Durability Of Prosthesis Research Articles

Biomechanical Advances in Total Hip Arthroplasty: From Surgical Approach to Functional Recovery

This technical article discusses biomechanical advancements in total hip arthroplasty (THA), from surgical techniques to functional recovery. Focusing on the evolution of surgical approaches, it highlights the use of robotics and artificial intelligence to enhance implant positioning precision and minimize misalignments. Advanced materials, such as high-density polyethylene, and innovative prosthesis designs were also discussed, emphasizing their contribution to prosthesis durability and functionality. Additionally, perioperative management strategies, including modern analgesic blocks and nutritional support, have improved postoperative recovery, while structured rehabilitation protocols are essential for restoring gait and joint biomechanics. Finally, long-term considerations regarding prosthesis survival and patients' quality of life were explored, reinforcing the importance of a multidisciplinary approach and cutting-edge technologies.

Influence of heat-assisted vat photopolymerization on the physical and mechanical characteristics of dental 3D printing resins

The effects of heat-assisted vat photopolymerization (HVPP) on the physical and mechanical properties of 3D-printed dental resins, including the morphometric stability of 3D-printed crowns, were investigated. A resin tank was designed to maintain the resin at 30, 40, and 50 ℃ during the 3D printing process. Test specimens were fabricated using a commercial dental resin, with untreated resin serving as the control group. Key properties such as viscosity, curing kinetics, surface microhardness, flexural properties, and dimensional accuracy were evaluated. The viscosity of the resin decreased significantly (P < 0.05) with increasing temperature, thereby enhancing its flow properties. Photo-DSC analysis revealed a 17.58% increase in peak heat flow at 50 ℃, indicating accelerated polymerization. Surface microhardness improved significantly (P < 0.05) with HVPP, though a slight reduction was observed at 50 ℃ compared to that at 30 and 40 ℃. The flexural strength, modulus, and resilience were significantly enhanced (P < 0.05) at higher temperatures, with 50 ℃ yielding the best mechanical properties. However, 3D morphometric analysis showed increased root mean square deviation from the CAD design at elevated temperatures. Our results suggest that HVPP enhances the durability of dental prostheses, although careful optimization of the printing temperature is essential to balance their strength and accuracy.

Color Stability and Roughness of Ocular Prosthesis Between Heat‐Cured Acrylic and 3D Printed Acrylic After Artificial Weathering

Eye loss can majorly impact a person’s look, functionality, and psychological well‐being. This study addresses a critical gap in understanding the durability of ocular prostheses by investigated the surface roughness and color stability of ocular prostheses fabricated using three‐dimensional (3D) printing and heat‐cured polymethyl methacrylate (PMMA) acrylic resin (QC‐20 heat polymerize) after they were subjected to artificial weathering. Two techniques were used to create 100 samples (2 mm thickness and 20 mm diameter) that were fabricated and divided into 50 heat‐cured PMMA samples, and 50 samples were made using Next Dent Denture 3D acrylic resin printed with 3D printing technology stereolithography (SLA) 3D printer. All samples were subjected to 300 h of artificial weathering using a weathering chamber. Color changes were tested using a spectrophotometer, while surface roughness micrometers (µm) were measured with a profilometer. Descriptive statistics were used, followed by one‐way analysis of variance (ANOVA), independent sample t‐tests were used, and the significance level was α = 0.05. The results demonstrated a significant difference in color stability between the two materials and fabrication methods; the highest mean ΔE observed in heat‐cured PMMA samples was 2.67 (p = 0.003) and the lowest in 3D‐printed samples ΔE of 1.42, respectively. Regarding surface roughness, PMMA demonstrated the highest mean of 0.58 µm, while the lowest mean was with the 3D‐printed samples at 0.33 µm (p = 0.001), 3D‐printed prostheses exhibiting superior resistance to color changes after weathering. 3D‐printed prostheses maintained a significantly smoother surface texture compared to heat‐cured acrylic ones. These findings concluded that 3D‐printed ocular prostheses offer potential advantages in color stability and surface smoothness, potentially enhancing esthetic outcomes, wearability, and patient satisfaction.

