Five-year clinical and radiographic outcomes after minimally invasive sacroiliac joint fusion using triangular implants.

OBJECT: Previous reports of minimally invasive (MIS) sacroiliac (SI) joint fusion for low back, SI joint, and buttock pain secondary to SI joint disorders have shown favorable short- and mid-term outcomes. Herein we present 5-year clinical and radiographic outcomes after MIS SI joint fusion using a series of triangular porous titanium plasma spray (TPS) coated implants. METHODS: Consecutive patients treated with MIS SI joint fusion for degenerative sacroiliitis and/or sacroiliac joint disruptions between October 2007 and March 2009 were evaluated. Pain on VAS, an SI joint specific survey and Oswestry Disability Index (ODI) were administered. X-ray and CT scans were obtained to assess the implants. RESULTS: Of 21 patients treated, 17 were available for the study. Mean age was 58 years (range 36-85), 77% were female and 47% had prior lumbar spinal fusion. Pain on VAS improved from 8.3 at baseline to 2.4 at 5 years; 88% of patients reached Substantial Clinical Benefit. Mean ODI score at 5 years was 21.5 (SD 22.7). Patient satisfaction achieved at 12 months was maintained for 5 years (82%). A qualitative review of x-ray and CT imaging showed increased bone density immediately adjacent to all implants, intra-articular osseous bridging in 87% of patients and no evidence of implant loosening or migration. CONCLUSION: Long-term clinical and radiographic outcomes after MIS SIJ fusion are favorable. Clinical improvements observed at 12 months postoperatively were maintained at 5 years. There was no evidence of long-term complications, implant loosening or migration. Patients who did not achieve large improvements were affected by multiple severe concomitant degenerative conditions of the lumbar spine, pelvis, and/or hip.

MIS Fusion of the SI Joint: Does Prior Lumbar Spinal Fusion Affect Patient Outcomes?

BACKGROUND: Sacroiliac (SI) joint pain is a challenging condition to manage as it can mimic discogenic or radicular low back pain, and present as low back, hip, groin and/or buttock pain. Patients may present with a combination of lumbar spine and SI joint symptoms, further complicating the diagnosis and treatment algorithm [1-3]. SI joint pain after lumbar spinal fusion has been reported in the literature. Both clinical and biomechanical studies show the SI joint to be susceptible to increased motion and stress at the articular surface with up to 40-75% of patients developing significant SI joint degeneration after 5 years. In a recent case series study of 50 patients who underwent minimally invasive SI joint arthrodesis, 50% had undergone previous lumbar spinal fusion and 18% had symptomatic lumbar spine pathology treated conservatively [4]. The purpose of this study is to determine if history of previous lumbar fusion or lumbar pathology affects patient outcomes after MIS SI joint fusion surgery. METHODS: We report on 40 patients with 24 month follow up treated with MIS SI joint fusion using a series of triangular porous plasma coated titanium implants (iFuse, SI-Bone, Inc. San Jose, CA). Outcomes using a numerical rating scale (NRS) for pain were obtained at 3-, 6-, 12- and 24 month follow up intervals. Additionally, patient satisfaction was collected at the latest follow up interval. Patients were separated into 3 cohorts: 1) underwent prior lumbar spine fusion (PF), 2) no history of previous lumbar spine fusion (NF), 3) no history of previous lumbar spine fusion with symptomatic lumbar spine pathology treated conservatively (LP). A repeated measures analysis of variance (rANOVA) was used to determine if the change in NRS pain scores differed across timepoints and subgroups. A decrease in NRS by 2 points was deemed clinically significant [5]. RESULTS: Mean age was 54 (±13) years and varied slightly but not statistically between groups. All subgroups experienced a clinically and statistically significant reduction in pain at all time points (mean change >2 points, p<0.001). There was a statistically significant effect of cohort (p=0.045), with the NF cohort (no prior lumbar spinal fusion) having a somewhat greater decrease in pain (by approximately 1 point) compared to the other 2 groups (PF and LP).Patient reported satisfaction by cohort was: 89% (NF), 92% (PF) and 63% (LP).Overall satisfaction rate was 87%. DISCUSSION AND CONCLUSION: Patients with SI joint pain, regardless of prior lumbar spine fusion history, show significant improvement in pain after minimally invasive SI joint fusion. The presence of symptomatic lumbar spine pathology potentially confounds the treatment affect, as patients may not be able to discriminate between symptoms arising from the SI joint and the lumbar spine. These patients expressed a lower satisfaction with surgery. Patients without other confounding lumbar spine pathology and who have not undergone previous spine surgery tend to be younger and experience a greater reduction in pain.

