Tantalum Rod Implantation Research Articles

Partial femoral head replacement: a new innovative hip-preserving approach for treating osteonecrosis of the femoral head and its finite element analysis.

Purpose: Controversy remains regarding the optimal treatment for stage III Osteonecrosis of the femoral head (ONFH). This study presents, for the first time, the precise treatment of stage III ONFH using the "substitute the beam for a pillar" technique and performs a comparative finite element analysis with other hip-preserving procedures. Methods: A formalin-preserved femur of male cadavers was selected to obtain the CT scan data of femur. The proximal femur model was reconstructed and assembled using Mimics 20.0, Geomagic, and UG-NX 12.0 software with four different implant types: simple core decompression, fibula implantation, porous tantalum rod implantation, and partial replacement prosthesis. The finite element simulations were conducted to simulate the normal walking gait, and the stress distribution and displacement data of the femur and the implant model were obtained. Results: The peak von Mises stress of the femoral head and proximal femur in the partial replacement of the femoral head (PRFH) group were 22.8MPa and 37.4MPa, respectively, which were 3.1%-38.6% and 12.8%-37.4% lower than those of the other three surgical methods. Conclusion: The PRFH group exhibits better mechanical performance, reducing stress and displacement in the ONFH area, thus maintaining femoral head stability. Among the four hip-preserving approaches, from a biomechanical perspective, PRFH offers a new option for treating ONFH.

The effects of nano-hydroxyapatite/polyamide 66 scaffold on dog femoral head osteonecrosis model: a preclinical study

The lack of mechanical support in the bone tunnel formed after CD often results in a poor therapeutic effect in ONFH. The n-HA/P66 has excellent biocompatibility and mechanical properties and has been widely used in bone regeneration. The present study aimed to evaluate the effects of n-HA/P66 scaffold treatment in a dog model of ONFH. A FEA was performed to analyze the mechanical changes in the femoral head after CD and n-HA/P66 scaffold or tantalum rod implantation. Fifteen male beagles were selected to establish the model of ONFH by liquid nitrogen freezing method, and the models were identified by x-ray and MRI 4 weeks after modeling and randomly divided into three groups. Nine weeks later, femoral head samples were taken for morphology, micro-CT, and histological examination. The FEA showed that the n-HA/P66 scaffold proved the structural support in the bone tunnel, similar to the tantalum rod. The morphology showed that the femoral head with n-HA/P66 implantation is intact, while the femoral heads in the model group and CD group are collapsing. Moreover, the micro-CT results of the n-HA/P66 scaffold group were better than the model group and the CD group, and the interface between the n-HA/P66 scaffold and bone tissue is blurred. Furthermore, the histological result also verifies the alterations in micro-CT, and bone tissue grows in the bone tunnel with n-HA/P66 scaffold implanted while few in the CD group. The CD results in a lack of mechanical support in the femoral head subchondral bone and bone tunnel high stress. The n-HA/P66 scaffold implantation can provide mechanical support and relieve high stress induced by CD. The n-HA/P66 scaffold can treat femoral head necrosis and provide the bone tissue growth scaffold for the femoral head after CD to promote bone tissue regeneration.

Influence of less invasive hip preservation surgery on subsequent hip arthroplasty for osteonecrosis of the femoral head.