Effect of Valve Type and Anesthesia Strategy for TAVR: 5-YearResultsoftheSOLVE-TAVITrial.

In the randomized SOLVE-TAVI (compariSon of secOnd-generation seLf-expandable vs. balloon-expandable Valves and gEneral vs. local anesthesia in Transcatheter Aortic Valve Implantation) trial comparing newer-generation self-expanding valves (SEV) and balloon-expandable valves (BEV), as well as conscious sedation (CS) and general anesthesia (GA), clinical outcomes were similar both for valve and anesthesia comparison at 30days and 1 year. Prosthesis durability may affect clinical outcomes during long-term follow-up. Moreover, the impact of the anesthesia strategy on long-term clinical outcomes is unknown so far. The authors sought to compare clinical outcomes during 5-year follow-up in the randomized SOLVE-TAVI trial. In the randomized, multicenter, 2× 2 factorial, open-label SOLVE-TAVI trial, 447 intermediate- to high-risk patients with severe, symptomatic aortic stenosis were randomly assigned to transfemoral transcatheter aortic valve replacement (TAVR) using either SEV (Evolut R, Medtronic) or BEV (SAPIEN 3, Edwards Lifesciences) and also to CS vs GA. Patients were followed-up for 5 years. During 5 years of follow-up, the combined predefined endpoint of all-cause mortality, stroke, moderate or severe paravalvular leakage, and permanent pacemaker implantation was similar in the SEV and BEV groups (67.7% vs 63.4%; HR: 0.89; 95%CI: 0.70-1.13; P=0.34). Stroke rates at 5 years were lower in the SEV group (2.2% vs 9.6%; HR: 4.84; 95%CI: 1.65-14.18; P=0.002). Regarding the anesthesia comparison, the primary endpoint of all-cause mortality, stroke, myocardial infarction, and acute kidney injury occurred in 51.4% in the CS group and 61.3% in the GA group (HR: 0.80; 95%CI: 0.62-1.04; P=0.09). All-cause mortality at 5 years was lower for CS (41.5% vs 54.3%; HR: 0.70; 95%CI: 0.53-0.94; P=0.02). Transfemoral TAVR using either SEV and BEV as well as CS and GA showed similar clinical outcomes at 5 years using a combined clinical endpoint.

Removable dental prostheses for patients with Sjögren's syndrome

Sjögren's syndrome (SS) is a chronic autoimmune condition primarily affecting the salivary and lacrimal glands, leading to pronounced dry mouth (xerostomia) and dry eyes. These symptoms create unique challenges for SS patients requiring removable dental prostheses, as the lack of saliva significantly impacts the retention, comfort, and overall effectiveness of these devices. Without adequate saliva, prosthetic retention diminishes, and patients frequently experience issues such as mucosal irritation and increased susceptibility to infections. To address these issues, tailored material choices are critical in designing effective prosthetic solutions. Soft liners, moisture-retentive acrylics, and antimicrobial coatings are among the innovations improving both retention and comfort for SS patients. The aesthetic and functional outcomes of prosthetic solutions are also essential considerations. Enhanced retention mechanisms, such as implant-supported overdentures, not only improve masticatory performance but also aid in preserving the patient’s facial profile and lip support. Advanced materials offering translucency and color stability contribute to a more natural appearance, which is critical for patient satisfaction. The maintenance of these prostheses requires specific care routines to mitigate microbial buildup and tissue irritation. Specialized cleaning agents and salivary substitutes help maintain hygiene and reduce discomfort, while regular follow-up visits enable timely adjustments to accommodate tissue changes and extend the prosthesis lifespan. Implementing a comprehensive approach that considers material selection, functional and aesthetic outcomes, and maintenance strategies can greatly enhance the quality of life for SS patients. By understanding and addressing the specific needs associated with xerostomic conditions, dental professionals can provide prosthetic solutions that offer both reliability and comfort in this challenging context. Regular patient education and diligent care routines remain essential to ensure the long-term success and durability of removable dental prostheses for individuals with SS.

