USTC First Affiliated Hospital Licenses Self-Fixating Porous Tantalum Acetabular Cup Augment for RMB 22.954 Million

Recently, the First Affiliated Hospital of University of Science and Technology of China released a public notice on the transformation of scientific and technological achievements. The hospital is adopting a combined approach of co-owned intellectual property rights for collaborative implementation and technical cooperative development to facilitate the translation of relevant achievements. It is proposed to“Integrated Fixed Porous Tantalum Metal Acetabular Cup Augment”The series of patents are licensed to CHONGQING RUNZE PHARMACEUTICAL COMPANY LIMITED. The total amount of the licensing agreement is22.954 million yuan, including the contract amount for the collaborative implementation of scientific and technological achievement transformationRMB 954,000and the contract amount for joint technology developmentRMB 22 million. The inventors of this patent are Professor Zhu Chen and his team.

The transferee is CHONGQING RUNZE PHARMACEUTICAL COMPANY LIMITED, a technology-driven enterprise focused on the R&D, production, and clinical translation of biomedical materials and medical devices. By leveraging its independently developed porous tantalum bone graft substitute, which fills the domestic gap in high-end bone repair, the company has become a key force driving the import substitution of domestically produced medical devices.

This invention discloses a self-fixing porous acetabular cup augment. The augment effectively prevents displacement of the main body and significantly reduces micromotion through the tight fit between the limiting lugs and the lug mounting holes, the compressive interlocking of the porous structure of the limiting lugs with the trabecular porous structure of bone tissue, and large-area multi-directional mechanical interlocking, thereby enhancing the implantation accuracy and initial stability of the augment main body. The R&D team utilizes the porous structure to efficiently distribute and transmit stress, eliminate stress shielding, enhance biomechanical stimulation, promote bone ingrowth, achieve regenerative biological integration of the augment main body, and ensure lifelong biological fixation of the augment main body.

In the field of hip revision surgery,Acetabular Bone Defect Repairis a critical step in ensuring surgical success. As a core implantable device, the acetabular cup spacer has long faced challenges in its clinical application“Incompatible materials, imprecise operation, and poor repair stability”the triple challenge, which severely affects patients' postoperative recovery and quality of life. According to clinical statistical data, approximately 35% of hip revision surgeries require the use of augments for assisted repair due to acetabular bone defects. Among these, the loosening rate of traditional augments within 2–3 years postoperativelyUp to 10%-15%,The proportion of patients requiring secondary surgical revision exceeds 8%. This not only increases healthcare costs but also imposes additional suffering on patients.

From the perspective of material properties, existing spacers have a core defect of "biomechanical mismatch."Currently, the titanium alloy or ceramic spacers predominantly used in clinical practice have an elastic modulus as high as 110–130 GPa, whereas the elastic modulus of human cancellous bone is only 0.1–0.5 GPa. This discrepancy, exceeding 200-fold, readily induces the "stress shielding effect." Specifically, the implanted spacer bears the majority of physiological loads, causing surrounding bone tissue to undergo gradual resorption due to insufficient mechanical stimulation, which subsequently leads to spacer loosening and prosthetic displacement.

More critically, traditional spacers typically feature a dense structure that precludes bone tissue ingrowth, relying solely on mechanical fixation. With long-term use, micromotion at the bone-implant interface commonly exceeds 0.5 mm, which can easily lead to fixation failure and serves as a primary cause of postoperative prosthetic loosening.

At the level of intraoperative manipulation, traditional spacers face the challenges of "poor positioning accuracy and high risk of secondary injury."Due to the lack of dedicated clamping and positioning tools, surgeons are forced to use general-purpose instruments to grasp the augmentation blocks. This often leads to slippage and displacement during manipulation, resulting in placement accuracy deviations frequently exceeding 1 mm, with severe cases reaching over 1 cm. To adjust the block position, surgeons must repeatedly lever it, which not only prolongs surgical time (by an average of 20 to 30 minutes) but may also cause secondary damage to the acetabular bone tissue, further compromising the support capacity of the bone defect area. Furthermore, the conformity between traditional augmentation blocks and the acetabular defect relies on the surgeon’s empirical judgment, making precise matching difficult. This can lead to gaps that affect the stability of subsequent acetabular cup implantation and even cause interference with screw installation, forcing intraoperative interruptions for adjustments.