ABSTRACTThe purpose of this study was to evaluate the outcomes of total hip arthroplasty (THA) following less invasive hip-preserving procedures (LIHPs) and present a critical overview of the literature to aid in better result interpretation. The search time was from the establishment of the database to September 2021, and the outcome indicators were extracted and analyzed by Cochrane Collaboration Review Manager software (RevMan version 5.4). Finally, 10 articles were included in this meta-analysis by searching Chinese databases and English databases. Three of them were published in Chinese, and the remaining studies were published in English. LIHP was further divided into the tantalum rod implantation group and the non-tantalum rod implantation group. The results showed that prior tantalum rod implantation increased the difficulty of conversion to THA, which was reflected mainly in the longer operative time [weighted mean difference (WMD) = 24.50, 95% confidence interval (CI) = 14.09–34.91, P < 0.00001] and greater intraoperative blood loss (WMD = 114.74, 95% CI = 33.52–195.96, P = 0.006), while no significant difference was found between the non-tantalum rod implantation group and the control group. Simultaneously, easier intraoperative fracture [odds ratio (OR) = 5.88, 95% CI = 0.93–37.05, P = 0.06] and stem malalignment (OR = 4.17, 95% CI = 1.18–14.71, P = 0.03) in the LIHP group tended to be observed than in the control THA group. However, there was no significant difference in cup anteversion and inclination angle, ectopic ossification, postoperative Harris Hip Score and survivorship between the LIHP group and the control group. Although LIHP increased the difficulty of the conversion to THA, it does not detrimentally affect the clinical results of subsequent THA in the mid-term follow-up.

Analysis of peripheral bone reconstruction after the failure of hip osteonecrosis treatment with porous tantalum rod implantation.

Failure of porous tantalum rod (PTR) implantation in treating early osteonecrosis of femoral head (ONFH) has been frequently reported, but the underlying mechanism remains uncertain, which raised the concern of its efficacy. The study aimed to discuss the underlying mechanism from the perspectives of bone reconstruction and pathological changes. Five patients with PTR implantation experienced total hip arthroplasty (THA) due to recurrent pain, whose femoral heads were collected as "tantalum group." Normal (fracture) and necrotic femoral heads were respectively collected (both n = 5) after THA. The bone quality and structure, biomechanical properties, and histopathological features were analyzed by micro-CT scanning, mechanical measurement, and histological examination. Both the tantalum group and necrotic group had significantly poorer bone quantity and quality than the normal group. Three-dimensional imaging reconstruction showed that the trabeculae of the tantalum group were poorest in quality. Significant differences in terms of bone quality, structure, and biomechanical properties were present between the inside and outside regions around PTR, which revealed abnormal bone reconstruction. Biomechanical analysis revealed inferior properties in the tantalum group and necrosis group. H&E staining demonstrated neutrophil infiltration among the peripheral trabeculae around PTR, and the inflammation cells were significantly more abundant than that in the normal and necrosis groups. Abnormal bone reconstruction around PTR was an important cause for failure of PTR implantation in the treatment of ONFH, which was related to biomechanical stress distribution and chronic inflammation infiltration. Insufficient biomechanical support and inflammatory trabeculae edema might account for the recurrent pain.

Efficacy of various core decompression techniques versus non-operative treatment for osteonecrosis of the femoral head: a systemic review and network meta-analysis of randomized controlled trials

BackgroundVarious Joint-preserving therapy (JPT) methods have been performed and tried in recent decades, but their results and efficacy were inconsistent and controversial. The purpose of this study is to evaluate its effectiveness and whether there are statistical differences in treatment between different interventions based on published RCT studies.MethodsFollowing the PRISMA-NMA checklist, Medline, EMBASE, Web of Science, and Cochrane Library databases were searched and collected related RCT studies. The sources were searched from inception up to October 30, 2020. The primary outcomes including the rate of radiographic progression and conversion to THA and the secondary outcome -Harris Hip Scores (HHS) were extracted and compared in a Network meta-analysis.ResultsSeventeen RCT studies involving 784 patients (918 hips) with seven interventions including CD (core decompression), CD + BG (bone graft), CD + TI (tantalum rod implantation), CD + CT (Cell therapy), CD + BG + CT, VBG (vascularized bone graft), and nonsurgical or conservative treatment for ONFH were evaluated. In the radiographic progression results, CD + CT showed a relatively better result than CD, CD + BG and non-surgical treatment, the surface under the cumulative ranking curve (SUCRA) plot displayed that CD + CT (96.4%) was the best, followed by CD (64.1%).In conversion to THA results, there were no significant differences between the JPT methods and non-surgical treatment. In HHS, there was also no significant difference, other than CD + BG showed a statistical difference than non-surgical treatment only in terms of Cis, but the SUCRA was highest in non-surgical treatment (80.5%) followed by CD + CT (72.8%).ConclusionsThis Net-work meta-analysis demonstrated that there was no statistical difference in the outcome of radiographic progression and conversion to THA, also in HHS, other than CD + CT showed a relatively superior result in radiographic progression than nonsurgical treatment, namely, it’s maybe an effective method for delaying disease progression or reducing disease development based on current evidence.

