[Intraoperative slide rail CT assistance in percutaneous sacroiliac joint screws for the treatment of pelvic posterior ring injury].

OBJECTIVE: To compare the clinical efficacy of intraoperative slide rail CT combined with C-arm X-ray assistance and just C-arm for percutaneous screw in the treatment of pelvic posterior ring injury. METHODS: A retrospective analysis was performed on the patient data of 76 patients with posterior pelvic ring injury admitted to the Department of Orthopedic Trauma from December 2018 to February 2022. Among them, 39 patients in the CT group were treated with C-arm combined with slide rail CT-assisted inline fixation including 23 males and 16 females with an average age of (44.98±7.33) years old;and the other 37 patients in the C-arm group were treated with intraline fixation treatment under only C-arm fluoroscopy including 24 males and 13 females with an average age of (44.37±10.82) years old. Among them, 42 patients with anterior ring fractures were treated with percutaneous inferior iliac spines with internal fixation (INFIX) or suprapubic support screws to fix the anterior pelvic ring. Postoperative follow-up time, operation time, complications of the two groups were compared. Results of Matta reduction criteria, Majed efficacy evaluation, the CT grading and the rate of secondary surgical revision were compared. RESULTS: The nailing time of (32.63±7.33) min in CT group was shorter than that of (52.95±10.64) min in C-arm group (t=-9.739, P<0.05). The follow-up time between CT group (11.97±1.86) months and C-arm group (12.03±1.71) months were not statistically significant(P>0.05). The postoperative complication rates between two groups were not statistically significant (χ2=0.159, P>0.05). Results of Matta reduction criteria (Z=2.79, P<0.05), Majeed efficacy evaluation(Z=2.79, P<0.05), CT grading (Z=2.83, P<0.05) in CT group were better than those in C-arm group(P<0.05); the secondary surgical revision rate in the CT group was significantly lower than that in the C-arm group (χ2=5.641, P<0.05). CONCLUSION: Compared with traditional C-arm fluoroscopy, intraoperative slide rail CT combined with C-arm assisted percutaneous sacroiliac joint screw placement surgery has the characteristics of short operation time, high accuracy and safety, and significant decrease in postoperative secondary revision rate, and is one of the effective methods for re-establishing the stability of the posterior ring of pelvic fracture.

Critical distance of the sacroiliac joint for open reduction using screw fixation for traumatic sacroiliac joint diastasis: a retrospective study.

BACKGROUND: Osteosynthesis for sacroiliac joint (SIJ) diastasis using an iliosacral screw (ISS) and a trans-iliac-trans-sacral screw (TITSS) can be performed using a closed or an open method. However, no clear indication for open reduction has been established. METHODS: Data on patients with unilateral traumatic SIJ diastasis who underwent ISS and TITSS fixation were retrospectively collected and separated into groups according to the reduction method: closed reduction group (C group) and open reduction group (O group). Demographic data and perioperative image assessments were compared between the groups. The critical distance of the SIJ was identified to elucidate the indication for open reduction of the diastatic SIJ. RESULTS: Fifty-six patients met the inclusion criteria over a 3-year period. There was no significant difference in the reduction quality of pelvic ring injuries between the groups, according to Matta's and Lefaivre's criteria. The improvement in the SIJ distance was significantly greater in the O group than in the C group in the axial plane on multiplanar computed tomography (p = 0.021). This model predicted that a difference of > 3.71 mm between the injured and healthy SIJ was a recommended indication for open reduction, with an area under the curve of 0.791 (95% confidence interval 0.627-0.955, p = 0.004). CONCLUSIONS: Open reduction for SIJ diastasis might achieve better reduction quality than does closed reduction in the axial plane in selected cases. When the difference between the injured and healthy SIJ was wider than 3.71 mm, open reduction was recommended for satisfactory radiological outcomes.

Extra-articular screw placement strategy in Stoppa approach based on three-dimensional reconstruction model.

