Subtalar arthroereisis with metallic implant is a safe and effective treatment for pediatric patients with symptomatic flexible flatfeet. A 10-year clinical and radiographic follow-up.

BACKGROUND: Subtalar arthroereisis (SA) is an increasingly applied minimally invasive approach for flexible flat foot (FFF) not responsive to conservative treatment. This study aimed at evaluating the long-term clinical and radiographic outcomes of SA in pediatric patients with symptomatic FFF. METHODS: Thirty-seven patients (11.9 ± 1.6yy) underwent SA (74 feet), with outcomes assessed after a mean 10-year follow-up. Pain, quality of life, foot functionality, and alignment were evaluated using validated tools and radiographic parameters, calculated on weightbearing x-rays pre- and post-operatively. RESULTS: Clinical outcomes reached excellent postoperative results (FFI: 9.1, AOFAS: 94.5) with a low 0.9 NRS pain (p < 0.01) and a 92 % satisfaction. All radiographic parameters improved significantly towards normal values: CP 17.5 ± 3.9, MA 4.3 ± 5.8, TCA 42.8 ± 6.2, TNCA 21.1 ± 8.5, TNU% 26.6 ± 8.4 (all p < 0.01). CONCLUSIONS: SA with a metallic endosinotarsal device provided significant long-term clinical and radiographic improvements, with low complication rates and high patient satisfaction, supporting its efficacy as a treatment option for pediatric symptomatic FFF. LEVEL OF EVIDENCE: IV.

Nerve Regeneration with a Scaffold Incorporating an Absorbable Zinc-2% Iron Alloy Filament to Improve Axonal Guidance.

Peripheral nerve damage that results in lost segments requires surgery, but currently available hollow scaffolds have limitations that could be overcome by adding internal guidance support. A novel solution is to use filaments of absorbable metals to supply physical support and guidance for nerve regeneration that then safely disappear from the body. Previously, we showed that thin filaments of magnesium metal (Mg) would support nerve regeneration. Here, we tested another absorbable metal, zinc (Zn), using a proprietary zinc alloy with 2% iron (Zn-2%Fe) that was designed to overcome the limitations of both Mg and pure Zn metal. Non-critical-sized gaps in adult rat sciatic nerves were repaired with silicone conduits plus single filaments of Zn-2%Fe, Mg, or no metal, with autografts as controls. After seventeen weeks, all groups showed equal recovery of function and axonal density at the distal end of the conduit. The Zn alloy group showed some improvements in early rat health and recovery of function. The alloy had a greater local accumulation of degradation products and inflammatory cells than Mg; however, both metals had an equally thin capsule (no difference in tissue irritation) and no toxicity or inflammation in neighboring nerve tissues. Therefore, Zn-2%Fe, like Mg, is biocompatible and has great potential for use in nervous tissue regeneration and repair.

Metallic implant-related osteosarcoma.

Orthopedic metallic prostheses are commonly used in the current practice of orthopedic surgery. Although, biomaterials used in these implants are generally considered to be biologically inert, there have been consequences of foreign body reactions and potential carcinogenesis. Majority of implant-related malignancies are high grade, and develop in bone or soft tissue around the implant site. No clear association has been identified between the biomaterial implanted and the type of sarcoma. We report the case of a 36-year-old male who underwent intramedullary nailing of femur for mid-shaft fracture secondary to trauma and presented with osteogenic sarcoma of femur 14 months later.

Fixation of patella fractures with metallic implants is associated with a significantly higher risk of complications and re-operations than non-metallic implants: a systematic review and meta-analysis.