Porous tantalum implant for treatment of early-stage osteonecrosis of the femoral head: a minimum 5-year follow-up study

BackgroundTo evaluate the survival rate of porous tantalum rod implantation in the treatment of osteonecrosis of the femoral head (ONFH), evaluate its clinical effect and imaging results.MethodsFrom January 2008 to December 2013, porous tantalum rod implantation for ONFH was performed in two institutions. Statistical analysis of operation data, including operation time, blood loss and blood transfusion were recorded.Results52 hips received complete follow-up, the average follow-up time was 85.7 months (60–132 months). 24 hips turned to THA at the end of follow-up (46.2%), the average time was 44.3 ± 32.8 months, and the average Harris hip score before THA was 57.1 ± 7.6. Cox proportional-hazards model revealed that Association Research Circulation Osseous (ARCO) stage (P = 0.017), bone marrow edema (P = 0.006) and age > 40 years (P = 0.043) were independent risk factors for conversion to THA.ConclusionARCO stage, age and bone marrow edema were risk factors for the failure of porous tantalum rod implantation to convert to THA.

Efficacy and Safety of Stem Cell Combination Therapy for Osteonecrosis of the Femoral Head: A Systematic Review and Meta-Analysis.

Background The treatment results of core decompression (CD) and biomechanical support are not always satisfactory in osteonecrosis of the femoral head (ONFH). Stem cell therapy has been incorporated into traditional treatment in order to promote bone regeneration. The efficacy and safety of stem cell therapy combined with CD or biomechanical support on advanced and long-term patients with ONFH were unknown. The aim of this study was to assess whether stem cell combination therapy is superior to single CD or porous tantalum rod implantation treatment in ONFH. Methods A systematic search of the literature was performed to evaluate all included randomized controlled trials (RCTs) on stem cell combination therapy for patients with ONFH in PubMed, Cochrane Library, Web of Science, and Embase sites. We assessed the quality and risk of bias for the included studies. And the outcomes of Harris hip score (HHS), visual analogue scale (VAS), and adverse events were statistically analyzed. Results We included 10 randomized controlled trials, containing a total of 498 patients with 719 hips. Stem cell therapy combined with CD versus CD alone for HHS of ONFH was different (MD = 8.87, 95% CI = [5.53, 12.22], P < 0.00001). The combination of stem cell therapy and CD can effectively improve HHS. Similarly, the VAS of the stem cell combination therapy group also differed compared with the control group (MD = −14.07, 95% CI = [−18.32, −9.82], P < 0.00001). The result showed that stem cell combination therapy can relieve the pain of patients with ONFH. There was no significant difference in adverse response outcome events between the combination therapy group and the control group (RR = 1.57, 95% CI = [0.62, 3.97], P = 0.34). Conclusions Stem cell therapy combined with core decompression is an effective and feasible method with few complications in the clinical treatment of early-stage ONFH. Even in the combination of porous tantalum rod implantation and peripheral blood stem cells, stem cell combination therapy is superior to single biomechanical support treatment. But high-quality, large-sample, multicenter, and long-term follow-up RCTs are still needed to corroborate the efficacy and safety of stem cell combination therapy in ONFH treatment.

