Search

ObjectiveTo evaluate the kinematics and stability of the temporomandibular joint (TMJ) of cats and dogs with and without a TMJ replacement (TMJR) prosthesis under simulated bite forces and mouth opening.AnimalsSixteen cadaver skulls from domestic cats (n = 8) and medium- to large-breed dogs (n = 8).MethodsIntact TMJs were tested. Following condylectomy and coronoidectomy, the skulls were fitted with a TMJR prosthesis unilaterally and retested. Prosthesis was similarly implanted in the contralateral TMJ in 4 cats and 4 dogs before retesting. Left and right bite motions were evaluated before bite contact to peak bite force (200 N in dogs, 63 N in cats). Mouth opening motion was recorded. Mandibular displacement under load was evaluated in 3 orthogonal planes. Maximal displacement was compared between TMJR groups and native TMJ. Prosthesis-bone motion of the temporal and mandibular components was evaluated during simulated bites and mouth opening.ResultsTMJR resulted in joint motion not demonstrably different from the native TMJ, with the ability to fully open and close the mouth and with minimal laterotrusion. The TMJR prosthesis demonstrated similar stability after unilateral and bilateral replacement during bite force and with an open mouth. Mean implant-bone motion during bite simulations for the temporal and mandibular TMJR components was ≤ 60 µm in cats and ≤ 30 µm in dogs.Clinical relevanceA novel TMJR can be implanted and allows normal jaw motion. Joint stability is maintained after TMJR implantation in the TMJ of dogs and cats TMJ that is devoid of muscular support.

The article provides readers with a detailed overview of the AutoMedPrint technology, its advantages and opportunities, based on a number of studies and case examples. The AutoMedPrint system represents a significant advancement in the field of orthopedics, offering a comprehensive solution for the automated design and rapid production of personalized orthopedic and prosthetic devices through 3D printing technology. This paper details the system’s capabilities and methodologies behind it, which include the design and manufacturing of various devices such as wrist hand orthoses (WHO) and ankle foot orthoses (AFO), among others. These devices are crafted using data obtained from precise anthropometric measurements, allowing for high customization to meet individual patient needs. The AutoMedPrint system enhances the quality of life for patients by providing devices that are not only functional and cost-effective but also rapidly produced, ensuring timely intervention. Case studies demonstrate the system’s effectiveness in practical scenarios, highlighting its potential to revolutionize orthopedic care by integrating new materials and technologies that adapt to changing medical and patient requirements. The discussion extends to the lifecycle of the produced devices, emphasizing sustainability and continuous improvement, ensuring the system’s relevance and efficacy in modern medical practice. [ABSTRACT FROM AUTHOR]

Wrist function is a top priority for transradial amputees. However, the combined functional, biomechanical, and cognitive impact of using a powered prosthetic wrist is unclear. Here, we quantify task performance, compensatory movements, and cognitive load while three transradial amputees performed a modified Clothespin Relocation Task using two myoelectric prostheses with and without the wrists. The two myoelectric prostheses include a commercial prosthesis with a built-in powered wrist, and a newly developed inexpensive prosthetic wrist for research purposes, called the "Utah wrist", that can be adapted to work with various sockets and prostheses. For these three participants, task failure rate decreased significantly from 66% ± 12% without the wrist to 39% ± 9% with the Utah wrist. Compensatory forward leaning movements also decreased significantly, from 24.2° ± 2.5 without the wrist to 12.6° ± 1.0 with the Utah wrist, and from 23.6° ± 7.6 to 15.3° ± 7.2 with the commercial prosthesis with an integrated wrist. Compensatory leftward bending movements also significantly decreased, from 20.8° ± 8.6 to 12.3° ± 5.3, for the commercial with an integrated wrist. Importantly, simultaneous myoelectric control of either prosthetic wrist had no significant impact on cognitive load, as assessed by the NASA Task Load Index survey and a secondary detection response task. This work suggests that functional prosthetic wrists can improve dexterity and reduce compensation without significantly increasing cognitive effort. These results, and the introduction of a new inexpensive prosthetic wrist for research purposes, can aid future research and development and guide the prescription of upper-limb prostheses. [ABSTRACT FROM AUTHOR]

In this study, we present a method for estimating the viscoelasticity of a leaf-spring sports prosthesis using advanced energy minimizing inverse kinematics based on the Piece-wise Constant Strain (PCS) model to reconstruct the three-dimensional dynamic behavior. Dynamic motion analysis of the athlete and prosthesis is important to clarify the effect of prosthesis characteristics on foot function. However, three-dimensional deformation calculations of the prosthesis and viscoelasticity have rarely been investigated. In this letter, we apply the PCS model to a prosthesis deformation, which can calculate flexible deformation with low computational cost and handle kinematics and dynamics. In addition, we propose an inverse kinematics calculation method that is consistent with the material properties of the prosthesis by considering the minimization of elastic energy. Furthermore, we propose a method to estimate the viscoelasticity by solving a quadratic programming based on the measured motion capture data. The calculated strains are more reasonable than the results obtained by conventional inverse kinematics calculation. From the result of the viscoelasticity estimation, we simulate the prosthetic motion by forward dynamics calculation and confirm that this result corresponds to the measured motion. These results indicate that our approach adequately models the dynamic phenomena, including the viscoelasticity of the prosthesis. [ABSTRACT FROM AUTHOR]

Revision total hip arthroplasty (rTHA) involving acetabular defects is a complex procedure associated with lower rates of success than primary THA. Computational modeling has played a key role in surgical planning and prediction of postoperative outcomes following primary THA, but modeling applications in rTHA for acetabular defects remain poorly understood. This study aimed to systematically review the use of computational modeling in acetabular defect classification, implant selection and placement, implant design, and postoperative joint functional performance evaluation following rTHA involving acetabular defects. The databases of Web of Science, Scopus, Medline, Embase, Global Health and Central were searched. Fifty‐three relevant articles met the inclusion criteria, and their quality were evaluated using a modified Downs and Black evaluation criteria framework. Manual image segmentation from computed tomography scans, which is time consuming, remains the primary method used to generate 3D models of hip bone; however, statistical shape models, once developed, can be used to estimate pre‐defect anatomy rapidly. Finite element modeling, which has been used to estimate bone stresses and strains, and implant micromotion postoperatively, has played a key role in custom and off‐the‐shelf implant design, mitigation of stress shielding, and prediction of bone remodeling and implant stability. However, model validation is challenging and requires rigorous evaluation and comparison with respect to mid‐ to long‐term clinical outcomes. Development of fast, accurate methods to model acetabular defects, including statistical shape models and artificial neural networks, may ultimately improve uptake of and expand applications in modeling and simulation of rTHA for the research setting and clinic. [ABSTRACT FROM AUTHOR]

This study introduces an innovative design for a Variable Stiffness 3 Degrees of Freedom actuated wrist capable of actively and continuously adjusting its overall stiffness by modulating the active length of non-linear elastic elements. This modulation is akin to human muscular cocontraction and is achieved using only four motors. The mechanical configuration employed results in a compact and lightweight device with anthropomorphic characteristics, making it potentially suitable for applications such as prosthetics and humanoid robotics. This design aims to enhance performance in dynamic tasks, improve task adaptability, and ensure safety during interactions with both people and objects. The paper details the first hardware implementation of the proposed design, providing insights into the theoretical model, mechanical and electronic components, as well as the control architecture. System performance is assessed using a motion capture system. The results demonstrate that the prototype offers a broad range of motion ([55, −45]° for flexion/extension, ±48° for radial/ulnar deviation, and ±180° for pronation/supination) while having the capability to triple its stiffness. Furthermore, following proper calibration, the wrist posture can be reconstructed through multivariate linear regression using rotational encoders and the forward kinematic model. This reconstruction achieves an average Root Mean Square Error of 6.6°, with an R2 value of 0.93. [ABSTRACT FROM AUTHOR]

