Shoulder Replacement Research Articles

Readability of English and Spanish online patient education materials for shoulder arthroplasty

BackgroundOnline patient educational materials (OPEMs) are a vital source of information for those undergoing shoulder arthroplasty, though their utility is limited by patient health literacy as the average American reads at an eighth-grade level. To promote optimal reading comprehension, the American Medical Association and National Institutes of Health recommend that OPEMs be written at or below a sixth-grade level. The purpose of this study is to analyze the readability of English and Spanish shoulder arthroplasty OPEMs. MethodsGoogle Search was used to identify the first 25 eligible Shoulder Arthroplasty OPEMs in both English and Spanish using the search terms “shoulder replacement” and “reemplazo de hombro.” Readability of the English OPEMs was calculated using the Flesch-Kincaid Grade Level, Flesch Reading Ease Index (FRE), Flesch Reading Ease Grade Level, Gunning-Fog Index, Coleman-Liau Index, and Simple Measure of Gobbledygook Index. The readability of Spanish OPEMs was calculated using the Fernandez-Huerta Index (FHI; the Spanish version of FRE), Fernandez-Huerta Index Grade Level, Gutiérrez de Polini's Fórmula de compresibilidad, and Índice Flesch-Szigriszt. ResultsThe mean FHI of Spanish OPEMs was significantly higher than the mean FRE of English OPEMs (60.09 vs. 51.48). As such, Spanish OPEMs were written at a significantly lower grade level than English OPEMs (9.70 vs. 11.53). There was not an English or Spanish OPEM that was written at or below a sixth-grade reading level. 4% of Spanish OPEMs and 4% of English OPEMs were written below an eighth-grade reading level. 52% of Spanish OPEMs and 8% of English OPEMs were written between an eighth- and ninth-grade reading level. The designation of OPEMs as being Very Easy/Easy, Standard/Normal, Fairly/Somewhat Difficult, or Difficult/Very Difficult was significantly dependent on whether the OPEM was written in English or Spanish. Discussion and conclusionEnglish shoulder arthroplasty OPEMs were written at a higher reading difficulty than Spanish OPEMs. However, neither English nor Spanish OPEMs were written at a reading level at or below the recommended sixth-grade reading level. As older adults and those in the United States with limited English proficiency are susceptible to low health literacy, OPEMs must be written at an accessible reading level for all. Addressing these disparities in OPEM readability will improve patient care and understanding of shoulder arthroplasty and other orthopedic procedures.

Factors influencing surgical outcomes of fixation with locking plate for three- and four-part proximal humerus fractures in patients aged 50 ​Years and older

BackgroundTreating complex three- and four-part proximal humerus fractures, especially in the elderly, remains contentious, with internal fixation using locking plates and shoulder arthroplasty being primary options. Although proximal humerus locking plates are more commonly used than shoulder replacements, they have a high complication rate. Factors like low bone density, advanced age, multiple fragment fractures, and medial cortical support loss negatively impact treatment outcomes. This study evaluates the functional and radiographic outcomes of using locking plates for treating these fractures in patients aged 50 and older, and the factors influencing outcomes and complication rates at the Ho Chi Minh City Hospital for Trauma and Orthopedics. MethodA descriptive case series study was conducted on 58 patients aged 50 and older (15 males, 43 females) with three- and four-part proximal humerus fractures. These patients underwent open reduction and internal fixation with Locking – compression plate (LCP) periarticular proximal humerus plates at the Ho Chi Minh City Hospital for Traumatology and Orthopedics (HTO) from April 2020 to April 2022. The minimum postoperative follow-up period was 12 months. ResultsThe average age of the patients was 62.78 ​± ​7.73 years, with a mean follow-up of 26.24 ​± ​5.93 months. Among them, 41 had three-part fractures (70.68 ​%) and 17 had four-part fractures (29.32 ​%). At the final follow-up (≥12 months), the mean Constant-Murley score was 70.81 ​± ​9.15, and the mean QDASH score was 8.33 ​± ​2.77. Complications occurred in 6 cases (10.34 ​%). Complex fractures, such as four-part fractures with displacement greater than 2 ​mm, had lower Constant-Murley scores and higher QDASH scores (p ​< ​0.05). Age, gender, bone density by deltoid tuberosity index (DTI), bone grafting, and rotator cuff sutures showed similar trends, but the differences were not statistically significant. ConclusionOpen reduction and internal fixation (ORIF) provides good bone healing and functional outcomes for three- and four-part proximal humerus fractures. Factors such as age, gender, bone density, bone grafting, and rotator cuff sutures do not significantly affect outcomes. Therefore, osteoporosis should not be a contraindication for ORIF with locking plates in these cases. Complex fractures, however, often lead to poorer outcomes and higher complication rates post-surgery.

