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

doi:10.1016/j.jor.2021.01.004

Journal of Orthopaedics

Volume 23, January–February 2021, Pages 142-149

https://doi.org/10.1016/j.jor.2021.01.004 Get rights and content

Abstract

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.

Introduction

Pelvic fractures are high energy injuries with disruption of the anterior and posterior bony and/or ligamentous structures. Fracture pattern dictates the type of implants and fixation strategy. Posterior injury is usually addressed with iliosacral screws, recon plates, or a combination based on fracture morphology whereas anteriorly a simple injury pattern like a diastasis (in APC injuries) can be fixed with symphyseal plating through pffenensteil incision. The challenge to reduction and fixation is of complex fracture patterns of the anterior ring (bilateral superior pubic rami and inferior pubic rami fractures, comminuted fractures, segmental fractures which remain unstable after posterior fixation). Such cases need extensile anterior approach like a modified Stoppa's or bilateral ilioinguinal approach to address the injury. These extensile approaches are obviously associated with increased operative time, blood loss and increased risk of infection.

Definitive external fixation for anterior ring injuries, which is usually reserved for cases with urogenital injuries and open injuries with inadequate soft tissue coverage can also be used for such complex fracture patterns of anterior ring.¹^,²^,³ However, it is associated with various complications like pin site infection rates (2%–40%), limited access to the abdomen, decreased patient mobility, along with aseptic loosening and are not accepted well by patients.³

Procedures comprising of pedicle screws fixed into the ilium on either side and connected to each other with subcutaneous rod, with or without fixation into the symphyseal region are described as the pelvic bridge or INFIX technique. This procedure is an MIO technique (Minimally invasive osteosynthesis) and has potential benefits like fewer soft tissue infections, better pain control, better patient mobilization and hence faster rehabilitation. This procedure could be of potential use in complex fracture patterns of anterior pelvic ring and avoid morbidity due to decreased intraoperative time and blood loss compared to conventional techniques.⁴

As the procedure is an MIO technique relying upon indirect reduction technique and therefore functional reduction, its utility in achieving reduction, maintaining reduction, and achieving bony union needs to be evaluated.

The present study was conducted to evaluate the subcutaneous pedicle screw–bar fixation (INFIX) as a minimally invasive procedure for unstable pelvic ring injuries with complex fracture patterns of the anterior ring, in the respects of its feasibility, merits, limitations, safety, and complications in the Indian population.

Section snippets

Materials and methods

Study Design and Setting- This study was a prospective analysis of patients presenting with pelvic fractures to a tertiary care center (single center) between Jan 1, 2018 to Dec 31, 2018.

Participants- All cases were screened by 2 pelvic surgeons independently and assessed for need of anterior INFIX. In case of conflicting decision, a close discussion between both surgeons was done and a consensus was arrived upon. The basis for selection of patients was primarily the fracture morphology with

Results

A total of 112 patients presented with pelvic fractures during the study duration, of which 12 patients were selected for INFIX application (Baseline data illustrated in Table 1). The mean age of the patients was 37.08 ± 15.65 years with an average follow up of 6 months. According to Young and Burgess classification, 1 patient was classified as LC2 type, 6 patients as LC3 injury pattern type, 3 patients as VS type and 2 patients fell into combined mechanism type. Tile's anterior pelvic

Discussion

Pelvic injuries are complex injuries with disruption of multiple bony and/or ligamentous components both anteriorly and posteriorly. Initially most anterior injuries were left unattended after posterior stabilization. Over time the importance of addressing anterior injury has been evolving and emphasized.⁷^,⁸ Commonly used methods for anterior fixation include plating, percutaneous screws and external fixator. Anterior plating is considered as method of fixation for symphyseal injuries.⁴

Conclusion

INFIX and percutaneous iliosacral screws combined together is a biomechanically stable and effective minimally invasive surgical technique for definitive management of complex pelvic ring injuries in presence of anterior comminution. It is capable of achieving good fracture reduction with good functional and radiological outcomes leading to better patient satisfaction. The vital structures which are in close proximity to implant are not at risk if safe surgical technique is followed as shown by

Source of funding

Nil.

Declaration of competing interest

None.

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Cited by (5)

Functional outcomes of the anterior subcutaneous internal pelvic fixator (INFIX) technique for pelvic ring injuries: A case series
2021, Injury
Citation Excerpt :
In a multicenter study, Vaidya et al. [3] evaluated the function of patients undergoing INFIX and reported that 100% of their patients could sit, stand, and walk with the device in place. Sharma et al. [23] reported an overall Majeed score of 92.6 points and an average IPS of 93.9 points. Steer et al. [1] reported an average IPS of 79.7, ranging from 52 to 100.
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.
This study evaluated functional outcomes among patients with pelvic ring injuries treated using the INFIX method.
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.
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).
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.
Lower abdominal cyst complicated with infection following INFIX internal fixation for pelvic fracture: A report of 2 rare cases
2023, Research Square
Progress in minimally invasive techniques for pelvic fractures
2023, Chinese Journal of Orthopaedic Trauma
Surgical site infections after stabilization of pelvic ring injuries: a retrospective analysis of risk factors and a meta-analysis of similar studies
2023, International Orthopaedics
Arterial angioembolisation versus pre-peritoneal pelvic packing in haemodynamically unstable patients with complex pelvic fractures: a meta-analysis
2023, European Journal of Trauma and Emergency Surgery

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

Abstract

Background

Methods

Results

Conclusion

Introduction

Section snippets

Materials and methods

Results

Discussion

Conclusion

Source of funding

Declaration of competing interest

Injury

J Clin Orth Trauma

Injury

Injury

Distraction external fixation in lateral compression pelvic fractures

J Orthop Trauma

Internal fixation in pelvic fractures and primary repairs of associated genitourinary disruptions: a team approach

J Trauma Acute Care surg

INFIX versus plating for pelvic fractures with disruption of the symphysis pubis

Int Orthop

Fractures of the pelvis

Outcome of operatively treated unstable posterior pelvic ring disruptions

Clin Orthop Relat Res

OTA highlight paper predicting future displacement of nonoperatively managed lateral compression sacral fractures: can it be done?

J Orthop Trauma

Minimally invasive treatment of unstable pelvic ring injuries with modified pedicle screw–rodfixator

J Int Med Res