Objective: Multi‐segmental total en bloc spondylectomy (TES) gradually became more commonly used by clinicians. However, the choice of surgical strategy is unclear. This study aims to investigate the biomechanical performance of different prosthesis types and fixation ranges in multisegmental TES. Methods: In this study, a validated finite element model of T12–L2 post‐spondylectomy operations were carried out. The prostheses of these models used either 3D‐printed artificial vertebrae or titanium mesh cages. The fixed range was two or three segment levels. Range of motion, stress distribution of the endplate and internal fixation system, intervertebral disc pressure, and facet joint surface force of four postoperative models and intact model in flexion and extension, as well as lateral bending and rotation were analyzed and compared. Results: The type of prosthesis used in the anterior column reconstruction mainly affected the stress of the adjacent endplate and the prosthesis itself. The posterior fixation range had a greater influence on the overall range of motion (ROM), the ROM of the adjacent segment, the stress of the screw‐rod system, and adjacent facet joint surface force. For the model of the same prosthesis, the increase of fixed length resulted in an obvious reduction of ROM. The maximal decrease was 70.23% during extension, and the minimal decrease was 30.19% during rotation. Conclusion: In three‐segment TES, the surgical strategy of using 3D‐printed artificial prosthesis for anterior column support and pedicle screws for posterior fixation at both two upper and lower levels respectively can reduce the stress on internal fixation system, endplates, and adjacent intervertebral discs, resulting in a reduced risk of internal fixation failure, and ASD development. [ABSTRACT FROM AUTHOR]

Background: This retrospective study compares the outcomes of trapeziectomy and Weilby suspensionplasty procedure versus implant arthroplasty using the TOUCH® prosthesis for basilar thumb arthritis in an Asian population. Methods: A total of 15 consecutive thumbs in 13 patients were included in this study. Six patients (2 male, 4 female, mean age of 62 years old) underwent trapeziectomy and Weilby suspensionplasty procedure. Seven patients (4 male, 3 female, mean age 63 years old) underwent implant CMCJ arthroplasty using the TOUCH® prosthesis. Data collected include demographics, severity of arthritis on plain radiographs of the thumb basilar joint, length of follow-up, pre- and postoperative pain levels, Kapandji thumb opposition score, grip and pinch strength and the time taken to return to work. Results: Patients in the trapeziectomy and Weilby suspensionplasty group had a mean follow-up of 4.5 months, while those in the TOUCH® implant arthroplasty group had a mean follow-up of 14 months. TOUCH® implant arthroplasty patients showed significantly higher grip strengths at 3 months post-surgery and a shorter return to work. There were no differences in pinch strength at 3 months, pinch or grip strength at 6 months or pain scores. Complications included prolonged scar hypersensitivity in two patients who underwent the Weilby suspensionplasty and a dislocated TOUCH® implant cup in one patient. Conclusions: Our study suggests that in the short term, CMCJ implant arthroplasty with the TOUCH® prosthesis produces results comparable to trapeziectomy and Weilby suspensionplasty. Level of Evidence: Level III (Therapeutic) [ABSTRACT FROM AUTHOR]

Background: Treatment options for correcting limb-length discrepancy after limb-salvage reconstruction for proximal tibial osteosarcoma in children have several limitations. Therefore, we aimed to evaluate the feasibility, complications, prognosis, and clinical outcomes of reconstruction using hemiarthroplasty after tumor resection in pediatric patients with proximal tibial osteosarcoma. Methods: We conducted a comprehensive retrospective analysis of the data of pediatric patients with osteosarcoma of the proximal tibia who underwent surgery between December 2008 and November 2018 at our center. We enrolled 49 consecutive patients who underwent hemiarthroplasty. The cruciate ligaments of all patients were reconstructed using special spacers, and the medial and lateral collateral ligaments of the knee and joint capsule were reconstructed using a mesh. Postoperatively, if the unequal length of both lower limbs exceeded 4 cm or knee instability occurred, a second-stage surgery was performed for limb lengthening and replacing the distal femoral prosthesis. We analyzed the oncological prognosis, complications of hemiarthroplasty, postoperative stability, and postoperative function. Results: The follow-up period ranged between 11 and 159 months, with a median of 84 (62, 129) months. The overall 5-year survival rate was 83.2%. Thirty-nine patients survived at the end of the follow-up period with 34 prostheses (87.2%). The overall prosthesis survival rate was 87.4% after 5 years, indicating the long-term benefits of the procedure. Limb length was measured in 28 adult patients. The average limb-length discrepancy was 33 ± 15 mm with a median of 33 mm (21, 47); the femur and tibia caused a discrepancy of 8.5 ± 9.9 mm and 24.8 ± 15.5 mm, respectively. The patients had 30–135° of knee motion, with a mean of 82 ± 24°. The femoral tibial angle was greater on the affected side than on the healthy side, with a mean difference of 4.5°±3.6°. The Musculoskeletal Tumor Society (MSTS) score was 25 ± 3. Five patients underwent second-stage distal femoral prosthesis replacement, with mean MSTS scores of 24 ± 2 and 28 ± 1 before and after second-stage surgery, respectively. Conclusions: Hemiarthroplasty in children reduces limb-length discrepancy in adulthood by rebuilding cruciate ligaments, lateral collateral ligaments, and the joint capsule, thereby improving knee stability. [ABSTRACT FROM AUTHOR]

Purpose: Total Elbow Arthroplasty (TEA) was first developed to treat severe rheumatoid arthritis, but its uses have grown to encompass end-stage osteoarthritis, post-traumatic arthritis, and distal humeral fractures. This study analyzes indications changes, long-term survival, complications, and post-operative functional results of the Coonrad-Morrey prostheses, enhancing the existing literature on this technique and substantial case history. Methods: We included 122 arthroplasties in 117 patients, 28 males and 89 females (mean age of 67 years) treated in our hospital between 2002 and 2016. Minimum follow-up was four years. We collect functional parameters of 48 patients (51 elbows), due to death of patients due to old age and loss at follow-up. Results: Survival rate at five years was 90%, 85% at 10 years and 83% at 15 years. The overall medium Mayo elbow score was 79.7 ± 18.3 with the highest result in osteoarthritis patients (p < 0.005); QuickDASH score was 33.1 ± 25.5 with the worse result in rheumatoid group. Average post-operative arc of motion (ROM) was 95°±27°. There were complications in 46 out of 122 cases (37.7%) and revision surgeries were performed in 12 of them (9.8%): seven aseptic loosening, four late septic loosening, one bushing wear. In 27 instances (22.1%) was reported ulnar nerve involvement. Conclusion: Coonrad-Morrey prosthesis has shown satisfactory clinical results in the treatment of a wide range of pathologies. The long-term implant survivorship was satisfactory, yet the occurrence of failures and complications cannot be overlooked, above all the ulnar nerve paresthesia. There was a good recovery in quality of life, pain-free with limited residual limb disability. [ABSTRACT FROM AUTHOR]

Introduction: Patients with severe aortic stenosis referred for transcatheter aortic valve implantation (TAVI) often present with concomitant coronary artery disease (CAD). The management of CAD in these patients remains a topic of debate, encompassing the evaluation and timing of percutaneous coronary intervention (PCI). Areas Covered: This review article aims to offer an overview of the role of coronary revascularization in TAVI patients, highlighting the advantages and disadvantages of different strategies: PCI before, concomitant with, and after TAVI. Considering that TAVI indications are expanding and patients with low surgical risk are now being referred for TAVI, the rate of PCI among patients undergoing TAVI is expected to increase. Historically, PCI was performed before TAVI. However, there is now a growing trend to defer PCI until after TAVI. Expert opinion: It is plausible that in the future, there will be an increase in PCI after TAVI due to several factors: first, multiple studies have shown the safety of TAVI even in patients with severe untreated CAD; second, improvements in TAVI device implantation techniques, such as commissural alignment and patient-specific device selection, have improved access to the coronary arteries post-TAVI. [ABSTRACT FROM AUTHOR]

Background: Self-adhesive resin cements (SARCs) are widely used for fixed prostheses, but incomplete cleaning near the gingival margin can cause inflammation. However, the factors influencing cement properties and the biological response of gingival fibroblasts to cement eluates are not well understood. This study examines the impact of two light-polymerizing units (LPUs) on the physical and chemical properties of two SARCs under simulated clinical conditions, as well as the subsequent response of human gingival fibroblasts (hGFs) to these eluates. Methods: Dental cement discs of SARCs were polymerized using Kerr DemiPlus and 3 M Elipar DeepCure-S LED LPUs with or without a 2-mm thick zirconia screen. Physical properties (microhardness, surface roughness, residual monomers) were evaluated. hGFs' cell viability, wound healing potency, and gene expression were assessed. Results: Both Maxcem and RelyX exhibited reduced microhardness and increased surface roughness when polymerized through zirconia or with DemiPlus LPU. Higher residual monomers (HEMA and GDMA in Maxcem; TEGDMA in RelyX) concentration was observed with DemiPlus and zirconia polymerization. Maxcem polymerized with DemiPlus exhibited lower cell viability, impaired healing, and altered gene expression in hGFs compared to those polymerized with Elipar LPU. Gene expression changes included downregulated NRF2 and HO-1 and upregulated CCR-3. Conclusions: Light-polymerizing Maxcem through zirconia with DemiPlus LPU compromised SARCs' properties, leading to higher residual monomers and negatively impacting hGFs' viability, healing, and gene expression. Careful material selection and polymerization techniques are crucial to minimize adverse effects on surrounding tissues. Clinical significance: Clinicians should exercise caution when using LPUs and SARCs, especially when polymerizing through zirconia. This will help optimize the physical and chemical properties of SARCs and minimize potential adverse effects on the surrounding gingival soft tissues. [ABSTRACT FROM AUTHOR]