Porous tantalum rod implantation is associated with low survival rates in patients with type C2 osteonecrosis of the femoral head but has no effect on the clinical outcome of conversion total hip arthroplasty: a retrospective study with an average 8-year follow-up

BackgroundOur study aimed to investigate the clinical outcomes and survival rates following porous tantalum rod surgery (PTRS) and conversion total hip arthroplasty (THA) subsequent to failed PTRS.MethodsA total of 38 subjects (40 hips) with osteonecrosis of the femoral head (ONFH) were included in this retrospective study between January 2008 and December 2011. All subjects were evaluated before surgery by using the Association Research Circulation Osseous (ARCO) classification system, the Japan Investigation Committee (JIC) classification and the Harris hip score (HHS). The endpoint of this study was set as final follow-up (including the survival time of PTRS and conversion THA). The rates of radiological progression were also evaluated. Patients who received conversion THA were further followed and compared to a control group of 58 patients with ONFH who underwent primary THA.ResultsThe mean follow-up time was 120.7 ± 9.2 (range, 104–143) months, and the overall survival rate was 75% at 96 months (ARCO stage II: 81.5%; stage III: 38.5%; JIC type C1: 83.3%; C2: 30%). The HHS before surgery was 59 (55–61), in contrast to 94 (91–96) at 96 months follow-up (P < 0.01). HHS in stage III show a significant poorer result compared to stage II at 24 months. HHS in Type C2 group show no significant difference compared to HHS before surgery at 24 and 60 months follow up (P = 0.91, P = 0.30). Twelve hips requiring secondary THA were followed for 66.9 ± 31.7 months, and control hips that underwent primary THA was followed for 75.4 ± 14.9 months. The HHS in the conversion group was 89 (86–93) and that in the primary THA group was 92 (79–95, P = 0.09) at the 5-year follow-up.ConclusionIn the mid-term follow-up, porous tantalum implants showed an encouraging survival rate in symptomatic patients in early stages (ARCO stage II) or with limited necrotic lesions (JIC type C1). In addition, our results did not demonstrated any difference between primary THA and conversion THA.

Current Treatment Modalities for Osteonecrosis of Femoral Head in Mainland China: A Cross-Sectional Study.

ObjectiveTo investigate the application of treatment modalities for patients with osteonecrosis of the femoral head (ONFH) in mainland China.MethodsThis cross‐sectional study was based on the online application of China Osteonecrosis of the Femoral Head Database (CONFHD). Between July 2016 to December 2018, the CONFHD program planned to recruit ONFH patients from 12 administrative areas across mainland China. Real‐world medical records of treatment regimens for these patients, including surgeries and prescriptions, were approved to upload to the CONFHD application for further analysis. The surgeries performed on these patients were classified into total hip arthroplasty and hip‐preserving procedures, and the latter was further classified into core decompression, bone grafting, and tantalum rod implantation. Prescription medications were classified into chemical medicine and Chinese herbal medicine (CHM); chemical medicine was further classified according to their chemical compounds, and CHM was classified according to therapeutic functions based on traditional Chinese medicine theory. Descriptive analysis was performed to summarize the application of different treatment regimens on the overall sample.ResultsA total of 1491 patients (2381 hips) who fulfilled the protocol criteria were included. There were 1039 males and 452 females with a mean age of 47.29 ± 12.69 years. The causes of ONFH were alcoholism in 642 patients (43%), corticosteroid in 439 patients (29%), trauma in 239 patients (16%), and idiopathic ONFH in 171 patients (11%). Operative treatments (including total hip arthroplasty and hip‐preserving procedures) were performed on 49% of patients (43% of hips), chemical medicine therapy (including bisphosphonate, statins, and prostacyclin) was given to 37% of patients (37% of hips), and CHM was administrated to 72% of patients (75% of hips). The aforementioned interventions were not always used alone, since 47% of patients (52% of hips) received combined regimens with multiple interventions. Among hips treated by surgery, all hips with ARCO stage IV ONFH received THA (305 hips), and THA was also performed on 63 hips with stage II ONFH. Over half of hips with stage I (81%), II (91%), and III (92%) ONFH had received pharmacological treatments. Prostacyclin and bisphosphonate were the top two most prescribed medicines used alone. CHM therapies with multiple CHM functions were more commonly prescribed.ConclusionCurrent treatment modalities for ONFH patients in mainland China include operative treatment, chemical medicine, and CHM. Combined regimens with different treatment modalities are common in real‐world clinical practices.