The study aimed to explore an extra-articular screw placement strategy in Stoppa approach. Radiographic data of patients who underwent pelvic computed tomography from January 2016 to June 2017 were imported into Materiaise's interactive medical image control system software for three-dimensional reconstruction. Superior and lower margins of acetabulum and ipsilateral pelvic brim could be observed simultaneously through inlet-obturator view. A horizontal line from superior acetabular margin intersected pelvic brim at point "A" and another vertical line from lower margin intersected pelvic brim at point "B" were drawn, respectively. Lengths form sacroiliac joint to "A" (a), "A" to "B" (b), and "B" to pubic symphysis (c) were measured. Patients were divided into four groups depending on gender and side difference of measured hemi-pelvis: male left, male right, female left, and female right. Lengths of adjacent holes (d) and spanning different holes (e) of different plates were also measured. Mean lengths of a, b, c in four groups were 40.94 ± 1.85 mm, 40.09 ± 1.93 mm, 41.78 ± 3.62 mm, and 39.77 ± 2.23 mm (P = 0.078); 40.65 ± 1.58 mm, 41.48 ± 1.64 mm, 40.40 ± 1.96 mm, and 40.66 ± 1.70 mm (P = 0.265); 57.03 ± 3.41 mm, 57.51 ± 3.71 mm, 57.84 ± 4.40 mm, and 59.84 ± 4.35 mm (P = 0.165), respectively. Mean d length of different plates was 12.23 mm. Average lengths spanning 1, 2, 3 and 4 holes were 19.33 mm, 31.58 mm, 43.80 mm, and 55.93 mm. Our data showed that zones a and c could be safely inserted three and four screws. Penetration into hip joint could be avoided when vacant 3-hole drilling was conducted in zone b. Fracture line in zone b could serve as a landmark for screw placement.

Systematic Review and Meta-Analysis of the Effectiveness of Radiofrequency Ablation of the Sacroiliac Joint.

PURPOSE OF REVIEW: To evaluate the effectiveness of radiofrequency neurotomy in managing sacroiliac joint pain utilizing a systematic review with meta-analysis of randomized controlled trials (RCTs) and observational studies. RECENT FINDINGS: The prevalence of sacroiliac joint pain is estimated at around 25% of low back pain cases, and its diagnosis lacks a gold standard. Treatments include exercise therapy, injections, ablation, and fusion, with variable effectiveness. COVID-19 altered utilization patterns of interventions, including sacroiliac joint procedures, and the evidence for these interventions remains inconclusive. Recently, Medicare has issued its local coverage determinations (LCDs) in the United States, which provides noncoverage of sacroiliac joint radiofrequency neurotomy. Additionally, a recent systematic review of sacroiliac joint injections showed Level III or fair evidence. The sacroiliac joint, a critical axial joint linking the spine and pelvis, contributes to low back pain. Its complex innervation pattern varies among individuals. Sacroiliac joint dysfunction, causing pain and stiffness, arises from diverse factors.The present systematic review and meta-analysis aimed to evaluate radiofrequency neurotomy's effectiveness for sacroiliac joint pain management by applying rigorous methodology, considering both RCTs and observational studies. Despite methodological disparities, the evidence from this review, supported by changes in pain scores and functional improvement, suggests Level III evidence with fair recommendation for radiofrequency neurotomy as a treatment option. The review's strengths include its comprehensive approach and quality assessment. However, limitations persist, including variations in criteria and technical factors, underscoring the need for further high-quality studies in real-world scenarios.

Hydroxyapatite-Coated Screws Versus Titanium Triangular Dowels for Sacroiliac Joint Fusion: Results From a Nonrandomized Prospective Outcome Study.

OBJECTIVE: This is a single-surgeon series that prospectively evaluates the results of sacroiliac joint (SIJ) fusion for patients with SIJ dysfunction using hydroxyapatite-coated screws (HACSs) compared with titanium triangular dowels (TTDs). METHODS: A total of 113 patients underwent SIJ fusion surgery between 2013 and 2018 at the University Hospital Llandough to treat symptomatic SIJ dysfunction not responding to nonoperative measures. Of the 113 patients, 40 were treated with HACSs and 73 with TTDs. Patient-reported outcomes measures (PROMs) were collected preoperatively and at 12 months postoperatively, including the 36-item short-form health survey, Oswestry disability index, EuroQol-5D-5L, and Majeed pelvic score. Patients with ongoing symptoms were followed up beyond the study period. RESULTS: Of the 113 patients, 33 completed follow-up in the HACS group compared with 61 in the TTD group. Both groups had comparable preoperative PROMs; however, the postoperative PROMs were significantly better in the TTD group. Additionally, 21 patients (63%) in the HACS group had radiological evidence of screw lysis compared with 5 patients (9%) in the TTD group. A subgroup analysis revealed less significant improvement in PROMs for patients with screw lysis compared with those without. Four patients were offered further revision surgery. CONCLUSIONS: Minimally invasive SIJ fusion has been shown to have good clinical outcomes for select patients. However, our experience shows that HACSs are associated with a high rate of screw lysis and poorer patient outcomes compared with TTDs. Therefore, we recommend the use of TTDs instead of HACSs for SIJ fusion surgery.

