Spinopelvic Fixation in Complex Sacral Fractures

The Surgical Algorithm for the AO Spine Sacral Injury Classification System

STUDY DESIGN

Global cross-sectional survey.

OBJECTIVE

To establish a surgical algorithm for sacral fractures based on the Arbeitsgemeinschaft für Osteosynthesefragen (AO) Spine Sacral Injury Classification System.

SUMMARY OF BACKGROUND DATA

Although the AO Spine Sacral Injury Classification has been validated across an international audience of surgeons, a consensus on a surgical algorithm for sacral fractures using the Sacral AO Spine Injury Score (Sacral AOSIS) has yet to be developed.

METHODS

A survey was sent to general orthopedic surgeons, orthopedic spine surgeons, and neurosurgeons across the five AO spine regions of the world. Descriptions of controversial sacral injuries based on different fracture subtypes were given, and surgeons were asked whether the patient should undergo operative or nonoperative management. The results of the survey were used to create a surgical algorithm based on each subtype's sacral AOSIS.

RESULTS

An international agreement of 70% was decided on by the AO Spine Knowledge Forum Trauma experts to indicate a recommendation of initial operative intervention. Using this, sacral fracture subtypes of AOSIS 5 or greater were considered operative, while those with AOSIS 4 or less were generally nonoperative. For subtypes with an AOSIS of 3 or 4, if the sacral fracture was associated with an anterior pelvic ring injury (M3 case-specific modifier), intervention should be left to the surgeons' discretion.

CONCLUSION

The AO Spine Sacral Injury Classification System offers a validated hierarchical system to approach sacral injuries. Through multispecialty and global surgeon input, a surgical algorithm was developed to determine appropriate operative indications for sacral trauma. Further validation is required, but this algorithm provides surgeons across the world with the basis for discussion and the development of standards of care and treatment.

Minimally invasive bilateral fixed angle locking fixation of the dorsal pelvic ring: clinical proof of concept and preliminary treatment results

PURPOSE

Dorsal pelvic ring fractures may result from high energy trauma in younger patients or from osteoporosis as fragility fractures in elderly patients. To date, no strong consensus exists on the best surgical technique to treat posterior pelvic ring injuries. The aim of this study was to evaluate the surgical performance of a new implant for angle-stable fixation of the posterior pelvic ring and patient outcome.

METHODS

In a prospective pilot study, 27 patients (age: 39-87 years) with posterior pelvic ring fractures classified according to the AO classification (n = 5) or to the fragility fractures of the pelvis (FFP) classification (n = 22) were treated using the new implant. During a follow-up period of 1 year, surgical parameters of the implantation technique, complication rate, morbidity, mortality, preservation of patient mobility, and social independence were evaluated.

RESULTS

No implant misplacement or failure was observed. Two patients developed symptomatic spinal canal stenosis at L4/L5 following mobilization. MRI diagnosis proved the implant was not responsible for the symptoms. In one case, an additional plate stabilization of a pubic ramus fracture was necessary 6 months later. There was no inpatient mortality. One patient died due to her underlying oncological disease within the first 3 months. The main outcome parameters were pain, mobility, preservation of independent living and employment.

CONCLUSION

Operative instrumentation of dorsal pelvic ring fractures should be stable enough to allow for immediate weight bearing. The new locking nail implant offers percutaneous reduction and fixation options and may decrease the generally observed rate of complications.

TRAIL REGISTRATION

German Clinical Trials Register ID: DRKS00023797, date of registration: 07.12.2020.

Current Minimally Invasive Surgical Concepts for Sacral Insufficiency Fractures

An increasing incidence of sacral insufficiency fractures in geriatric patients has been documented, representing a major challenge to our healthcare system. Determining the accurate diagnosis requires the use of sectional imaging, including computed tomography and magnetic resonance imaging. Initially, non-surgical treatment is indicated for the majority of patients. If non-surgical treatment fails, several minimally invasive therapeutic strategies can be used, which have shown promising results in small case series. These approaches are sacroplasty, percutaneous iliosacral screw fixation (S1 with or without S2), trans-sacral screw fixation or implantation of a trans-sacral bar, transiliac internal fixator stabilisation, and spinopelvic stabilisation. These surgical strategies and their indications are reported in detail. Generally, treatment-related decision making depends on the clinical presentation, fracture morphology, and attending surgeon's experience.

Role of triangular osteosynthesis in vertically unstable transforaminal sacrum fractures: clinical and radiological outcomes

PURPOSE

We aim to report clinical and radiological results of triangular osteosynthesis for a homogenous group of vertically unstable transforaminal sacral fractures.

METHODS

Between 2013 and 2018, 22 consecutive patients with unstable sacral fractures were treated with triangular osteosynthesis consisting of iliosacral screw augmented by spinopelvic fixation. Patients were followed up prospectively as a single cohort. Bone union, complications, clinical and radiological outcomes were investigated.