Background: Insufficient tuberosity healing is the most common reason for poor outcome after treatment of proximal humerus fractures (PHFs) using hemiarthroplasty (HA). In these cases, revision to reverse total shoulder arthroplasty (RTSA) can improve function and reduce pain in the short term, however, long-term results remain scarce. Aim of this study was to evaluate the clinical and radiological mid- to long-term results in patients with a revision RTSA after failed HA for PHF. Methods: In this retrospective study all patients that received a revision to RTSA after failed fracture HA between 2006 and 2018 were included. A total of 49 shoulders in 48 patients (38 female, 10 male; mean age 82 ± 9 years) were identified in our database. A total of 20 patients (17 female, 3 male; mean age was 79 ± 9 years) were available for follow-up examination after a mean time period of approximately eight years (3–14 years) after revision surgery. At final follow-up, patients were assessed using a subjective shoulder value (SSV), range of motion (ROM), visual analogue score (VAS), the Constant Score (CS) and the 12-Item Short Form Survey (SF-12). Results: At final follow-up, mean CS was 55 ± 19 (19–91), VAS averaged 3 ± 3 (0–8) and mean SSV was 61 ± 18% (18–90%). Mean SF-12 was 44 (28–57) with a mean physical component summary (PCS) of 38 (21–56) and a mean mental component summary (MCS) of 51 (29–67). On average active forward flexion (FF) was 104° (10–170°), active abduction (ABD) was 101° (50–170°), active external rotation (ER) was 19° (10–30°) and active internal rotation (IR) of the lumbosacral transition was reached. Three patients presented with a periprosthetic humeral fracture after RTSA implantation and underwent a reoperation (15%) during follow-up period. Conclusions: Revision RTSA results in promising clinical results in patients after initial failed HA after PHF. A complication and reoperation rate of 15% is tolerable in consideration of satisfactory functional and psychological outcome. Trial registration: Retrospectively registered. [ABSTRACT FROM AUTHOR]

Purpose: Little is known about the outcomes that are most important to prosthesis users and funders. A Prosthetic Interventions Core Outcome Set (PI-COS) will help researchers and practitioners measure outcomes that are the most important to prosthesis users and funders. Materials and methods: Prosthesis users and funders rated the importance of 121 International Classification of Functioning, Disability, and Health (ICF) second-level categories using a two-round Delphi survey. A Consensus Meeting using the nominal group technique resolved rating differences between groups. The ICF second-level categories were ranked according to importance and a K-Means Cluster Analysis helped establish the PI-COS. Results: 65 users and 8 funders completed the Delphi surveys, followed by a Consensus Meeting. 26 ICF second-level categories were considered important to prosthesis users and funders and a PI-COS of 14 ICF second-level categories drawn predominantly from five ICF chapters was established: Sensory Functions and Pain (b2), Neuromusculoskeletal and Movement-related Functions (b7), General Tasks and Demands (d2), Mobility (d4), and Products and Technology (e1). Conclusions: The PI-COS describes the outcomes that are most important to prosthesis users and funders. The PI-COS can help focus on the most important outcome measures in clinical practice and research, including future prosthetic health economic evaluations. [ABSTRACT FROM AUTHOR]

The current primary treatment approach for malignant pelvic tumors involves hemipelvic prosthesis reconstruction following tumor resection. In cases of Enneking type II + III pelvic tumors, the prosthesis necessitates fixation to the remaining iliac bone. Prevailing methods for prosthesis fixation include the saddle prosthesis, ice cream prosthesis, modular hemipelvic prosthesis, and personalized prosthetics using three-dimensional printing. To prevent failure of hemipelvic arthroplasty protheses, a novel fixation method was designed and finite element analysis was conducted. In clinical cases, the third and fourth sacral screws broke, a phenomenon also observed in the results of finite element analysis. Based on the original surgical model, designs were created for auxiliary dorsal iliac, auxiliary iliac bottom, auxiliary sacral screw, and auxiliary pubic ramus fixation. A nonlinear quasi-static finite element analysis was then performed under the maximum load of the gait cycle, and the results indicated that assisted sacral dorsal fixation significantly reduces stress on the sacral screws and relative micromotion exceeding 28 μm. The fixation of the pubic ramus further increased the initial stability of the prosthesis and its interface osseointegration ability. Therefore, for hemipelvic prostheses, incorporating pubic ramus support and iliac back fixation is advisable, as it provides new options for the application of hemipelvic tumor prostheses. [ABSTRACT FROM AUTHOR]

Background: Bone and joint infections represent a major public health issue due to their increasing prevalence, their functional prognosis and their cost to society. Phage therapy has valuable anti-biofilm properties against prosthetic joint infections (PJI). The aim of this study was to establish the proportion of patients eligible for phage therapy and to assess their clinical outcome judged against all patients presenting with PJI. Method:. Patients admitted for periprosthetic joint infection (PJI) at a French general hospital between 2015 and 2019 were retrospectively included. Eligibility for phage therapy was determined based on French recommendations, with polymicrobial infections serving as exclusion criteria. Patients were categorized into two groups: those eligible and those ineligible for phage therapy. We analyzed their characteristics and outcomes, including severe adverse events, duration of intravenous antibiotic therapy, length of hospitalization, and relapse rates. Results:. In this study, 96 patients with PJI were considered in multidisciplinary medical meetings. Of these, 44% patients (42/96) were eligible for additional phage therapy. This group of patients had a longer duration of intravenous therapy (17 days vs. 10 days, p = 0.02), more severe adverse events (11 vs. 3, p = 0.08) and had a longer hospital stay (43 days vs. 18 days, p < 0.01). Conclusion:. A large number of patients met eligibility criteria for phage therapy and treatment and follow-up is more complex. A larger epidemiological study would more accurately describe the prognosis of eligible patients. [ABSTRACT FROM AUTHOR]

Montgomery's medialization thyroplasty is a laryngeal frame surgery to treat patients with unilateral vocal cord paralysis. This procedure uses a silicone implant in six sizes each for male and female patients. The results of this technique are generally good; however, the results can be suboptimal in some female patients because of differences in female and male laryngeal anatomy. The angle formed by the thyroid cartilage is greater in women than in men, meaning that the posterior portion of this cartilage is further away from the midline in women. We describe our results using male prostheses to improve suboptimal results in some of our female patients. This study is a retrospective case series study. We included female patients who underwent thyroplasty reintervention from 2014 to 2021 using male Montgomery thyroplasty prostheses. Functional results were studied using maximum phonation time (MPT), the GRBAS scales, and two questionnaires: Voice-Handicap Index 30 and Eating Assessment Tool 10. The functional results for all of these women improved after secondary thyroplasty. In one case, the MPT parameter did not change but patient satisfaction improved. The use of male Montgomery implants in women can be a useful tool to achieve improvement in female thyroplasty failure. [ABSTRACT FROM AUTHOR]

Introduction: Mason Type 3 radial-head fractures are typically treated with open reduction and internal fixation (ORIF) or radial-head arthroplasty (RHA). Prosthetic options include traditional monobloc implants and newer modular implants designed to match patient anatomy. While short- and medium-term outcomes of metallic RHA are generally favorable, this study aims to compare the long-term outcomes of patients treated with monobloc versus modular implants. Methods: The medical records of all the patients who underwent RHA at a level I trauma center between 2000 and 2011 were retrospectively reviewed. Patients who were available for follow-up were invited for reassessment, which included physical examination, questionnaires for the assessment of elbow pain and function, and follow-up radiographs. Results: Out of 35 patients who had RHA, 13 (37%) had a monobloc prosthesis and 22 (63%) had a modular prosthesis. Out of the patients that could be traced, 4 patients from the monobloc group and 10 patients from the modular group agreed to participate in the study. The mean follow-up time was 15 years in the monobloc group and 12.4 years in the modular group. Patients in the modular group demonstrated superior functional outcomes compared to the monobloc group, with statistically significant improvements in MEPS and DASH scores and a non-significant trend towards better ASES scores and VAS scores. Physical examination revealed a decline in function in the operated arm for both groups, with statistically significant differences favoring the modular group in elbow flexion and extension. Radiographic analysis showed varying degrees of implant loosening, with the modular group exhibiting less loosening compared to the monobloc group. Mild degenerative changes and heterotopic ossification were also observed, predominantly in the modular group. Conclusions: The results suggest that modular implants offer superior functional outcomes compared to monobloc implants. The modular group showed statistically significant improvements in elbow flexion and extension. These findings indicate that modular implants may be a more favorable option for enhancing patient outcomes. Further research with larger sample sizes is recommended to confirm these trends and to better understand the long-term benefits of modular implants. [ABSTRACT FROM AUTHOR]