The Comparative Analysis of Antegrade Versus Retrograde Approach for a Failed Porous Tantalum Rod Removal During Conversion to Total Hip Arthroplasty.

BackgroundThe failure of porous tantalum rods applied to patients with osteonecrosis of the femoral head (ONFH) has been increasingly reported during the last few years. Very few studies have reported methods for implant removal. This study aimed at comparing 2 procedures used for the removal of a failed tantalum rod during conversion to total hip arthroplasty (THA).Material/MethodsA total of 65 patients (65 hips), who underwent THA after failed implantation of a tantalum rod between June 2007 and December 2016, were retrospectively evaluated. These patients were classified into 2 groups depending on whether the antegrade approach (removal of the tantalum rod from the tip to the butt at the lateral femoral cortex, n=27) or retrograde approach (removal of the tantalum rod from the butt at the lateral femoral cortex to the proximal tip, n=38) was used for rod extraction. These 2 groups were compared for incision length, operation time, blood loss, fracture, tantalum debris, Harris hip scores, and the presence of osteolysis and/or radiolucency.ResultsThese 2 groups did not present any significant differences in terms of Harris hip score and incision length. However, the operation time (P=0.000), blood loss (P=0.000), amount of tantalum debris (P=0.000), and presence of radiolucency (P=0.046) were greater for the retrograde approach than for the antegrade approach.ConclusionsThe risk of conversion to THA following failed tantalum rod implantation is high. In such cases, the antegrade procedure was found to be a simple and efficient method for removing the trabecular metal rod with the use of a trephine.

Comparison of core decompression and porous tantalum rod implantation with conservative treatment for avascular necrosis of the femoral head: A minimum 18 month follow-up study.

Porous tantalum rod implantation is a novel surgical method that is used to treat avascular necrosis (AVN) of the femoral head (hip). In the present study, the results of core decompression and tantalum rod implantation were compared with non-surgical treatment for AVN, and the survivorship of the femoral head was evaluated. In total, 60 patients with AVN femoral head were recruited and analysed. Non-surgical treatment was selected by 30 patients (41 hips), 7 with a Ficat score of I and 23 with a score of II. Non-surgical treatment included celecoxib, salvia miltiorrhiza and tetramethylypyrazine and a reduction in weight-bearing activities. Surgical treatment and porous tantalum rod implantation were selected by 30 patients (41 hips), 10 with a Ficat score of I and 20 with a score of II. After follow-up (average: 33.5 months), patients were evaluated by assessing post-operative complications, radiology, hip survivorship and Harris hip score. In the surgical group, pre-operative symptoms were significantly alleviated. No complications, including infection, delayed healing or fractures were reported. Final follow-up rates of femoral head survivorship were 4.9% in the non-surgical group and 36.7% in the surgical group. The Harris hip score was significantly improved following surgery when compared with non-surgical treatment (P<0.05). The results indicated that core decompression and porous tantalum rod implantation are beneficial short- and mid-term treatment methods for AVN of the femoral head.

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.

Clinical effects of the implantation of porous tantalum rod under three-dimensional C-arm positioning in treating ARCO I-II non-traumatic necrosis of the femoral head

