Search Results (181)

The surface quality of biomedical implants, such as shoulder joint caps, plays a critical role in their performance, longevity, and biocompatibility. Most biomedical shoulder joints fail to reach their optimal functionality when finished through conventional techniques like grinding and lapping due to their inability to achieve nanometer-grade smoothness, which results in greater wear and friction along with potential failure. The advanced magnetorheological finishing (MRF) approach provides enhanced surface quality through specific dimensional control material removal. This research evaluates how MRF treatment affects the surface roughness performance and microhardness properties and wear resistance behavior of cobalt–chromium alloy shoulder joint caps which have biocompatible qualities. The study implements a magnetorheological finishing system built with an electromagnetic tool to achieve the surface roughness improvements from 0.35 µm to 0.03 µm. The microhardness measurements show that MRF applications lead to a rise from HV 510 to HV 560 which boosts the wear protection of samples. After MRF finishing, the coefficient of friction demonstrates a decrease from 0.12 to 0.06 which proves improved tribological properties of these implants. The results show that MRF technology delivers superior benefits for biomedical use as it extends implant life span and decreases medical complications leading to better patient health outcomes. The purposeful evaluation of finishing techniques and their effects on implant functionality demonstrates MRF is an advanced technology for upcoming orthopedic implants while yielding high precision and enhanced durability and functional output. Full article

Background: Surgical neck nonunions of the proximal humerus present a complex clinical challenge, especially in elderly patients with pre-existing glenohumeral arthritis. Reverse total shoulder arthroplasty (RTSA) offers a reliable treatment option in these cases; however, resection of the tuberosities may compromise joint stability, increase the risk of postoperative dislocation and compromise postoperative function. This article describes a reproducible RTSA technique that preserves and repairs the greater and lesser tuberosities, aiming to enhance construct stability and optimize outcomes. Methods: We present a 74-year-old female with underlying glenohumeral arthritis who underwent RTSA for a symptomatic surgical neck nonunion via an extended deltopectoral approach. The nonunion is first mobilized, and tuberosity osteotomies are performed. After implant placement, the tuberosities are secured to the implant, to each other, and to the humeral shaft. A cerclage suture is also passed circumferentially to reinforce the repair and prevent posterior gapping. Results: The patient regained her pre-injury level of function by her last follow-up. She had pain-free, active forward elevation to 110 degrees and radiographic evidence of maintained tuberosity reduction and healing. There was no evidence of instability. Conclusions: In conclusion, incorporating tuberosity preservation and repair into RTSA for proximal humerus nonunion may reduce dislocation risk and improve functional recovery in elderly, low-demand patients. Full article

Background and Clinical Significance: Evaluating wide complex rhythms in patients with permanent pacemakers can be a diagnostic challenge, particularly when the rhythm is irregular. While pacemaker-mediated rhythms are typically regular and predictable, the appearance of wide complex irregular rhythms raises concerns ranging from lead malfunction to life-threatening arrhythmias, such as ventricular tachycardia. Understanding the interplay between intrinsic cardiac activity and device function is crucial for timely and accurate diagnosis in this increasingly common clinical scenario. Case presentation: We report on a 74-year-old female with a VVI pacemaker implanted for binodal disease, who presented with intermittent palpitations and an irregular rhythm. The patient has a recent history of falling on her right shoulder, which is also the site of the device implantation. We used a clinical step-by-step approach to rule out pacemaker malfunction and to establish the need for an unscheduled device interrogation. Conclusions: This case presentation highlights the important role of clinical reasoning and the approach to such a patient, especially when a key method of pacemaker evaluation, such as device interrogation, is not readily available. Full article

