and short muskuloskeletal function assessment (SMFA-D). Clinical results were assessed using Merle d'Aubigné-Score, Iowa Pelvic Score, and Majeed Pelvic Score. Results: Both groups show relatively good post-operative results, which has previously been reported. Quality of life was comparable in both groups. Group TIFI was slightly superior regarding complication rates, cutting/suture time, and fluoroscopy time. Group SPF seemed to be superior regarding pain and pelvic scores. Conclusion: None of the methods could demonstrate significant superiority over the other. Management of pelvic injuries remains a highly individual challenge adapted to the individual patients' condition. Nevertheless, if fractures allow for stabilization with TIFI, the use of this method should be taken into consideration as a less invasive and more tissue-conserving approach.

Medium-Term Patient-Reported Quality of Life and Activities of Daily Living in Surgically Treated Trauma Patients With Pelvic, Acetabular or Combined Pelvic and Acetabular Fractures in a Retrospective Single-Center Study

OBJECTIVE

To gain more insights in the medium-term patient-reported quality of life (QoL), activities of daily living (ADL), and number of complications in trauma patients with an acetabular fracture (AF), a pelvic fracture (PF), and those with a surgically combined pelvic and AF (PAF).

DESIGN

Retrospective single-center study.

SETTING

Level I academic trauma center.

PATIENTS/PARTICIPANTS

51 trauma patients with PF, AF, or PAF who were surgically treated between 2014 and 2017.

INTERVENTION

Open reduction and internal fixation.

MAIN OUTCOME MEASUREMENTS

Primary outcome measures are patient-reported outcome questionnaire, which includes 2 items, the QoL, as measured with the Short Form-12, and the ADL, as measured with the Lower Extremity Functional Scale. The secondary outcome parameter was the occurrence of complications during a follow-up of at least 2 years.

RESULTS

The mean physical component score (PCS) of the QoL (P = 0.03) and the ADL (P = 0.03) were significantly higher in patients with AF compared with patients with PF. The incidence of the overall postoperative complications did not significantly differ between the PF, AF, and PAF groups (P = 0.28).

CONCLUSIONS

This study found that the PCS of the QoL and the ADL in surgically treated trauma patients with PF were significantly lower compared with patients with AF. No significant differences were found in overall complication rate between the PF, AF, and PAF groups.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Radiostereometric Analysis Allows Assessment of the Stability and Inducible Displacement of Pelvic Ring Disruptions during Healing: A Case Series

There is currently no accurate data on fracture displacement during the rehabilitation of pelvic ring injuries. This study investigated the use of radiostereometric analysis (RSA) in assessing the stability of C1 pelvic ring injuries stabilised with a posterior plate and an anterior external fixator. Six patients, instructed to weight-bear as tolerated after surgery, were reviewed at 2, 4, 6, 12, 26, 52 and 104 weeks. The external fixators were removed at 6 weeks. Outcomes, including the Iowa Pelvic Score (IPS), and complications were recorded. Fracture stability was assessed using measurements on plain radiographs and RSA. All patients progressed to full weight-bearing without support within 6 weeks. At 104 weeks, the IPS was excellent in four patients, good in one patient and fair in one patient. Plain radiographs showed that all fractures were well reduced, and no loss of reduction occurred over time. By contrast, RSA measurements identified displacement in all cases. The maximum three-dimensional (3D) displacement at any time point in each patient ranged from 2 to 10 mm. Two patients with the largest displacement over time had the lowest IPS. RSA also demonstrated displacements above the currently defined normal threshold through the ‘un-injured’ sacroiliac joint in the same two patients, suggesting a subtle C2 injury, missed at initial assessment. This study demonstrates the limitations of plain radiographs in assessing pelvic fracture stability and displacement during healing, and the potential of RSA to monitor more accurately the effects of stabilisation and weight-bearing on fracture stability.

Comparability of Patient-reported Outcome Measures and Clinical Assessment Tools for Shoulder Function in Patients with Proximal Humeral Fracture

BACKGROUND

Patient-reported outcome measures (PROMs) are gaining increasing importance in the context of quality management. Different PROMs and scoring tools are available to assess shoulder function after proximal humeral fracture (PHFx). In Europe, these include the Constant-Murley Score (CS), Neer Score (NS), Oxford Shoulder Score (OSS), University of California at Los Angeles Score (UCLA) and Disabilities of the Arm, Shoulder and Hands Score (DASH). In addition, the health-related quality of life can be assessed by the PROMs Short Form 36 (SF-36) and EuroQol (EQ-5D). Although all these test instruments assess shoulder function, the components to be answered objectively and subjectively vary and thus the possibility of independent assessment. The aim of the present study is to compare the correlation between the results of the different PROMs and the clinical screening tools in patients with PHFx.

METHODS

76 patients who were treated with angular stable plate osteosynthesis for a proximal humeral fracture between 01/2001 and 12/2005 were included in this trial. The outcome was measured with PROMs or clinical scoring tools such as CS, NS, OSS, UCLA, DASH, SF-36 and EQ-5D and a correlation coefficient between those evaluation tools was calculated. In addition, a distinction was made between the two force measurement methods (wrist [HG] vs. deltoid muscle [DM]) for CS.

