Modified porous tantalum rod technique for the treatment of femoral head osteonecrosis

Network meta-analysis of invasive treatment for early-stage osteonecrosis of the femoral head

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is a common disabling disease in orthopedics. Blocking the progression of ONFH in the early stage is essential for avoiding total hip replacement.

PURPOSES

The purpose of this study is to evaluate the effect of invasive treatment on early-stage ONFH.

METHODS

According to the PRISMA guidelines, relevant English databases were searched in August 2022 to collect published research. Extract result indicators and conduct network meta-analysis using R software.

RESULTS

A total of 15 RCTs were included. All patients were diagnosed with early-stage ONFH. The surface under the cumulative ranking curve (SUCRA) showed that CD + BMMSC and CD + PRP were the most effective in improving HHS. The results of the league table showed that CD + BMMSC was superior to CD alone. Meanwhile, the SUCRA for FR showed that CD + BG + BMMSC was the most likely to be the most effective in reducing FR. The league table revealed that CD + BG, CD + BG + BMMSC, and CD + BMMSC were superior to CD alone, with statistically significant differences.

CONCLUSION

Considering the HHS and FR, CD + BMMSC may be the optimal treatment option to effectively delay the progression of ONFH and restore the postoperative function of patients.

REGISTRATION NUMBER

The study protocol has been registered on the PROSPERO platform (CRD42023380169).

Icariin-loaded 3D-printed porous Ti6Al4V reconstruction rods for the treatment of necrotic femoral heads

Avascular necrosis of the femoral head is a prevalent hip joint disease. Due to the damage and destruction of the blood supply of the femoral head, the ischemic necrosis of bone cells and bone marrow leads to the structural changes and the collapse of the femoral head. In this study, an icariin-loaded 3D-printed porous Ti6Al4V reconstruction rod (referred to as reconstruction rod) was prepared by 3D printing technology. The mechanical validity of the reconstruction rod was verified by finite element analysis. Through infilling of mercapto hyaluronic acid hydrogel containing icariin into the porous structure, the loading of icariin was achieved. The biological efficacy of the reconstruction rod was confirmed through in vitro cell experiments, which demonstrated its ability to enhance MC3T3-E1 cell proliferation and facilitate cellular adhesion and spreading. The therapeutic efficacy of the reconstruction rod was validated in vivo through a femoral head necrosis model using animal experiments. The results demonstrated that the reconstruction rod facilitated osteogenesis and neovascularization, leading to effective osseointegration between bone and implant. This study provides innovative strategy for the treatment of early avascular necrosis of the femoral head. STATEMENT OF SIGNIFICANCE: The bioactivity of medical titanium alloy implants plays an important role in bone tissue engineering. This study proposed a medicine and device integrated designed porous Ti6Al4V reconstruction rod for avascular necrosis of the femoral head, whose macroscopic structure was customized by selective laser melting. The bionic porous structure of the reconstruction rod promoted the growth of bone tissue and formed an effective interface integration. Meanwhile, the loaded icariin promoted new bone and vascular regeneration, and increased the bone mass and bone density. Therefore, the implantation of reconstruction rod interfered with the further development of necrosis and provided a positive therapeutic effect. This study provides innovative strategies for the treatment of early avascular necrosis of femoral head.

Preparation, modification, and clinical application of porous tantalum scaffolds

Porous tantalum (Ta) implants have been developed and clinically applied as high-quality implant biomaterials in the orthopedics field because of their excellent corrosion resistance, biocompatibility, osteointegration, and bone conductivity. Porous Ta allows fine bone ingrowth and new bone formation through the inner space because of its high porosity and interconnected pore structure. It contributes to rapid bone integration and long-term stability of osseointegrated implants. Porous Ta has excellent wetting properties and high surface energy, which facilitate the adhesion, proliferation, and mineralization of osteoblasts. Moreover, porous Ta is superior to classical metallic materials in avoiding the stress shielding effect, minimizing the loss of marginal bone, and improving primary stability because of its low elastic modulus and high friction coefficient. Accordingly, the excellent biological and mechanical properties of porous Ta are primarily responsible for its rising clinical translation trend. Over the past 2 decades, advanced fabrication strategies such as emerging manufacturing technologies, surface modification techniques, and patient-oriented designs have remarkably influenced the microstructural characteristic, bioactive performance, and clinical indications of porous Ta scaffolds. The present review offers an overview of the fabrication methods, modification techniques, and orthopedic applications of porous Ta implants.