Who Lives Longer, the Valve or the Patient? The Dilemma of TAVI Durability and How to Optimize Patient Outcomes

Over the past few years, transcatheter aortic valve implantation (TAVI) imposed itself as the first-choice therapy for symptomatic aortic stenosis (AS) in elderly patients at surgical risk. There have been continuous technological advancements in the latest iterations of TAVI devices and implantation techniques, which have bolstered their adoption. Moreover, the favorable outcomes coming out from clinical trials represent an indisputable point of strength for TAVI. As indications for transcatheter therapies now include a low surgical risk and younger individuals, new challenges are emerging. In this context, the matter of prosthesis durability is noteworthy. Initial evidence is beginning to emerge from the studies in the field, but they are still limited and compromised by multiple biases. Additionally, the physiopathological mechanisms behind the valve’s deterioration are nowadays somewhat clearer and classified. So, who outlasts who—the valve or the patient? This review aims to explore the available evidence surrounding this intriguing question, examining the various factors affecting prosthesis durability and discussing its potential implications for clinical management and current interventional practice.

Durability of porcine and pericardial prostheses in tricuspid valve replacement

ObjectiveBiologic valves dominate tricuspid valve replacement, yet data on different valve types are lacking. We compare the survival and durability of porcine and pericardial tricuspid prostheses. MethodsA retrospective review of consecutive patients undergoing tricuspid valve replacement with porcine (N = 542) or pericardial (N = 144) prostheses between 1975 and 2022 was performed using a prospectively maintained institutional database. Concurrent procedures were included. Cox proportional hazards and logistic regression were performed. ResultsPatients who received the porcine prosthesis, compared with pericardial, were younger (56 ± 17 years vs 63 ± 15 years) and more likely to present urgently (55% porcine, 44% pericardial); however, there were no differences in redo status or concomitant operations. Ten-year survival was not significantly different between the porcine and pericardial groups (35% ± 3% vs 28% ± 4%, respectively, P = .2). The 10-year cumulative incidence of structural valve deterioration (porcine 9% ± 2%, pericardial 11% ± 3%, P = .8), reoperation for structural valve deterioration (porcine 5% ± 1%, pericardial 4% ± 2%, P = .06), and severe regurgitation (porcine 4% ± 1%, pericardial 5% ± 2%, P = .7) were not significantly different between groups. The failure mode was similar, with no difference in severe stenosis (porcine 32/47 [68%], pericardial 11/16 [69%], P = .9) or severe regurgitation (porcine 18/47 [38%], pericardial 7/16 [44%], P = .7). On regression analysis, valve type was not associated with survival (P = .6). Valve type was not associated with structural valve deterioration (P = .1) or reoperation for structural valve deterioration (P = .9). ConclusionsIn our series, there were no differences in survival or durability between porcine and pericardial valves. In most patients undergoing tricuspid valve replacement, the choice of porcine versus pericardial prosthesis is unlikely to affect clinical outcomes.

Three-dimensional printing technology applied to the production of prosthesis: A systemic narrative review.