The hallmark of neglected Ischemic Priapism is increasing tissue necrosis and hypoxia due to blocked venous outflow caused by unrelieved tissue pressure inside a confined compartment. inside six hours of start, irreversible changes to corporal tissue take place because of RIP, which causes time-dependent alterations inside the corpora cavernosa. While 50% of patients can maintain their erectile function if their priapism is treated within 24 hours, the maintenance of erectile function and the response rate to distal shunt procedures progressively decrease as priapism lengthens. Guidelines2022 from the American Urological Association state that once more conservative methods have failed, a distal penile shunt surgery is usually part of the management of neglected Ischemic Priapism. Distal shunts, such as intracavernosal tunneling, have poor results for protracted ischemic priapism, with just 30% of priapic episodes lasting more than 48 hours successfully treated. Penoscrotal corporal decompression (PSD) is a simple technique in the management of neglected Ischemic Priapismwith fewer complications & less cost with the restoration of erectile function than other techniques. PSD has favorable results in maintaining adequate sexual function as If PSD does not produce a long-lasting new shunt from the corpora cavernosa to the glans or spongiosum, there may be a greater chance of restoring physiological erectile function. [ABSTRACT FROM AUTHOR]

Objectives: This study compares hearing outcomes of two prosthesis materials, bone and titanium, used in ossiculoplasty. Design: This retrospective nationwide registry‐based study uses data systematically collected by the Swedish Quality Registry for Ear Surgery (SwedEar). Setting: The data were obtained from clinics in Sweden that perform ossiculoplasty. Participants: Patients who underwent ossiculoplasty using either bone or titanium prostheses were registered in SwedEar between 2013 and 2019. Main Outcome Measures: Hearing outcome expressed as air–bone gap (ABG) gain. Results: The study found no differences between bone and titanium for ABG or air conduction (AC) for either partial ossicular replacement prostheses (PORP) or total ossicular replacement prostheses (TORP). In a comparison between PORP and TORP for ABG and AC outcomes, regardless of the material used, PORP showed a small advantage, with an additional improvement of 3.3 dB (95% CI [confidence interval], 0.1–4.4) in ABG and 2.2 dB (95% CI, 1.7–4.8) in AC. In secondary surgery using TORP, titanium produced slightly better results for high‐frequency pure tone average. The success rate, a postoperative ABG ≤20 dB, was achieved in 62% of the operations for the whole group. Conclusion: Both bone and titanium used to reconstruct the ossicular chain produce similar hearing outcomes for both PORP and TORP procedures. However, titanium may be a preferable option for secondary surgeries involving TORP. The success rate, a postoperative ABG ≤20 dB, is consistent with other studies, but there is room for improvement in patient selection criteria and surgical techniques. [ABSTRACT FROM AUTHOR]

Abstract Wrist function is a top priority for transradial amputees. However, the combined functional, biomechanical, and cognitive impact of using a powered prosthetic wrist is unclear. Here, we quantify task performance, compensatory movements, and cognitive load while three transradial amputees performed a modified Clothespin Relocation Task using two myoelectric prostheses with and without the wrists. The two myoelectric prostheses include a commercial prosthesis with a built-in powered wrist, and a newly developed inexpensive prosthetic wrist for research purposes, called the “Utah wrist”, that can be adapted to work with various sockets and prostheses. For these three participants, task failure rate decreased significantly from 66% ± 12% without the wrist to 39% ± 9% with the Utah wrist. Compensatory forward leaning movements also decreased significantly, from 24.2° ± 2.5 without the wrist to 12.6° ± 1.0 with the Utah wrist, and from 23.6° ± 7.6 to 15.3° ± 7.2 with the commercial prosthesis with an integrated wrist. Compensatory leftward bending movements also significantly decreased, from 20.8° ± 8.6 to 12.3° ± 5.3, for the commercial with an integrated wrist. Importantly, simultaneous myoelectric control of either prosthetic wrist had no significant impact on cognitive load, as assessed by the NASA Task Load Index survey and a secondary detection response task. This work suggests that functional prosthetic wrists can improve dexterity and reduce compensation without significantly increasing cognitive effort. These results, and the introduction of a new inexpensive prosthetic wrist for research purposes, can aid future research and development and guide the prescription of upper-limb prostheses.

Introduction: Surgical removal of the lower jaw is the most common cause of mandibular deviation due to benign or malignant neoplasms. The Palatal Guide Flange Prosthesis (PGFP) is a recommended corrective appliance to reduce this clinical manifestation. The primary goals of rehabilitation with PGFP are to train the mandibular muscles and restore a healthy occlusal relationship so that the patient can effectively control their mouth opening and closing movements. In the present article, the Masticatory Performance (MP) of patients who had undergone hemi-mandibulectomy surgery was evaluated both before and after receiving an interim PGFP. Aim: To clinically evaluate MP pre- and post-mandibular guidance therapy in hemi-mandibulectomy patients. Materials and Methods: A quasi-experimental study was conducted on patients selected from the Outpatient Department of the Department of Prosthodontics at Bharati Vidyapeeth Dental College and Hospital, Sangli, Maharashtra, India, from January 2021 to July 2022, and were included as the sample size for the study. A total of 10 samples were selected. The study design was quasi-experimental. All cancer patients had lost their mandibular continuity and showed mandibular deviation toward the affected side. PGFPs were fabricated using Heat Cure Acrylic Resin (DPI) for each participant (n=10). Corn flakes (Kellogg’s) were given to the participants to chew, and the samples were sieved using a US standard 8-mesh sieve and collected at three different time intervals: T0 (preprosthesis), T1 (8th week), and T2 (16th week post-prosthesis). Data were entered into Microsoft Excel Version 13 and analysed using IBM Statistical Package for the Social Sciences (SPSS) version 21.0. Descriptive and inferential statistics were used, including mean and standard deviation for continuous variables and frequency analysis for categorical variables. For categorical variables, a Chi-square proportion test was utilised, and MP was evaluated between T0-T1 and T0-T2. We utilised a 95% confidence interval and a p-value of less than 0.05. Results: When comparing the MP between T0, T1 and T2 time intervals, it was found that the difference in mean MP was statistically significant (p

Objective Multi‐segmental total en bloc spondylectomy (TES) gradually became more commonly used by clinicians. However, the choice of surgical strategy is unclear. This study aims to investigate the biomechanical performance of different prosthesis types and fixation ranges in multisegmental TES. Methods In this study, a validated finite element model of T12–L2 post‐spondylectomy operations were carried out. The prostheses of these models used either 3D‐printed artificial vertebrae or titanium mesh cages. The fixed range was two or three segment levels. Range of motion, stress distribution of the endplate and internal fixation system, intervertebral disc pressure, and facet joint surface force of four postoperative models and intact model in flexion and extension, as well as lateral bending and rotation were analyzed and compared. Results The type of prosthesis used in the anterior column reconstruction mainly affected the stress of the adjacent endplate and the prosthesis itself. The posterior fixation range had a greater influence on the overall range of motion (ROM), the ROM of the adjacent segment, the stress of the screw‐rod system, and adjacent facet joint surface force. For the model of the same prosthesis, the increase of fixed length resulted in an obvious reduction of ROM. The maximal decrease was 70.23% during extension, and the minimal decrease was 30.19% during rotation. Conclusion In three‐segment TES, the surgical strategy of using 3D‐printed artificial prosthesis for anterior column support and pedicle screws for posterior fixation at both two upper and lower levels respectively can reduce the stress on internal fixation system, endplates, and adjacent intervertebral discs, resulting in a reduced risk of internal fixation failure, and ASD development.