Prognostic factors in the management of osteonecrosis of the femoral head: A systematic review

BACKGROUND

Several hip preserving techniques have been described for the management of osteonecrosis of the femoral head (ONFH). This systematic review identified prognostic factors in the treatment of ONFH that are associated with treatment failure and conversion to total hip arthroplasty (THA).

MATERIAL AND METHODS

This study followed the PRISMA guidelines. The literature search was conducted in November 2021. All clinical trials comparing two or more treatments for femoral head osteonecrosis were accessed. A multivariate analysis was performed to investigate the association between baseline characteristics and the surgical outcome. A multiple linear model regression analysis through the Pearson Product-Moment Correlation Coefficient (r) was used.

RESULTS

Data from 88 articles (6112 procedures) were retrieved. Female gender was associated with increased time to THA (P = 0.03) and reduced rate of THA (P = 0.03). Longer symptom duration before treatment was associated with shorter time to failure (P = 0.03). Increased pre-treatment VAS was associated with reduced time to failure (P = 0.03) and time to THA (P = 0.04). Reduced pre-treatment hip function was associated with increased rate of THA (P = 0.02) and failure (P = 0.005). Patient age and BMI, aetiology, time from surgery to full weight bearing and the side did not show evidence of a statistically significant association with the surgical outcome.

CONCLUSION

Male gender, longer symptom duration before treatment, higher VAS scores, and lower HHS scores were negative prognostic factors after treatment for osteonecrosis of the femoral head.

Core Decompression and Bone Marrow Aspiration Concentrate Grafting for Osteonecrosis of the Femoral Head

BACKGROUND

Core decompression (CD) with bone marrow aspiration concentrate (BMAC) is a technique that may improve outcomes in osteonecrosis of the femoral head (ONFH). The primary aim of this study was to evaluate the radiographic progression free survival (PFS) of CD augmented with BMAC. Secondary aims were to determine the survivorship with conversion (CFS) to total hip arthroplasty (THA) as an endpoint, determine prognostic factors, and characterize the cellular quality of the BMAC.

METHODS

A retrospective cohort study of 61 femoral heads (40 patients) was performed. Patient demographics, comorbidities, BMI, smoking status, etiology, location and extent of ONFH were recorded. The primary endpoint was radiographic progression of ONFH and secondarily, conversion to THA. Additional aims were to determine predictive factors for progression and report the cellular characteristics of the BMAC. Data obtained were compared to the results of a prior randomized controlled trial comparing CD alone versus CD with polymethylmethacrylate cement (PMMA) augmentation.

RESULTS

Radiographic PFS of CD with BMAC at 2 and 5 years was 78.3% and 53.3%, respectively. The risk of progression was lower in the CD with BMAC group compared to CD alone (HR0.45, p = 0.03), however this difference no longer remained statistically significant on multivariate analysis. Conversion to total hip arthroplasty free survival (CFS) of CD with BMAC at both 2 and 5 years was 72.1% and 54.6%, respectively with no differences compared to the control groups (CD alone, CD and PMMA). The predictive factors for progression were obesity (BMI ≥ 30) and the extent of the disease as quantified by either percentage involvement, necrotic index or modified necrotic index.

CONCLUSIONS

No differences in PFS or CFS between CD with BMAC compared to CD alone or CD with PMMA were identified. Independent statistically significant predictors of progression-free survival or conversion to THA are BMI ≥ 30 and the extent of ONFH. Further research with an adequately powered randomized controlled trial is needed.

LEVEL OF EVIDENCE

3.

Tissue Engineering Strategies for Treating Avascular Necrosis of the Femoral Head

Avascular necrosis (AVN) of the femoral head commonly leads to symptomatic osteoarthritis of the hip. In older patients, hip replacement is a viable option that restores the hip biomechanics and improves pain but in pediatric, adolescent, and young adult patients hip replacements impose significant activity limitations and the need for multiple revision surgeries with increasing risk of complication. Early detection of AVN requires a high level of suspicion as diagnostic techniques such as X-rays are not sensitive in the early stages of the disease. There are multiple etiologies that can lead to this disease. In the pediatric and adolescent population, trauma is a commonly recognized cause of AVN. The understanding of the pathophysiology of the disease is limited, adding to the challenge of devising a clinically effective treatment strategy. Surgical techniques to prevent progression of the disease and avoid total hip replacement include core decompression, vascular grafts, and use of bone-marrow derived stem cells with or without adjuncts, such as bisphosphonates and bone morphogenetic protein (BMP), all of which are partially effective only in the very early stages of the disease. Further, these strategies often only improve pain and range of motion in the short-term in some patients and do not predictably prevent progression of the disease. Tissue engineering strategies with the combined use of biomaterials, stem cells and growth factors offer a potential strategy to avoid metallic implants and surgery. Structural, bioactive biomaterial platforms could help in stabilizing the femoral head while inducing osteogenic differentiation to regenerate bone and provide angiogenic cues to concomitantly recover vasculature in the femoral head. Moreover, injectable systems that can be delivered using a minimal invasive procedure and provide mechanical support the collapsing femoral head could potentially alleviate the need for surgical interventions in the future. The present review describes the limitations of existing surgical methods and the recent advances in tissue engineering that are leading in the direction of a clinically effective, translational solution for AVN in future.