Effectiveness over time of the reverse shoulder prosthesis for acute proximal humeral fracture

Reverse shoulder arthroplasty (RSA) has proven to be an effective surgical procedure for irreparable rotator cuff tears, comminuted fractures of the proximal humerus and shoulder arthroplasty revision surgeries. We know from the literature that the functional results are good in the short term, but not whether these results remain stable in the long term or, on the contrary, show a deterioration in functionality. This study aims to analyze the functionality, degree of satisfaction, complications, and prosthesis survival at different cut-off points in patients with complex proximal humerus fractures treated with RSA, with a minimum postoperative follow-up of 7 years. Analytical, longitudinal and prospective observational study of a cohort of patients treated for a fracture of the proximal humerus with PIH. Functional outcome was assessed using the Constant scale and the Constant adjusted for age and gender of the patients. Quality of life was measured using the University of California at Los Angeles Shoulder Assessment scale (UCLA) and the Disability of the Arm, Shoulder and Hand score scale (QuickDASH). In addition, range of motion, pain and radiological variables of loosening, scapular notching and tuberosity consolidation were assessed. Thirty-three patients were included with a mean postoperative follow-up of 8.3 years (range 7-12 years). There was a progressive and significant decrease in Constant score at 5and7years follow-up compared to the baseline assessment 2 years after surgery, although the effect size was not significant. The age- and sex-adjusted Constant as well as the UCLA scale did not show statistically significant variations at follow-up. Both shoulder abduction and anterior shoulder flexion correlated well with the final QuickDASH score. Radiological variables did not influence any of the study outcome variables. The functionality and quality of life of patients with complex proximal humerus fractures treated with RSA decreased significantly compared to the 2-year evaluation, although this change was not clinically relevant. Survival of RSA was satisfactory in the medium to long term with a low complication rate.

Internal rotation-based activities of daily living show limitations following reverse shoulder arthroplasty versus anatomic shoulder arthroplasty

BackgroundOne of the more common limitations after reverse total shoulder arthroplasty (rTSA) is limited internal rotation (IR). Outcomes after rTSA are commonly reported as patient-reported outcome measures (PROMs) but are rarely assessed by specific activities of daily living (ADLs). Analyzing ADLs evaluates for specific motions from PROMs. The purpose of this study is to investigate the deficit in IR following rTSA through ADLs. MethodsA retrospective case-control study was conducted using institutional medical records. Patients who underwent total shoulder arthroplasty between 2009 and 2020 were reviewed for demographic and clinical variables (type of arthroplasty, indication, range of motion and strength). PROMs were taken by phone at 2-year minimum follow-up. Statistics were calculated as two-tailed using Chi-square or simple t-tests as appropriate. ResultsAmong 208 patients, 114 aTSA, and 94 rTSA were identified and included in this study. Both groups reported significant increases in range of motion and strength postoperatively. PROMs were mostly similar between aTSA and rTSA (Single Assessment Numeric Evaluation 83.4 ± 17.1 vs. 82.3 ± 18.4, P = .643; visual analog scale Pain 2.2 ± 2.8 vs. 1.8 ± 2.4, P = .247), while Simple Shoulder Test did show a difference (9.2 ± 2.8 vs. 7.8 ± 3.2, P = .001) with higher scores in the aTSA cohort. The ADLs which showed significant disparity between aTSA and rTSA were toileting (P = .001), donning a coat (P = .017), reaching one’s back (P = .017), as well as throwing overhand (0.013) with rTSA patients reporting more difficulty in all these ADLs. ConclusionBoth aTSA and rTSA are safe and efficacious options for shoulder replacement, as evidenced by high Single Assessment Numeric Evaluation and low visual analog scale pain scores and should be used according to their established indications. Surgeons may counsel rTSA patients about potential increased deficits in ADLs reliant on IR such as managing toileting and dressing compared to aTSA recipients.