RESULTS

Mean follow-up was 3.1 years (12-76 months). There was one bilateral fracture. Two patients underwent anterior plating for pubic symphyseal disruption. Based on Majeed and Iowa pelvic scores, 13 patients had excellent, seven had good and two had fair clinical outcome. All the patients could perform squatting, sitting cross-legged and kneeling without any restrictions. There were no additional neurological injuries. One patient had non-union of sacral fracture, one patient had deep infection, one patient had marginal wound necrosis and two patients complained of pain related to implant prominence. Two patients had connecting rod backout. All but one patient attained pre-operative work status.

CONCLUSION

Triangular osteosynthesis is a reliable procedure in treating unstable transforaminal sacral fractures. It permits early weight-bearing and facilitates faster functional recovery. Careful attention to details such as sacral dysmorphism, soft tissue injury, implant placement and anterior pelvic injury helps in keeping complications to an acceptable rate.

Traumatic spinopelvic dissociation managed with bilateral triangular osteosynthesis: Functional and radiological outcomes, health related quality of life and complication rates

BACKGROUND

Spinopelvic dissociation (SPD) is difficult to manage and is associated with high mortality and morbidity, including concomitant orthopaedic polytrauma, spine injuries, pelvic ring disruptions, neurological, soft-tissue, and vascular injuries. The purpose of this study is to evaluate the functional and radiological outcomes; health related quality of life and complication rates of patients with traumatic spinopelvic dissociation underwent bilateral triangular osteosynthesis (TOS).

METHODS

The study was approved by the medical school's institutional review board (IRB). Prospective data collection of nineteen consecutive cases of traumatic SPD were included in the study from October 2015 to August 2018. Bilateral TOS was performed to manage all patients with SPD. The clinical outcome for fractures was analyzed with Majeed function assessment. Health Related Quality of Life (HRQoL) was assessed with the EQ-6D questionnaire. The reduction quality was evaluated according to Matta criterion. CT scanning was used to verify the fracture union in patients at 24^th weeks postoperatively.

RESULTS

There were 12 women and 7 men with an average age of 47.2±8.4 years (range, 17-62 years). The average follow-up time was 25.2±3.7 months (average, 22-45 months). The most common mechanism of injury was falling (57%). According to Majeed functional scoring, the results were excellent in 12 cases, good in 5 cases and fair in 2 cases. The median EQVAS score was 78.9±8.4. 15 patients (78.9%) turned back to their original occupation. Pain and mood disorders mainly influenced patients' present general health status. According to Matta criterion for fracture reduction, the results were excellent in 14 cases, good in 4 cases and fair in 1 case. Complications were noted as wound healing problems (26%), implant loosening (5%) and iatrogenic nerve injury (5%).

CONCLUSION

Bilateral TOS demonstrates satisfactory functional and radiological outcomes with low complication rates except infection rate in patients with traumatic spinopelvic dissociation. HRQoL is mainly dominated by pain and mood disorders. 78.9% of the patients turned back to their original occupation. Surgeons should be aware of wound healing problems in case of increased muscle mobilization and degloving injuries.Implant removal is required to improve the lumbopelvic mobility.

Minimally Invasive Percutaneous Modified Iliac Screw Placement Using Intraoperative Navigation: A Technical Note

OBJECTIVE

The modified iliac screw fixation technique was proposed to be an interesting alternative option for spinopelvic fixation. In this study, we describe a new minimally invasive technique for percutaneous placement of modified iliac screws.

METHODS

A 64-year-old man with ankylosing spondylitis suffered from a 3-column fracture at the L5 vertebra without any neurologic deficit. We performed percutaneous pedicle screw fixation from L2 to S1 with additional modified iliac screws augmentation using an intraoperative navigation. We inserted both S1 pedicle screw and modified iliac screw within a stab incision on each side of the patient's back without using rod connector.

RESULTS

The patient's severe low back pain subsided on the day following the operation. There was no clinical low back pain at 2-week follow-up. The 1-year follow-up x-ray showed that the fracture was healed successfully without signs of screw loosening or breakage.

CONCLUSIONS

The modified iliac screws can be placed safely via percutaneous approach with an intraoperative image guidance. By using this new technique, surgeons can easily adjust the screw head to align with S1 pedicle screw via the same small incision. The rod connectors are not necessary for this technique. This method also prevents the acute angle that can develop between the screw head and shaft of the screw, which is typically found in S2 alar-iliac screw technique.

Complex Fractures of the Sacrum with Spinopelvic Dissociation Treated Surgically with Iliolumbar Fixation

Objective  To analyze a series of cases of complex fractures of the sacrum with spinopelvic dissociation surgically treated with iliolumbar fixation, and to review the existing medical literature. Methods  For the analysis, the medical records of the cases operated using the Schildhauer et al technique for fixation were retrospectively evaluated, and followed up for at least 12 months. The functional results were assessed using the visual analog scale (VAS) for pain and the Oswestry disability index, version 2.0. The data were compared with those of the existing medical literature. Results  Six cases were analyzed, four of which evolved with moderate disability, one, with minimal disability, and one, with severe disability. Three cases that presented neurological deficits obtained significant improvement. Only one case evolved with pulmonary thromboembolic complications. Conclusion  The Schildhauer et al technique is an efficient technique for the fixation of complex sacral fractures with spinopelvic dissociation. The patients evolved with good functional results. Early weight-bearing has been shown to be safe with the use of this treatment.