Objective To evaluate the clinical effects of the implantation of porous tantalum rod under three-dimensional (3D) C-arm positioning in the treatment of ARCO I and II non-traumatic femoral head necrosis. Methods Fifty patients (58 hips, 39 males and 11 females, mean age 33.52 years) with non-traumatic femoral head in ARCO I-II were included from January 2009 to December 2011. All patients received implantation of porous tantalum rod. The 3D C-arm X-ray positioning was used in 24 patients (29 hips), while traditional C-arm X-ray positioning was performed in the other patients. The visual analogue scale (VAS), Harris score and superior rate were evaluated at 0.5, 1, 2, and 4 years after the surgery. Total hip arthroplasty was regarded as the end event for survival rate. Results In the 3D C-arm X-ray positioning group, the VAS score decreased from 7.17±1.00 points preoperatively to 2.38±0.86 points at half year, to 2.10±1.40 points at 1 year, to 2.38±1.66 points at 2 years, and to 2.21±1.47 points at 4 years postoperatively (F=98.78, P=0.00). Meanwhile, the Harris score increased significantly from 73.97±3.49 points preoperatively to 89.90±1.93, 89.93±3.26, 89.21±5.83, 88.57±5.70 points at the follow up, respectively (F=84.35, P=0.00). According to the analysis of the pre-operative and post-operative image data, there was no significant difference in progress in the ARCO staging at 23 hips duration the follow-up. Four hips were developed to ARCO III and two hips to ARCO II. Thus, the success rate of operation was 79% (23/29). There were two hips underwent total hip arthroplasty, so the survival rate of femoral head was 93% (27/29). The trend of VAS score and Harris score in the C-arm X-ray positioning group was in accordance with the 3D C-arm X-ray positioning group but without statistically significant difference (P>0.05). The operation duration 31.38±3.96 min, blood loss 36.72±5.59 ml, the ratio of distance of metal rod to bone cortex in femoral neck 0.48±0.10, and the distance of mental rod to center of necrosis 0.18±0.07 cm in 3D C-arm X-ray positioning group was superior to C-arm X-ray positioning group (respectively 41.97±4.64 min, 41.49±4.46 ml, 0.46±0.06, 0.23±0.10 cm, P<0.05). Conclusion The implantation of tantalum rod in treating ARCO I-II non-traumatic femoral head necrosis can increase the function of hip joint, relieve the symptoms of necrosis of femoral head, alleviate the progress of femoral head necrosis in X-ray, and obtain a higher survival rate. The 3D C-arm positioning in surgical operation could improve the accuracy and safety of surgery. Key words: Femur head necrosis; Tantalum; Imaging, three-dimensional; X-rays; Radiography

Three-dimensional finite element analysis of silk protein rod implantation after core decompression for osteonecrosis of the femoral head

BackgroundSeveral methods are available for the treatment of early-stage osteonecrosis of the femoral head. Core decompression with implantation is a widely-used treatment. However, no single implant is recognized as the most effective way to prevent disease progression. Silk has high strength and resiliency. This study explored the possibility of a strong and resilient silk protein biomaterial as a new alternative implant.MethodsWe investigated the biomechanical properties of the silk protein material by regular compression, torsion, and three-point bending tests. We established three-dimensional finite element models of different degrees of femoral head osteonecrosis following simple core decompression, fibula implantation, porous tantalum rod implantation, and silk protein rod implantation. Finally, we compared the differences in displacement and surface stress under load at the femoral head weight-bearing areas between these models.ResultsThe elastic modulus and shear modulus of the silk protein material was 0.49GPa and 0.66GPa, respectively. Three-dimensional finite element analyses demonstrated less displacement and surface stress at the femoral head weight-bearing areas following silk protein rod implantation compared to simple core decompression (p < 0.05), regardless of the extent of osteonecrosis. No differences were noted in the surface deformation or surface stress of the femoral head weight-bearing areas following silk protein rod, fibula or tantalum rod implantation (p > 0.05).ConclusionsWhen compared with simple core decompression, silk protein rod implantation demonstrated less displacement and surface stress at the femoral head weight-bearing area, but more than fibula or tantalum rod implantation. Similar effects on the surface stress of the femoral head between the silk rod, fibula and tantalum rod implantations, combined with additional modifiable properties support the use of silk protein as a suitable biomaterial in osteonecrosis surgery.