PURPOSE: The use of metallic implants for the treatment of patella fractures often involves complications related to the hardware. As a result, there has been a considerable focus on the use of non-metallic implants. The aim of this study was to determine the differences in clinical outcomes, including the rates of complications and re-operations following the surgical management of patellar fractures with metallic versus non-metallic implants. METHODS: The systematic review was conducted in accordance with PRISMA guidelines. Two investigators independently applied the search strategy to PubMed, SCOPUS, Google Scholar, and Cochrane databases, limited to publications between 1st January 2000 to 30st September 2021. The search strategy identified studies in which there was a comparison between the clinical outcome of the metallic and non-metallic fixation. Meta-analysis was conducted according to the Cochrane Collaboration and Quality of Reporting of Meta-Analysis (QUORUM) guidelines. RESULTS: A total of 19 studies were selected for the systematic review and seven studies for the meta-analysis. Two hundred ninety-sixt patients formed the pooled study population for the meta-analysis. The outcomes evaluated in the meta-analysis were range of motion (ROM), complications, and re-operation rates. There was no significant difference between groups regarding ROM, but the risk ratio (RR) of re-operation (RR 0.19, 95% CI [0.09-0.41]) and complications (RR 0.30, 95% CI [0.17-0.55]) was significantly in favor of fixation with non-metallic implants. CONCLUSION: The use of non-metallic implants for fixation of patella fractures was associated with significantly lower risk of complications and re-operations than fixation with metallic implants, without any difference between groups with respect to the final range of motion or functional outcome measures.

Impact of degradable magnesium implants on osteocytes in single and triple cultures.

In vitro triple cultures of human primary osteoblasts, osteocytes and osteoclasts can potentially help to analyze the effect of drugs and degradation products of biomaterials as a model for native bone tissue. In the present study, degradation products of Magnesium (Mg), which has been successfully applied in the biomedical field, were studied with respect to their impact on bone cell morphology and differentiation both in osteocyte single cultures and in the triple culture model. Fluorescence microscopic and gene expression analysis, analysis of osteoclast- and osteoblast-specific enzyme activities as well as osteocalcin protein expression were performed separately for the three cell types after cultivation in triple culture in the presence of extracts, containing 5 and 10 mM Mg2+. All three cell species were viable in the presence of the extracts and did not show morphological changes compared to the Mg-free control. Osteoblasts and osteoclasts did not show significant changes in gene expression of ALPL, BSPII, osteocalcin, TRAP, CTSK and CA2. Likewise on protein level, no significant changes in ALP-, TRAP-, CTSK- and CAII activities were detected. Osteocytes showed a significant downregulation of MEPE, which codes for a protein playing an important role in regulation of phosphate homeostasis by osteocytes. This study is the first to analyze the effects of Mg degradation products on primary osteocytes in vitro, both in single and triple culture. Even if promoting effects on the three examined bone cell species were not found in the applied triple culture setup, it was shown, that Mg degradation products do not interfere with the activity of osteoblasts, osteoclasts and osteocytes in vitro.

In Vivo Antibacterial Efficacy of Antimicrobial Peptides Modified Metallic Implants─Systematic Review and Meta-Analysis.

Biomaterial-associated infection is difficult to detect and brings consequences that can lead to morbidity and mortality. Bacteria can adhere to the implant surface, grow, and form biofilms. Antimicrobial peptides (AMPs) can target and kill bacterial cells using a plethora of mechanisms of action such as rupturing the cell membrane by creating pores via depolarization with their cationic and amphipathic nature. AMPs can thus be coated onto metal implants to prevent microbial cell adhesion and growth. The aim of this systematic review was to determine the potential clinical applications of AMP-modified implants through in vivo induced infection models. Following a database search recently up to 22 January 2022 using PubMed, Web of Science and Cochrane databases, and abstract/title screening using the PRISMA framework, 24 studies remained, of which 18 were used in the random effects meta-analysis of standardized mean differences (SMD) to get effect sizes. Quality of studies was assessed using SYRCLE's risk of bias tool. The data from these 18 studies showed that AMPs carry antibacterial effects, and the meta-analysis confirmed the favorited antibacterial efficacy of AMP-coated groups over controls (SMD -1.74, 95%CI [-2.26, -1.26], p < 0.00001). Subgroup analysis showed that the differences in effect size are random, and high heterogeneity values suggested the same. HHC36 and vancomycin were the most common AMPs for surface modification and Staphylococcus aureus, the most tested bacterium in vivo. Covalent binding with polymer brush coating and physical layer-by-layer incorporation of AMPs were recognized as key methods of incorporation to achieve desired densities. The use of fusion peptides seemed admirable to incorporate additional benefits such as osteointegration and wound healing and possibly targeting more microbe strains. Further investigation into the incorporation methods, AMP activity against different bacterial strains, and the number of AMPs used for metal implant surface modification is needed to progress toward potential clinical application.