The purpose of this scoping review was to investigate the effects of 3-dimensional (3D)-printed prostheses. Articles published up to August 19, 2023, were searched in the PubMed, Cochrane Library, Embase, and Scopus databases. The search terms used were "3D printed prosthesis," "3D printed prostheses," "3D printed prosthe*," "3D printed artificial arm," "3D printed artificial leg," "3D printing prosthesis," "3D printing prostheses," "3D printing prosthe*," "3D printing artificial arm," and "3D printing artificial leg." This review included studies that applied 3D-printed prostheses to upper- or lower-limb amputees. Case reports, conference abstracts, presentations, reviews, and unidentified articles were excluded from the analysis. A total of 937 articles were identified, 11 of which were included after confirming eligibility through the title, abstract, and full text. The results indicated that the 3D-printed prostheses demonstrated the ability to substitute for the functions of impaired limbs, similar to conventional prostheses. Notably, the production cost and weight were reduced compared with those of conventional prostheses, increasing patient satisfaction. The use of 3D-printed prostheses is expected to gain prominence in future clinical practice. However, concerns regarding the durability of 3D-printed prostheses have increased among users. Therefore, there is an ongoing need to explore highly durable materials that can withstand the weight of the user without breaking easily. In addition, advancements are required in technologies that enable the depiction of various skin tones and the production of smaller-sized prostheses suitable for clothing.

Exploring the Impact of 3D Printing Technology on Patient-Specific Prosthodontic Rehabilitation: A Comparative Study

ABSTRACT Introduction: The rapid advancement of 3D printing technology has opened new avenues for patient-specific prosthodontic rehabilitation. This study aimed to explore the impact of 3D printing technology on prosthodontic outcomes and patient satisfaction through a comparative analysis. Materials and Methods: A total of 100 patients requiring prosthodontic rehabilitation were recruited for this study. The patients were randomly divided into two groups: the experimental group, where 3D printing technology was utilized for the fabrication of patient-specific prostheses, and the control group, where conventional fabrication techniques were employed. Various parameters were assessed, including prosthesis fit, occlusion, esthetics, and patient-reported outcomes such as comfort and satisfaction. Digital measurements and subjective evaluations were conducted to compare the outcomes between the two groups. Statistical analysis was performed using appropriate tests. Results: Preliminary findings indicated that the use of 3D printing technology in prosthodontic rehabilitation resulted in superior prosthesis fit, enhanced occlusal stability, and improved esthetics compared to conventional methods. Moreover, patients in the experimental group reported higher levels of comfort and overall satisfaction. The advantages of 3D printing technology were observed across different types of prosthodontic restorations, including crowns, bridges, and dentures. These results highlight the potential of 3D printing technology to revolutionize patient-specific prosthodontic rehabilitation. By facilitating precise fabrication, customization, and improved functional outcomes, 3D printing can enhance the overall quality of prosthodontic care. Further long-term studies are warranted to validate these findings and explore the cost-effectiveness and long-term durability of 3D-printed prostheses. Conclusion: In conclusion, this study demonstrates that the integration of 3D printing technology in patient-specific prosthodontic rehabilitation holds great promise for achieving optimal functional and esthetic outcomes. The findings contribute to advancing prosthodontic practices and provide valuable insights for clinicians and researchers seeking to incorporate this innovative technology into their treatment protocols.

In vitro investigation of the blood flow downstream of a 3D-printed aortic valve

The hemodynamics in the aorta as well as the durability of aortic valve prostheses vary greatly between different types of devices. Although placement and sizing of surgical aortic valve prostheses are excellent, the valve geometry of common devices cannot be customized to fit the patient’s anatomy perfectly. Similarly, transcatheter aortic valve implantation (TAVI) devices are not customizable and may be orientated unfavorably during implantation. Imperfect fit of an aortic valve prosthesis may result in suboptimal performance and in some cases the need for additional surgery. Leveraging the advent of precision, multi-material 3D-printing, a bioinspired silicone aortic valve was developed. The manufacturing technique makes it fully customizable and significantly cheaper to develop and produce than common prostheses. In this study, we assess the hemodynamic performance of such a 3D-printed aortic valve and compare it to two TAVI devices as well as to a severely stenosed valve. We investigate the blood flow distal to the valve in an anatomically accurate, compliant aorta model via three-dimensional particle tracking velocimetry measurements. Our results demonstrate that the 3D-printed aortic valve induces flow patterns and topology compatible with the TAVI valves and showing similarity to healthy aortic blood flow. Compared to the stenosis, the 3D-printed aortic valve reduces turbulent kinetic energy levels and irreversible energy losses by over 75%, reaching values compatible with healthy subjects and conventional TAVIs. Our study substantiates that the 3D-printed heart valve displays a hemodynamic performance similar to established devices and underscores its potential for driving innovation towards patient specific valve prostheses.

