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

Lower abdominal cyst complicated with suspected infection following INFIX internal fixation for pelvic fracture: a report of two rare cases

BACKGROUND

The Internal Fixator (INFIX) is a popular method, known for its minimal invasiveness and short operation time, for treating anterior pelvic ring fractures. Studies have shown that postoperative complications may occur, including anterolateral femoral cutaneous nerve injury, the femoral nerve paralysis, and delayed fracture healing. These complications are believed to be related to surgical stimulation, an excessively long lateral end of the connecting rod, a small distance between the screw and bone surface, insufficient pre-bending of the connecting rod, and difficulties in fracture reduction.

CASE PRESENTATION

We report two unique cases of lower abdominal pseudocyst complicated with suspected infection after INFIX treatment of pelvic fractures at our trauma center. Following surgical removal of the internal fixation, resolution of the cysts was observed in both patients, and subsequent postoperative follow-up revealed the absence of any residual sequelae. These cases have not been reported in previous literature reviews.

DISCUSSION

The lower abdominal cysts, potentially arising from the dead space created during intraoperative placement of the INFIX rod, may increase infection risk. The etiology remains uncertain, despite the presence of abnormal inflammation markers in both cases, and staphylococcus aureus found in one. These cysts were confined to the lower abdomen, not involving the internal fixation, and hence, only the INFIX was removed. Postoperative oral cefazolin treatment was successful, with resolved pseudocysts and no subsequent discomfort.

CONCLUSION

We report two unprecedented cases of post-INFIX abdominal cysts, with a suspected link to intraoperative dead space. Despite uncertain etiology, successful management involved INFIX removal and oral cefixime therapy. These findings necessitate further exploration into the causes and management of such complications.

Long-Term Follow-Up after Iliosacral Screw Fixation of Unstable Pelvic Ring Fractures

(1) Background: High-energy injuries of the pelvic ring are rare. The wide application of iliosacral screw fixation of the posterior pelvic ring is relatively new. The aim of the present study was to evaluate the long-term quality of life. (2) Methods: All patients treated with an iliosacral screw for a posterior pelvic ring stabilization after high-energy trauma at a level 1 trauma center between 2005 and 2015 were included. Pelvic ring injuries were classified according to the Tile classification adapted by AO/ASIF. The clinical evaluation included the patient-oriented questionnaires surveys of the Majeed Score, Iowa Pelvic Score (IPS), Work Ability Index (WAI), SF-36, EQ5D-5L. (3) Results: A total of 84 patients were included with a median follow-up of 130.1 months (IQR 95.0-162.0 months). The median ISS was 22.5 (IQR 16.0-29.0), mean Majeed Score 83.32 (SD ± 19.26), IPS 77.88 (SD ± 13.96), WAI 32.71 (SD ± 11.31), SF-36 PF 71.25 (SD ± 29.61) and EQ5D-5L 0.83 (SD ± 0.21). There was a notably difference between uni- and bilateral pelvic fractures (p = 0.033) as well as a correlation with the ISS (p = 0.043) with inferior functional outcome measured by IPS. (4) Conclusions: Long-term follow-up of iliosacral screw fixation of unstable pelvic ring fractures showed a good quality of life and functional outcome with equal EQ5D-5L results and inferior SF-36 physical functioning compared to the German population.

Does the residual displacement of pelvic ring affect the functional outcome in pelvic ring injures?

PURPOSE

The effects of residual displacement on the functional outcome of the patient are not distinctly known and the acceptability criteria of residual displacement of the pelvic ring remain disputed. The purpose of this study is to evaluate the effect of residual displacement on functional outcome in pelvic ring injuries.

MATERIALS AND METHODS

A total of 49 patients with pelvic ring injuries (both operative and non-operative) were followed up for six months. Anteroposterior (AP), Vertical and rotational displacements were measured at admission, after surgery and at six months. Resultant displacement (vector addition of AP and vertical displacement) was taken for comparison. Displacement was graded as excellent, good, fair and poor according to Matta's criteria. Functional outcome assessment was done at six months using Majeed score. Work adjusted Majeed score was calculated for non-working patients by taking the percentage score.

RESULTS

We compared the means of residual displacement with functional outcome (Excellent/Good/Fair) and found that there was no significant difference between the groups in operative (P=0.33) or non-operative patients (P=0.09). This showed that patients with relatively higher residual displacement also had satisfactory functional outcomes. The functional outcomes were compared after dividing the residual displacement into 2 groups: <10 mm and >10 mm and no significant difference was found in outcomes for either operative or non-operative patients.