A comprehensive review on metallic implant biomaterials and their subtractive manufacturing.

There is a tremendous increase in the demand for converting biomaterials into high-quality industrially manufactured human body parts, also known as medical implants. Drug delivery systems, bone plates, screws, cranial, and dental devices are the popular examples of these implants - the potential alternatives for human life survival. However, the processing techniques of an engineered implant largely determine its preciseness, surface characteristics, and interactive ability with the adjacent tissue(s) in a particular biological environment. Moreover, the high cost-effective manufacturing of an implant under tight tolerances remains a challenge. In this regard, several subtractive or additive manufacturing techniques are employed to manufacture patient-specific implants, depending primarily on the required biocompatibility, bioactivity, surface integrity, and fatigue strength. The present paper reviews numerous non-degradable and degradable metallic implant biomaterials such as stainless steel (SS), titanium (Ti)-based, cobalt (Co)-based, nickel-titanium (NiTi), and magnesium (Mg)-based alloys, followed by their processing via traditional turning, drilling, and milling including the high-speed multi-axis CNC machining, and non-traditional  abrasive water jet machining (AWJM), laser beam machining (LBM), ultrasonic machining (USM), and electric discharge machining (EDM) types of subtractive manufacturing techniques. However, the review further funnels down its primary focus on Mg, NiTi, and Ti-based alloys on the basis of the increasing trend of their implant applications in the last decade due to some of their outstanding properties. In the recent years, the incorporation of cryogenic coolant-assisted traditional subtraction of biomaterials has gained researchers' attention due to its sustainability, environment-friendly nature, performance, and superior biocompatible and functional outcomes fitting for medical applications. However, some of the latest studies reported that the medical implant manufacturing requirements could be more remarkably met using the non-traditional subtractive manufacturing approaches. Altogether, cryogenic  machining among the traditional routes and EDM among the non-traditional means along with their variants, were identified as some of the most effective subtractive manufacturing techniques for achieving the dimensionally accurate and biocompatible metallic medical implants with significantly modified surfaces.

No difference in clinical and radiological outcomes following fixation of transverse patella fractures with either suture tape or metallic cerclage: A retrospective comparative study.

INTRODUCTION: Several surgical techniques have been proposed for the treatment of patellar fractures. The aim of this study is to compare the clinical efficacy and complication rates of treatment using suture tape circumferential cerclage (STCC) and metallic wire circumferential cerclage (MWCC) for the surgical treatment of displaced transverse patellar fractures (TPFs). HYPOTHESIS: The hypothesis is that the use of the suture tape would be associated with a significantly lower rate of re-operation than metallic cerclage but no differences in other clinical outcomes. PATIENTS AND METHODS: A retrospective comparative analysis of the clinical outcomes of consecutive patients undergoing fixation of TPFs with either MWCC or STCC between January 2017 and December 2018 was undertaken. All patients underwent evaluation with standardised radiographs at one, three, and six months after surgery to determine rates of union, non-union, loss of fixation and malunion. All patients underwent a final clinical evaluation at 18 months postoperatively to evaluate clinical scores and complications. RESULTS: A total of 26 patients were included in the study. Thirteen patients underwent STCC and 13 underwent MWCC. There were no complications in the STCC group. In the MWCC group, one patient underwent hardware removal at 2 months postoperatively due to painful prominence. There was no significant difference in re-operation rates between the STCC and MWCC groups (p=1). There were no cases of non-union, malunion or loss of fixation throughout the series. At the final clinical follow-up of 18months, there were no significant differences in KSS, KOOS or Böstman scores between the groups. CONCLUSION: No significant differences were identified when comparing the clinical outcomes of fixation of AO/OTA 34C1/2 fractures with suture tape or metallic cerclage fixation concerning re-operation rates, union rates, loss of fixation and functional outcome measures. These results cannot be extrapolated to more complex injury patterns or surgical techniques in which prominence of implanted material is more likely. LEVEL OF EVIDENCE: III.