High in-hospital preoperative anxiety levels are not associated with an increased length of stay or readmission following primary shoulder arthroplasty

BackgroundAnxiety is prevalent in our society, affecting all facets of patients’ lives. There is, however, a paucity of literature exploring how anxiety extends into the orthopedic perioperative setting. We sought to analyze a subset of patients undergoing primary shoulder arthroplasty to determine whether correlations exist between anxiety, patient characteristics, time spent in the hospital, and likelihood of returning to the hospital after discharge. MethodsAfter obtaining institutional review board approval, our hospital prospectively identified and approached all patients undergoing total shoulder arthroplasty between February and June of 2023. Patients completed the Visual Analog Scale for Anxiety (VAS-A) and Amsterdam Preoperative Anxiety and Information Scale (APAIS), two validated tools used to assess preoperative anxiety levels and need for information, in the preoperative holding area before surgery. Patient demographics, hospital length of stay (LOS), and 30-day readmission rate were collected and analyzed. ResultsA total of 79 patients were enrolled. Nineteen percent of patients were found to be anxious using the APAIS tool, while 37.7% of patients were found to be anxious using the VAS-A tool. No significant correlation was found between APAIS or VAS-A anxiety scoring and hospital LOS. No significant correlation was found between APAIS or VAS-A anxiety scoring and 30-day readmission rate. A significant correlation was found between APAIS anxiety scoring and body mass index (BMI), as well as VAS-A scoring and BMI. However, no significant correlation was found between BMI and hospital LOS or between BMI and 30-day readmission rate. ConclusionOur study did not find a statistically significant correlation between immediate preoperative anxiety levels in patients undergoing shoulder arthroplasty and their length of stay or 30-day readmission rate. We did discover a linear relationship between patient BMI and their preoperative anxiety scores; however, no significant direct correlation was found between a patient’s BMI and their length of stay or their 30-day readmission rate. Our findings suggest that higher levels of preoperative anxiety should not preclude a patient from the benefits of consideration of early discharge planning such as same-day total shoulder replacement.

Superior functional outcome following reverse shoulder arthroplasty compared to hemiarthroplasty for displaced three- and four-part fractures in patients 65 and older: results from a prospective multicenter randomized controlled trial - The shoulder hemiarthroplasty or reverse polarity arthoplasty (SHeRPA) trial

BackgroundAcute unreconstructible 3- or 4-part proximal humerus fractures can be treated with hemiarthroplasty or reverse polarity shoulder arthroplasty. Randomized trials using implants from multiple different companies or uncemented implants have found superior results with reverse polarity arthroplasty. AimsThis study aims to determine whether cemented reverse polarity arthroplasty produces a superior outcome compared to cemented hemiarthroplasty using one implant system in patients aged 65 years and over at 12 months follow-up as measured with the Constant score. MethodsA prospective patient and assessor blinded multicenter randomized controlled trial was conducted of shoulder hemiarthroplasty or reverse polarity arthroplasty in patients aged 65 years and older with acute 3- and 4-part proximal humerus fracture not amenable to osteosynthesis. The primary outcome was the Constant score at 12 months with total follow-up to 24 months. Block randomization by site was undertaken using random number generation and sealed envelopes. Power analysis indicated that 17 patients were required in each arm to achieve 80% power with an alpha-value of 5%. Secondary outcome measures were the difference in the mean Constant Score, Quick Disabilities of the Arm Shoulder and Hand Questionnaire (QuickDASH), Oxford Shoulder Score (OSS), American Shoulder and Elbow Surgeons (ASES) Score and EQ5D-5L up to two years; differences in complication rate at one and two years; differences in revision and implant failure at one and two years. Results18 patients were randomized to hemiarthroplasty and 18 to reverse polarity arthroplasty across 4 sites. The primary outcome as measured by the Constant score at 12 months was better in the reverse polarity shoulder arthroplasty (RSA) group (Mean 51.1, s.d. 14.9) compared to the hemiarthroplasty (HA) group (mean 35.0, s.d. 13.5) (p=0.004). No significant difference was reported at 24 months but this may be due to high rates of attrition (22%). The mean EQ-5D-5L patient rated health status score was significantly higher in the RSA group compared to the HA group at 12 months. One hemiarthroplasty was revised due to implant uncoupling and one reverse polarity shoulder replacement was revised due to instability. No other complications were recorded. DiscussionTreatment of unreconstructible 3- or 4-part proximal humerus fractures with reverse polarity shoulder arthroplasty results in a superior outcome compared to shoulder hemiarthroplasty at 12 months measured with the Constant score with no increased risk of failure up to 24 months in patients age 65 years and over. High attrition rates are observed in this older population due to cognitive decline and death from other causes.

