Bilateral open sacroiliac joint fusion during adult spinal deformity surgery using triangular titanium implants: technique description and presentation of 21 cases

OBJECTIVE Pelvic fixation enhances long constructs during deformity surgery. Subsequent loosening of iliac screws and pain at the pelvis occur in as many as 29% of patients. Concomitant sacroiliac (SI) fusion may prevent potential pain and failure. The objective of this study was to describe a novel surgical technique and a single institution’s experience using bilateral SI fusion during adult deformity surgery with S2-alar-iliac (S2AI) screws and triangular titanium rods (TTRs) placed with navigation. METHODS The authors reviewed open SI joint fusions with TTR performed between August 2019 and March 2020. All patients underwent lumbosacral fusion through a midline approach and bilateral S2AI pelvic fixation in the caudal teardrop, followed by TTR placement just proximal and cephalad to the S2AI screws using intraoperative CT imaging guidance. RESULTS Twenty-one patients were identified who received 42 TTRs, ranging in size from 7.0 × 65 mm to 7.0 × 90 mm. Three TTRs (7%) were malpositioned intraoperatively, and each was successfully repositioned during index surgery without negative sequelae. All breaches occurred in a medial and cephalad direction into the pelvis. Incremental operative time for adding TTR averaged 8 minutes and 33 seconds per implant. CONCLUSIONS Image-guided open SI joint fusion with TTR during lumbosacral fusion is technically feasible. The bony corridor for implant placement is narrower cephalad, and implants tend to deviate medially into the pelvis. Detection of malpositioned implant is aided with intraoperative CT, but this can be salvaged. A prospective randomized clinical trial is underway that will better inform the impact of this technique on patient outcomes.

Download Full-text

Acute failure of S2-alar-iliac screw pelvic fixation in adult spinal deformity: novel failure mechanism, case series, and review of the literature

Journal of Neurosurgery Spine ◽

10.3171/2021.2.spine201921 ◽

2021 ◽

pp. 1-9

Author(s):

Christopher T. Martin ◽

David W. Polly ◽

Kenneth J. Holton ◽

Jose E. San Miguel-Ruiz ◽

Melissa Albersheim ◽

...

Keyword(s):

Failure Mechanism ◽

Lumbar Lordosis ◽

Adult Spinal Deformity ◽

Case Series ◽

Vertical Axis ◽

Consecutive Series ◽

Adult Deformity ◽

Pelvic Fixation ◽

Fixation Points ◽

Acute Failure

OBJECTIVE Pelvic fixation with S2-alar-iliac (S2AI) screws is an established technique in adult deformity surgery. The authors’ objective was to report the incidence and risk factors for an underreported acute failure mechanism of S2AI screws. METHODS The authors retrospectively reviewed a consecutive series of ambulatory adults with fusions extending 3 or more levels, and which included S2AI screws. Acute failure of S2AI screws was defined as occurring within 6 months of the index surgery and requiring surgical revision. RESULTS Failure occurred in 6 of 125 patients (5%) and consisted of either slippage of the rods or displacement of the set screws from the S2AI tulip head, with resultant kyphotic fracture. All failures occurred within 6 weeks postoperatively. Revision with a minimum of 4 rods connecting to 4 pelvic fixation points was successful. Two of 3 (66%) patients whose revision had less fixation sustained a second failure. Patients who experienced failure were younger (56.5 years vs 65 years, p = 0.03). The magnitude of surgical correction was higher in the failure cohort (number of levels fused, change in lumbar lordosis, change in T1–pelvic angle, and change in coronal C7 vertical axis, each p < 0.05). In the multivariate analysis, younger patient age and change in lumbar lordosis were independently associated with increased failure risk (p < 0.05 for each). There was a trend toward the presence of a transitional S1–2 disc being a risk factor (OR 8.8, 95% CI 0.93–82.6). Failure incidence was the same across implant manufacturers (p = 0.3). CONCLUSIONS All failures involved large-magnitude correction and resulted from stresses that exceeded the failure loads of the set plugs in the S2AI tulip, with resultant rod displacement and kyphotic fractures. Patients with large corrections may benefit from 4 total S2AI screws at the time of the index surgery, particularly if a transitional segment is present. Salvage with a minimum of 4 rods and 4 pelvic fixation points can be successful.

Download Full-text

Six-month outcomes from a randomized controlled trial of minimally invasive SI joint fusion with triangular titanium implants vs conservative management

European Spine Journal ◽

10.1007/s00586-016-4599-9 ◽

2016 ◽

Vol 26 (3) ◽

pp. 708-719 ◽

Cited By ~ 37

Author(s):

Bengt Sturesson ◽

Djaya Kools ◽

Robert Pflugmacher ◽

Alessandro Gasbarrini ◽

Domenico Prestamburgo ◽

...