Focal articular surface replacement as primary treatment for focal chondral defects of the femoral condyles: A series of 157 cases.

BACKGROUND: Focal chondral defects (FCDs) of the femoral condyle are common. Treatment has heretofore primarily consisted of non-surgical and biological treatments. Focal articular surface replacement (FASR) is an emerging technique utilizing small implants to essentially fill the FCD. Here we report functional outcome and re-operation rates following FASR as a primary treatment for FCDs of the femoral condyles. METHODS: Retrospective analysis of a prospectively collected database including 327 FASR procedures was performed to identify patients who underwent FASR of the femoral condyle with a modular cementless metallic implant (HemiCAPTM) as a primary procedure. Knee Injury and Osteoarthritis Outcome Score (KOOS), Oxford Knee Score (OKS), SF-36 Health Status Survey (SF-36) and Visual Analog Scale (VAS) were collected before and 6 weeks, 6 months, and 4 years after surgery. Implant revision and re-operation rate were recorded. RESULTS: 157 patients were included with a mean follow-up of 9.4 ± 1.3 years (range 7.0 to 11.4 years). The average age was 40.2 ± 5.3 years, 85% involved the medial condyle, and the average defect size was 3.6 ± 0.5 cm2. Primary FASR resulted in functional improvement on the KOOS (+52%), OKS (+69%) and SF-36 (+50%) scores and a reduction in VAS scores (-70%) at 4-year follow-up. Revision rate was 0.64% and the re-operation rate was 11%. CONCLUSION: This retrospective case-series supports primary FASR with HemiCAPTM implants as an alternative to biological procedures to treat medium-sized FCDs (2.5-4 cm2) of the femoral condyle, although long-term follow-up is necessary to determine if the clinical outcome and low revision rate can be maintained.

Surface Treatment and Bioinspired Coating for 3D-Printed Implants.

Three-dimensional (3D) printing technology has developed rapidly and demonstrates great potential in biomedical applications. Although 3D printing techniques have good control over the macrostructure of metallic implants, the surface properties have superior control over the tissue response. By focusing on the types of surface treatments, the osseointegration activity of the bone-implant interface is enhanced. Therefore, this review paper aims to discuss the surface functionalities of metallic implants regarding their physical structure, chemical composition, and biological reaction through surface treatment and bioactive coating. The perspective on the current challenges and future directions for development of surface treatment on 3D-printed implants is also presented.

Identification of skeletal remains by orthopaedic implant: A case report and brief review of the literature.

Establishing identity from skeletal remains is a challenging task for forensic experts. Identification in such cases can be achieved by dental records, post-mortem radiography and DNA profiling. However, these methods require additional data for comparisons. Positive identification can also be achieved using implanted medical devices. This is a rapid and inexpensive method, as long as a central database is maintained for effective tracking of such devices. We present a case report in which identity was established from skeletal remains using information furnished on the implanted metallic dynamic hip screw and side plate. This case report discusses the legal scenario in India and globally with regard to medical devices and their utility for forensic application. It emphasises the need for legal provision relating to medical devices in India, which would compel the manufacturer to use unique identification numbers for each medical device and to maintain a person-specific database.

Current interpretations on the in vivo response of bone to additively manufactured metallic porous scaffolds: A review.