Navigated Simultaneous Lateral Minimally Invasive Tubular and Posterior Mini-Open Access for Removal and Revision of Triangular Sacroiliac Joint Implants: A Technical Note.

BACKGROUND: Sacroiliac joint (SIJ) fusion, to treat back pain caused by SIJ dysfunction, can employ open or minimally invasive surgery (MIS) techniques and either cylindrical (screw-shaped) or triangular (wedge-shaped) implants. Fusion nonunion sometimes explains recurrent SIJ pain following fusion and occasionally requires hardware revision. MIS revision minimizes patient pain, infection, and disability, but due to the triangular implant size and form factor, implant removal can present challenges for MIS access during the explantation and achieving good bony purchase for reinstrumentation. Here, we report a prone single-position lateral MIS/posterior mini-open procedure for triangular-implant SIJ fusion revision. METHODS: The patient is a 72-year-old female who underwent right SIJ fusion for lower back and leg pain sustained after a fall 2 years prior but experienced recurrent pain over the subsequent 2 years, with imaging findings of right SIJ peri-hardware lucencies and diagnostic injections confirming persistent right-sided sacroiliitis. RESULTS: The patient underwent hardware removal using the lateral MIS incision with table-mounted tubular access and image-guided navigation to maintain exposure, plus simultaneous reinstrumentation using a navigated S2-alar-iliac screw and iliac bolt construct with connecting rod through the posterior mini-open incision made for the navigation reference frame spinous process clamp. CONCLUSIONS: The use of navigation and MIS access can significantly decrease the complexity of lateral hardware removal, and mini-open navigated screw-and-rod constructs offer reinstrumentation options accessible to surgeons unfamiliar with specialized posterior SIJ systems.

The Sacroiliac Joint: A Current State-of-the-Art Review.

¼ The sacroiliac joint (SIJ) is a common cause of low back pain and should be included in the differential diagnosis.¼ Nonoperative treatment of sacroiliac pain is always the first line of therapy; however, when it is unsuccessful and becomes chronic, then recurrent nonoperative treatment becomes expensive.¼ Surgical treatment is cost-effective in appropriately selected patients. High-quality clinical trials have demonstrated statistically and clinically significant improvement compared with nonsurgical management in appropriately selected patients.¼ Spinal fusion to the sacrum increases degeneration of the SIJ and frequency of SIJ pain.

Hip-sacroiliac joint-spine syndrome in total hip arthroplasty patients.

This study is designed to compare the extent of sacroiliac joint (SIJ) degeneration at total hip arthroplasty (THA) for two pathologies: osteoarthritis of the hip (OA) and osteonecrosis of the femoral head (ON). We also assessed the prevalence of SIJ degeneration in patients with lumbar spondylolisthesis or degenerative scoliosis. A total of 138 hips from 138 patients (69 OA and 69 ON) were assessed in this study, including 66 hips affected by OA secondary to developmental dysplasia of the hip. The degenerative changes in the SIJ and lumbar spine were evaluated prior to THA using radiographs and computed tomography (CT) scans, showing 9 instances of spondylolisthesis and 38 of degenerative scoliosis. The OA group exhibited longer duration from onset to surgery than the ON group. The OA group also included more cases with significant pelvic obliquity (3 degrees or more) and with significant increases in SIJ sclerosis and irregularities. Patients with lumbar spondylolisthesis or degenerative scoliosis were significantly more likely to have SIJ irregularities. The prevalence of SIJ degeneration was higher in cases of THA for OA than for ON. This study also suggests the possibility of Hip-SIJ-Spine syndrome in THA patients with OA.

Effect of revision sacroiliac joint fusion on unresolved pain and disability: a retrospective cohort study.