Abstract Background Treatment options for correcting limb-length discrepancy after limb-salvage reconstruction for proximal tibial osteosarcoma in children have several limitations. Therefore, we aimed to evaluate the feasibility, complications, prognosis, and clinical outcomes of reconstruction using hemiarthroplasty after tumor resection in pediatric patients with proximal tibial osteosarcoma. Methods We conducted a comprehensive retrospective analysis of the data of pediatric patients with osteosarcoma of the proximal tibia who underwent surgery between December 2008 and November 2018 at our center. We enrolled 49 consecutive patients who underwent hemiarthroplasty. The cruciate ligaments of all patients were reconstructed using special spacers, and the medial and lateral collateral ligaments of the knee and joint capsule were reconstructed using a mesh. Postoperatively, if the unequal length of both lower limbs exceeded 4 cm or knee instability occurred, a second-stage surgery was performed for limb lengthening and replacing the distal femoral prosthesis. We analyzed the oncological prognosis, complications of hemiarthroplasty, postoperative stability, and postoperative function. Results The follow-up period ranged between 11 and 159 months, with a median of 84 (62, 129) months. The overall 5-year survival rate was 83.2%. Thirty-nine patients survived at the end of the follow-up period with 34 prostheses (87.2%). The overall prosthesis survival rate was 87.4% after 5 years, indicating the long-term benefits of the procedure. Limb length was measured in 28 adult patients. The average limb-length discrepancy was 33 ± 15 mm with a median of 33 mm (21, 47); the femur and tibia caused a discrepancy of 8.5 ± 9.9 mm and 24.8 ± 15.5 mm, respectively. The patients had 30–135° of knee motion, with a mean of 82 ± 24°. The femoral tibial angle was greater on the affected side than on the healthy side, with a mean difference of 4.5°±3.6°. The Musculoskeletal Tumor Society (MSTS) score was 25 ± 3. Five patients underwent second-stage distal femoral prosthesis replacement, with mean MSTS scores of 24 ± 2 and 28 ± 1 before and after second-stage surgery, respectively. Conclusions Hemiarthroplasty in children reduces limb-length discrepancy in adulthood by rebuilding cruciate ligaments, lateral collateral ligaments, and the joint capsule, thereby improving knee stability.

Abstract Background Self-adhesive resin cements (SARCs) are widely used for fixed prostheses, but incomplete cleaning near the gingival margin can cause inflammation. However, the factors influencing cement properties and the biological response of gingival fibroblasts to cement eluates are not well understood. This study examines the impact of two light-polymerizing units (LPUs) on the physical and chemical properties of two SARCs under simulated clinical conditions, as well as the subsequent response of human gingival fibroblasts (hGFs) to these eluates. Methods Dental cement discs of SARCs were polymerized using Kerr DemiPlus and 3 M Elipar DeepCure-S LED LPUs with or without a 2-mm thick zirconia screen. Physical properties (microhardness, surface roughness, residual monomers) were evaluated. hGFs’ cell viability, wound healing potency, and gene expression were assessed. Results Both Maxcem and RelyX exhibited reduced microhardness and increased surface roughness when polymerized through zirconia or with DemiPlus LPU. Higher residual monomers (HEMA and GDMA in Maxcem; TEGDMA in RelyX) concentration was observed with DemiPlus and zirconia polymerization. Maxcem polymerized with DemiPlus exhibited lower cell viability, impaired healing, and altered gene expression in hGFs compared to those polymerized with Elipar LPU. Gene expression changes included downregulated NRF2 and HO-1 and upregulated CCR-3. Conclusions Light-polymerizing Maxcem through zirconia with DemiPlus LPU compromised SARCs’ properties, leading to higher residual monomers and negatively impacting hGFs’ viability, healing, and gene expression. Careful material selection and polymerization techniques are crucial to minimize adverse effects on surrounding tissues. Clinical significance Clinicians should exercise caution when using LPUs and SARCs, especially when polymerizing through zirconia. This will help optimize the physical and chemical properties of SARCs and minimize potential adverse effects on the surrounding gingival soft tissues.

The article provides readers with a detailed overview of the AutoMedPrint technology, its advantages and opportunities, based on a number of studies and case examples. The AutoMedPrint system represents a significant advancement in the field of orthopedics, offering a comprehensive solution for the automated design and rapid production of personalized orthopedic and prosthetic devices through 3D printing technology. This paper details the system's capabilities and methodologies behind it, which include the design and manufacturing of various devices such as wrist hand orthoses (WHO) and ankle foot orthoses (AFO), among others. These devices are crafted using data obtained from precise anthropometric measurements, allowing for high customization to meet individual patient needs. The AutoMedPrint system enhances the quality of life for patients by providing devices that are not only functional and cost-effective but also rapidly produced, ensuring timely intervention. Case studies demonstrate the system's effectiveness in practical scenarios, highlighting its potential to revolutionize orthopedic care by integrating new materials and technologies that adapt to changing medical and patient requirements. The discussion extends to the lifecycle of the produced devices, emphasizing sustainability and continuous improvement, ensuring the system's relevance and efficacy in modern medical practice.

Abstract Background Bone and joint infections represent a major public health issue due to their increasing prevalence, their functional prognosis and their cost to society. Phage therapy has valuable anti-biofilm properties against prosthetic joint infections (PJI). The aim of this study was to establish the proportion of patients eligible for phage therapy and to assess their clinical outcome judged against all patients presenting with PJI. Method . Patients admitted for periprosthetic joint infection (PJI) at a French general hospital between 2015 and 2019 were retrospectively included. Eligibility for phage therapy was determined based on French recommendations, with polymicrobial infections serving as exclusion criteria. Patients were categorized into two groups: those eligible and those ineligible for phage therapy. We analyzed their characteristics and outcomes, including severe adverse events, duration of intravenous antibiotic therapy, length of hospitalization, and relapse rates. Results . In this study, 96 patients with PJI were considered in multidisciplinary medical meetings. Of these, 44% patients (42/96) were eligible for additional phage therapy. This group of patients had a longer duration of intravenous therapy (17 days vs. 10 days, p = 0.02), more severe adverse events (11 vs. 3, p = 0.08) and had a longer hospital stay (43 days vs. 18 days, p

Abstract The current primary treatment approach for malignant pelvic tumors involves hemipelvic prosthesis reconstruction following tumor resection. In cases of Enneking type II + III pelvic tumors, the prosthesis necessitates fixation to the remaining iliac bone. Prevailing methods for prosthesis fixation include the saddle prosthesis, ice cream prosthesis, modular hemipelvic prosthesis, and personalized prosthetics using three-dimensional printing. To prevent failure of hemipelvic arthroplasty protheses, a novel fixation method was designed and finite element analysis was conducted. In clinical cases, the third and fourth sacral screws broke, a phenomenon also observed in the results of finite element analysis. Based on the original surgical model, designs were created for auxiliary dorsal iliac, auxiliary iliac bottom, auxiliary sacral screw, and auxiliary pubic ramus fixation. A nonlinear quasi-static finite element analysis was then performed under the maximum load of the gait cycle, and the results indicated that assisted sacral dorsal fixation significantly reduces stress on the sacral screws and relative micromotion exceeding 28 μm. The fixation of the pubic ramus further increased the initial stability of the prosthesis and its interface osseointegration ability. Therefore, for hemipelvic prostheses, incorporating pubic ramus support and iliac back fixation is advisable, as it provides new options for the application of hemipelvic tumor prostheses.

Abstract Background Prosthetic joint infections (PJI) are recalcitrant, hard-to-treat infections and severe complications of joint arthroplasty. Therefore, there is a need to develop new effective treatment strategies, and animal models of high clinical relevance are needed. This study aimed to develop a detailed surgical protocol for hip hemiarthroplasty in Göttingen minipigs and a thorough post-mortem sampling protocol to pave the way for creating a minipig PJI model. Methods Three adult female Göttingen minipigs underwent surgery with insertion of a hip hemiarthroplasty, using the anterior approach to the hip joint. After surgery the minipigs were followed closely with daily clinical evaluation and gait scoring. Comprehensive post-mortem analyses were performed with evaluation of macroscopic lesions, microbiology, synovial fluid analysis and histology. Results The study resulted in the first Göttingen minipig with hip hemiarthroplasty and identified several points of awareness when inserting a hip prosthesis in minipigs, especially the high risk of joint dislocation. A spontaneous PJI occurred in one of the minipigs, revealing an impaired ability of the immune cells to reach the bacteria at the bone-prosthesis interface. Conclusion The present study provides a detailed description of surgical technique and post-mortem sampling and validates the suitability of the hip hemiarthroplasty minipig model for future experimental modeling of PJI.