Peripheral Blood Stem Cell Therapy Does Not Improve Outcomes of Femoral Head Osteonecrosis With Cap‐Shaped Separated Cartilage Defect

A combination treatment with porous tantalum rod implantation and intra-arterial infusion of peripheral blood stem cells (PBSCs) provides a promise for treating early and intermediate stages of osteonecrosis of the femoral head (ONFH). However, its clinical indications and application restrictions remain unclear. This study aims to determine the clinical, histological, and radiological outcomes of a combination treatment using mechanical support and a targeted intra-arterial infusion of PBSCs for painful ONFH with a cap-shaped separation (CSS) cartilage defect. Compared with the standard pain management (control group), this combination treatment did not improve the Harris Hip Score (HHS) at 36 months. Micro-CT and histologic analyses showed severe focal destruction in all CSS-ONFH femoral heads in both the combination and control groups. Femoral heads showed a higher percentage of bone lesions in the combination treatment group than in the control group. There was no significant difference in osteoclast number in the subchondral bone areas between the two groups. A high level of expression of inflammatory cytokines, including tumor necrosis factor-α and interleukin-1β, was detected in blood vessels around the subchondral bone in both groups. The RANKL/OPG (receptor activator of the nuclear factor-kB ligand/osteoprotegerin) ratio was also similar between the control and combination treatment groups. Our results indicate that this combination treatment is not an effective method for the treatment of patients with painful CSS-ONFH. Moreover, this combination treatment did not inhibit inflammatory osteoclastogenesis in patients with more advanced disease. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:269-276, 2020.

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

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. 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. 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. 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.

Vascular bundle transplantation combined with porous bone substituted scaffold for the treatment of early-stage avascular necrosis of femoral head

Various reasons leading to disruption of blood supply will result in avascular femoral head necrosis. Decompression of lesion area, structural support to subchondral bone, and rebuilding of blood supply system are the keys for a successful hip preserve surgery. Reconstruction of local vascular network is always a huge challenge in clinical. Based on tantalum rod implantation and free vascularized fibular grafting, we propose the combined application of vascular bundle transplantation and porous bone substitute scaffold implantation as a potential novel treatment method. It may simultaneously achieve decompression, support and blood supply reconstruction. The hypothesis provides some new ideals and possibilities for solving this clinical problem of femoral head necrosis.

Total hip arthroplasty following failure of tantalum rod implantation for osteonecrosis of the femoral head with 5- to 10-year follow-up

BackgroundTotal hip arthroplasty (THA) with failure of tantalum rod implant for osteonecrosis of the femoral head (ONFH) will be the only choice for patients. However,it remains unknown whether tantalum rod implantation has an adverse effect on the survival time of implants following conversion to THA. The aim of this study was to retrospectively evaluate the clinical and radiographic outcomes of conversion to THA in patients who were previously treated with implantation of a tantalum rod.MethodsThis study included 31 patients (39 hips), who underwent conversion to THA due to failure of core decompression with an implanted tantalum rod. Among these 31 patients, 26 patients were male and five patients were female. The mean age of these patients was 49.3 years old (range: 36–64 years old). The control group included 33 patients (40 hips), who underwent total hip replacement without tantalum rod implantation. The hip Harris score, implant wear, osteolysis, radiolucencies and surgical complications were recorded during the follow-up. The distribution of tantalum debris in the proximal, middle and distal periprosthetic femoral regions, radiolucent lines and osteolysis were analyzed on post-operative radiographs.ResultsThere were no significant differences in Harris score, liner wear and complications between the two groups (P > 0.05). Osteolysis and radiolucent lines more likely occurred in patients with tantalum debris distributed in three regions than in one or two regions (P < 0.05).ConclusionsThe mid-term clinical outcome of patients who underwent THA with tantalum rod implantation was not different from those without a tantalum rod, suggesting that tantalum debris did not increase the liner wear rate. However, the distribution of periprosthetic tantalum debris in the proximal, middle and distal femoral regions may increase the risk of femoral osteolysis and radiolucent lines.

Total hip arthroplasty following failure of core decompression and tantalum rod implantation.

