Pelvic fixation has long been the uncomfortable secret of complex spine surgery. Surgeons anchor long deformity constructs into the pelvis using hardware that was never designed for the job — longer, wider pedicle screws driven into iliac and S2-alar-iliac trajectories — and the literature has been telling us for years what happens next: loosening, sacroiliac pain, hardware failure, and reoperation rates in adult deformity surgery that exceed 20% of cases. The base of the construct has been, quite literally, its weakest point.
That is the problem SI-BONE set out to solve with iFuse Bedrock Granite, and it is why the first readout from the PAULA study deserves more attention than the average sponsored abstract. PAULA is a multicenter, real-world evidence study evaluating Granite in one of the most demanding scenarios in spine: adults undergoing multilevel fusion of four or more levels with pelvic fixation. These are long lever arms, poor bone, revision-heavy populations — the environment where pelvic hardware traditionally goes to die.
The preliminary numbers are striking. Across the cohort, the overall pelvic fixation failure rate was 3.3%, four cases in total. Of those, only one — 0.8% — was directly attributable to the Granite implant itself. No intraoperative technical complications related to the device were reported. Set against the historical backdrop of double-digit failure and reoperation figures in this patient population, a sub-1% device-attributable failure rate is the kind of result that changes conversations in the OR corridor.
Some context makes the story more interesting. Granite is not an incremental product. The FDA granted it Breakthrough Device Designation before its 510(k) clearance in 2022, and CMS backed it with a New Technology Add-on Payment — a rare regulatory and reimbursement double that signaled Washington, at least, believed the sacropelvic junction needed a purpose-built answer. The implant’s logic is fusion, not just fixation: a fenestrated, in-growth architecture intended to make the pelvis a biological foundation rather than a mechanical anchor point. PAULA is the test of whether that thesis holds up outside the lab, in real hospitals, with real patients, across prospective and retrospective cohorts followed out to two years.
Now, the honest caveats. This is a sponsor-funded, single-arm, open-label observational study, and the data released so far are preliminary. There is no randomized comparator arm of traditional iliac or S2AI screws sitting next to these numbers; the 20%-plus failure rates we are comparing against come from a heterogeneous body of literature with different definitions, follow-up periods and patient mixes. Real-world evidence is valuable precisely because it reflects practice as it happens, but it also reflects the surgeons and centers willing to participate. A 3.3% failure rate is a headline; the peer-reviewed publication, with full denominators and follow-up, will be the verdict.
Still, the direction of travel matters, and it matters commercially. SI-BONE has spent a decade converting the sacroiliac joint from an afterthought into a franchise, and Granite is its bridgehead into the deformity market — territory dominated by the large spine players. If PAULA’s final data holds anywhere near these levels, the company will be able to walk into every deformity practice with an argument that is very hard to counter: the most failure-prone segment of your construct now has a device designed for it, with real-world numbers behind it. For the incumbents, whose pelvic fixation offerings remain adapted pedicle screws, that is a strategic problem, not a product one.
Preliminary, yes. But the foundation of the construct is shifting — and this time, that is good news.
###
Legal Disclaimer:
Content published on SPINEMarketGroup (thespinemarketgroup.com) is provided for informational purposes only and on an “as is” basis, without warranties of any kind. We do not guarantee the accuracy, completeness, legality, or reliability of any information, images, videos, links, or third-party materials featured on the site. Any views or claims expressed in contributed content or press releases belong to their respective authors or sources. For copyright concerns, factual corrections, or content-related complaints, please contact us directly for review.