RESULTS

The correlation of the results of CS and NS (HG: r = 0.85; p < 0.001/DM: r = 0.93; p < 0.001), CS and UCLA (HG: r = 0.83; p < 0.001/DM: r = 0.86; p < 0.001), NS and UCLA (r = 0.91; p < 0.001) as well as DASH and OSS (r = 0.88; p < 0.001) was strongly expressed. A good comparability of the results was demonstrated between CS and OSS (HG: r = 0.63; p < 0.001/DM: r = 0.66; p < 0.001) and between CS and DASH (HG: r = 0.62; p < 0.001/DM: r = 0.61; p < 0.001). The correlation of CS (HG/DM) and UCLA with the EQ-5D index was also good. Assessment of the physical components of SF-36 with CS, NS, OSS, UCLA and DASH showed a moderate to good association, while the mental components of SF-36 showed a low correlation (p > 0.05).

CONCLUSION

The assessment of shoulder function after proximal humerus fracture showed a very strong correlation within the clinical questionnaires (CS/NS/UCLA) and the PROMs (OSS/DASH). A strong correlation also exists between the clinical questionnaires and the PROMs. There was only a moderate correlation with the EQ-5D. The moderate to strong correlation between the physical components of SF-36, with almost no correlation between the mental components of SF-36, indicates that the quality of life restriction is based on a physical, but not on a mental impairment.

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.

Tape suture for stabilization of incomplete posterior pelvic ring fractures-biomechanical analysis of a new minimally invasive treatment for incomplete lateral compression pelvic ring fractures

Background

Incomplete lateral compression fractures (including AO Type B2.1) are among the most common pelvic ring injuries. Although the treatment of choice remains controversial, sacroiliac (SI) screws are commonly used for the operative treatment of incomplete lateral compression fractures of the pelvic ring. However, the disadvantages of SI screws include the risk of nerve root or blood vessel injury. Recently, tape sutures have been found useful as stabilizing material for the treatment of injuries of the syndesmosis, the rotator cuff and knee ligaments. In this current study, we aimed to test the biomechanical feasibility of tape sutures to stabilize the pelvis in the setting of AO Type B2.1 injury.

Methods

Six human cadaveric pelvises underwent cyclic loading to compare the biomechanical stability of different osteosynthesis methods in a B2.1 fracture model. The methods tested in this experiment were a FiberTape® suture and the currently established SI screw. A 3D ultrasound tracking system was used to measure fracture fragment motion. Linear regression was used to model displacement and stiffness at the posterior and anterior pelvic ring.

Results

At the posterior fracture site, the FiberTape® demonstrated similar displacement (2.2 ± 0.8 mm) and stiffness (52.2 ± 18.0 N/mm) compared to the sacroiliac screw (displacement 2.1 ± 0.6 mm, P >  0.999; stiffness 50.8 ± 13.0 N/mm, P > 0.999).

Considering the anterior fracture site, the FiberTape® again demonstrated similar displacement (3.8 ± 1.3 mm) and stiffness (29.5 ± 9.0 N/mm) compared to the sacroiliac screw (displacement 2.9 ± 0.8 mm, P = 0.2196; stiffness 37.5 ± 11.5 N/mm, P = 0.0711).

Conclusion

The newly presented osteosynthesis, the FiberTape®, shows promising results for the stabilization of the posterior pelvic ring in AO Type B2.1 lateral compression fractures compared to a sacroiliac screw osteosynthesis based on its minimal-invasiveness and the statistically similar biomechanical properties.

Quality of life after pelvic ring fractures: Long-term outcomes. A multicentre study

AIMS

This study was conducted to determine long-term (5-10 years) health-related quality of life (HRQOL) and ceiling effects in patients with a pelvic ring fracture.

PATIENTS AND METHODS

We identified all patients with pelvic ring fractures after high-energy trauma admitted at two level 1 trauma centres in the Netherlands from 2006 to 2011. Patients were asked to complete the Majeed Pelvic Score (MPS), EuroQol-5D (EQ-5D) and Short Musculoskeletal Function Assessment (SMFA) questionnaires. HRQOL analysis used a multiple linear regression model.

RESULTS

In total, 136 patients returned the questionnaires. The median follow-up period was 8.7 years. The mean MPS and EQ-5D-VAS scores were 85.1 and 74, respectively. The mean EQ-5D index scores were 0.87, 0.81 and 0.82 in Tile B, A and C patients, respectively. The mean SMFA index was 24. A ceiling effect was observed for 1/3 of the patients. After multiple linear regression analysis, no differences were identified among the various fracture types for each questionnaire, with the exception of 2 subscales of the MPS.

CONCLUSION

Patients who suffer pelvic ring fractures generally have good HRQOL outcomes after 5-10 years. No significant differences were found among different fracture types. Long-term follow-up of patients with Tile C fractures is warranted.