One method of femoral head preservation following avascular necrosis (AVN) is core decompression and insertion of a tantalum rod. However, there may be a high failure rate associated with this procedure. The purpose of this study was to document the clinical and radiological outcomes following total hip arthroplasty (THA) subsequent to failed tantalum rod insertion. A total of 37 failed tantalum rods requiring total hip arthroplasty were identified from a prospective database. There were 21 hips in 21 patients (12 men and nine women, mean age 37 years, 18 to 53) meeting minimum two year clinical and radiographic follow-up whose THAs were carried out between November 2002 and April 2013 (mean time between tantalum rod implantation and conversion to a THA was 26 months, 6 to 72). These were matched by age and gender to individuals (12 men, nine women, mean age 40 years, 18 to 58) receiving THA for AVN without prior tantalum rod insertion. There were no functional outcome differences between the two groups. Tantalum residue was identified on all post-operative radiographs in the tantalum group. Linear wear rates were comparable between groups with no evidence of catastrophic wear in either group. In the short term, tantalum rod implantation does not demonstrate an adverse effect on subsequent total joint replacement surgery. There is however, a high rate of retained tantalum debris on post-operative radiographs and thus there is an unknown risk of accelerated articular wear necessitating longer term study. Cite this article: Bone Joint J 2016;98-B:1175-9.

Porous tantalum rods improve the hip joint function of patients with avascular necrosis of the femoral head after femoral neck fracture surgery: study protocol of a randomized controlled trial

Background: After femoral neck fracture, insufficient blood supply to the femoral head can cause avascular necrosis of this region. This can lead to increased treatment difficulty, and may greatly influence the recovery of hip joint function. Core decompression with bone grafting is a common treatment for avascular necrosis of the femoral head. An implanted porous tantalum rod, which is a bone trabecula-like metal implant that is used to support the weight-bearing area of necrotic bone, can prevent further collapse of the necrotic area. This strategy has led to favorable effects in the early treatment of avascular necrosis of the femoral head. However, few randomized controlled studies have reported on porous tantalum rod implantation for treatment of avascular necrosis of the femoral head after femoral neck fracture surgery. We hypothesized that, compared with core decompression alone, core decompression with porous tantalum rod implantation would have a more beneficial effect of the hip joint function of patients with avascular necrosis of the femoral head after femoral neck fracture surgery. Methods/Design: This is a prospective, single-center, randomized controlled, open-label trial, which will be performed in the Department of Orthopedic Trauma, Qinghai University Affiliated Hospital, China. A total of 100 patients with avascular necrosis of the femoral head after femoral neck fracture surgery will be randomly assigned to undergo core decompression and porous tantalum rod implantation (experimental group, n = 50) or core decompression only (control group, n = 50). All patients will be followed up for 1 year. The primary outcome measure is the percentage of patients (of the total number of patients in each group) whose hip joint function is graded as excellent as per Harris hip scores 12 months after surgery. This value will be used to evaluate the recovery of hip joint function. Secondary outcome measures include (1) the percentage of patients with excellent hip joint function, prior to and 1 and 6 months after surgery (of the total number of patients in each group); (2) hip joint pain score on a Visual Analogue Scale prior to and 1, 6, and 12 months after surgery, which will be used to evaluate the severity of pain; (3) the percentage of patients presenting with femoral head collapse, prosthesis loosening, and peri-prosthesis infection 6 and 12 months after surgery, which will be used to evaluate the biocompatibility of the biomaterial with the host site; (4) incidence of complications 6 and 12 months after surgery, which will be used to evaluate the safety of porous tantalum rod implantation. Discussion: This study is powered to validate the biocompatibility and therapeutic effects of porous tantalum rods in the treatment of avascular necrosis of the femoral head after femoral neck fracture, with the hopes that this novel surgical method represents a superior treatment for this disease. Trial registration: ClinicalTrial.gov identifier: NCT02877472; registered on 19 August 2016. Ethics: This study protocol has been approved by the Medical Ethics Committee of Qinghai University Affiliated Hospital of China (approval number: QHY1016B) and will be performed in accordance with the guidelines of the Declaration of Helsinki, formulated by the World Medical Association. Informed consent: Signed informed consent regarding trial procedure and treatment will be obtained from each patient.