Two-dimensional imaging is still commonly used in dentistry, but does not provide the three-dimensional information often required for the accurate assessment of dental structures. Photon-counting computed tomography (PCCT), a new three-dimensional modality mainly used in general medicine, has shown promising potential for dental applications. With growing digitalization and cross-disciplinary integration, using PCCT data from other medical fields is becoming increasingly relevant. Conventional CT scans, such as those of the cervical spine, have so far lacked the resolution to reliably evaluate dental structures or implants. This study evaluates the diagnostic utility of PCCT for visualizing peri-implant structures in routine clinical photon-counting CT acquisitions and assesses the influence of metal artifact reduction (MAR) algorithms on image quality. Ten dental implants were retrospectively included in this IRB-approved study. Standard PCCT scans were reconstructed at multiple keV levels with and without MAR. Quantitative image analysis was performed with respect to contrast and image noise. Qualitative evaluation of peri-implant tissues, implant shoulder, and apex was performed independently by two experienced dental professionals using a five-point Likert scale. Inter-reader agreement was measured using intraclass correlation coefficients (ICCs). PCCT enabled high-resolution imaging of all peri-implant regions with excellent inter-reader agreement (ICC > 0.75 for all structures). Non-MAR reconstructions consistently outperformed MAR reconstructions across all evaluated regions. MAR led to reduced clarity, particularly in immediate peri-implant areas, without significant benefit from energy level adjustments. All imaging protocols were deemed diagnostically acceptable. This is the first in vivo study demonstrating the feasibility of opportunistic dental diagnostics using PCCT in a clinical setting. While MAR reduces peripheral artifacts, it adversely affects image clarity near implants. PCCT offers excellent image quality for peri-implant assessments and enables incidental detection of dental pathologies without additional radiation exposure. PCCT opens new possibilities for opportunistic, three-dimensional dental diagnostics during non-dental CT scans, potentially enabling earlier detection of clinically significant pathologies. Full article

Background: Ferrous metals are used extensively in the manufacturing of plates, pins, Kirschner wires (K-wires), and screws, and in the performance of partial and total joint replacement surgeries for the shoulder, elbow, and wrist joints. The primary surgical procedures commonly performed are hip and knee replacement surgeries. Metals possess a combination of high modulus, yield point, and ductility, rendering them well suited for load-bearing applications, as they can withstand significant loads without experiencing substantial deformations or permanent alterations in their dimensions. Application of metals and alloys is of prime importance in orthopedics as they lead the way to overcoming many issues encountered in implant use. In some instances, pure metals are used, but alloys consisting of two or more elements typically exhibit greater material characteristics, including corrosion resistance as well as toughness. The first item to address when selecting a metallic implant material is its biocompatibility. In this regard, three classes of materials are also commonly known as biomedical metals—316L stainless steel, pure titanium, and titanium alloys. Objective: The aim of this work is to create a model describing the material behavior and then simulate the metals under a load of 2300 N, which is equivalent to plastic loading. Methods: Under ten different case studies, a sub-routine was developed to combine the material characteristics of titanium and 316L stainless steel with the software. Results: The outcomes of the research were then investigated. A femur model was created using ANSYS software, and two materials, stainless steel and titanium, were used. The model was then exposed to a force of 2300 N. Full article

Background: Acromioclavicular (AC) joint dislocations are frequent, especially kocsisamong young male athletes. While over 150 surgical techniques exist, consensus on optimal treatment—particularly for Rockwood type III injuries—remains elusive. This study evaluates the Lockdown procedure’s efficacy, safety, and patient satisfaction, a synthetic ligament technique for AC joint stabilization. Methods: A multicenter prospective study was conducted on 39 patients across three Hungarian hospitals (2018–2023). Outcomes included shoulder function, pain levels, and complication rates, with subgroup analysis of acute (≤3 weeks) versus chronic (>3 weeks) cases. A systematic review of nine studies (205 cases) was also performed to assess broader outcomes and complications. Results: Significant improvements were observed in functional scores (OSS, Constant, DASH, SST, ASES, Nottingham, Imitani) and pain reduction, especially in acute cases with no prior shoulder surgery. The mean patient age was 38.9 ± 12.68 years, with a 24.5-month average follow-up. OSS improvement between acute and chronic cases was 14.96 (95% CI: 6.45–23.47; p = 0.0017). Complications (30.8%) occurred in eleven patients, mainly minor infections; implant failure necessitated revision in 5.1%. The systematic review reported a 34.6% complication rate (predominantly minor complications, like asymptomatic subluxation −16%) and 5.4% implant removal due to failure. A meta-analysis was not feasible due to data heterogeneity. Conclusions: The Lockdown procedure significantly enhances shoulder function and reduces pain, particularly in acute dislocations. However, the procedure showed a moderate complication rate, underscoring the need for careful patient selection and postoperative management. Full article