ANALYZING THE PERFORMANCE OF HIP CEMENT SPACERS: INVESTIGATION OF CRACK BEHAVIOR THROUGH A MULTISCALE APPROACH

Close collaboration between surgeons and engineers is paramount in the intricate process of designing and evaluating hip joint prostheses. In revision surgeries, cement spacers play a vital role, but their effectiveness hinges on the reinforcement of the cement, bone, and femur to minimize stress. To assess the fracture behavior of reinforced spacers, we employ a comprehensive three-dimensional approach that analyzes the three primary materials used for full stems: titanium, ceramics, and stainless steel. Our analysis focuses on evaluating the von Mises stress and stress intensity factor along the crack tip using linear elastic analysis. Additionally, we utilize the extended finite element Method (X-FEM) to simulate crack initiation and propagation in non-reinforced cement spacers. By comparing the results obtained from these two methods, we gain valuable insights into the influence of different materials on the performance and durability of reinforced spacers. Our findings unequivocally demonstrate that reinforcing spacers with ceramic and stainless-steel full stems are exceptionally effective techniques for enhancing the strength of hip spacers. Specifically, we observed a significant reduction of stress levels by 30&amp;#37; in various hip prosthesis components, along with a notable 23&amp;#37; decrease in the stress intensity factor for spacers reinforced with ceramic stems. These insights are invaluable for spacer designers and can contribute significantly to improving the durability of hip joint prostheses, ultimately minimizing the need for early hip revisions.

Bacterial cellulose as a promising material for pulmonary valve prostheses: In vivo study in a sheep model.

Currently, no consensus exists regarding the most durable prosthesis for pulmonary valve replacement. Bacterial cellulose is a resistant, nonbiodegradable, nonpyrogenic bioimplant with low hemolysis and clotting properties. We hypothesized that bacterial cellulose heart valve prostheses could be an attractive alternative for pulmonary valve replacement. We conducted a large animal model experiment in three adult sheep. The animals underwent open-heart surgery and cardiopulmonary bypass for bacterial cellulose conduit implantation in the pulmonary position. The sheep were followed for seven months, and clinical and laboratory parameters were analyzed. Echocardiographic evaluations were performed at 3 and 7 months. After seven months, the sheep were sacrificed and an autopsy was performed. The explanted conduits were radiologically and histopathologically analyzed. All sheep survived the operation, showing good recovery and normal health status; no adverse events were noted during the 7-month postoperative follow-up. Interval laboratory findings were normal with no signs of hemolysis or infection. Echocardiographic analysis after 7 months revealed a normal mean pressure gradient with excellent cusp motion and coaptation; a trace of regurgitation was found in two sheep. X-ray analysis of the explanted conduits revealed no structural defects in the leaflets with minimal calcification. Histological examination showed slight thickening of the conduit by pannus formation. No material failure, no calcification inside the material, and only minor calcification extrinsic to the matrix were observed. This pilot study provides evidence that bacterial cellulose may be suitable for pulmonary valve prostheses and surgical pulmonary artery plasty. Further studies on the high pressure side of the left heart are needed.