Recent advances in the field of metallic additive manufacturing have expanded production capabilities for bone implants to include porous lattice structures. While traditional models of de novo bone formation can be applied to fully dense implant materials, their applicability to the interior of porous materials has not been well-characterized. Unlike other reviews that focus on materials and mechanical properties of lattice structures, this review compiles biological performance from in vivo studies in pre-clinical models only. First, we introduce the most common lattice geometry designs employed in vivo and discuss some of their fabrication advantages and limitations. Then lattice geometry is correlated to quantitative (histomorphometric) and qualitative (histological) assessments of osseointegration. We group studies according to two common implant variables: pore size and percent porosity, and explore the extent of osseointegration using common measures, including bone-implant contact (BIC), bone area (BA), bone volume/total volume (BV/TV) and biomechanical stability, for various animal models and implantation times. Based on this, trends related to in vivo bone formation on the interior of lattice structures are presented. Common challenges with lattice structures are highlighted, including nonuniformity of bone growth through the entirety of the lattice structure due to occlusion effects and avascularity. This review paper identifies a lack of systematic in vivo studies on porous AM implants to target optimum geometric design, including pore shape, size, and percent porosity in controlled animal models and critical-sized defects. Further work focusing on surface modification strategies and systematic geometric studies to homogenize in vivo bone growth through the scaffold interior are recommended to increase implant stability in the early stages of osseointegration.

Improvement of metallic artifacts in computed tomography in the absence of artifact reduction algorithms for spinal treatment planning applications.

AIM OF STUDY: The goal of this research was to investigate if application of optimized imaging parameters, recommended in literature, would be effective in producing the image quality required for treatment planning of spinal radiation fields with metallic implants. MATERIALS AND METHODS: CT images from an anthropomorphic torso phantom with and without spinal implants were acquired using different imaging protocols: raising kVp and mAs, reducing the pitch and applying an extended CT scale (ECTS) technique. Profiles of CT number (CT#) were produced using DICOM data of each image. The effect of artifact on dose calculation accuracy was investigated using the image data in the absence of implant as a reference and the recommended electron density tolerance levels (Δρe). RESULTS: Raising the kVp was the only method that produced improvement to some degree in CT# in artifact regions. Application of ECTS improved CT# values only for metal. CONCLUSIONS: Although raising the kVp was effective in reducing metallic artifact, the significance of this effect on Δρe values in corrected images depends on the required tolerance for treatment planning dose calculation accuracy. ECTS method was only successful in correcting the CT number range in the metal. Although, application of ECTS method did not have any effect on artifact regions, its use is necessary in order to improve delineation of metal and accuracy of attenuation calculations in metal, provided that the treatment planning system can use an extended CT# calibration curve. Also, for Monte Carlo calculations using patient's images, ECTS-post-processed-CT images improve dose calculation accuracy for impure metals.

Effects of focal metallic implants on opposing cartilage - an in-vitro study with an abrasion test machine.

BACKGROUND: For focal cartilage defects, biological repair might be ineffective in patients over 45 years. A focal metallic implant (FMI) (Hemi-CAP Arthrosurface Inc., Franklin, MA, USA) was designed to reduce symptoms. The aim of this study was to evaluate the effects of a FMI on the opposing tibial cartilage in a biomechanical set-up. It is hypothesized that a FMI would not damage the opposing cartilage under physiological loading conditions. METHODS: An abrasion machine was used to test the effects of cyclic loading on osteochondral plugs. The machine applied a compressive load of 33 N and sheared the samples 10 mm in the anteroposterior direction by 1 Hz. Tibial osteochondral plugs from porcine knees were placed in opposition to a FMI and cycled for 1 or 6 h. After testing each plug was fixed, stained and evaluated for cartilage damage. RESULTS: After 1 h of loading (n = 6), none of the osteochondral plugs showed histologic signs of degradation. After 6 h of loading (n = 6) three samples had histologic signs of injury in the tangential zone (grade 1) and one had signs of injury in the transitional and deep zones (grade 2). Exploration for 6 h resulted in significant more cartilage damage compared to the shorter exploration time (p = 0.06). However, no significant difference between saline and hyaluronic acid was evident (p = 0.55). CONCLUSION: Under physiologic loading conditions, contact with a FMI leads to cartilage damage in the opposing articular cartilage in six hours. In clinical practice, a thorough analysis of pre-existing defects on the opposing cartilage is recommended when FMI is considered.

Effects of a metallic implant on radiotherapy planning treatment-experience on a human cadaver.