Background and Objectives: Many middle-aged and older individuals experience shoulder pain, often due to partial-thickness rotator cuff tears (PTRCTs). If conservative treatment fails to relieve symptoms in a patient, surgical intervention may be necessary. In such cases, using a bioinductive collagen implant may offer a viable alternative to conventional rotator cuff repair. Most notably, it offers potential advantages, particularly in reducing postoperative pain and promoting faster recovery. Accordingly, this study aims to evaluate the clinical outcomes of treating bursal-sided partial-thickness rotator cuff tears using bioinductive collagen implants alone, without concurrent rotator cuff repair. Materials and Methods: We followed 32 patients who had bursal-sided partial-thickness rotator cuff tears (Ellman grade I or II) and received conservative care for more than six months but continued to experience symptoms. These patients received surgery using bioinductive collagen implants without rotator cuff repair, and we followed up on their postoperative prognosis for at least one year after surgery. For a more accurate contrast, we performed clinical evaluation preoperatively and at 2 weeks, 6 weeks, 3 months, 6 months, and 12 months postoperatively. Visual Analog Scale (VAS), American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation (SANE), and Western Ontario Rotator Cuff (WORC) score were used as assessment tools in this study. As for radiological outcomes, magnetic resonance imaging (MRI) and ultrasonography were helpful. This supported our assessment of graft integration and failure. Results: These 32 patients included 13 with Ellman grade I tear and 19 with grade II tear. In both cases, they underwent surgery only using bioinductive collagen implants, and any anchor-based cuff repair was completely excluded. As for VAS (3.8 ± 2.9), certain statistically significant improvements were found starting at 2 weeks postoperatively. On the other hand, the scores of ASES (58.6 ± 20.3), SANE (60.1 ± 23.2), and WORC (59.8 ± 22.4) began to indicate a significant improvement starting at 6 weeks postoperatively (p < 0.001), showing continuous progress. At each final step, we confirmed that there were no cases of graft failure by radiological evaluation and found successful healing indicators, such as much less pain in all patients. Conclusions: The findings of this study provide the clinical evidence that a surgery using bioinductive collagen implant for bursal-sided partial-thickness rotator cuff tears is a highly effective treatment option in patients unresponsive to conservative therapy. Particularly, its practical clinical effectiveness includes facilitating rapid recovery without a significant risk of complications. Full article

Background: Bone elasticity is one of the most important biomechanical parameters of the skeleton. It varies markedly with age, anatomical zone, bone type (cortical or trabecular) and bone marrow status. Methods: This review presents the result of a systematic review and analysis of 495 experimental and analytical papers on the elastic properties of bone tissue. The bone characteristics of hip, shoulder, skull, vertebrae as a function of the factors of age (young and old), sex (male and female), presence/absence of bone marrow and different test methods are examined. The Bayesian neural network (BNN) was used to estimate the uncertainty in some skeletal parameters (age, sex, and body mass index) in predicting bone elastic modulus. Results: It was found that the modulus of elasticity of cortical bone in young people is in the range of 10–30 GPa (depending on the type of bone), and with increasing age, this slightly decreases to 10–25 GPa, while trabecular tissue varies from 0.2 to 5 GPa and reacts more acutely to osteoporosis. Bone marrow, according to several studies, is able to partially increase stiffness under impact loading, but its contribution is minimal under slow deformations. Conclusions: BNN confirmed high variability, supplementing the predictions with confidence intervals and allowed the formation of equations for the calculation of bone tissue elastic modulus for the subsequent selection of the recommended elastic modulus of the finished implant, taking into account the biomechanical characteristics of bone tissue depending on age (young and old), sex (men and women) and anatomical zones of the human skeleton. Full article