The Clinical Application of Porous Tantalum and Its New Development for Bone Tissue Engineering

Porous tantalum (Ta) is a promising biomaterial and has been applied in orthopedics and dentistry for nearly two decades. The high porosity and interconnected pore structure of porous Ta promise fine bone ingrowth and new bone formation within the inner space, which further guarantee rapid osteointegration and bone-implant stability in the long term. Porous Ta has high wettability and surface energy that can facilitate adherence, proliferation and mineralization of osteoblasts. Meanwhile, the low elastic modulus and high friction coefficient of porous Ta allow it to effectively avoid the stress shield effect, minimize marginal bone loss and ensure primary stability. Accordingly, the satisfactory clinical application of porous Ta-based implants or prostheses is mainly derived from its excellent biological and mechanical properties. With the advent of additive manufacturing, personalized porous Ta-based implants or prostheses have shown their clinical value in the treatment of individual patients who need specially designed implants or prosthesis. In addition, many modification methods have been introduced to enhance the bioactivity and antibacterial property of porous Ta with promising in vitro and in vivo research results. In any case, choosing suitable patients is of great importance to guarantee surgical success after porous Ta insertion.

Repair of non-traumatic femoral head necrosis by marrow core decompression with bone grafting and porous tantalum rod implantation

Objective

To compare the clinical effects of marrow core decompression with bone grafting and marrow core decompression with porous tantalum rod implantation in treating avascular necrosis of non-traumatic femoral head.

Methods

This prospective study selected 60 patients (74 hips) with avascular necrosis of femoral head admitted to Daping Hospital from January 2018 to March 2019. According to treatment methods, the 60 patients were randomly divided into two groups, i.e. 30 patients in one group were treated by marrow core decompression with bone grafting, and the other 30 patients in the other group were treated with marrow core decompression and porous tantalum rod implantation.

Results

All implantation treatments were successful. No significant difference was found in surgical duration, hemorrhage volume and duration of hospitalization stay between the two groups during follow-up. All Harris scores were significantly improved (P<0.05) following treatment compared to those before treatment. The Harris score of patients treated with porous tantalum rod implantation was higher than that of patients treated with bone grafting (P<0.05) after 12 months following treatment and such a difference was significant.

Conclusion

The combination of marrow core decompression and porous tantalum rod implantation can better improve the functions of hip joints with early femoral head necrosis than marrow core decompression with bone grafting, and can also prevent articular cartilage from collapsing gradually.

Outcome of tantalum rod insertion in the treatment of osteonecrosis of the femoral head with minimum follow-up of 1 year: a meta-analysis and systematic review

Osteonecrosis of the femoral head (ONFH) is a debilitating disease that can cause deformity and collapse of the femoral head, thus leading to the development of degenerative joint disease that can incapacitate the patient with pain and reduction in hip mobility. This study aims to determine the safety and efficacy of tantalum rod insertion in the treatment of ONFH with a minimum follow-up period of 1 year. A multi-database search was performed according to Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. Data from studies assessing the clinical and radiological outcomes as well as complications of tantalum rod insertion in the treatment of ONFH with a minimum follow-up period of 1 year were extracted and analyzed. Ten studies were included in this meta-analysis, consisting of 550 hips. There was a statistically significant increase in HHS (MD = 30.35, 95% CI: 20.60-40.10, P < 0.001) at final follow-up versus pre-operative scores. The weighted pooled proportion (PP) of radiographic progression of ONFH was 0.221 (95% CI: 0.148-0.316), while that of progression into femoral head collapse was 0.102 (95% CI: 0.062-0.162). Conversion to total hip arthroplasty (THA) had a PP of 0.158 (95% CI: 0.107-0.227) with a mean weighted period of 32.4 months (95% CI: 24.9-39.9 months). Subgroup analysis of conversion to THA when tantalum rods were used in conjunction with bone grafting (PP = 0.150, 95% CI: 0.092-0.235) showed a marginal risk reduction than when compared with subgroup analysis of tantalum rods being used alone (PP = 0.154, 95% CI: 0.078-0.282). Tantalum rod is a safe alternative option to the current joint-preserving procedures available in the treatment of ONFH. However, more studies are needed to investigate and identify the most appropriate patients who would benefit most and the synergistic effect brought on by the use of complementary biological augmentation of bone grafting or stem cells with tantalum rods.