Advances in the treatment of temporomandibular joint disorders

The management of temporomandibular joint (TMJ) dysfunctions has evolved significantly in recent decades with the development of minimally invasive surgical techniques and customised prostheses. Arthrocentesis and arthroscopy stood out for their efficacy in the treatment of mild and moderate pathologies. Arthrocentesis, described by Nitzan, allowed inflammatory products to be removed and the joint disc to be released in a quick and minimally invasive procedure, improving mobility and reducing pain. Arthroscopy offered direct visualisation of the joint, facilitating the diagnosis and treatment of more complex cases. Advanced procedures, such as the triangulation technique, extended its usefulness in the management of disc dislocations and adhesions. In severe cases, such as ankylosis or structural deformities, customised prostheses became the best option. These prostheses, designed with CAD/CAM technology, guaranteed a precise anatomical fit and significant functional improvement. However, their implementation was limited to patients where minimally invasive options were insufficient due to their surgical complexity and associated costs. Advances in biocompatible materials, such as titanium alloys and PEEK, improved the durability and osseointegration of prostheses, optimising long-term outcomes. This technological and medical progress allowed for a more tailored and effective approach to treating TMJ dysfunctions, improving patients' quality of life and reducing complications. Appropriate treatment selection according to severity and individual characteristics was key to therapeutic success.

Shear Strength of Repaired 3D-Printed and Milled Provisional Materials Using Different Resin Materials with and without Chemical and Mechanical Surface Treatment.

The aim of this study was to assess the shear bond strength of 3D-printed and milled provisional restorations using various resin materials and surface finishes. There were 160 preliminary samples in all, and they were split into two groups: the milled group and the 3D-printed group. Based on the resin used for repair (composite or polymethylmethacrylate (PMMA)) and the type of surface treatment utilized (chemical or mechanical), each group was further divided into subgroups. The specimens were subjected to thermocycling from 5 °C to 55 °C for up to 5000 thermal cycles with a dwell time of 30 s. The mechanical qualities of the repaired material underwent testing for shear bond strength (SBS). To identify the significant differences between the groups and subgroups, a statistical analysis was carried out. Three-way ANOVA was used to analyze the effects of each independent component (the material and the bonding condition), as well as the interaction between the independent factors on shear bond strength. Tukey multiple post-hoc tests were used to compare the mean results for each material under various bonding circumstances. The shear bond strengths of the various groups and subgroups differed significantly (p < 0.05). When compared to the milled group, the 3D-printed group had a much greater mean shear bond strength. When compared to PMMA repair, the composite resin material showed a noticeably greater shear bond strength. In terms of surface treatments, the samples with mechanical and chemical surface treatments had stronger shear bonds than those that had not received any. The results of this study demonstrate the effect of the fabrication method, resin type, and surface treatment on the shear bond strength of restored provisional restorations. Particularly when made using composite material and given surface treatments, 3D-printed provisional restorations showed exceptional mechanical qualities. These results can help dentists choose the best fabrication methods, resin materials, and surface treatments through which to increase the durability and bond strength of temporary prosthesis.

Revision total hip prosthesis with a primary prosthesis without bone graft

The durability of total hip prostheses and changes in surgical approaches for femoral neck fractures is a crucial issue in the medical literature. Worldwide, it has been observed that the longevity of total hip prostheses ranges from 10 to 30 years, according to several studies. This phenomenon could be due to several factors, such as differences in population demographics, variations in standards of care, or even particularities in the health and lifestyle of local patients. A 56-year-old male patient, with a history of electrocution in 2000 in which he suffered a transcervical fracture of the left hip with traumatic amputation of the right forearm; a total left hip arthroplasty with polyethylene metal head 28 was performed. It is concluded that, the clinical case highlights the need for individualized care and an adaptive approach in the management of total hip replacements, underlining that a careful approach and execution of preoperative, intraoperative and postoperative plans can lead to satisfactory and durable results, even in rare situations.

Analysis of durability and replacement of vocal prostheses in total laryngectomy patients at a head and neck surgery referral center.