Keyword(s):

Randomized Controlled Trial ◽

Minimally Invasive ◽

Conservative Management ◽

Controlled Trial ◽

Titanium Implants ◽

Randomized Controlled ◽

Joint Fusion ◽

Si Joint

Download Full-text

Sacroiliac Joint Arthrodesis-MIS Technique with Titanium Implants: Report of the First 50 Patients and Outcomes

The Open Orthopaedics Journal ◽

10.2174/1874325001206010495 ◽

2012 ◽

Vol 6 (1) ◽

pp. 495-502 ◽

Cited By ~ 62

Author(s):

Leonard Rudolf

Keyword(s):

Sacroiliac Joint ◽

Titanium Implants ◽

Point Change ◽

Joint Fusion ◽

Sacroiliac Joint Disruption ◽

Clinically Significant ◽

Spine Surgeon ◽

Sacroiliac Joint Fusion ◽

Si Joint

This retrospective study of 50 consecutive patients treated by a single orthopedic spine surgeon in private practice was conducted to evaluate the safety and efficacy of minimally invasive sacroiliac joint fusion using a series of triangular, porous plasma spray coated titanium implants.Medical charts were reviewed for perioperative metrics, complications, pain, quality of life and satisfaction with surgery. All patients were contacted at a 24 months post-op to assess SI joint pain, satisfaction with surgery and work status.An early and sustained statistically significant improvement in pain function was identified at all post-operative time points (ANOVA, p<0.000). A clinically significant improvement (>2 point change from baseline) was observed in 7 out of 9 domains of daily living. The complication rate was low and more than 80% of patients would have the same surgery again.MIS SI joint fusion appears to be a safe and effective procedure for the treatment of sacroiliac joint disruption or degenerative sacroiliitis.

Download Full-text

5. A biomechanical investigation of the sacroiliac joint in the setting of lumbosacral fusion: the impact of pelvic fixation vs sacroiliac joint fixation

The Spine Journal ◽

10.1016/j.spinee.2019.05.018 ◽

2019 ◽

Vol 19 (9) ◽

pp. S3

Author(s):

Harry M. Mushlin ◽

Gerald Hayward ◽

Daina M. Brooks ◽

Bryan Ferrick ◽

Stephen Carbine ◽

...

Keyword(s):

Sacroiliac Joint ◽

Lumbosacral Fusion ◽

Pelvic Fixation ◽

Biomechanical Investigation ◽

The Impact

Download Full-text

Minimally Invasive Techniques for Iliac Bolt Placement: 2-Dimensional Operative Video

Operative Neurosurgery ◽

10.1093/ons/opab001 ◽

2021 ◽

Vol 20 (4) ◽

pp. E292-E292

Author(s):

Travis Hamilton ◽

Mohamed Macki ◽

Thomas M Zervos ◽

Victor Chang

Keyword(s):

Minimally Invasive ◽

Imaging System ◽

Pedicle Screws ◽

Vertical Axis ◽

Spinal Diseases ◽

Open Approach ◽

Sagittal Vertical Axis ◽

Pelvic Fixation ◽

Iliac Screws ◽

Invasive Techniques

Abstract As the popularity of minimally invasive surgery (MIS) continues to grow, novel techniques are needed to meet the demands of multisegment fixation for advanced spinal diseases. In one such example, iliac bolts are often required to anchor large fusion constructs, but MIS technical notes are missing from the literature. A 67-yr-old female presented with a symptomatic coronal deformity: preoperative pelvic incidence = 47°, pelvic tilt = 19°, and lumbar lordosis = 29°, sagittal vertical axis = +5.4 cm with 30° of scoliosis. The operative plan included T10-ilium fusion with transforaminal interbody grafts at L2-3, L3-4, L4-5, and L5-S1. The intraoperative video is of minimally invasive placement of iliac bolts using the O-Arm Surgical Imaging System (Medtronic®). The patient consented to the procedure. A mini-open exposure that remains above the fascial planes allows for multilevel instrumentation with appropriate decompression at the interbody segments. After the placement of the pedicle screws under image-guidance, the direction is turned to the minimally invasive iliac bolts. Following the trajectory described in the standard open approach,1 the posterior superior iliac spine (PSIS) is identified with the navigation probe, which will guide the Bovie cautery through the fascia. This opening assists in the trajectory of the navigated-awl tap toward the anterior superior iliac spine (ASIS). Next, 8.5 mm x 90 mm iliac screws were placed in the cannulated bone under navigation. After intraoperative image confirmation of screw placement, the contoured rods are threaded under the fascia. The setscrews lock the rod in position. MIS approaches obviate cross-linking the rods, rendering pelvic fixation more facile. This technique allows for minimal dissection of the posterior pelvic soft tissue while maintaining adequate fixation.