A 3D printed porous titanium alloy rod with biogenic lamellar configuration for treatment of the early-stage femoral head osteonecrosis in sheep

There is no ideal implant for mechanical strut on early-stage osteonecrosis of the femoral head (ONFH) after core decompression. In this study, a biogenic trabecular porous titanium rod with lamellar configuration was designed and fabricated using selective laser melting technique. Early-stage ONFH of sheep induced by cryo-insult were dealt with core decompression combined with rod insertion (Rod group) and core decompression alone (CD group) after X-ray evaluation was used to assess the necrotic region one months after cryo-intervention. Bone integration and ingrowth of the two groups were investigated and compared. Early-stage ONFH intervened with the rod gained better bone ingrowth than CD 3 and 6 months after the intervention, as evidenced by radiographic, micro-CT and histological evaluation. X-ray images showed compact integration between rods and peripheral bone, evidenced by no radiolucent lines encircling the rods at 3 and 6 months. Micro-CT and histological images showed that the new bone had grown into the centre of rods along the metal at 3 months, whereas the new bone grew mainly at the periphery of the decompressive channel. Micro-CT analysis show that the ratios of bone volume to total volume (BV/TV) of volume of interest (VOI) in Rod group was 890.0% and 438.1% higher than CD group at 3 (0.198 ± 0.0094 VS 0.020 ± 0.0058, p < 0.05, n = 3) and 6 (0.226 ± 0.0166 VS 0.042 ± 0.0061, p < 0.05, n = 3) months respectively. Histological analysis showed that the BV/TV of VOI in Rod group was 881.0% and 413.3% higher than CD group at 3 (0.206 ± 0.0102 VS 0.021 ± 0.0061, p < 0.05, n = 3) and 6 (0.231 ± 0.0156 VS 0.045 ± 0.0059, p < 0.05, n = 3) months respectively. The mechanical tests revealed that the maximum load of Rod group was 57.6% larger than CD group at 6 months (4505.25 ± 443.86 N VS 2858.25 ± 512.91 N, p < 0.05, n = 3). These favourable short-term results can provide insight on treatment of early-stage ONFH.

AAV-Anti-miR-214 Prevents Collapse of the Femoral Head in Osteonecrosis by Regulating Osteoblast and Osteoclast Activities

Osteonecrosis of the femoral head, an intractable but common disease that eventually triggers collapse of the femoral head, is characterized by increased osteoclast activity and markedly decreased osteoblast activity in the necrotic region of the femoral head. MicroRNA (miRNA)-214 (miR-214) may play important roles in vertebrate skeletal development by inhibiting osteoblast function by targeting activating transcription factor 4 (ATF4) and promoting osteoclast function via phosphatase and tensin homolog (PTEN). This study revealed significantly increased levels of miR-214 in necrotic regions, with commensurate changes in the numbers of its target cells (both osteoblasts and osteoclasts). To investigate whether targeting miR-214 could prevent femoral head collapse, we constructed an adeno-associated virus (AAV)-associated anti-miR-214 (AAV-anti-miR-214) and evaluated its function in vivo. AAV-anti-miR-214 promoted osteoblast activity and diminished osteoclast activity, effectively preventing collapse of the femoral head in a rat model of osteonecrosis.