Background: Over the past few decades, shoulder arthroplasty has evolved rapidly, driven by a growing demand for surgical solutions to degenerative, traumatic, and irreparable rotator cuff-related pathologies, particularly in an aging but increasingly active population. Objective: This narrative review aims to examine the main clinical indications and the most commonly used implant designs, highlighting differences in functional outcomes, complication rates, and revision rates between anatomic total shoulder arthroplasty (ATSA) and reverse total shoulder arthroplasty (RTSA). Methods: Articles published between 2011 and 2025 were selected through PubMed and the Australian Joint Replacement Registry reports from 2023 and 2024. The included studies comprised randomized controlled trials, systematic reviews, and meta-analyses involving adult patients treated for primary osteoarthritis, proximal humerus fractures, and massive irreparable rotator cuff tears. Results: ATSA remains the preferred option in younger patients with an intact rotator cuff, due to superior outcomes in mobility and prosthesis longevity. However, glenoid component loosening remains a significant limitation. Initially reserved for irreparable cuff tears and complex fractures, RTSA has seen a progressive expansion of its indications, offering lower revision rates and satisfactory functional results, particularly in elderly patients. Recent prosthetic innovations include stemless implants, augmented glenoid components, and convertible platforms. Conclusions: The choice between ATSA and RTSA should be individualized, based on patient-specific factors such as age, rotator cuff integrity, functional demands, and bone quality. Advances in implant materials and design, together with improved patient selection, have significantly enhanced clinical outcomes. Full article

Background and Objectives: Reverse shoulder arthroplasty (RSA) is an effective surgical procedure for treating end-stage rotator cuff arthropathy, but it is burdened by a relatively high complication rate, mainly due to glenoid component failure. Preoperative planning and intraoperative navigation based on three-dimensional computed tomography (3D CT) scans have proven to be efficient tools for improving the accuracy and stability of the glenoid component. However, this technology is still developing, and there is currently little available research on the subject, especially where clinical outcomes are concerned. The purpose of this retrospective observational study is to report the radiographic and clinical outcomes of a consecutive series of patients that underwent RSA with the use of these new technologies, compared to a standard procedure. Materials and Methods: A consecutive series of 80 patients underwent RSA for shoulder osteoarthritis by a single surgeon at a single institution with a mean follow-up of 41.9 ± 23.6 months (range 24–108) and were divided into two groups according to the surgical technique employed (conventional or navigated surgery), and they were clinically and radiographically assessed at 1, 3, 6, and 12 months after surgery, and then annually. Results: No statistically significant differences were highlighted among the two groups according to complication rate, radiographical glenoid notching, and clinical outcomes. However, a statistically significant difference was observed in screw number and length and surgical time. In the navigated group, fewer screws with longer lengths had been implanted, with a longer surgical time. Conclusions: The use of 3D CT-based preoperative planning and intraoperative navigation is a safe procedure and produces comparable results with respect to standard instrumentation, without an increased risk of complications. It allowed to achieve higher stability of the implant, saving bone stock due to the use of fewer and longer screws than in a conventional procedure. This could also eventually result in a higher longevity of the implant itself. Full article