Advancing predictive accuracy for shoulder replacement surgery

Advancing predictive accuracy for shoulder replacement surgery

Bone Density Changes at the Origin of the Deltoid Muscle following Reverse Shoulder Arthroplasty.

Background: Reverse total shoulder arthroplasty (RSA) significantly impacts deltoid length, tension, and structure. Studies have extensively investigated various modifications in deltoid characteristics, such as perfusion, elasticity, caliber, histological changes, and strength post-RSA. However, to date, there is a notable absence of research evaluating changes in bone mineral density (BMD) at the deltoid muscle origin after the RSA procedure. Methods: A retrospective analysis of a consecutive series of RSAs performed between May 2011 and May 2022 was conducted. Inclusion criteria comprised primary RSAs with both preoperative and last follow-up shoulder CT scans and a minimum follow-up of 12 months. Trabecular attenuation measured in Hounsfield units (HU) was calculated using a rapid region-of-interest (ROI) method. BMD analysis involved segmenting three ROIs in both pre- and postoperative CT scans of each patient: the acromion, clavicle, and spine of the scapula. Results: A total of 44 RSAs in 43 patients, comprising 29 women and 14 men, were included in this study. The mean follow-up duration was 49 ± 22.64 months. Significant differences were observed between preoperative and postoperative HU values in all analyzed regions. Specifically, BMD increased in the acromion and spine, while it decreased in the clavicle (p-values 0.0019, <0.0001, and 0.0088, respectively). Conclusions: The modifications in shoulder biomechanics and, consequently, deltoid tension post-implantation result in discernible variations in bone quality within the analyzed regions. This study underscores the importance of thorough preoperative patient planning. By utilizing CT images routinely obtained before reverse shoulder replacement surgery, patients at high risk for fractures of the acromion, clavicle, and scapular spine can be identified.

Design and evaluation of a symmetric amplification mechanism based anthropomorphic shoulder

Shoulder joints determine the motion range of the upper limb. Thus, the compact and well-stiffened spherical parallel mechanism (SPM) has emerged as the mainstream shoulder prosthesis design approaches. However, the SPM’s moving pairs of redundant motions impose excessive constraints that limit its workspace. Therefore, amplifying the workspace of the SPM to cover the motion range required by human daily activities is a pressing problem in shoulder prosthesis design. To address this challenge, this study proposed a workspace amplification approach through the kinematic analysis of a symmetrically arranged 2 degrees of freedom (DoFs) passive mechanism, together with the designed and optimized 3-RRR SPM, to construct an anthropomorphic shoulder. The effectiveness and reliability of the proposed mechanism was verified through thorough analyses. Simulation and experiment results demonstrated that the workspace amplification mechanism could significantly increase the maximum motion match index between the shoulder prosthesis and the daily workspace of the human shoulder from only 26.3% to 94.79%, solving the problem that the traditional SPM-based prostheses cannot satisfy the motion range required by daily activities. Moreover, the proposed mechanism has the potential to amplify the workspace of most parallel mechanisms with multiple DoFs after proper modification.

International trends in shoulder replacement: a meta-analysis from 11 public joint registers.