PURPOSE: The sacroiliac (SI) joint is recognized as a source of low back pain in 15-30% of patients. Though randomized controlled trials have shown clinical improvement following SI joint fusion in 83.1% of patients, revision rates of 2.9% within 2 years have been reported. There is a paucity of literature reviewing this small yet significant population of patients requiring revision surgery. METHODS: Following IRB approval, retrospective review of patients, who underwent a revision SI joint fusion from 2009 to 2021 was completed. Patient-reported outcomes were measured before and at each clinic visit after surgery with visual analoge scale (VAS) for back pain and Oswestry Disability Index (ODI). Patient characteristics (chronic opiate use and prior lumbar fusion) and surgical factors (operative approach, type/number of implants and use of bone graft) were recorded. Patient-reported outcomes were evaluated with Paired t and Wilcoxon signed rank tests. Univariate and multivariate logistic regression determined if patients met the minimally clinical important differences (MCID) for VAS-back pain and ODI scores at 1 year. RESULTS: Fifty-two patients (77% female) with an average age of 49.1 (SD ± 11.1) years met inclusion criteria. Forty-four had single sided revisions and eight bilateral revisions. At 1 year follow-up there was no significant improvement in VAS-Back (p = 0.06) or ODI (p = 0.06). Patients with chronic opioid use were 8.5 times less likely to achieve the MDC for ODI scores (OR 0.118, p = 0.029). There was no difference in outcomes when comparing the different surgical approaches (p = 0.41). CONCLUSION: Our study demonstrates patients undergoing revision surgery have moderate improvement in low back pain, however, few have complete resolution of their symptoms. Specific patient factors, such as chronic opiate use and female sex may decrease the expected improvement in patient-reported outcomes following surgery. Failure to obtain relief may be due to incorrect indications, lack of biologic fusion and/or presence of co-pathologies. Further clinical examination and consistent long-term follow-up, clarify the role revision surgery plays in long-term patient outcomes.

A systematic review and update on diagnosis and treatment of new onset sacroiliac joint dysfunction after lumbar fusion.

BACKGROUND: Sacroiliac joint dysfunction (SIJD) after lumbar/lumbosacral fusion has become increasingly recognized as the utilization of lumbar fusion has grown. Despite the significant morbidity associated with this condition, uncertainty regarding its diagnosis and treatment remains. We aim to update the current knowledge of the etiology, diagnosis, and treatment of post-lumbar surgery SIJD. METHODS: PRISMA guidelines were used to search the PubMed/Medline, Web of Science, Cochrane Reviews, Embase, and OVID databases for literature published in the last 10 years. The ROBIS tool was utilized for risk of bias assessment. Statistical analyses were performed using the R foundation. A Fisher's exact test was performed to determine the risk of SIJD based on operative technique, gender, and symptom onset timeline. Odds ratios were reported with 95% confidence intervals. A p-value [Formula: see text] 0.05 was considered statistically significant. RESULTS: Seventeen publications were included. The incidence of new onset SIJD was 7.0%. The mean age was 56 years, and the follow-up length was 30 months. SIJD was more common with fixed lumbar fusion vs floating fusion (OR = 1.48 [0.92, 2.37], p = 0.083), fusion of [Formula: see text] 3 segments (p < 0.05), and male gender increased incidence of SIJD (OR = 1.93 [1.27, 2.98], p = 0.001). Intra-articular injection decreased the Visual Analogue Scale (VAS) score by 75%, while radiofrequency ablation (RFA) reduced the score by 90%. An open approach resulted in a 13% reduction in VAS score versus 68 and 29% for SIJ fixation using the iFuse and DIANA approaches, respectively. CONCLUSIONS: Lumbar fusion predisposes patients to SIJD, likely through manipulation of the SIJ's biomechanics. Definitive diagnosis of SIJD remains multifaceted and a newer modality such as SPECT/CT may find a future role. When conservative measures are ineffective, RFA and SIJ fixation using the iFuse System yield the greatest improvement VAS and ODI.

Fluoroscopically-assisted closed reduction and percutaneous fixation of sacroiliac luxations in cats using 2.4 mm headless cannulated compression screws: Description, evaluation and clinical outcome.

OBJECTIVE: To describe fluoroscopically-assisted closed reduction and percutaneous fixation of sacroiliac-luxation (SIL) in cats and report radiographic results and long-term functional outcomes. STUDY DESIGN: Retrospective clinical study. ANIMALS: Eleven cats. METHODS: Percutaneous fixation of 17 SILs in 11 cats was performed with 2.4 mm headless cannulated compression screws under fluoroscopic guidance. Luxation-reduction, screw placement and purchase within the sacral body, pelvic canal diameter ratio (PCDR) and hemipelvic canal width ratio (HCWR) were assessed on pre- and postoperative radiographs. Radiographic follow-up was performed to assess the same parameters when available. Long-term clinical outcome was evaluated with an owner questionnaire. Wilcoxon paired-test was performed for comparison. RESULTS: Mean age and bodyweight of the cats were 3.3 ± 2.6 years and 4.0 ± 0.82 kg, respectively. Nine cats presented with concurrent pelvic injuries. Median luxation-reduction was 94.1% (IQR = 13.9) and median screw-purchase within the sacral body was 73.3% (IQR = 17.0) immediately postoperatively. One screw exited the sacral body caudally. Upon 7-week radiographic follow-up, luxation-reduction (88.3%, IQR = 20.1) and screw-purchase (70.7%, IQR = 12.8) had decreased compared to immediately postoperatively (p = .008 and p = .013 respectively). Screw migration was not observed. PCDR and HCWR measured on postoperative radiographs indicated successful restoration of the pelvic canal width. Owners reported an excellent long-term functional outcome (mean postoperative time: 19 ± 5 months). CONCLUSION: Fluoroscopically-assisted closed reduction and fixation of feline SIL using 2.4 mm headless cannulated compression screws allowed good reduction and optimal screw purchase within the sacral body. An excellent functional outcome was reported. CLINICAL SIGNIFICANCE: Minimally invasive reduction and fixation with headless compression screws should be considered in cats with SIL.

