Achieving reliable pedicle screw fixation in osteoporotic bone remains one of the most persistent challenges in spine surgery. With a rapidly aging population, more patients now present with compromised bone quality due to advanced osteoporosis, pathological fractures, metastatic lesions, or prior implant failures. In these scenarios, conventional screws often fail to hold—leading to screw loosening, migration, and, ultimately, surgical failure.
For decades, cement-augmented screws have been the go-to solution. Polymethylmethacrylate (PMMA) cement improves immediate fixation strength and helps prevent pull-out in low-density bone. Yet, this solution comes with well-documented risks: cement leakage and significant complications during revision surgeries. Despite its mechanical benefits, PMMA poses serious biological and surgical challenges.
The Real Problem: Stability Without the Risks
One of the primary causes of implant failure is toggling—small micromovements of the pedicle screw within the bone that gradually erode surrounding tissue and compromise fixation. Multiple studies report an average incidence of 22%, with some cases reaching up to 41%¹⁻⁵. Cement has long been the default response to counteract this, but the critical question remains: can we achieve stable fixation without using bone cement?
Many Have Tried—Few Have Succeeded
Over the years, numerous innovations have aimed to replace cement-augmented screws. One notable example was Alphatec Spine’s OsseoScrew, a pedicle screw designed to expand inside the vertebral body to improve fixation in soft bone. While technically interesting, the OsseoScrew never gained clinical traction and was eventually withdrawn from the market. Other concepts followed a similar path—innovative in theory, but falling short in real-world application.This repeated failure has left surgeons skeptical: is a true cement-free solution even possible?
A New Approach: TANTO® and the KUDOS® Modular Platform
A new company, POWEHI Medical, may finally be shifting the narrative. Their modular spine platform, KUDOS®, includes a next-generation pedicle screw called TANTO®, engineered specifically for use in compromised bone—without cement.Unlike standard screws, TANTO® is anatomically shaped to match the inner walls of the pedicle. This design optimizes load transfer across the vertebral body and significantly reduces micromotion. According to in-vitro testing and finite element analysis (FEA) led by Dr. Kiapour at Harvard Medical School, TANTO® offers up to 50% more toggling stability compared to conventional screws—with 0% bone cement.This isn’t just incremental improvement—it represents a potential paradigm shift in how we approach fixation in weak bone.
A Cement-Free Screw With Real-World Benefits
TANTO® delivers a series of clinical and surgical advantages:
- No PMMA – avoiding all risks linked to bone cement
- Superior toggling resistance – even in highly osteoporotic bone
- Bone preservation – eliminating thermal damage and pressure risks
- Shorter surgery time – no cement preparation or injection
- Simplified revision procedures – no hardened cement to remove
- Increased patient safety – reduced risk of embolism or nerve injury
Crucially, TANTO® is not a standalone product. It is part of the KUDOS® system, a modular platform that allows surgeons to adapt their strategy based on real-time intraoperative findings. This modularity gives greater flexibility in the OR, improves workflow, and allows for a personalized approach to spinal fixation—without compromising on safety or stability.
Looking Ahead
As spinal procedures in elderly and fragile patients become more frequent, reliable fixation in poor bone is no longer an exception—it’s the standard demand. TANTO® directly responds to this clinical need with a new class of screw that preserves bone, avoids complications, and still delivers outstanding biomechanical performance.If clinical data confirms what preclinical studies suggest, TANTO® may not be just another alternative to cemented screws—it may well be the solution surgeons have been waiting for.
About POWEHI Medical
POWEHI Medical is a German-based medical technology company dedicated to revolutionizing spinal surgery through cutting-edge, modular implant systems. Recognized among Germany’s most innovative mid-sized companies by STERN in 2023 and recipient of the Best Spine Technology Award at the 2022 NASS Conference in Chicago, POWEHI is setting new standards in spinal fixation.www.powehi-medical.com