International variation exists in the types of shoulder replacement used for treatment of specific diseases. Implant choice continues to evolve without high-quality evidence. Our aim was to evaluate trends in incidence rates of shoulder replacement and assess any recent changes in practice between countries by using registry data. Patient characteristics, indication and year of surgery, type of replacement, and collection methods of patient-reported outcomes (PROMs) was extracted from 11 public joint registries. Meta-analyses examined use of reverse total shoulder replacement (RTSR) for osteoarthritis, cuff tear arthropathy, and acute fracture; use of anatomical total shoulder replacement (TSR) for osteoarthritis; and use of humeral hemiarthroplasty for fracture. The annual growth rate of shoulder replacements performed is 6-15% (2011-2019). The use of RTSR has almost doubled (93%). RTSR is now universally performed for cuff tear arthropathy (97.3%, 95% confidence interval [CI] 96.0-98.1). Its use for avascular necrosis, trauma, and inflammatory arthropathy is increasing. The use of RTSR was similar (43.1%, CI 30.0-57.2) versus TSR (44.7%, CI 31.1-59.1) for osteoarthritis. The types of PROMs used, collection time points, and response rates lack standardization. COVID-19 had a varying inter-registry impact on incidence rates. The incidence of shoulder replacements has grown. Use of RTSR has increased for all disease indications despite limited high-quality evidence driving this change in indications outside of cuff arthropathy. Consequently, less variation is observed in international practice. Existing differences now relate to use of newer implant types and methodology of PROMs collection, which prevents international comparison and outcome analysis.

Challenges and Outcomes in the Management of Periprosthetic Humeral Fractures: A Retrospective Study and Review of Current Approaches.

Periprosthetic humeral fractures are a rare and increasing entity due to the rising number of shoulder arthroplasties. These fractures pose a significant challenge for surgeons, with incidence rates ranging from 1.2% to 19.4%. They can occur intraoperatively or as late complications, often influenced by trauma, prosthetic wear, or loosening. A retrospective study was conducted on all patients admitted with periprosthetic humeral fractures over a four-year period (2018-2022). Inclusion criteria were postoperative periprosthetic humeral fractures with a minimum follow-up of six months. Exclusion criteria included intraoperative fractures, fractures of the glenoid or coracoid process, and cases with follow-up of less than six months or incomplete data. The study included six patients with an average age of 83.1 years, predominantly female (four females andtwo males). All fractures occurred postoperatively: four on reverse shoulder prostheses, one on an anatomical prosthesis, and one on a hemiarthroplasty. The mechanism was low-energy trauma, with fractures occurring an average of 96 months post-initial surgery. Fractures were classified using the Campbell system: three in region 4, two in region 3, and one in region 2. Radiographs showed four cemented and two uncemented stems. Three patients underwent surgical treatment with either prosthetic replacement using a long stem and fracture cerclage or lockingcompression plate (LCP). The remaining three patients were treated conservatively with a Sarmiento brace due to advanced age, bone fragility, low functional demand, and comorbidities. Radial nerve palsy was a complication in two patients post-trauma, with one recovering fully and the other not recovering before death due to associated complications. All fractures consolidated within an average of seven months (range: 5-8 months).Functional recovery was satisfactory with a median Constant-Murley Shoulder Score of 69in surgically treated patients, with range of motion between 100 and 140 degrees. Only two conservatively treated patients achieved fracture consolidation, and functional recovery was inadequate. Managing periprosthetic humeral fractures remains challenging. Treatment goals include fracture healing, maintaining prosthetic stem stability, preserving glenohumeral motion, and restoring shoulder function. Despite various classification systems, the literature shows limited and variable data on incidence and treatment outcomes. Conservative treatment may be considered for stable implants and acceptable alignment, but surgical intervention is often necessary for displaced fractures or implant loosening. The management of periprosthetic humeral fractures requires a tailored, multidisciplinary approach to optimize outcomes and improve patient quality of life. With the increasing incidence of these fractures due to the growing use of shoulder arthroplasty, ongoing research and development of new techniques and therapeutic strategies are essential to address this clinical challenge effectively.

“In My Experience…Medical Device Design &amp; Innovation in Shoulder Replacements”

The author reviews his experience with a novel process of designing and bringing a medical device to market.

The predictive value and reliability of ultrasound-guided synovial aspiration and biopsies for diagnosing periprosthetic shoulder infections.