CONCLUSION

Up to 10 mm of residual displacement is acceptable in pelvic ring injuries. More prospective studies with a longer follow up are needed for determination of correlation between reduction and functional outcome.

A retrospective analysis of minimally invasive internal fixation versus nonoperative conservative management of pelvic ring fragility fractures and the elderly

OBJECTIVE

We aimed to investigate the adoption of treatment patterns for hip fractures combined with minimally invasive surgical treatment of fragility fractures of the pelvis in older individuals and reviewed and analysed the treatment efficacy and feasibility.

METHODS AND DATA

From September 2017 to February 2021, 135 older individuals with fragility fractures of the pelvis were admitted to our hospital. We retrospectively analysed patients who received surgical or conservative treatments. The general preoperative data, including sex, age, disease duration, cause of injury, AO/OTA type, BMI, bone mineral density, time from injury to admission, time from injury to surgery, ASA classification, number of underlying diseases, mean bed rest, clinical fracture healing, VAS score and Majeed functional score, were recorded.

RESULTS

The mean follow-up time for all 135 patients was 10.5 ± 3.6 months. Among 135 patients, 95 survived, and 11 and 29 patients passed after the surgical (mortality rate = 17.74%) and conservative (mortality rate = 39.73%) treatments, respectively. The average follow-up time for the 95 surviving patients was 14.5 ± 1.8 months. The Majeed and VAS scores for the operation group were significantly better than those of the conservative group. The bed rest and fracture healing times were also shorter in the surgical treatment group than in the conservative group.

CONCLUSION

The use of a minimally invasive surgical treatment combined with the geriatric hip fracture treatment model to treat fragility fractures of the pelvis improved the quality of life in older patients.

Modified percutaneous iliosacral screw and anterior internal fixator technique for treating unstable pelvic fractures: a retrospective study

BACKGROUND

The commonly used technique for treating unstable pelvic fractures with sacroiliac screws and anterior internal fixator (INFIX) is prone to complications, such as injury to the pelvic vasculature and nerves, life-threatening bleeding, lateral femoral cutaneous neuritis, and wound infection. This study investigated the clinical effects of using a modified percutaneous iliosacral screw and INFIX technique for treating unstable pelvic fractures.

METHODS

A retrospective analysis of minimally invasive internal fixation using modified incision of an anterior-ring INFIX application combined with modified percutaneous iliosacral screw placement was performed for 22 cases of unstable pelvic fractures from January 2017 to December 2018. Based on the Tile classification, there were 4 type B1, 7 type B2, 5 type B3 and 6 type C1 injuries. Preoperatively, the length and orientation of the internal fixation were computer-simulated and measured. On postoperative day 3, pelvic radiographs and three-dimensional computed tomograms were used to assess fracture reduction and fixation. All patients were regularly followed up at 4 weeks, 12 weeks, 6 months, 12 months, 24 months and annually thereafter. Fracture healing, complications, visual analogue scale (VAS) scores, the quality of fracture repositioning and Majeed score were assessed during follow-up.

RESULTS

All patients were followed up for a mean of 25.23 ± 1.48 months. All fractures healed without loss of reduction and no patient showed evidence of delayed union or nonunion. Two years postoperatively, the mean VAS score was 0.32 ± 0.09 and the mean Majeed score was 94.32 ± 1.86.

CONCLUSION

The modified percutaneous iliosacral screw technique increases the anterior tilt of the sacroiliac screw by shifting the entry point posteriorly to increase the safety of the screw placement. Downward modification of the INFIX incision reduces the risk of lateral femoral cutaneous nerve injury. This technique is safe, effective and well tolerated by patients.

A clinical and biomechanical comparison of INFIX plus single versus double sacroiliac screw fixation for unstable pelvic ring injury

BACKGROUND

The aim of this study is to compare the clinical and biomechanical outcome of INFIX plus single with two sacroiliac screw fixation for unstable pelvic fractures of Type C.

METHODS

Sixteen cadavers were randomly subjected to INFIX plus single or double sacroiliac screw fixations and then mounted onto the ElectroForce loading machine under different vertical loads. To investigate the clinical outcomes of the two techniques, nineteen patients were retrospectively analyzed. The main outcome measures were postoperative radiographic reduction grading (using the Tornetta and Matta grading system), functional outcome (using the Majeed scoring system), and incidence of complications.