Summary: Background: Augmentation mammoplasty with subpectoral prosthesis implantation is a frequent performed procedure in plastic surgery for reconstructive and aesthetic purposes. Although prosthesis implantation in a pocket under the major pectoralis muscle has been related to volumetric and functional alterations, there is not much information about the associated short- and long-term histological changes. Therefore, the aim of our study was to describe the acute and chronic histological muscle alterations associated with subpectoral prosthesis implantation. Materials and Method: We collected samples from patients with breast tissue expander (1 year after implantation) and from patients without implantation as a control group. The samples were processed for assessing their histological, histochemical and immunohistochemical properties. Results: In the control group, no relevant histological findings were identified. Additionally, in the patients with expander, we observed mild augmentation of the internalised nuclei, normal morphology, significant muscle atrophy and fibrosis, whereas in the patients with prosthesis considerable augmentation of internalised nuclei, significant muscle atrophy, fibrosis and alteration of normal muscle morphology were observed. Conclusion: Prosthesis implantation induces histological changes in the periprosthetic striated muscle. Chronic fibrosis and inflammation play key roles in this process, which should be characterised in more detail from the histological and molecular biological perspective.

The House of Commons Standing Committee on Health proposed in 2022 to start a national registry for breast implants. Why, and what requirements are needed, will be outlined. Breast implant products are not always in compliance with international norms and standards, and several scandals have occurred because of industry fraud. To trace which patients have defective breast implants, a good registry is an absolute must. Furthermore, some diseases, such as lymphomas, autoimmune diseases, and so-called breast implant illness, are believed to be associated with breast implants. An accurate estimation of how often these diseases occur in patients with breast implants is lacking. A registry in which not only surgical data but also patient-reported outcome measurements are recorded will result in a better understanding of patient outcomes and device performance. The registry should not be a voluntary ('opt-in') registry but a mandatory ('opt-out') registry, in which only the patient (and not the surgeon) has the choice whether to participate., It is estimated that 3%-4% of women in Western countries have silicone breast implants. Of these, 70% are placed for cosmetic reasons, whereas about 30% are placed for reconstruction after [...]

Montgomery’s medialization thyroplasty is a laryngeal frame surgery to treat patients with unilateral vocal cord paralysis. This procedure uses a silicone implant in six sizes each for male and female patients. The results of this technique are generally good; however, the results can be suboptimal in some female patients because of differences in female and male laryngeal anatomy. The angle formed by the thyroid cartilage is greater in women than in men, meaning that the posterior portion of this cartilage is further away from the midline in women. We describe our results using male prostheses to improve suboptimal results in some of our female patients. This study is a retrospective case series study. We included female patients who underwent thyroplasty reintervention from 2014 to 2021 using male Montgomery thyroplasty prostheses. Functional results were studied using maximum phonation time (MPT), the GRBAS scales, and two questionnaires: Voice-Handicap Index 30 and Eating Assessment Tool 10. The functional results for all of these women improved after secondary thyroplasty. In one case, the MPT parameter did not change but patient satisfaction improved. The use of male Montgomery implants in women can be a useful tool to achieve improvement in female thyroplasty failure.

Background: The knee joint must adapt to the changes in walking speed to stabilize the stance phase and provide fluency in the swing phase.Objective: This study aimed to report a comparison of the gait patterns of transfemoral amputees using a novel mechanical prosthetic knee that can adapt automatically to different walking speeds with 3R60 and 3R15 knee prostheses.Material and Methods: In this experimental study, biomechanical data were collected from six unilateral trans-femoral amputees walking with three knee prostheses. Gait data were gathered at slow, normal, and fast walking speeds across a 7-meter walkway using the Vicon motion system.Results: The results revealed a significant difference in knee angular velocity during the swing phase between prosthetic knees across three walking speeds (P-value=0.002). Prosthetic knee flexion decreased significantly by increasing walking speed for the novel mechanical auto-adaptive prosthetic knee (P-value

Objective To explore better methods of ceramic crown design and reduce foreign body sensation of prostheses by digitally replicating the lingual morphology of the original teeth in the patient's aesthetic zone. Methods Patients with anterior tooth defects were collected from July 2022 to December 2023 at Department of Second Clinical Division of the Affiliated Stomatological Hospital, Nanjing Medical University. Patients with crown prostheses designed using automatically matched tooth morphology from the tooth shape database served as the control group. Patients with crown prostheses designed using digital technology to replicate the lingual morphology of the original teeth were used as the experimental group. Differences in occlusal evaluation and foreign body sensation evaluation of the prostheses in the two groups were compared. Results Results showed that the minimal interocclusal distance of the experimental group was greater than that of the control group, and the difference was statistically significant. The occlusal evaluation of the prostheses in the experimental group was better than that of the control group, and the difference was statistically significant. The foreign body sensation of the prostheses in the experimental group was also less than that of the control group. Conclusion Prostheses designed using digital technology to replicate the original lingual morphology of the teeth have a better lingual occlusal relationship with less foreign body sensation and better comfort.

Abstract Background Patient access to body-powered and myoelectric upper limb prostheses in the United States is often restricted by a healthcare system that prioritizes prosthesis prescription based on cost and perceived value. Although this system operates on an underlying assumption that design differences between these prostheses leads to relative advantages and disadvantages of each device, there is limited empirical evidence to support this view. Main text This commentary article will review a series of studies conducted by our research team with the goal of differentiating how prosthesis design might impact user performance on a variety of interrelated domains. Our central hypothesis is that the design and actuation method of body-powered and myoelectric prostheses might affect users’ ability to access sensory feedback and account for device properties when planning movements. Accordingly, other domains that depend on these abilities may also be affected. While our work demonstrated some differences in availability of sensory feedback based on prosthesis design, this did not result in consistent differences in prosthesis embodiment, movement accuracy, movement quality, and overall kinematic patterns. Conclusion Collectively, our findings suggest that performance may not necessarily depend on prosthesis design, allowing users to be successful with either device type depending on the circumstances. Prescription practices should rely more on individual needs and preferences than cost or prosthesis design. However, we acknowledge that there remains a dearth of evidence to inform decision-making and that an expanded research focus in this area will be beneficial.

The distal femur is one of the most common sites for primary bone tumors. As the tumor progresses and bone destruction worsens, it can severely affect knee function and even pose a threat to life. In cases where only one condyle is affected and requires resection, preserving the healthy contralateral condyle can substantially enhance the biomechanics of the knee. Furthermore, preserving bone stock may enable future salvage procedures in the event of initial surgery failure, be it from fractures or osteoarthritis. Distal femoral unicondyle resection can offer better functional outcomes in select cases. However, it is essential to prioritize oncological safety with adequate margins over short‐term knee function. Currently, the primary methods for reconstruction after the excision of a unicondylar tumor include allograft transplantation (bi‐ or uni‐condylar) and prosthetic or allograft‐prosthesis composite replacement (APC). However, there is currently some controversy regarding the optimal surgical reconstruction method, and a consensus within the academic community has yet to be reached. Moreover, due to the rarity of bone tumors, extensive clinical data from a single center is limited. Current studies are mainly retrospective and single‐center, lacking sufficient cases and follow‐up duration. This article reviews surgical reconstruction after solitary condylar excision in distal femoral tumors. It summarizes, compares, and analyzes mainstream reconstruction methods, exploring their technical details and clinical outcomes to highlight their potential in bone oncology.

Purpose Three‐level hybrid surgery (HS) consisting of cervical disc arthroplasty (CDA) and anterior cervical discectomy and fusion (ACDF) has been partly used for the treatment of multi‐level cervical degenerative disc disease (CDDD). The complications related to the implants and the collapse of the surgical vertebral bodies had been reported in multi‐level anterior cervical spine surgery. Thus, this study aimed to explore the biomechanical effects on the prostheses and vertebrae in three‐level HS. Methods A FE model of cervical spine (C0‐T1) was constructed. Five surgical models were developed. They were FAF model (ACDF‐CDA‐ACDF), AFA model (CDA‐ACDF‐CDA), FFF model (three‐level ACDF), SF model (single‐level ACDF), and SA model (single‐level CDA). A 75‐N follower load and 1.0‐N·m moment was applied to produce flexion, extension, lateral bending, and axial rotation. Results Compared with the intact model, the range of motion (ROM) of total cervical spine in FAF model decreased by 34.54%, 54.48%, 31.76%, and 27.14%, respectively, in flexion, extension, lateral bending, and axial rotation, which were lower than those in FFF model and higher than those in AFA model. The ROMs of CDA segments in FAF and AFA models were similar to the intact model and SA model. Compared with the intact model, the ROMs at C3/4 segment in FFF model increased from 5.71% to 7.85%, and increased from 5.31% to 6.81% at C7/T1 segment, following by FAF model, then the FAF model. The maximum interface pressures of the Prestige‐LP in FAF model were similar to SA model, however the corresponding values were increased in AFA model. The maximum interface pressures of the Zero‐P were increased in FAF and AFA model compared with those in SF and FFF models. The stress was mainly distributed on the screws. In AFA model, the maximum pressures of the ball and trough articulation in superior and inferior Prestige‐LP were all increased compared with those in SA and FAF model. In FFF model, the maximum pressures of the vertebrae were higher than those in other models. The stress was mainly distributed on the anterior area of the vertebral bodies. Conclusions HS seemed to be more suitable than ACDF for the surgical treatment of three‐level CDDD in consideration of the biomechanical effects, especially for the two‐level CDA and one‐level ACDF construct. But a more appropriate CDA prosthesis should be explored in the future.