Minimally invasive sacroiliac joint fusion using triangular titanium implants versus nonsurgical management for sacroiliac joint dysfunction: a systematic review and meta-analysis.

BACKGROUND: Minimally invasive sacroiliac joint (MISIJ) fusion is a surgical option to relieve SIJ pain. The aim of this systematic review and meta-analysis was to compare MISIJ fusion with triangular titanium implants (TTI) to nonoperative management of SIJ dysfunction. METHODS: We searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials. We included prospective clinical trials that compared MISIJ fusion to nonoperative management in individuals with chronic low back pain attributed to SIJ dysfunction. We evaluated pain on visual analogue scale, Oswestry Disability Index (ODI) score, health-related quality of life (HRQoL) using the 36-Item Short Form Health Survey (SF-36) physical component (PCS) and mental component summary (MCS) scores, patient satisfaction, and adverse events. RESULTS: A total of 8 articles representing 3 trials that enrolled 423 participants were deemed eligible. There was a significant reduction in pain score with MISIJ fusion compared with nonoperative management (standardized mean difference [SMD] -1.71, 95% confidence interval [CI] -2.03 to -1.39). Similarly, ODI scores (SMD -1.03, 95% CI -1.24 to -0.81), SF-36 PCS scores (SMD 1.01, 95% CI 0.83 to 1.19), SF-36 MCS scores (SMD 0.72, 95% CI 0.54 to 0.9), and patient satisfaction (odds ratio 6.87, 95% CI 3.73 to 12.64) were significantly improved with MISIJ fusion. No significant difference was found between the 2 groups with respect to adverse events (SMD -0.03, 95% CI -0.28 to 0.23). CONCLUSION: Our analysis showed that MISIJ fusion with TTI shows a clinically important and statistically significant improvement in pain, disability score, HRQoL, and patient satisfaction with a similar adverse event profile to nonoperative management in patients with chronic low back pain attributed to SIJ dysfunction.

The Effects of Abdominal Obesity and Sagittal Imbalance on Sacroiliac Joint Pain After Lumbar Fusion.

BACKGROUND: Postoperative sacroiliac joint pain (SIJP) is a common manifestation of failed back surgery syndrome after a posterior lumbar interbody fusion (PLIF). However, there is currently no consensus on the risk factors for SIJP after PLIF. OBJECTIVES: We explored the effects of abdominal obesity and sagittal imbalance on SIJP after PLIF. STUDY DESIGN: This is a prospective observational cohort study. SETTING: This study occurred at the Department of Spinal Surgery at a hospital affiliated with a medical university. METHODS: A total of 401 patients who underwent PLIF from June 2018 to June 2021 were enrolled in this study. 36 patients experienced postoperative SIJP. In contrast, a matched group comprised 72 non-SIJP patients. We used 1:2 propensity score matching to compare obesity features and sagittal spine parameters in the 2 groups. Inflammatory cytokines and visual analog scale (VAS) scores were measured in the SIJP group. RESULTS: A total of 36 patients (8.98%) experienced SIJP during the follow-up. Compared with the non-SIJP group, patients with postoperative SIJP had a higher body mass index (BMI), greater abdominal obesity, a higher incidence of pelvic incidence-lumbar lordosis greater than 10°, and a higher incidence of a sagittal vertical axis greater than 5 cm (P < 0.05). Receiver operating characteristic curve analysis showed that the area under the curve for waist circumference was greater than that for BMI (0.762 vs. 0.650, P = 0.049). Logistic regression analysis revealed that the risk factors for SIJP were abdominal obesity, a pelvic incidence-lumbar lordosis of greater than 10°, and a sagittal vertical axis greater than 5 cm (P < 0.05). In patients with SIJP, interleukin 6, tumor necrosis factor-α, and VAS scores were higher in the abdominal obesity group than in the non-abdominal obesity group (P < 0.05). LIMITATIONS: There was no uniform diagnosis of SIJP, so the incidence rate of SIJP might not be accurate. CONCLUSIONS: The significant predictors of SIJP were abdominal obesity and sagittal imbalance. Patients with abdominal obesity showed higher levels of inflammatory markers and pain intensity. More attention should be paid to body shape and the angle of correction of lumbar lordosis before lumbar surgery.