RESULTS

In the biomechanical study, INFIX plus double sacroiliac screw fixation showed better biomechanical stability than fixation with a single sacroiliac screw (p < 0.05). In our clinical case series, all 19 patients had bony union 6 months after the operation. INFIX plus double sacroiliac screw fixation also demonstrated a better functional outcome and a higher radiographic satisfactory rate than INFIX plus single sacroiliac screw fixation (79.25 ± 5.47; 91.33 ± 4.97; p < 0.05), (77.78% vs. 60%; p = 0.05). One patient in INFIX plus single-screw fixation group had screw loosening at 6-month follow-up postoperatively. One case in each group suffered heterotopic ossification and the lateral femoral cutaneous nerve paralysis, and one patient suffered from infection.

CONCLUSION

INFIX plus double sacroiliac screw fixation demonstrated more stability in cadaveric biomechanical analysis and better clinical outcomes than INFIX plus single sacroiliac screw fixation.

Outcomes and complications of the INFIX technique for unstable pelvic ring injuries with high-velocity trauma: a systematic review and meta-analysis

BACKGROUND

The pelvic INFIX technique has been proposed as a useful alternative to symphyseal plating for management of unstable pelvic ring injuries. The minimally invasive nature of the procedure, shorter operative time and less perioperative blood loss have been purported as potential advantages.

QUESTIONS/PURPOSES

This systematic review and meta-analysis were conducted to determine the outcomes and complications of the INFIX technique for unstable pelvic ring injuries.

METHODS

A systematic review of literature was performed on the PubMed, EMBASE and Scopus databases. Prospective and retrospective studies in all languages, whether comparative or non-comparative, pertaining to the use of INFIX in pelvic fractures were included. Studies which did not evaluate INFIX, case reports, conference abstracts and those with less than 10 cases were excluded. Cadaveric studies, technique papers and studies that did not describe the prespecified outcome measures were also excluded. Meta-analysis consisted of two different arms: a comparative arm, to compare INFIX to symphyseal plating, and a non-comparative meta-analysis arm, to determine pooled rates of outcomes and complications. Risk of bias was determined by the Methodological Index for Non-Randomised Studies (MINORS) tool.

RESULTS

A total of 22 studies were included in the systematic review, of which 7 were comparative and 15 were non-comparative. 746 patients were included for qualitative analysis and pooled analysis done for 589 patients. The average follow-up of these studies ranged from a minimum of 5.4 months to a maximum of 54 months. Comparative meta-analysis (n = 3 studies) of plating and INFIX showed significantly lesser blood loss (mean difference = 176.46 mL; 95% CI - 207.54 to - 145.38) and shorter operative time (mean difference = 26.43 min, 95% CI - 31.79 to - 21.07) with INFIX, but no significant difference in the overall complication rates (OR 1.59, 95% CI 0.83-3.05) and functional outcome scores (mean difference = - 2.51, 95% CI - 5.73 to 0.71). Pooled analysis showed overall good radiological (mean percentage of excellent to good reduction = 91.4%, 95% CI 0.860-0.969) and functional outcomes (mean Majeed score = 86.48, 95% CI 83.34-89.61) with INFIX. The most common complications were lateral femoral cutaneous nerve (LFCN) injury (overall rate 28%, 95% CI 15.1-41%) and heterotopic ossification (HO) (overall rate 9.4%, 95% CI 5.5-13.3%); rates of other complications were low. Significant heterogeneity was noted in the pooled analysis of blood loss, operative time, functional outcome, HO and LFCN injury. The overall strength of evidence was found to be weak.

CONCLUSION

The INFIX technique can be considered as a viable alternative to symphyseal plating for unstable pelvic ring injuries. It has the advantages of shorter operative times and less blood loss, along with comparable functional outcomes, when compared to plating. Overall, good functional outcomes can be expected. However, well-designed, multi-center randomized controlled trials are needed to conclusively prove the benefit of this technique.

Management of LC Type I (LC-1) Pelvic Injuries with Complete Sacral Fracture: Comparison of Solitary Anterior Fixation with Combined Anterior-Posterior Fixation

BACKGROUND

Management of LC-1 type pelvic injuries, particularly in patients with complete sacral fracture (LC-1 PICSF, OTA type 61-B2.1), remains controversial. Specific indications for solitary fixation remain unclear, and there is a paucity of outcomes data in comparison to combined fixation. We undertook a retrospective study in patients with LC-1 PICSFs to compare outcomes between solitary anterior fixation and combined anterior-posterior fixation.