Abstract Background This case highlights several complications of a late and rare presentation of culture-negative Streptococcus pyogenes endocarditis of a previously repaired mitral valve with an annuloplasty ring including recurrent cardioembolic strokes, which was initially missed on transthoracic echocardiography. Case presentation A 66-year-old Caucasian female with prior mitral valve prolapse status post mitral valve annuloplasty and left atrial appendage occlusion, followed by two strokes, presented with supraventricular tachycardia that resolved spontaneously. During an inpatient admission, she developed symptoms of another stroke, and imaging studies were suggestive of recurrent cardioembolic phenomenon. Additional workup revealed two small intra-atrial masses adherent to the mitral annuloplasty ring missed on prior evaluation for recurrent stroke. She underwent surgical repair in the setting of a chronic culture-negative infectious endocarditis with Streptococcus pyogenes and recovered well with no further cardioembolic phenomenon. Conclusion This case serves to highlight the importance of having a higher index of suspicion in any cardiac prosthesis patient for endocarditis when presenting with symptoms such as recurrent stroke, arrhythmias, and abnormal cardiac lab work. It also demonstrates the need for appropriate imaging with transthoracic echocardiography followed by transesophageal echocardiography and reviews surgical indications to diagnose and treat culture-negative endocarditis.

Frontal plane ankle motion is important for balance in walking but is seldom controlled in robotic prostheses. This article describes the design, control and performance of a semi-active two-degree-of-freedom robotic prosthetic ankle. The mechanism uses a non-backdrivable wedge cam system based on rotating inclined planes, allowing actuation only during swing phases for low power, light weight and compactness. We present details of the mechanism and its kinematic and mechatronic control, and a benchtop investigation of the system’s speed and accuracy in ankle angle control. The two-axis ankle achieves angular reorientation movements spanning ±10 deg in any direction in less than 0.9 s. It achieves a plantarflexion/dorsiflexion error of 0.35 ± 0.27 deg and an inversion/eversion error of 0.29 ± 0.25 deg. Backdriven motion during walking tests is negligible. Strengths of the design include self-locking behavior for low power and simple kinematic control. Two-axis ankle angle control could enable applications such as balance augmentation, turning assistance, and wearable perturbation training.

Abstract Background This research assessed three materials to be used in the fabrication of fixed free fixed dental prosthesis using finite element analysis. Total deformation, Von Mises stress maximum amounts and sites on both the bone, and the fixed dental prosthesis body were compared. Methods 3D finite element model was made for the tested fixed dental prosthesis and a contact scanner was used. A fixed free dental prosthesis was made restoring the maxillary first premolar, where second premolar with first molar were the supporting abutments that were scanned. Porcelain fused to metal, CEREC Tessera (Dentsply Sirona) and Poly-Ether-Ketone-Ketone were assessed as fixed free dental prosthesis materials. Cement thickness was adjusted to 40 microns. 100 N vertical load was applied to the central fossa of the pontic in the model. Results The deformations in this study were within the acceptable range except with the PEKK fixed free prosthesis. Tessera showed better results than the porcelain fused to metal as the more elastic modulus allows for absorption of energy from loading. Conclusions Purely used PEKK is not recommended for fixed free dental prosthesis. Low stiffness fixed dental prosthesis material helps in transferring low amount of load to the underneath tissues.

Background: Satisfaction with prosthesis plays a key role in regaining mobility and is important for optimizing prosthetic usage, mobility, and increasing compliance with medical regimen. Despite unchangeable factors like age and comorbidities, other factors, like pain, received rehabilitation, satisfaction with assistive devices, service, and information, can be changed and might contribute to a better usage and acceptance of the prosthesis and amputees' mobility. Objectives: The aim of the study was to analyze mobility, pain, supply of assistive devices, and additional therapies received after major limb amputations. Furthermore, a correlation of those parameters was evaluated. Methods: Retrospective identification of patients with major limb amputation (operation and procedures classification system (OPS)) and relevant related demographics within the clinical documentation system during a four-year observation time. In addition, we undertook prospective assessment of mobility (K-level), pain qualities, additional therapies, self-rated overall quality of life (QoL) and degree of adaptation to the life after amputation, dependency from caregivers, and satisfaction with the provided assistive devices (QUEST). Results: A total of 164 patients (mean age 68, age range: 19 to 97 years) underwent major limb amputation. A total of 27 questionnaires were returned and analyzed. All those traumatic and nontraumatic amputees received assistive devices. Although mobility and QoL decreased significantly after amputation, a high satisfaction with provided prosthetic and assistive devices and care was found. Conclusions: Amputation registries are becoming elementary to allow for nationwide comparisons of clinics, to identify the requirements of amputees, and to design an interdisciplinary care model for a successful comprehensive approach. [ABSTRACT FROM AUTHOR]

This study investigated the impact of early prosthetic intervention on children with upper limb agenesis or amputation. The aim was to assess both how early prosthetics improve a child's movement and coordination skills, as well as how satisfied both the child and their parents are with the prosthesis. Twenty-nine children were evaluated using the Unilateral Below Elbow Test (UBET) and Child Amputee Prosthetics Project—Prothesis Satisfaction Inventory (CAPP-PSI). Results suggest that while children performed tasks faster and more fluidly without a prosthesis, they were satisfied with the prostheses and the service provided. This may be due to ongoing adaptation to the new device. The single child re-evaluated at 12 months showed improvement in prosthesis use, highlighting the potential benefits of early intervention coupled with motor re-education. Further research is needed to optimize prosthetic features and address initial challenges associated with prosthesis use. [ABSTRACT FROM AUTHOR]

AbstractPurposeMaterials and methodsResultsConclusions\nIMPLICATIONS FOR REHABILITATIONTo evaluate the psychometric properties of the Arabic version of the Activities-Specific Balance Confidence Scale using the 5-option response categories for individuals with lower limb amputation (ABC-5/Ar).This was a methodological study on a convenience sample of individuals with unilateral lower-limb amputation attending outpatient rehabilitation centres in Saudi Arabia and Turkey (N = 155). Rasch analysis (WINSTEPS version 4.6.5) was used to examine the 5-categories rating scale structure, item fit, item difficulty hierarchy, person separation index, unidimensionality, local item dependency, and differential item functioning.The ABC-5/Ar 5-response option demonstrated an appropriate model fit. Most items fit the Rasch model, except for item #12 “walk in a crowded mall,” which showed an overfitting value of 0.63. The person separation indices 2.95 (Cronbach’s α = 0.96). Principal component analysis of residuals confirmed the unidimensionality of the scale; however, local dependency was detected between item #14 “Ride in escalator holding rail,” and item #15 “Ride in escalator not holding rail.”The findings suggest that the ABC-5/Ar shows promise in assessing balance confidence in Arabic-speaking lower-limb prosthesis users. However, further studies with larger sample sizes and in diverse clinical contexts are needed to confirm its effectiveness in various clinical settings.Overall, our Rasch-based study provides additional evidence to support the psychometric appropriateness of using the Activity-specific Balance Confidence scale with the 5-category options (ABC-5) of the Arabic version among lower prosthesis users.Clinicians and researchers should be mindful of cultural and contextual differences that exist among Arabic-speaking population which may influence how participants responded to certain items in the scale.It is essential to conduct a comprehensive psychometric evaluation to guide the implementation and interpretation of scales, particularly in Arabic-speaking countries due to the scarcity of validated and standardised outcome measures to assess prosthesis users’ confidenceOverall, our Rasch-based study provides additional evidence to support the psychometric appropriateness of using the Activity-specific Balance Confidence scale with the 5-category options (ABC-5) of the Arabic version among lower prosthesis users.Clinicians and researchers should be mindful of cultural and contextual differences that exist among Arabic-speaking population which may influence how participants responded to certain items in the scale.It is essential to conduct a comprehensive psychometric evaluation to guide the implementation and interpretation of scales, particularly in Arabic-speaking countries due to the scarcity of validated and standardised outcome measures to assess prosthesis users’ confidence [ABSTRACT FROM AUTHOR]