BACKGROUND: Metallic implants (MIs) complicate radiotherapy planning. Several studies have worked on tissue-equivalent phantoms as experimental models to estimate dose distributions in this context. The application of these results to clinical practice remains disputable because the inhomogeneity of human tissue densities is a difficult factor to integrate into dose calculation software. In this work, we evaluate the impact of human tissue inhomogeneities by assessing the discrepancies between treatment planning system (TPS) dose calculations and measured delivered doses on a human cadaver with hip prostheses. METHODS: A total of 143 alanine dosimeters were positioned in contact with the prostheses (bones group), soft tissues (soft tissues group), skin surfaces (skin group) and natural cavities (cavities group) of a human cadaver. The planning target volume (PTV) corresponded to a standard endometrial cancer treatment. The irradiation was performed with 6 MV X-ray tomotherapy at the one fraction-dose of 10 Gy. RESULTS: A total of 140 dosimeters were analyzed. After applying a temperature correction coefficient to the measured doses, the global analysis of all dosimeters showed a significant difference between the calculated doses and the measured doses (P<0.001). For dosimeters of the bones, soft tissues, skin and cavities groups, this difference was also significant (P<0.001 for each group). The mean measured doses were 21.9% lower than the mean calculated doses in the global analysis and 17.0%, 21.2%, 33.0% and 19.0% lower for the bones, soft tissues, skin and cavities groups, respectively. CONCLUSIONS: This study showed that the received doses were significantly lower than the calculated doses and suggested the need to improve the understanding of this discrepancy.

Electrodeposition of Sr-substituted hydroxyapatite on low modulus beta-type Ti-45Nb and effect on in vitro Sr release and cell response.

Beta-type Ti-based alloys are promising new materials for bone implants owing to their excellent mechanical biofunctionality and biocompatibility. For treatment of fractures in case of systemic diseases like osteoporosis the generation of implant surfaces which actively support the problematic bone healing is a most important aspect. This work aimed at developing suitable approaches for electrodeposition of Sr-substituted hydroxyapatite (Srx-HAp) coatings onto Ti-45Nb. Potentiodynamic polarization measurements in electrolytes with 1.67 mmol/L Ca(NO3)2, which was substituted by 0, 10, 50 and 100% Sr(NO3)2, and 1 mmol/L NH4H2PO4 at 333 K revealed the basic reaction steps for OH- and PO43- formation needed for the chemical precipitation of Srx-HAp. Studies under potentiostatic control confirmed that partial or complete substitution of Ca2+- by Sr2+-ions in solution has a significant effect on the complex reaction process. High Sr2+-ion contents yield intermediate phases and a subsequent growth of more refined Srx-HAp coatings. Upon galvanostatic pulse-deposition higher reaction rates are controlled and in all electrolytes very fine needle-like crystalline coatings are obtained. With XRD the incorporation of Sr-species in the hexagonal HAp lattice is evidenced. Coatings formed in electrolytes with 10 and 50% Sr-nitrate were chemically analyzed with EDX mapping and GD-OES depth profiling. Only a fraction of the Sr-ions in solution is incorporated into the Srx-HAp coatings. Therein, the Sr-distribution is laterally homogeneous but non-homogeneous along the cross-section. Increasing Sr-content retards the coating thickness growth. Most promising coatings formed in the electrolyte with 10% Sr-nitrate were employed for Ca, P and Sr release analysis in Tris-Buffered Saline (150 mM NaCl, pH 7.6) at 310 K. At a sample surface: solution volume ratio of 1:200, after 24 h the amount of released Sr-ions was about 30-35% of that determined in the deposited Srx-HAp coating. In vitro studies with human bone marrow stromal cells (hBMSC) revealed that the released Sr-ions led to a significantly enhanced cell proliferation and osteogenic differentiation and that the Sr-HAp surface supported cell adhesion indicating its excellent cytocompatibility.

[Reverse meridional cyclodialysis ab interno with implantation of a metallic implant in patients with glaucoma of different etiology]. / Obratnyi meridional'nyi tsiklodializ ab interno s vvedeniem v supratsiliarnoe prostranstvo metallicheskogo implantata pri glaukome razlichnoi étiologii.