METHODS

A retrospective cohort study was conducted with enrollment from 2016 to 2018 at a single tertiary-referral center in China. Adults with operatively managed LC-1 PICSFs were enrolled. Patients with sacral displacement < 1 cm as assessed by axial CT received solitary anterior ring fixation (group A); patients with displacement ≥ 1 cm received combined fixation of both the anterior and posterior rings (group B). Reduction was confirmed by manipulation under anesthesia. Patients followed up for at least 24 months postoperatively. Primary outcome was function (Majeed score). Secondary outcomes included intraoperative characteristics, pain (VAS score), quality of fracture reduction (Tornetta and Matta radiographic grading), rate of nonunion, early weight-bearing status, and complication rate.

RESULTS

68 (89%) of 76 enrolled patients completed follow-up. Patients in group A exhibited improved operative times, less time under fluoroscopy, and less blood loss as compared to group B. There were no significant differences between groups A and B regarding quality of fracture reduction, rate of union, functional outcomes, or rate of complications. Notably, group B patients were more likely to achieve full early weight-bearing.

CONCLUSION

LC-1 PFCSFs can get benefits from ORIF; the treatment algorithm should be differently made following the degree of the sacral fractures displacement. Less than 1 cm sacral fracture displacement may get good functional outcomes from solitary anterior fixation. However, for the sacral fractures displacement greater or equal to 1 cm, both the anterior and posterior pelvic rings should be surgical stabilization.

Minimally invasive 360-degree pelvic ring fixation using a combination of crab-shaped fixation and pelvic internal fixator for unstable pelvic ring fracture: A case report

Surgery with both anterior and posterior fixation is recommended for unstable pelvic ring fractures; nonetheless, the surgical method remains controversial. Crab-shaped fixation is a minimally invasive and strong posterior fixation method using spinal instruments that can reduce vertical dislocations. The use of pelvic internal fixator as a minimally invasive anterior fixation method has been reported. It is recommended in cases where there is an open wound in the lower abdomen or damage to the pelvic organs. Conversely, to the best of our knowledge, there has been no report on the combined use of crab-shaped fixation and pelvic internal fixator to date. We performed a minimally invasive 360-degree fixation using a combination of crab-shaped fixation and pelvic internal fixator for an unstable pelvic ring fracture (AO-C2) and sacral fracture (Denis zone II) with 15-mm vertical dislocation. The sacral fracture was accompanied by a large bone fragment in the spinal canal, which was suspected to have caused neuropathy. Therefore, in addition to posterior fixation, we performed decompression and removed the bone fragment. Postoperative computed tomography revealed that the sacral vertical dislocation was reduced to 7.5 mm. The patient started getting out of bed on postoperative day 2. His neuropathy improved after surgery. Owing to abdominal discomfort, pelvic internal fixator was extracted at 3 months postoperatively. Bone fusion was completed, and posterior fixation was removed at 9 months postoperatively. Two years after, the patient walks independently and has returned to work. Minimally invasive 360-degree pelvic ring fixation is a treatment option for an unstable pelvic ring fracture (AO-C2).

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CSF360 is a modified CSF surgical technique.

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Free bone fragment and 360° pelvic ring fixation CSF and INFIX were performed.

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Unstable pelvic ring fractures can be fixed to 360° of circumference.

Infection after the use of INFIX in Pelvic Ring Injuries

INTRODUCTION

The purpose of this study is to report on infection with anterior subcutaneous internal pelvic fixation (INFIX) for pelvic ring injuries and the outcomes of treatment.

METHODS

An IRB-approved retrospective study was performed using trauma databases of a level one and level two trauma center from 2012-2018. Infection after the INFIX procedure was diagnosed in 10 of 179 cases. Treatment included formal irrigation and debridement, removal of the hardware, and culture-specific antibiotics. Patients were followed for a minimum of 12 months. Recorded outcomes include X-rays, Majeed scores, and the presence of any loss of reduction using reduction parameters.

RESULTS

Time to detect the infection was 54.2 ± 24.3 days (range 24-90, median 56 days). Staphylococcus aureus was the most common bacteria isolated. The average follow-up was 830 ± 170 days (range 575-1088 days). All patients went on to the radiographic union. There were no recurrent infections or osteomyelitis at the latest follow-up. Patients maintained their reduction after INFIX removal (KI), and Majeed scores ranged from 72 to 96 (seven good, three excellent).