The use of tracheoesophageal prostheses has become the gold standard in vocal rehabilitation of patients undergoing total laryngectomy. However, this method also has limitations, such as the need for frequent replacement of prostheses due to leakage or other complications. We have designed a study to access the clinical profile of patients using tracheoesophageal prostheses as vocal rehabilitation after total laryngectomy and to determine the average rate of changes, as well as the main causes of prostheses replacement. A retrospective cohort study was performed based on patients who underwent rehabilitation with voice prostheses after total laryngectomy between 2008 and 2017. The sample consisted of 93 patients and 432 vocal prostheses replacement events. The median change of prostheses per patient was 210.25days, (range 57.33 to 651.50). The most frequent cause of prostheses replacement was leakage through the prostheses, 218 (50.46%). Lower level of education was associated to higher prostheses replacement rate. The results of this study show that the median of prostheses durability is higher than that presented in the literature, the main cause of replacement was protheses leakage and that low educational level is associated to higher replacement rate.

Long-term outcomes of aortic valve replacement in dialysis patients - a nationwide retrospective cohort study.

Improved durability of modern biologic prostheses and growing experience with the transcatheter valve-in-valve technique have contributed to a substantial increase in the use of bioprostheses in younger patients. However, discussion of prosthetic valve selection in dialysis patients remains scarce as the guidelines are updated. This study aims to compare long-term outcomes between propensity score-matched cohorts of dialysis patients who underwent primary aortic valve replacement with a mechanical prosthesis or a bioprosthesis. Longitudinal data of dialysis patients who underwent primary aortic valve replacement between 1 January 2001 and 31 December 2018, were retrieved from the National Health Insurance Research Database. A total of 891 eligible patients were identified, of whom 243 ideally matched pairs of patients were analyzed. There was no significant difference in all-cause mortality (hazard ratio 1.11, 95% CI: 0.88-1.40) or the incidence of major adverse prosthesis-related events between the two groups (hazard ratio 1.03, 95% CI: 0.84-1.25). In patients younger than 50 years of age, using a mechanical prosthesis was associated with a significantly longer survival time across 10 years of follow-up than using a bioprosthesis (restricted mean survival time) at 10 years: 7.24 (95% CI: 6.33-8.14) years for mechanical prosthesis versus 5.25 (95% CI: 4.25-6.25) years for bioprosthesis, restricted mean survival time difference 1.99 years, 95% CI: -3.34 to -0.64). A 2-year survival gain in favor of mechanical prostheses was identified in dialysis patients younger than 50 years. The authors suggest mechanical prostheses for aortic valve replacement in these younger patients.

Is the Acetabular Cup Orientation Different in Robot-Assisted and Conventional Total Hip Arthroplasty With Right-Handed Surgeons Using an Anterolateral Approach?

Introduction Total hip arthroplasty (THA) is one of the most successful orthopaedic procedures. Survival rates from 90% at 10 years to 93% at 20 years have been reported in different studies. Differences in implant and patient characteristics can undoubtedly explain some of this variability observed in prosthesis durability, but the effect of surgical technique and implant orientation cannot be ignored. Therefore, many intraoperative methods (anatomic landmarks, intraoperative x-ray, fluoroscopy, navigation, and robotic surgery) have been attempted to avoid acetabular component malpositioning.Although postoperative computed tomography (CT) is accepted as the gold standard for the measurement of acetabular anteversion, it remains controversial in respect of costs and radiation exposure. The aim of this study was to examine how acetabular component orientation was affected in robotic and conventional THA operations performed by two surgeons with right-hand dominance. Material and methods The study included 113 primary THA operations performed on 113 patients between 2017 and 2022 in two groups: (i) robotic THA (Mako, Stryker Corporation, Kalamazoo, Michigan, United States) (55 patients) and (ii) conventional THA (58 patients). The patients comprised 51 males and 62 females. THA was performed on 54 right-side hips and 59 left-side hips. The operations were performed by two orthopaedic surgeons, each with 20 years of arthroplasty experience, on all the patients in the lateral decubitus position with an anterolateral approach. In all the cases, the orientation of the acetabular component was 40° inclination and 20° anteversion. Difficult THA procedures (patients with developmental dysplasia of the hip (DDH), a history of hip surgery, revision THA, defect or deformity of the acetabulum, a history of scoliosis or lumbar posterior surgery, or those requiring proximal femoral osteotomy) were excluded from the study. Using the Liaw and Lewinnek methods, the acetabular component anteversion was measured on the radiographs taken in the optimal position postoperatively and the acetabular cup inclination angles were measured on the pelvis radiographs. The groups were compared using the Kolmogorov-Smirnov, Pearson Chi-square and Mann-Whitney U statistical tests. The limits were accepted as 40±5° for inclination and 20±5° for anteversion. Results No statistically significant difference was determined between the groups in respect of age, gender, or operated side. No statistically significant difference was determined between the optimal acetabular cup inclination angles of the robotic and conventional THA groups (p = 0.79). No statistically significant difference was determined between the optimal acetabular cup anteversion angles of the left and right conventional THA groups. Statistically significantly better results were determined in the robotic group in respect of acetabular cup anteversion (p<0,001). Conclusion The optimal orientation of the acetabular component is a key factor for successful THA. Otherwise, revision surgery is inevitable for reasons such as instability, impingement, or increased wear. The results of this study demonstrated that robotic surgery was superior to the conventional method in the placement of the acetabular component in the desired orientation.