Porous Tantalum and Titanium in Orthopedics: A Review

Porous metal is metal with special porous structures, which can offer high biocompatibility and low Young's modulus to satisfy the need for orthopedic applications. Titanium and tantalum are the most widely used porous metals in orthopedics due to their excellent biomechanical properties and biocompatibility. Porous titanium and tantalum have been studied and applied for a long history until now. Here in this review, various manufacturing methods of titanium and tantalum porous metals are introduced. Application of these porous metals in different parts of the body are summarized, and strengths and weaknesses of these porous metal implants in clinical practice are discussed frankly for future improvement from the viewpoint of orthopedic surgeons. Then according to the requirements from clinics, progress in research for clinical use is illustrated in four aspects. Various creative designs of microporous and functionally gradient structure, surface modification, and functional compound systems of porous metal are exhibited as reference for future research. Finally, the directions of orthopedic porous metal development were proposed from the clinical view based on the rapid progress of additive manufacturing. Controllable design of both macroscopic anatomical bionic shape and microscopic functional bionic gradient porous metal, which could meet the rigorous mechanical demand of bone reconstruction, should be developed as the focus. The modification of a porous metal surface and construction of a functional porous metal compound system, empowering stronger cell proliferation and antimicrobial and antineoplastic property to the porous metal implant, also should be taken into consideration.

Outcome after a new porous tantalum rod implantation for treatment of early-stage femoral head osteonecrosis

Background

Tantalum rods have been used in osteonecrosis of the femoral head (ONFH) for several years, while Zimmer trabecular metal implants have been proposed as the best choice. The aim of this study was to evaluate the effect of a new porous tantalum rod on the treatment of early ONFH.

Methods

From July 2014 to December 2015, 19 patients (21 hips) were treated with Runze tantalum rod, and 20 patients (20 hips) received Zimmer tantalum prosthesis. All patients were followed up for at least 3 years.

Results

There was no significant difference in demographic characteristics and the Harris Hip Score (HHS) improvement between the two groups. Kaplan-Meier analysis did not show any statistically significant difference in survival rates. One case in the Runze group had persistent pain and required conversion to total hip arthroplasty (THA) 8 months post-surgery. Histological evaluations revealed the presence of abundant new bone ingrowth into pores of the tantalum. The osteonecrosis observed in other patients was almost unchanged. At final follow-up, progressive collapse of the femoral head or the apparent joint space narrowing had not occurred.

Conclusions

Compared with the traditional implants, implantation of the Chinese tantalum rod in the treatment of Association Research Circulation Osseous (ARCO) stages I, and II ONFH demonstrated highly encouraging clinical results.

Osteonecrosis of the femoral head: pathophysiology and current concepts of treatment

Osteonecrosis of the femoral head is a disabling pathology affecting a young population (average age at treatment, 33 to 38 years) and is the most important cause of total hip arthroplasty in this population. It reflects the endpoint of various disease processes that result in a decrease of the femoral head blood flow.The physiopathology reflects an alteration of the vascularization of the fine blood vessels irrigating the anterior and superior part of the femoral head. This zone of necrosis is the source of the loss of joint congruence that leads to premature wear of the hip.Several different types of medication have been developed to reverse the process of ischemia and/or restore the vascularization of the femoral head. There is no consensus yet on a particular treatment.The surgical treatments aim to preserve the joint as far as the diagnosis could be made before the appearance of a zone of necrosis and the loss of joint congruence. They consist of bone marrow decompressions, osteotomies around the hip, vascular or non-vascular grafts.Future therapies include the use of biologically active molecules as well as implants impregnated with biologically active tissue. Cite this article: EFORT Open Rev 2019;4:85-97. DOI: 10.1302/2058-5241.4.180036.

A 3D Printed Porous Titanium Alloy Rod with Diamond Crystal Lattice for Treatment of the Early-Stage Femoral Head Osteonecrosis in Sheep

Instruments made of porous titanium alloy and fabricated with a 3D printed technique are increasingly used in experimental and clinical research. To date, however, few studies have assessed their use in early-stage osteonecrosis of the femoral head (ONFH). In this study, porous titanium alloy rods (Ti-Rod) with diamond crystal lattice, fabricated using an electron beam melting (EBM) technique, were implanted into sheep models (n=9) of early-stage ONFH for 6 months. Bone ingrowth and integration were investigated and compared with those of sheep (n=9) undergoing core decompression (CD) alone. Following Ti-Rod implantation, femoral heads showed fine osteointegration, with X-ray evaluation showing compact integration between peripheral bone and rods without radiolucent lines encircling the rods, as well as new bone growth along the metal trabeculae without the intervention of fibrous tissue. The regions of interest (ROIs) of femoral heads showed fine bone ingrowth after Ti-Rod implantation than CD alone. By micro-CT evaluation, the ratios of bone volume to total volume (BV/TV) of ROIs in Rod group was 930 % and 452 % higher than CD group after 3 (0.206 ± 0.0095 vs. 0.020 ± 0.0058, p < 0.05, n=3) and 6 (0.232 ± 0.0161 vs. 0.042 ± 0.0061, p < 0.05, n=3) months respectively. By histological evaluation, the BV/TV of ROIs in Rod group was 647 % and 422 % higher than CD group after 3 (0.157 ± 0.0061 vs. 0.021 ± 0.0061, p < 0.05, n=3) and 6 (0.235 ± 0.0145 vs. 0.045 ± 0.0059, p < 0.05, n=3) months respectively. The new bone grew along metal trabeculae into the center of the rod with a rapid bone ingrowth in Rod gorup. Whereas in CD group, new bone grew mainly at the periphery of the decompressive channel with a slow bone ingrowth. Mechanical analysis showed that maximum load on the femoral head-necks was 31 % greater 6 months after Ti-Rod implantation than after CD alone when the vertical press reached the apex (3751.75 ± 391.96 vs. 2858.25 ± 512.91 N, p < 0.05, n=3). The association of rod implantation with fine bone ingrowth, osteointegration, and favorable mechanical properties suggests that implantation of the porous titanium alloy rod with the diamond crystal lattice may be a beneficial intervention for patients with early-stage ONFH.