Outcome of percutaneous sacroiliac joint fixation with porous plasma-coated triangular titanium implants: an independent review.

DESIGN: Independent retrospective review of a single surgeon's experience with a new technique of SI fixation. OBJECTIVE: Examine results of percutaneous fixation of the SI joint with porous coated triangular titanium implants. BACKGROUND: Diagnosis and treatment of a dysfunctional sacroiliac joint is challenging as well as controversial. Recently, percutaneous stabilization techniques have been implemented for fixation. There is minimal literature published on this technique. METHODS: Charts, radiographs, and CT scans of 31 patients operated on by a single surgeon were de-identified and randomized and then reviewed by investigators not involved with the care of the patients. Reviewers had no relationship with the implant manufacturer at the time of the review. OUTCOME MEASURES: intraoperative and postoperative complication, EBL, hospital stays, postoperative image location and number of lucent implants, ingrowth into implants, and bone across SI joint. RESULTS: 27 patients expressed satisfaction, 4 patients did not. Pain relief was noted to be Complete (16 patients), Excellent (5 patients), Good (9 patients), and Fair (1 patients). Four patients had postoperative complications. These were infected hematoma (2), L5 nerve root irritation (1), and L5-S1 discitis (1). One patient required revision. On 6 month postop CT scan, 18/19 patients had radiographic evidence of bone ingrowth and bone into or across the SI joint was evident in 8/19 patients. Lucency was noted around at least one implant in 5/19 patients. CONCLUSIONS: Results are promising for the use of this novel implant for a carefully selected group of patients with disabling SI dysfunction.

Open versus minimally invasive sacroiliac joint fusion: a multi-center comparison of perioperative measures and clinical outcomes.

BACKGROUND: Sacroiliac (SI) joint pain is an under diagnosed source of low back pain due in part to lack of visible pathology on radiographs and symptoms mimicking other back-related disorders. Open SI joint fusion has been performed since the 1920s. This technique has fallen out of favor with the introduction of minimally invasive options. To date there has been no direct comparison between open and MIS SI joint fusion. METHODS: We conducted a multi-center, retrospective comparative cohort study of patients who underwent SI joint fusion using either an open surgical (OS) technique using a combination of screws and cages or a minimally invasive surgical (MIS) technique with a series of titanium plasma spray (TPS) coated triangular implants. Operative measures including surgical operating time, length of hospitalization and estimated blood loss (EBL) were collected along with demographics and medical history, surgical complications, and 12- and 24-month pain scores. Improvements in pain were compared after matching for age and gender and controlling for a history of lumbar spine fusion using repeated measures analysis of variance. RESULTS: Data were available for 263 patients treated by 7 surgeons; 149 patients treated with OS and 114 treated with MIS SI joint fusion. Compared to OS patients, MIS patients were on average 10 years older (mean age 57 vs. 46) and 69% of all patients were female. MIS operative measures of EBL, operating time and length of hospitalization were significantly lower than open surgery (p < 0.001). Pain relief, measured as change from baseline to 12 months in VAS pain rating, was 3.5 points lower in the MIS vs. OS group (-6.2 vs. -2.7 points, p < 0.001). When matched for age, gender and a history of prior lumbar spinal fusion, postoperative pain scores were on average 3.0 points (95% CI 2.1 - 4.0) lower in MIS vs. OS (rANOVA p < 0.001). CONCLUSIONS: In this multi-center comparative study, patients who underwent either OS or MIS SI joint fusion showed postoperative improvements in pain score. Compared to OS patients, patients who underwent MIS SI joint fusion had significantly greater pain relief and more favorable perioperative surgical measures.

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

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.