Background: Patient access to body-powered and myoelectric upper limb prostheses in the United States is often restricted by a healthcare system that prioritizes prosthesis prescription based on cost and perceived value. Although this system operates on an underlying assumption that design differences between these prostheses leads to relative advantages and disadvantages of each device, there is limited empirical evidence to support this view. Main text: This commentary article will review a series of studies conducted by our research team with the goal of differentiating how prosthesis design might impact user performance on a variety of interrelated domains. Our central hypothesis is that the design and actuation method of body-powered and myoelectric prostheses might affect users' ability to access sensory feedback and account for device properties when planning movements. Accordingly, other domains that depend on these abilities may also be affected. While our work demonstrated some differences in availability of sensory feedback based on prosthesis design, this did not result in consistent differences in prosthesis embodiment, movement accuracy, movement quality, and overall kinematic patterns. Conclusion: Collectively, our findings suggest that performance may not necessarily depend on prosthesis design, allowing users to be successful with either device type depending on the circumstances. Prescription practices should rely more on individual needs and preferences than cost or prosthesis design. However, we acknowledge that there remains a dearth of evidence to inform decision-making and that an expanded research focus in this area will be beneficial. [ABSTRACT FROM AUTHOR]

Purpose: Three‐level hybrid surgery (HS) consisting of cervical disc arthroplasty (CDA) and anterior cervical discectomy and fusion (ACDF) has been partly used for the treatment of multi‐level cervical degenerative disc disease (CDDD). The complications related to the implants and the collapse of the surgical vertebral bodies had been reported in multi‐level anterior cervical spine surgery. Thus, this study aimed to explore the biomechanical effects on the prostheses and vertebrae in three‐level HS. Methods: A FE model of cervical spine (C0‐T1) was constructed. Five surgical models were developed. They were FAF model (ACDF‐CDA‐ACDF), AFA model (CDA‐ACDF‐CDA), FFF model (three‐level ACDF), SF model (single‐level ACDF), and SA model (single‐level CDA). A 75‐N follower load and 1.0‐N·m moment was applied to produce flexion, extension, lateral bending, and axial rotation. Results: Compared with the intact model, the range of motion (ROM) of total cervical spine in FAF model decreased by 34.54%, 54.48%, 31.76%, and 27.14%, respectively, in flexion, extension, lateral bending, and axial rotation, which were lower than those in FFF model and higher than those in AFA model. The ROMs of CDA segments in FAF and AFA models were similar to the intact model and SA model. Compared with the intact model, the ROMs at C3/4 segment in FFF model increased from 5.71% to 7.85%, and increased from 5.31% to 6.81% at C7/T1 segment, following by FAF model, then the FAF model. The maximum interface pressures of the Prestige‐LP in FAF model were similar to SA model, however the corresponding values were increased in AFA model. The maximum interface pressures of the Zero‐P were increased in FAF and AFA model compared with those in SF and FFF models. The stress was mainly distributed on the screws. In AFA model, the maximum pressures of the ball and trough articulation in superior and inferior Prestige‐LP were all increased compared with those in SA and FAF model. In FFF model, the maximum pressures of the vertebrae were higher than those in other models. The stress was mainly distributed on the anterior area of the vertebral bodies. Conclusions: HS seemed to be more suitable than ACDF for the surgical treatment of three‐level CDDD in consideration of the biomechanical effects, especially for the two‐level CDA and one‐level ACDF construct. But a more appropriate CDA prosthesis should be explored in the future. [ABSTRACT FROM AUTHOR]

The distal femur is one of the most common sites for primary bone tumors. As the tumor progresses and bone destruction worsens, it can severely affect knee function and even pose a threat to life. In cases where only one condyle is affected and requires resection, preserving the healthy contralateral condyle can substantially enhance the biomechanics of the knee. Furthermore, preserving bone stock may enable future salvage procedures in the event of initial surgery failure, be it from fractures or osteoarthritis. Distal femoral unicondyle resection can offer better functional outcomes in select cases. However, it is essential to prioritize oncological safety with adequate margins over short‐term knee function. Currently, the primary methods for reconstruction after the excision of a unicondylar tumor include allograft transplantation (bi‐ or uni‐condylar) and prosthetic or allograft‐prosthesis composite replacement (APC). However, there is currently some controversy regarding the optimal surgical reconstruction method, and a consensus within the academic community has yet to be reached. Moreover, due to the rarity of bone tumors, extensive clinical data from a single center is limited. Current studies are mainly retrospective and single‐center, lacking sufficient cases and follow‐up duration. This article reviews surgical reconstruction after solitary condylar excision in distal femoral tumors. It summarizes, compares, and analyzes mainstream reconstruction methods, exploring their technical details and clinical outcomes to highlight their potential in bone oncology. [ABSTRACT FROM AUTHOR]

• An improved prosthesis structure was proposed. • The improved prosthesis can reduce the pressure in the intervertebral disc of the adjacent segment, the contact stress of the facet joint and the artificial prosthesi. Artificial lumbar disc replacement is an effective method for the treatment of lumbosacral degenerative diseases. An appropriate artificial intervertebral disc device is of great significance for the maintenance of spinal stability and activity. Two finite element models of ProDisc-L prosthesis replacement and improved prosthesis replacement were constructed by using the finite element model of complete lumbar L1-L5 segment established by CT image data. The mechanical properties of the surgical models before and after improvement were analyzed and evaluated. The ProDisc-L group and the improved group showed similar lumbar's ROM and maintained a similar ROM with the normal lumbar spine. There was no significant change in the intervertebral disc's pressure between the adjacent segments of the two prosthesis groups compared with the normal group, but the stress value of the improved prosthesis group was slightly lower than that of the ProDisc-L group. In addition, the improved prosthesis replacement has more reasonable stress distribution. Compared with the ProDisc-L prosthesis, the improved prosthesis can reduce the pressure in the intervertebral disc of the adjacent segment, the contact stress of the facet joint and the artificial prosthesis, which provides reference for the subsequent design of the prosthesis structure. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate existing staging recommendations for peri-implantitis and its applicability for auricular bone anchoring. In this cross-sectional study, 44 patients treated with 47 ear epitheses and 128 implants were analyzed over 191.6 months (mean). Peri-implant sulcus depth, sulcus fluid flow rate, and peri-implant skin reaction, as well as cleaning habits and patients' quality of life, were analyzed. Mixed effect linear and mixed effect ordered logistic regression models were used. Two of the 128 implants were lost (1.6 %). A total of 14.5 % of all patients presented light erythemas, 19.4 % showed stage 2, 4.8 % stage 3, and 12.9 % an acute infection according to Holgers. A correlation between skin reaction and sulcus fluid flow rate was observed, when grouping patients with acute signs of inflammation. Concerning patient satisfaction, 58.1 % of the patients were highly satisfied with their epitheses, 39.5 % very satisfied, and one patient was just satisfied. Younger age correlated with lower satisfaction rates. Implant-retained auricular epitheses are a safe, highly sufficient and satisfying way of extending ear reconstruction. Sulcus depth and skin reaction are quick and valuable assessment tools in auricular implants, but skin reaction alone was clinically insufficient to predict peri-implant pocket inflammation. [ABSTRACT FROM AUTHOR]

Chin prosthesis implantation, a cosmetic procedure to correct chin asymmetry, depression, or retraction, is generally safe and simple. However, its long-term effects on surrounding tissues are a concern. This study aimed to use three-dimensional (3D) scanning to classify the mentalis muscle shapes and assess the impact of prosthesis implantation on these muscles. This study evaluated 450 eligible female participants. Using three-dimensional imaging, data on the types, thickness, width, and length of the left and right mentalis muscles were collected and summarized. The impact of chin prosthesis on these muscle dimensions was assessed using analysis of variance, and the effect on muscle type was determined using χ 2 test. Chin implant placement affected the mentalis muscles, resulting in increased length, thickness, and width. The subjects' mentalis muscles were categorized into 3 types and divided into 7 subtypes. χ 2 test results indicated that implantation influences the classification of these muscles. Recognizing how implant placement affects the mentalis muscle can guide the development of treatments to mitigate these changes. Additionally, understanding the muscle's morphology enables more precise treatment approaches for patients. [ABSTRACT FROM AUTHOR]