Patient-Reported Outcomes and Computed Tomography Review After Minimally Invasive Fusion of the Sacroiliac Joint With Aggressive Joint Decortication and Joint Compression.

The sacroiliac joint (SIJ) is a common, underrecognized source of low back pain. We evaluated outcomes in patients undergoing sacroiliac joint fusion (SIJF) using a novel, minimally invasive SIJF system emphasizing compressive forces across an aggressively debrided SIJ. We retrospectively reviewed data from a continuous set of patients presenting to a large, tertiary care hospital from September 2017 to August 2019. All patients received the novel SIJF device. Outcomes were assessed at 8 weeks, 6 months, and 12 months using the Oswestry Disability Index (ODI) score, Numerical Rating Scale (NRS) score, Single Assessment Numerical Evaluation (SANE) score, and Patient-Reported Outcomes Measurement Information System (PROMIS) measures, plus radiographic evaluation of fusion status. Data from 75 patients were analyzed. At 8 weeks, 6 months, and 12 months, the ODI score improved by 10.5 points (P=.002), 17.4 points (P<.0001), and 23.6 points (P<.0001), respectively, while the NRS score improved by 4.6 points (P<.0001), 4.4 points (P<.0001), and 4.6 points (P<.0001), respectively. SANE scores indicated high levels of patient satisfaction (81.0%, 92.18%, and 89.2%, respectively). PROMIS physical function scores improved by 2.65 points, 3.30 points, and 3.63 points, respectively, while PROMIS mental health scores showed changes of -1.93 points, 1.57 points, and -0.47 points, respectively. A review of computed tomography scans demonstrated grade 3 fusion (complete) in 81% of cases at a mean of 371 days postoperatively. There was one revision case for a malpositioned implant. The use of a novel SIJF device emphasizing compressive forces provided early, durable improvements in patient-reported outcomes and extremely high patient satisfaction. [Orthopedics. 2024;47(2):101-107.].

Cooled radiofrequency ablation versus standard medical management for chronic sacroiliac joint pain: a multicenter, randomized comparative effectiveness study.

INTRODUCTION: Low back pain is the leading cause of disability worldwide, with sacroiliac joint pain comprising up to 30% of cases of axial lower back pain. Conservative therapies provide only modest relief. Although placebo-controlled trials show efficacy for sacral lateral branch cooled radiofrequency ablation, there are no comparative effectiveness studies. METHODS: In this randomized, multicenter comparative effectiveness study, 210 patients with clinically suspected sacroiliac joint pain who obtained short-term benefit from diagnostic sacroiliac joint injections and prognostic lateral branch blocks were randomly assigned to receive cooled radiofrequency ablation of the L5 dorsal ramus and S1-S3 lateral branches or standard medical management consisting of pharmacotherapy, injections and integrative therapies. The primary outcome measure was mean reduction in low back pain score on a 0-10 Numeric Rating Scale at 3 months. Secondary outcomes included measures of quality of life and function. RESULTS: 3 months post-treatment, the mean Numeric Rating Scale pain score for the cooled radiofrequency ablation group was 3.8±2.4 (mean reduction 2.5±2.5) compared with 5.9±1.7 (mean reduction 0.4±1.7) in the standard medical management group (p<0.0001). 52.3% of subjects in the cooled radiofrequency ablation group experienced >2 points or 30% pain relief and were deemed responders versus 4.3% of standard medical management patients (p<0.0001). Comparable improvements favoring cooled radiofrequency ablation were noted in Oswestry Disability Index score (mean 29.7±15.2 vs 41.5+13.6; p<0.0001) and quality of life (mean EuroQoL-5 score 0.68±0.22 vs 0.47±0.29; p<0.0001). CONCLUSIONS: In patients with sacroiliac joint pain, cooled radiofrequency ablation provided statistically superior improvements across the spectrum of patient outcomes compared with standard medical management. TRIAL REGISTRATION NUMBER: NCT03601949.

Return to Duty in Military Service Members Following Minimally Invasive Sacroiliac Joint Fusion.