PURPOSE: To evaluate the safety and effectiveness of reverse meridional cyclodialysis (RMC) ab interno with implantation of a metallic implant into the supraciliary space for decreasing intraocular pressure in glaucoma patients. MATERIAL AND METHODS: RMC was performed ab interno in 51 patients, among which 30 patients had a metallic implant inserted into the supraciliary space (implant group). Twenty-one patients who underwent RMC ab interno without implant comprised the control group. The outcomes were evaluated after 12 months. RMC was performed through a clear corneal incision using a special spatula at 4-5 o'clock reaching 5-6 mm deep, width of the cleft was 11-12o of the iridocorneal angle. The evaluation criteria included adverse events, postoperative IOP changes, need for hypotensive medications and repeat surgery. The results were analyzed using variational statistics. RESULTS: Baseline mean IOP was 28.8±4.7 mmHg and 30.2±7.2 mmHg in implant and control groups, respectively, and at 12 months it decreased by 28.7±12.0% and 29.1±17.1%. Baseline mean medication usage was 2.7±0.8 and 2.6±0.9 in respective groups, at 12 months it decreased to 1.1±0.9 and 0.8±0.9. In the implant group, overall success was achieved in 93.3% of cases (complete success - 33.3%, partial success - 60.0%), while in the control group it was 66.7% (complete success - 28.6%, partial success - 38.1%) (p=0.03). In terms of IOP decrease, medication usage and adverse events the difference between the groups was statistically insignificant. Repeat surgery was required 5 times more frequently in the control group (33.3% vs 6.7%, p=3E-05). CONCLUSION: Implantation of a metallic implant into the supraciliary space to keep the cyclodialysis cleft open is safe and effective and substantially decreases the need for repeat surgery.

Biofunctionalization of metallic implants by calcium phosphate coatings.

Metallic materials have been extensively applied in clinical practice due to their unique mechanical properties and durability. Recent years have witnessed broad interests and advances on surface functionalization of metallic implants for high-performance biofunctions. Calcium phosphates (CaPs) are the major inorganic component of bone tissues, and thus owning inherent biocompatibility and osseointegration properties. As such, they have been widely used in clinical orthopedics and dentistry. The new emergence of surface functionalization on metallic implants with CaP coatings shows promise for a combination of mechanical properties from metals and various biofunctions from CaPs. This review provides a brief summary of state-of-art of surface biofunctionalization on implantable metals by CaP coatings. We first glance over different types of CaPs with their coating methods and in vitro and in vivo performances, and then give insight into the representative biofunctions, i.e. osteointegration, corrosion resistance and biodegradation control, and antibacterial property, provided by CaP coatings for metallic implant materials.

High comorbidity index is not associated with high morbidity and mortality when employing constrained arthroplasty as a primary treatment for intertrochanteric fractures in elderly patients.

AIM: The aim of our study is to investigate the results of constrained total hip arthroplasty as a primary treatment of intertrochanteric fractures (ITF) in elderly patients with high comorbidities. MATERIALS AND METHODS: Total hip replacement (THR) with a retentive cup was performed on 73 patients with ITF over the age of 54 years who had high comorbidities and a Charlson score above five. Short- and long-term complications were determined by follow-up. Bivariate analysis was conducted in order to determine the possible determinants of mortality and factors associated with comorbidity as measured by the Charlson comorbidities index. RESULTS: Patient demographics that consisted of females (58.9%) (p < 0.04) with the mean age of both males and females demonstrated no statistical significance. The mean hospitalization time and weight bearing time were 11 and 2.67 days, respectively. Only 4.1% needed re-intervention due to re-fracture and none due to prosthesis failure. There was a statistical significance between the comorbidity index and the mortality rate. However, no statistical significance was identified between the comorbidity index and the functional status after constrained THR. CONCLUSION: High comorbidity index is not associated with high morbidity and mortality when employing constrained arthroplasty as a primary treatment for ITF in elderly patients.