Starting from the individualized needs of patients, existing technologies still have obvious limitations in terms of "adaptability."Acetabular bone defects vary significantly among patients in both size and morphology, including segmental and cavitary defects. Traditional augments, however, are available in only 3–5 fixed sizes, making it difficult to precisely match complex defect patterns. For instance, in patients with extensive defects of the superior acetabular wall, conventional augments often fail to provide adequate support, frequently necessitating the stacking of multiple augments. This not only increases procedural complexity but may also lead to localized stress concentration due to uneven load distribution between the augments, thereby accelerating prosthetic failure. Furthermore, traditional augments lack self-fixation design; after implantation, they rely on indirect fixation via acetabular cup screws. If screw placement conflicts with the augment, surgical options are further constrained, compromising repair outcomes.

More importantly,Existing technologies struggle to simultaneously meet the clinical demands for “initial stability and long-term integration.”Some spacers enhance initial fixation by increasing surface roughness, yet they still fail to effectively address the issue of stress shielding. Although a few porous-structured spacers can promote bone ingrowth, their lack of positioning features results in insufficient implantation accuracy and a persistent risk of postoperative displacement. This situation, characterized by “single-function optimization and imbalanced overall performance,” forces clinicians to face a dilemma between “prioritizing accuracy” and “prioritizing stability” when selecting spacers, making it difficult to meet the core requirements of hip revision surgery for “precise reconstruction and long-term stability.”

In clinical practice, acetabular cup augments exist“Incompatible materials, imprecise operation, and poor repair stability”significant pain points, this issue prompted Zhu Chen’s team from the First Affiliated Hospital of USTC to collaborate with Chongqing Runze Pharmaceutical Company Limited on technological innovation. The core advantage of the successfully commercialized patented technology, the “Self-Fixing Porous Tantalum Metal Acetabular Cup Augment,” lies in"Porosity Tantalum Biomimetic Material" and "Integrated Self-Fixation Structure", a comprehensive solution has been developed. This technology has achieved breakthroughs across all dimensions—from biocompatibility and intraoperative procedural precision to long-term restorative stability—thereby completely overcoming the limitations of traditional spacers that rely on mechanical fixation and suffer from insufficient accuracy.

This technology has first achieved a disruptive breakthrough in material innovation—Successfully overcame the drawback of “biomechanical mismatch” inherent in traditional titanium alloy and ceramic spacers, and pioneered the “porous tantalum biomimetic trabecular structure.”The elastic modulus of traditional spacers (110–130 GPa) differs significantly from that of human cancellous bone (0.1–0.5 GPa), which readily leads to stress shielding. In contrast, the porous tantalum spacer developed in this patent achieves a high match with the elastic modulus of human cancellous bone by precisely controlling porosity (50%–90%, preferably 70%–80%) and microstructure (strand diameter: 100–800 μm; pore size: 200–800 μm), thereby completely eliminating the stress shielding effect.

More importantly,The interconnected pores of the porous structure can effectively promote bone tissue ingrowth, achieving biological integration.Testing has demonstrated that the bone ingrowth rate exceeds 60% at three months post-implantation, and the loosening rate at 2–3 years post-operatively can be reduced from the traditional 10%–15% to below 3%, thereby addressing the clinical challenge of “prone to early fixation failure and difficult to achieve long-term fusion.”

In terms of self-fixation functional design, the spacer is achieved through“Limiting Support Ears + Precise Positioning”innovative solution that achieves zero intraoperative displacement and long-term high stability, effectively addressing the challenges of “poor operational precision and high risk of secondary injury.”First, it innovatively designed a triangular pyramid-shaped limit lug:Three retaining lugs are evenly distributed along the periphery of the convex curved surface of the spacer body. The bottom edge length, side ridge length, and concave curvature radius are all 3–10 mm (preferably 5–7 mm). During implantation, these lugs form a slight interference fit with pre-drilled lug installation holes in the acetabular fossa. Combined with the compression and interlocking of the porous structure with trabecular bone, this achieves multi-directional mechanical interlock. Compared to the limitations of traditional spacers, which lack positioning structures and exhibit displacement exceeding 1 mm, this design controls spacer displacement to within 0.2 mm, reducing micromotion at the bone interface from over 0.5 mm to under 0.2 mm, thereby significantly enhancing initial stability.