Giant pseudoaneurysm due to Dacron graft degeneration: A case report

Knitted Dacron grafts are often preferred as they are easy to process, soft, and flexible; they also tend to expand due to their high porosity. Bleeding and pseudoaneurysm formation at the anastomotic site are common complications of vascular surgery, but nonanastomotic bleeding due to degeneration of Dacron graft's textile structure is rare. Here, we present a 70-year-old male diagnosed with a giant pseudoaneurysm that continues from the femoral artery to the popliteal artery formed due to the degeneration of the previous seven-year-old prosthetic graft. The pseudoaneurysm continued to be the source of arterial flow with its capsule, and the arterial flow into it was able to provide blood supply to the lower extremity without causing ischemia. The patient underwent surgery to excise the giant pseudoaneurysm and create a new bypass between the femoral and popliteal arteries. Today, the durability of prostheses is becoming increasingly important, and modifications in the manufacturing process have made Dacron grafts more resistant to cyclic pulsatile stretching and facilitated the adaptation of the prosthetic material to the host tissue. Despite all the remarkable innovations over the last 50 years, complications of prosthetic grafts can result in fatal bleeding. This situation emphasizes the importance of close follow-up and detailed clinical and radiological evaluation of patients.

A feasibility study of promoting osseointegration surface roughness by micro-milling of Ti-6Al-4V biomedical alloy

The reliability of a prosthetic implant needs durability, biocompatibility, and osseointegration capability. Accomplishing these characteristics, Ti-6Al-4V alloy is the main used material for implant fabrication. Moreover, it can be processed by additive manufacturing technique, permitting to meet the needs of patience-tailored, often complex shaped, prosthesis topologies. Once an implant is realized, it is finished by machining operations and its osseointegration capability is heavily influenced by the resulting surface roughness. Consequently, the assessment of this latter is mandatory to evaluate the prosthesis durability. This paper presents the analysis of surface roughness of Ti-6Al-4V micro-milled specimens produced by plastic deformation, selective laser melting, and electron beam melting processes. A central composite design was employed for planning the cutting tests. The comparison between surface roughness results and its values for enhancing osseointegration, firstly permitted to individuate the range of micro-milling suitable applications, which have been individuated as ball joints, bone plates, and screws. Next, the statistical analysis of the experimental measurements allowed the identification of the most influential micro-milling parameters together with the determination of the mathematical models of surface roughness by response surface methodology. The good comparison among calculated and experimental results revealed the reliability of the model, allowing the prediction of achievable surface roughness once micro-machining parameters are selected, or their optimization as a function of a desired surface roughness value.