Download Full-text

Failure Types and Related Factors of Spinopelvic Fixation After Long Construct Fusion for Adult Spinal Deformity

Neurosurgery ◽

10.1093/neuros/nyaa469 ◽

2020 ◽

Author(s):

Se-Jun Park ◽

Jin-Sung Park ◽

Yunjin Nam ◽

Tae-Hoon Yum ◽

Youn-Taek Choi ◽

...

Keyword(s):

Risk Factors ◽

Ct Scan ◽

Spinal Deformity ◽

Adult Spinal Deformity ◽

Study Cohort ◽

Related Factors ◽

Fixation Failure ◽

Failure Group ◽

Pelvic Fixation ◽

Spinopelvic Fixation

Abstract BACKGROUND Rigid internal fixation of the spine is an essential part of adult spinal deformity (ASD) surgery. Despite the use of pelvic fixation and anterior column support, spinopelvic fixation failure (SPFF) still remains an issue. Few studies have evaluated the types of such failure or its related factors. OBJECTIVE To classify the types of SPFF and investigate its risk factors, including the fusion status at L5-S1 on CT scan. METHODS The study cohort consisted of ninety-eight ASD patients who underwent more than 4-level fusions to the sacrum with interbody fusion at L5-S1. Patients with SPFF were divided into the two groups: above-S1 and below-S1 failure groups. The patient, surgical, and radiographic variables in each group were compared to those of the no-failure group. The L5-S1 fusion status was assessed using 2-yr computed tomography (CT) scan. Univariate and multivariate analyses were performed to determine the risk factors for each failure group. RESULTS The mean age was 68.5 yr. Follow-up duration was 55.7 mo. The SPFF developed in 46 (46.9%) patients at 32.7 mo postoperatively. There were 15 patients in the above-S1 failure group and 31 patients in the below-S1 failure group. Multivariate analysis revealed that nonunion at L5-S1 was a single risk factor for above-S1 failure. In contrast, the risk factors for below-S1 failure included a greater number of fused segments and postoperative less thoracic kyphosis. CONCLUSION SPFF develops in different patterns with different risk factors. Above-S1 SPFF was associated with nonunion at L5-S1, while below-S1 SPFF was associated with mechanical stress.

Download Full-text

Is L5/S1 interbody fusion necessary in long-segment surgery for adult degenerative scoliosis? A systematic review and meta-analysis

Journal of Neurosurgery Spine ◽

10.3171/2021.9.spine21883 ◽

2021 ◽

pp. 1-8

Keyword(s):

Systematic Review ◽

Interbody Fusion ◽

Case Reports ◽

Adult Spinal Deformity ◽

Meta Analysis ◽

Lumbar Interbody Fusion ◽

Lumbosacral Junction ◽

Pelvic Fixation ◽

Group 2 ◽

Group 1

OBJECTIVE There is no consensus regarding the best surgical strategy at the lumbosacral junction (LSJ) in long constructs for adult spinal deformity (ASD). The use of interbody fusion (IF) has been advocated to increase fusion rates, with additional pelvic fixation (PF) typically recommended. The actual benefit of IF even when extending to the pelvis, however, has not been vigorously analyzed. The goal of this work was to better understand the role of IF, specifically with respect to arthrodesis, when extending long constructs to the ilium. METHODS A systematic review of the PubMed and Cochrane databases was performed to identify the relevant studies in English, addressing the management of LSJ in long constructs (defined as ≥ 5 levels) in ASD. The search terms used were as follows: “Lumbosacral Junction,” “Long Constructs,” “Long Fusion to the Sacrum,” “Sacropelvic Fixation,” “Interbody Fusion,” and “Iliac Screw.” The authors excluded technical notes, case reports, literature reviews, and cadaveric studies; pediatric populations; pathologies different from ASD; studies not using conventional techniques; and studies focused only on alignment of different levels. RESULTS The PRISMA protocol was used. The authors found 12 retrospective clinical studies with a total of 1216 patients who were sorted into 3 different categories: group 1, using PF or not (n = 6); group 2, using PF with or without IF (n = 5); and group 3, from 1 study comparing anterior lumbar interbody fusion versus transforaminal lumbar interbody fusion. Five studies in group 1 and 4 in group 2 had pseudarthrosis rate as primary outcome and were selected for a quantitative analysis. Forest plots were used to display the risk ratio, and funnel plots were used to look at the risk of publication bias. The summary risk ratios were 0.36 (0.23–0.57, p < 0.001) and 1.03 (0.54–1.96, p = 0.94) for the PF and IF, respectively; there is a protective effect of overall pseudarthrosis for using PF in long constructs for ASD surgeries, but not for using IF. CONCLUSIONS The long-held contention that L5/S1 IF is always advantageous in long-construct deformity surgery is not supported by the current literature. Based on the findings from this systematic review and meta-analysis, PF with or without additional L5/S1 interbody grafting demonstrates similar overall construct pseudarthrosis rates. The added risk and costs associated with IF, therefore, should be more closely considered on a case-by-case basis.

Download Full-text