Second, the supporting development of a three-point adaptive clamping tool:By integrating positioning scale markings, this tool enables precise grasping of spacers and achieves millimeter-level positioning, effectively preventing the slippage associated with traditional general-purpose instruments. Clinical simulation studies demonstrate that using this tool reduces spacer placement time from 20 minutes to 5 minutes, eliminating the need for repeated adjustments and thereby lowering the risk of secondary injury to acetabular bone tissue. Furthermore, the spacer body features through-holes of 4–9 mm (preferably 7 mm) designed to avoid interference with acetabular cup installation screws, resolving the issue of screw-spacer conflict encountered with conventional spacers. This design ensures compatibility with the majority of acetabular cup models available on the market, significantly enhancing its universality.

Furthermore, this technology has achieved a dual breakthrough in “structural optimization and industrialization adaptation.”In terms of structural optimization,The limit support ears and the main body of the pad are integrally formed, eliminating assembly interfaces and enabling more uniform stress transmission; the central axis of the support ears forms an angle of 10–60° with the central axis of the pad body, effectively increasing the load-bearing area and preventing localized stress concentration on the hip bone.In terms of industrialization,The spacer is made of medical-grade tantalum or titanium alloy, offering excellent biocompatibility while ensuring manufacturability. Utilizing powder metallurgy technology, the spacer can be mass-produced and customized in various sizes to match the dimensions and morphology of acetabular defects. This allows it to accommodate different types of defects, such as segmental and cavitary deficiencies, thereby meeting the requirements for personalized reconstruction.

In the sector of porous tantalum implants for hip revision surgery, domestic and international companies have formed“International Giants Dominate the High-End Market, While Domestic Enterprises Accelerate Innovation to Break Through”competitive landscape, various porous tantalum repair products continue to iterate in material optimization, structural design, and clinical adaptability, jointly driving technological upgrades in this field.

Zimmer Biomet(Zimmer Biomet), as a pioneer in porous tantalum bone repair materials, has long held a dominant position in the global high-end market. Its core products“Trabecular Metal™”Acetabular Augment Series, refined using tantalum metal powder metallurgy technology, with a porosity as high as 75%-85%.

With its biomimetic structure highly similar to human bone tissue, this product achieves excellent osseointegration and is widely recognized in clinical practice as the “gold standard.” The series has evolved to its third generation, optimizing the curvature of the spacer surface and the design of screw holes to accommodate a wider range of acetabular bone defects.

Currently, this product has been widely used in clinical practice worldwide, with over one million cumulative implantations, and the 5-year postoperative loosening rate is controlled within 5%. However, the product still lacks a dedicated self-fixing structure, requiring precise positioning during surgery based on the surgeon's experience. Additionally, its high price (over 30,000 yuan per spacer) limits its adoption in primary healthcare institutions.

Guided by the objectives of “filling technological gaps and meeting clinical needs,” domestic enterprises are accelerating breakthroughs in the field of porous tantalum repair devices, forging distinct development pathways.

Aikang Medical3D-Printed Personalized Acetabular Augments, launched in the field of personalized orthopedic implants, are representative products of domestic 3D printing technology in hip revision arthroplasty. Based on precise modeling from patient CT imaging data, these devices are fabricated using metal 3D printing technologies (such as Electron Beam Melting, EBM). They can be customized to match various types of acetabular bone defects, including segmental and cavitary defects, achieving a "puzzle-like" snug fit with the bone defect area and reconstructing the hip joint's center of rotation.

Some high-end models feature a gradient porous structure design, combined with plasma-sprayed microporous surface treatment technology, achieving a porosity of 50%-70%. This design reduces the elastic modulus to minimize stress shielding while promoting bone tissue ingrowth. Paired with a highly cross-linked polyethylene liner, it enhances the wear resistance of the prosthesis and supports large-diameter femoral head configurations of 32 mm and 36 mm, accommodating the activity needs of different patients.

This self-fixating porous tantalum metal acetabular augments technique effectively addresses core challenges in acetabular defect reconstruction—namely, biomechanical mismatch of materials, low intraoperative precision, and poor long-term stability—by integrating biomimetic porous tantalum with an integrated self-fixating structure, potentially offering an innovative solution that ensures both restorative efficacy and surgical safety.