INTRODUCTION: As the utilization of minimally invasive sacroiliac joint fusion (SIJF) continues to expand, a better understanding of postoperative outcomes is needed, particularly in young and active individuals. The purpose of this study is to assess the outcomes of this procedure in an active duty military population by examining return-to-duty (RTD) rates. MATERIALS AND METHODS: A retrospective review of the electronic medical record from a tertiary military medical center was performed for active duty service members undergoing SIJF from January 2013 to January 2019. The primary outcome measured was RTD at 6 months, with active duty status at 1 year, last follow-up, and revision surgery as secondary outcomes. Demographic and surgical variables recorded included patient age, gender, military rank, utilization of navigation, and implant type. RESULTS: Sixteen service members met the inclusion criteria, with a mean age of 40.5 ± 6.7 years. The mean follow-up after surgery was 24 ± 15 months. Patients received either cylindrical (n = 6) or triangular (n = 10) implants placed with (n = 6) or without (n = 10) navigation. Within 6 months of surgery, 56% of patients were able to RTD. Patients undergoing navigation-assisted procedures were significantly more likely to RTD at 6 months (100% vs. 30%, P = .011) compared to those undergoing surgery performed with orthogonal fluoroscopic imaging. Compared to those with cylindrical implants, patients with triangular implants were also more likely to RTD at 6 months (80% vs. 17%, P = .035). CONCLUSIONS: Following SIJF, a small majority of service members were able to return to full active duty status by 6 months. Further studies are needed to assess the potential benefits of navigation and implant selection, as our retrospective review noted differences in outcomes based on these variables.

Biomechanical Comparison of Double 2.3-mm Headless Cannulated Self-Compression Screws and Single 3.5-mm Cortical Screw in Lag Fashion in a Canine Sacroiliac Luxation Model: A Small Dog Cadaveric Study.

OBJECTIVE: The aim of this study was to evaluate the feasibility of safe positioning of double 2.3-mm headless cannulated self-compression screws (HCS) in a small dog cadaveric sacroiliac luxation model and to compare the static rotational biomechanical properties of fixation repaired using two different screw systems with a minimally invasive osteosynthesis technique: double 2.3-mm HCS and a single 3.5-mm standard cortical screw placed in a lag fashion. STUDY DESIGN: A unilateral small dog sacroiliac luxation model was stabilized using double 2.3-mm HCS (n = 11) or a single 3.5-mm cortical screw (n = 11). Radiographic and computed tomography (CT) imaging analyses and biomechanical testing of rotational force on the sacroiliac joint of both fixations were performed. The maximum load at failure and failure modes of each fixation were recorded and compared. RESULTS: Fluoroscopically guided percutaneous application of double HCS was safe in a unilateral sacroiliac luxation model in small dogs without violation of the vertebral and ventral sacral foramen. Furthermore, resistance to rotational force applied on fixation of the sacroiliac joint repaired with double 2.3-mm HCS estimated by maximum failure load was significantly higher than that of a single 3.5-mm cortical screw (p < 0.001). CONCLUSION: Although this was an experimental cadaveric study, based on our results, the use of smaller double HCS may be beneficial as an alternative to the conventional single lag screw for stabilization of sacroiliac luxation in small dogs.

Evolving Trends in the Use of Sacroiliac Fusion From 2015 to 2020.

STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: To assess the evolution of patients undergoing sacroiliac (SI) fusion with minimally invasive surgery (MIS) relative to open approaches. SUMMARY OF BACKGROUND DATA: The SI joint can be a contributor to lumbopelvic symptoms. The MIS approach to SI fusion has been shown to have fewer complications compared with the open approach. Recent trends and evolved patient populations have not been well-characterized. MATERIALS AND METHODS: Data were abstracted from the large, national, multi-insurance, administrative 2015-2020 M151 PearlDiver database. The incidence, trends, and patient characteristics of MIS, as well as open, SI fusions for adult patients with degenerative indications, were determined. Univariable and multivariable analyses were then performed to compare the MIS relative to open populations. The primary outcome was to assess the trends of MIS and open approaches for SI fusions. RESULTS: In total, 11,217 SI fusions were identified (of which 81.7% were MIS), with a clear increase in numbers over the years from 2015 (n=1318, 62.3% of which were MIS) to 2020 (n=3214 86.6% of which were MIS). Independent predictors of MIS (as opposed to open) SI fusion included: older age (odds ratio [OR] 1.09 per decade increase), higher Elixhauser-Comorbidity Index (OR 1.04 per two-point increase), and geographic region (relative to South, Northeast OR 1.20 and West OR 1.64). As might be expected, 90-day adverse events were lower for MIS than open cases (OR 0.73). CONCLUSION: The presented data quantify the increasing incidence of SI fusions over the years, with the increase being driven by MIS cases. This was largely related to an expanded population (those who are older and with greater comorbidity), fitting the definition of disruptive technology with lesser adverse events than open procedures. Nonetheless, geographic variation highlights the differential adoption of this technology.