Corticosteroid-induced Osteonecrosis of the Femoral Head: Detection, Diagnosis, and Treatment in Earlier Stages

Objective:

This review aimed to provide a current recommendation to multidisciplinary physicians for early detection, diagnosis, and treatment of corticosteroid-induced osteonecrosis of the femoral head (ONFH) based on a comprehensive analysis of the clinical literature.

Data Sources:

For the purpose of collecting potentially eligible articles, we searched for articles in the PubMed, Cochrane Library, Embase, and CNKI databases up to February 2017, using the following key words: “corticosteroid”, “osteonecrosis of the femoral head”, “risk factors”, “diagnosis”, “prognosis”, and “treatment”.

Study Selection:

Articles on relationships between corticosteroid and ONFH were selected for this review. Articles on the diagnosis, prognosis, and intervention of earlier-stage ONFH were also reviewed.

Results:

The incidence of corticosteroid-induced ONFH was associated with high doses of corticosteroids, and underlying diseases in certain predisposed individuals mainly occurred in the first 3 months of corticosteroid prescription. The enhanced awareness and minimized exposure to the established risk factors and earlier definitive diagnosis are essential for the success of joint preservation. When following up patients with ONFH, treatment should be started if necessary. Surgical treatment yielded better results than conservative therapy in earlier-stage ONFH. The ideal purpose of earlier intervention and treatment is permanent preservation of the femoral head without physical restrictions in daily living.

Conclusions:

Clinicians should enhance their precaution awareness of corticosteroid-induced ONFH. For high-risk patients, regular follow-up is very important in the 1^st year after high-dose prescription of corticosteroids. Patients with suspected ONFH should be referred to orthopedists for diagnosis and treatment in its earlier stage to preserve the joint.

Enhanced repair of segmental bone defects in rabbit radius by porous tantalum scaffolds modified with the RGD peptide

Fast and stable repair of segmental bone defects remains a challenge for clinical orthopedic surgery. In recent years, porous tantalum has been widely applied in clinical orthopedics for low modulus of elasticity, with three-dimensional microstructures similar to cancellous bone and excellent biocompatibility. To further improve bone the repairing ability of porous tantalum, the cyclo(-RGDfK-) peptide was coated on the surface of porous tantalum scaffolds. A model of 15 mm segmental defect was made at the midshaft of right radius in New Zealand White rabbits. In the experimental group, defects were implanted (press-fit) using porous tantalum scaffolds modified with cyclo(-RGDfK-) peptide. Control animals were implanted with non-modified porous tantalum scaffolds or xenogeneic cancellous bone scaffolds, respectively. No implant was provided for the blank group. Bone repair was assessed by X-ray and histological observations at 4, 8, and 16 weeks post-operation, with biomechanical tests and micro-computed tomography performed at 16 weeks post-surgery. The results showed that bone formation was increased at the interface and inside the inner pores of modified porous tantalum scaffolds than those of non-modified porous tantalum scaffolds; biomechanical properties in the modified porous tantalum group were superior to those of the non-modified porous tantalum and xenogeneic cancellous bone groups, while new bone volume fractions using micro-computed tomography analysis were similar between the modified porous tantalum and xenogeneic cancellous bone groups. Our findings suggested that modified porous tantalum scaffolds had enhanced repairing ability in segmental bone defect in rabbit radius, and may serve as a potential material for repairing large bone defects.