Shoulder arthroplasty, including total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA), is a well-established procedure for treating degenerative, post-traumatic, and inflammatory conditions of the shoulder joint. The success of these surgeries depends largely on the precise placement of implants, which helps restore proper joint mechanics, reduce complications, and extend the lifespan of the prosthesis. However, achieving accurate implant positioning can be challenging, especially in cases involving severe bone loss, anatomical deformities, or prior surgeries. Poor alignment can lead to instability, implant loosening, and the need for revision surgery. Computer-assisted navigation has become an important tool in shoulder arthroplasty, providing real-time intraoperative guidance to improve surgical accuracy and consistency. By integrating preoperative 3D imaging with intraoperative tracking, navigation technology allows surgeons to optimize glenoid component placement, reducing the risk of malalignment and mechanical failure. Research suggests that navigation-assisted techniques improve precision, enhance functional outcomes, and may even reduce complication rates by optimizing fixation strategies, such as using fewer but longer screws in RSA. Despite its benefits, navigation in shoulder arthroplasty is not without challenges. It requires additional surgical time, increases costs, and demands a learning curve for surgeons. However, with advancements in artificial intelligence, augmented reality, and robotic-assisted surgery, navigation is expected to become even more effective and accessible. This review explores the current impact of navigation on clinical outcomes, its role in complex cases, and the future potential of this technology. While early results are promising, further long-term studies are needed to fully assess its value and establish best practices for its routine use in shoulder arthroplasty. Full article

Background/Objectives: Rotator cuff tears are a prevalent cause of shoulder pain and functional impairment. Full-thickness tears often require surgical intervention, but managing such injuries can be challenging, particularly when complete anatomical repair is unattainable. Bioinductive implants have emerged as an innovative adjunct to enhance tendon healing and regeneration. Methods: This case report details the partial repair of a full-thickness rotator cuff tear in a 66-year-old woman, augmented with a bioinductive implant. Postoperative recovery was monitored through clinical examinations, MRI, and kinematic analysis at 3 and 6 months. Results: The findings suggest that bioinductive implants may offer a promising strategy for managing complex rotator cuff tears, particularly when complete repair is not feasible. The patient reported improvement in function and pain reduction. Conclusions: The use of bioinductive implants showed promising results, promoting tendon regeneration and improving functional outcomes. Future research should explore patient selection criteria and the long-term effectiveness of this strategy. Full article

Background and Objectives: Shoulder pain, mainly involving rotator cuff tears, is a common type of musculoskeletal pain that significantly impairs quality of life. Arthroscopic rotator cuff repair has become the gold standard for treating symptomatic, full-thickness rotator cuff tears. Double-row repair techniques are widely used because of their superior fixation and healing results. However, fewer implants may reduce treatment costs and raise questions about the impact on clinical outcomes and re-tear rates. This study compares the functional outcomes and re-tear rates of two transosseous-like double-row repair techniques: one anchor and one push lock (Group 1), and two anchors and two push locks (Group 2). Materials and Methods: A prospective, randomized, single-blind study was conducted on 53 patients undergoing arthroscopic repair for crescent-shaped rotator cuff tears (3–5 cm). Before surgery and 24 months after surgery, patients were evaluated for shoulder function using Constant–Murley scores and shoulder abduction angles. MRI was used to assess re-tear rates. Results: Both groups showed significant postoperative improvement in Constant scores (Group 1: 84.1; Group 2: 84.0; p > 0.05). Re-tear rates were slightly higher in Group 1 (23.1%) than in Group 2 (18.5%), but this was not statistically significant (p > 0.05). Shoulder abduction angles improved similarly between groups, with no significant difference in outcome. Despite higher costs and longer operative times, the two-anchor technique provided more stable fixation, but its functional outcomes were comparable to the single-anchor method. Conclusions: Using fewer implants in a double-row repair provides comparable functional outcomes and re-tear rates, and offers surgeons a cost-effective alternative, especially at the beginning of their learning curve. However, the two-anchor technique may be more beneficial in cases requiring improved mechanical stability. These findings provide valuable information to balance cost and effectiveness in rotator cuff repair. Full article