Comparison of the operation safety and biomechanical stability of sacral alar-iliac vs. sacroiliac screws in the fixation of sacroiliac joint in simulated models of low bone density.

BACKGROUND: Sacral alar-iliac screws (SAISs) have been used for sacroiliac joint and are superiority to traditional sacroiliac screws (SISs) in patients with low bone density. The aim of this study was to investigate the operation safety and biomechanical stability of the SIS, transsacral-transiliac screw (TSTIS), S1AIS and S2AIS in the treatment of sacroiliac joint in simulated models of low bone density. METHODS: CT data from 80 normal pelvic structures were employed to measure the anatomical parameters, including the safety zones of the S1AIS and S2AIS at the insertion point and the trajectory lengths of the SIS, TSTIS, S1AIS and S2AIS. Sixteen synthetic pelvises with simulated osteoporotic bone structure were used to simulate type C Tile lesions and divided into 4 groups with an anterior plate and posterior fixation using one of the following: 1) one SIS on each side, 2) one TSTIS fixing both sides, 3) one S1AIS on each side, or 4) one S2AIS on each side. The stiffness and maximum load of the specimens were analyzed using a biomechanical machine under vertical loading. RESULTS: The safety zone of S1AIS was larger than that of S2AIS (p < 0.05). The TSTIS had the largest trajectory length, followed by the S1AIS and S2AIS, and the SIS had the smallest trajectory length (p < 0.05). However, the lengths of the TSTIS (26.1 ± 1.7 mm) and SIS (27.8 ± 1.8 mm) trajectories on the short side (the iliac side) were smaller than those of S1AIS (40.4 ± 3.8 mm) and S2AIS (39.1 ± 3.8 mm), thus indicating significant differences (p < 0.05). The stiffness and maximum load of S1AIS and S2AIS were similar and the greatest, followed by TSTIS and SIS (p < 0.05). CONCLUSION: The stability of S1AIS and S2AIS is similar, both stronger than that of SIS and TSTIS, which have shorter lengths of the screw trajectories on the ilium side. However, the safety zone of S2AIS at the insertion point is smaller than that of S1AIS. Therefore, considering both safety and stability, S1AIS is the preferred choice for fixation of sacroiliac joint dislocation in simulated models of low bone density.

Ideal insertion point and projection of the infra-acetabular screw in acetabular fracture surgery.

BACKGROUND: In acetabular fracture surgery, an infra-acetabular screw (IAS) is inserted from the anterior to the posterior column through the infra-acetabular corridor to stabilize both columns. Although the IAS is useful for increasing fixation strength, proper placement requires proficiency and often results in extraosseous screw penetration. The complex anatomy of the infra-acetabular corridor and difficult intraoperative detection of the ideal insertion point and angle make proper placement of the IAS challenging. This study aimed to detect the ideal insertion point and angle of the IAS based on anatomical landmarks that can be directly identified intraoperatively. METHODS: We retrospectively reviewed the pelvic CT of 50 adults who underwent serial slice CT imaging. The pelvic inlet plane (PIP), which contains the anterior border of both the sacroiliac joint and posterior superior edge of the pubic symphysis, was used as the reference plane for the pelvic coordinate system to simulate the ideal insertion of IAS. The distance from the posterior superior edge of the pubic symphysis to the ideal insertion point of the IAS (IAS distance) and the angle and length of the IAS that could be inserted from the ideal insertion point were measured. RESULTS: The mean IAS distance was 61.0 ± 5.7 mm (57.6 ± 4.3 mm in men and 64.4 ± 4.9 mm in women). The mean angle between ideal IAS and yz-plane on the outlet view (α-angle) was 8.4 ± 6.6 ° (6.4 ± 5.6° in men and 10.5 ± 7.0° in women). The mean angle between ideal IAS and y-axis on the yz-plane (ß-angle) was 86.5 ± 10.6 ° (86.0 ± 10.3° in men and 87.0 ± 10.9° in women). The length of IAS was 97.1 ± 4.7 mm in men and 89.2 ± 3.6 mm in women. CONCLUSION: The IAS ideal insertion point detected as a distance from the pubic symphysis may aid in the proper insertion of the IAS during surgery. The insertion angle was parallel or tilted 10 ° laterally to the longitudinal axis in the pelvic outlet plane and almost perpendicular to the PIP in the sagittal plane when inserted from the ideal insertion point.