DISCUSSION

Infections after using the INFIX procedure were dealt with by irrigating and debriding the wounds, removing the INFIX with culture-specific antibiotics for 2-6 weeks. Implants were maintained for at least 25 days, and there was no loss of reduction. There were no long-term sequelae noted in this small series or the literature review included in this paper.

Functional outcomes of the anterior subcutaneous internal pelvic fixator (INFIX) technique for pelvic ring injuries: A case series

INTRODUCTION

Anterior external fixation is a well-established technique for treating pelvic ring injuries, but many complications are associated with it. The subcutaneous anterior internal fixator (INFIX) technique is associated with reduced complication rates and is less uncomfortable for patients.

OBJECTIVE

This study evaluated functional outcomes among patients with pelvic ring injuries treated using the INFIX method.

PATIENTS AND METHODS

In this retrospective case series, patients treated using the INFIX technique were reviewed for functional outcomes, using the Iowa Pelvic Score (IPS). Thirty-four patients, of mean age 39.2 years, were evaluated after a mean follow-up of 1.2 years.

RESULTS

Twenty-three of the 34 patients experienced reduction classified as excellent, and eleven as good, with no instances of moderate or poor reduction. One patient developed implant exposure and infection during follow-up. Twenty-six ultimately experienced an excellent or good functional result. The average final IPS was 79.4 (range: 48-100).

CONCLUSION

Our results reinforce prior evidence that the INFIX method is safe for fixating pelvic ring lesions. Most of our patients also experienced excellent or good functional recovery, suggesting that this technique is a viable option for treating certain pelvic ring injuries.

Minimally invasive internal fixation for unstable pelvic ring fractures: a retrospective study of 27 cases

Background

This study aimed to evaluate the radiographic and clinical outcomes of anterior subcutaneous internal fixation (INFIX) with or without posterior fixation for the treatment of unstable pelvic fractures.

Methods

Intraoperative blood loss, operation time, and duration of hospital stay were recorded, and fracture union and postoperative complications were evaluated. The fracture reduction quality was evaluated using the Matta score, pelvic deformity index (PDI), and pubic symphyseal width (PSW). In addition, the functional recovery and general quality of life were evaluated using the Majeed score and the 12-Item Short-Form Survey (SF-12), respectively. Furthermore, sacral nerve injury was evaluated using the Gibbons classification.

Results

Twenty-seven patients (14 males and 13 females) with an average age of 37.4 years were followed up for a mean of 22 months. The average operation time, median intraoperative blood loss, and average duration of hospital stay were 129 ± 47 min, 100 mL, and 22 ± 13 days, respectively. All patients achieved bony union with an average union time of 13.3 weeks. Furthermore, the average PDI and PSW were 0.07 ± 0.04 vs. 0.04 ± 0.03 (P = 0.009) and 1.15 ± 1.36 vs. 0.54 ± 0.17 (P = 0.048) before and after the operation, respectively. In 78% of the patients, the Matta or Majeed scores were excellent or good. The SF-12 physical and mental health scores were 45.1 ± 10.2 and 53.2 ± 6.3, respectively. Furthermore, one superficial surgical site infection, one loosening of INFIX, one lateral femoral cutaneous nerve irritation, one femoral nerve injury, and two implant discomforts due to the bar were noted. Among five patients with sacral nerve injuries, four were asymptomatic, and one just had paresthesia at the last follow-up.

Conclusion

INFIX with or without sacroiliac screws can achieve satisfactory radiographic and functional outcomes in the treatment of unstable pelvic ring fractures.

Trial registration

ChiCTR2000038812. Registered 04 October 2020. Retrospectively registered.

INFIX-safe and effective surgical option for complex fracture patterns of the anterior pelvic ring: A prospective single center study

Background

Complex fracture patterns of anterior pelvic ring are a challenge and usually needs extensive surgeries. The purpose of this study was to evaluate INFIX as a minimally invasive procedure for such injuries in terms of feasibility, outcomes and complications in the Indian population.