Trapeziometacarpal joint osteoarthritis (TMJ OA) is a progressive condition, particularly affecting postmenopausal women. Various surgical techniques have been proposed, but the optimal approach remains debated. This clinical study compares the clinical, functional, and radiological outcomes of two surgical treatments: suspension tenoplasty using the flexor carpi radialis tendon (Altissimi technique, AST) and a dual-mobility prosthesis. The main complications associated with these procedures include postoperative pain, De Quervain’s syndrome, radial nerve injuries, and prosthetic component mobilization. In prosthetic arthroplasty, the most common complication is component mobilization (8%), while in tenoplasty, postoperative pain is the most frequent (15%). A total of 36 patients were randomized into two groups: 18 patients underwent AST (Group A), and 18 received trapeziometacarpal joint arthroplasty (Group B). Functional outcomes were assessed using the Disabilities of the Arm, Shoulder and Hand (DASH), Visual Analogue Score (VAS), and Michigan Hand Outcomes Questionnaire (MHQ) at 3, 6, 12, and 24 months. Range of motion (ROM), Kapandji score, pulp pinch strength, hand grip strength (Jamar dynamometer), and radiological maintenance of the trapezial space (step-off measurement) were also evaluated. Both procedures resulted in significant pain reduction (VAS, p < 0.05) and functional improvement (DASH, MHQ, p < 0.05). ROM increased significantly in both groups. The Kapandji scores improved from 4.0 ± 1.1 to 9.2 ± 1.2 (Group A) and 4.3 ± 0.8 to 7.8 ± 1.4 (Group B) (p < 0.05). Group B grip strength results showed a greater increase in hand grip strength than Group A (p = 0.23). The radiographic step-off showed slight proximal migration of the first metacarpal in Group A, whereas Group B maintained joint height. No implant loosening or major complications were reported in either group. Both suspension tenoplasty and dual-mobility arthroplasty are effective in TMJ OA. AST ensures joint stability with minimal radiographic changes, whereas TJA provides superior grip strength and ROM recovery. The absence of major complications suggests that TJA is a safe alternative to AST, but its higher cost and potential for implant-related complications must be considered. Full article

Background: Reverse shoulder arthroplasty (RSA) improves shoulder function in cases of glenohumeral osteoarthritis and rotator cuff arthropathy. The design of the glenosphere influences mobility and scapular impingement. This study evaluates the impact of joint volume on the range of motion (RoM) and identifies design modifications to enhance mobility while reducing the impingement risk. Methods: Thirty-four cadaveric shoulders were implanted with the Aequalis Reversed II^® prosthesis in seven configurations: four with 36 mm spheres (centered, 2 mm eccentric, and lateralized by 5 mm and 7 mm) and three with 42 mm spheres (centered, and lateralized by 7 mm and 10 mm). The joint volumes (inferior, anteroinferior, and posteroinferior) were measured via 3D CT scans. The RoM in adduction and elbow-at-side rotations (IR1 and ER1) was recorded. A statistical analysis identified threshold joint volumes correlating with improved mobility. Results: Larger joint volumes correlated with enhanced mobility. The 42 mm spheres demonstrated better adduction and ER1 compared to those of the 36 mm spheres (p < 0.0001). An inferior volume > 5000 mm³ and anteroinferior/posteroinferior volumes >2500 mm³ were thresholds for significant mobility improvement. Lateralization (≥7 mm) or inferior eccentricity (2 mm) improved the mobility with the 36 mm spheres, with the 36 + 2 configuration offering a practical balance for smaller patients. Conclusions: Increased joint volume enhances mobility, particularly in adduction and elbow-at-side rotations. A sphere with a 2 mm inferior offset or a 42 sphere with 7 mm lateralization optimizes the RoM while minimizing impingement risks. Patient-specific considerations, including anatomy and soft tissue tension, remain essential for optimal prosthesis selection. Full article