Methods

Patients with complex fracture patterns of anterior pelvic ring were selected for anterior INFIX application along with standard posterior stabilization. Outcomes were assessed radiographically by Matta's criteria and amount of displacement. Post-operative CT scan for relation of implant to vital structures and Doppler at varying hip flexion for possible vascular occlusion was used. Functional outcomes included both disease specific scores (Majeed score, IOWA pelvic score) and quality of life scores (SMFA, SF-12). Complications were also noted.

Results

12 cases out of 112 patients had complex fracture pattern of the anterior ring. Most common injury pattern were LC-3 and VS (n = 6 and 3) Young and Burgess type. The average follow up was 6 months. Fracture reduction as per Matta's criteria was excellent in 10 (83.3%) cases and good in 2 (16.6%) cases with functional outcomes excellent in 11 cases, and a mean Majeed score of 92.67 ± 5.8. The average SMFA score was 51 ± 4.39 and mean SF-12 scores for physical and mental health were 48.493 ± 6.74 and 56.370 ± 4.04 respectively. Complications noted were lateral femoral cutaneous nerve palsy (1/24 nerves), skin dehiscence (n = 2), infection (n = 2) and sacral nonunion (n = 1).

Conclusion

INFIX is a safe and effective minimally invasive technique for addressing complexfracture patterns involving the anterior half of pelvic ring with excellent fracture reduction, radiological and functional outcomes and predictable fracture healing.

Inaccuracies in the Use of the Majeed Pelvic Outcome Score: A Systematic Literature Review

OBJECTIVES

To evaluate the accuracy with which the Majeed Pelvic Score has been reported in the English literature.

DATA SOURCES

Databases used to search for literature were PubMed, Embase, and Ovid, restricted to English language from inception to October 2, 2018.

STUDY SELECTION

Search words used were: Majeed, pelvis, and outcome.

DATA EXTRACTION

Articles were assessed for descriptions of scoring and proper reporting of Majeed Pelvic Outcome Score.

DATA SYNTHESIS

Descriptive statistics were used to report the outcome of our findings.

CONCLUSIONS

Ninty-two English articles were identified. Twenty-four (26%) articles were identified as including methodology related to the use and scoring of the Majeed Pelvic score. The remaining 68 presented mean Majeed scores with no methodological information. None (0/92) discussed how the range of possible scores for the most severe function was applied. Six (7%) reported adjusted scores for patients not working. Three (3%) included a discussion of the scores as adjusted for patients working before injury compared with those not working. Ten (11%) addressed the categorization of scores by excellent to poor describing what raw scores defined those categories. We observed poor accuracy and notable inconsistency in the use and reporting of the Majeed Pelvic Outcome Score in the literature. These data demonstrate that interpretation and comparison of research reporting this score should be done cautiously. Future studies should include specific information as to how the Majeed instrument calculated to allow for verification of the presented scores and subsequent conclusions.

[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.

Use of INFIX for managing unstable anterior pelvic ring injuries: A systematic review

INTRODUCTION

Subcutaneous screw rod system which is popularly known as Pelvic internal fixator (INFIX) has emerged as an alternative to external fixators in management of unstable pelvic injuries. INFIX has shown various advantages over external fixation such as reduced infection rate and patient morbidity. However, it has its own set of complications such as lateral femoral cutaneous nerve injury, heterotopic ossification, femoral nerve palsy etc. We intended to conduct a systematic review of the current literature to assess outcomes and complications with INFIX technique of fixation.

METHODS

A comprehensive search of literature was performed based on Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines and online database of EMBASE, PubMed, Medline and Scopus was searched for all studies in English language till March 2020. Included studies were reviewed for demographic data, fracture type/classification, radiological outcome and functional outcomes. The inclusion criteria were: 1. Studies in English language 2. Clinical studies reporting use of INFIX technique in pelvis fracture where clinical and radiological outcomes were reported.

RESULTS

Twenty-two studies fulfilling inclusion and exclusion criteria were included in this systematic review with total of 619 patients. Radiographic parameters and outcome measures were infrequently reported. Fixation with INFIX in these fractures leads to 87% excellent to good radiological results and 84% excellent to good functional results. Complications include lateral femoral cutaneous nerve irritation (25.3%), heterotopic ossification (24.7%), infection (3%), and femoral nerve palsy (1.6%); which is likely related to placing the bar and screws too deep.

CONCLUSION

This analysis supports the use of INFIX in management of unstable pelvis fractures where anterior fixation is required.

[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.

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.

Modified less invasive anterior subcutaneous fixator for unstable Tile-C-pelvic ring fractures: a biomechanical study

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.

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.