Preoperative diagnosis of periprosthetic shoulder infections (PSI) is difficult. Infections are mostly caused by low virulence bacteria and patients do not show typical signs of infection. The aim of this study was to determine the diagnostic value and reliability of ultrasound-guided biopsies for cultures alone and in combination with multiplex polymerase chain reaction (mPCR), serum markers, and/or synovial markers for the preoperative diagnosis of PSI in patients undergoing revision shoulder surgery. A prospective explorative diagnostic cohort study was performed including 55 patients undergoing revision shoulder replacement surgery. A shoulder puncture was performed preoperatively before incision to collect synovial fluid for mPCR analysis and for measurement of interleukin-6, calprotectin, white blood cell count (WBC), and polymorphonuclear cells. Also prior to revision surgery, six ultrasound-guided synovial tissue biopsies were collected for culture and two for mPCR analysis. A blood sample was obtained to determine serum C-reactive protein, WBC, and erythrocyte sedimentation rate. Six routine care tissue biopsies were taken during revision surgery and served as reference standard. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV; the primary outcome measure), and accuracy were calculated for ultrasound-guided biopsies, blood and synovial markers, mPCR, and combinations thereof. Routine tissue cultures were positive for infection in 24 patients. Cultures from ultrasound-guided biopsies diagnosed infection in 7 of these patients, yielding a sensitivity, specificity, PPV, NPV, and accuracy of 29.2%, 93.5%, 77.8%, 63.0%, and 65.6%, respectively. The best diagnostic value was found for the combination of ultrasound-guided biopsies for culture, synovial WBC, and calprotectin with a sensitivity of 69.2%, specificity of 80.0%, PPV of 69.2%, and NPV of 80.0%. Ultrasound-guided biopsies for cultures alone and in combination with mPCR, and/or blood and/or synovial markers are not reliable enough to use in clinical practice for the preoperative diagnosis of PSI. Diagnostic study level II.

Reticular Telangiectatic Erythema in Association to Implanted Medical Device

Infections associated with implantable devices pose significant risks, as bacteria and other microorganisms can attach to the device surfaces, leading to complications ranging from mild inflammation to severe, potentially fatal infections. This review explores the development of reticular telangiectatic erythema (RTE) in patients with various implanted medical devices, including subcutaneous neurostimulators, shoulder prostheses, and hip prostheses. RTE manifests as red, net-like patches on the skin covering the device and is often associated with low-grade infections caused predominantly by Staphylococcus epidermidis, known for its biofilm-forming capability. The review presents three cases of RTE following device implantation, all resolving after antimicrobial treatment and device removal, despite negative patch tests for contact allergies. These cases highlight the importance of recognizing low-grade infections in patients with implanted devices and underscore the need for precise diagnostic and therapeutic strategies. The findings suggest that infections involving S. epidermidis play a critical role in the development of RTE. This review stresses the importance of preventive measures such as meticulous implantation techniques and prophylactic antibiotics and advocates for further research with larger sample sizes to better understand the role of microorganisms in RTE. It also calls for the development of improved diagnostic and treatment strategies. Future research directions include creating new materials resistant to biofilm formation, developing advanced antimicrobial agents, and enhancing diagnostic techniques to detect infections earlier.

Do patients with osteoarthritis lose weight prior to elective joint replacement?

Obesity is a known risk factor for the development of osteoarthritis and the subsequent need for joint replacement. Weight loss has been shown to reduce pain, disability, and the need for joint replacement, particularly in patients with knee osteoarthritis. The aim of this study was to investigate pre-operative weight change in patients with hip, knee, and shoulder osteoarthritis at a regional, public hospital in Australia, to identify opportunities for pre-operative weight-loss intervention. A retrospective review of patients who underwent elective primary total hip (THR), knee (TKR), and shoulder (TSR) replacement for osteoarthritis was conducted between December 2019 and December 2022. BMI data were collected at three time points: (1) general practitioner (GP) referral; (2) orthopaedic clinic review; and (3) pre-admission clinic (PAC) assessment. A total of 496 patients were included in the study, of which 205 underwent THR, 251 underwent TKR, and 40 underwent TSR. The mean patient age was 67 years, and 46.4% were female. At the time of GP referral, the mean body mass index (BMI) was 31.4 kg/m2. Across the study period, only 2% of patients experienced clinically significant weight loss pre-operatively (≥5% of total body weight). This study has demonstrated that very few patients lose weight prior to undergoing joint replacement in the public sector in Australia. This highlights the need for targeted non-surgical weight loss interventions for patients currently awaiting joint replacement.

A GAN based PID controller for highly adaptive control of a pneumatic-artificial-muscle driven antagonistic joint

Upper limb prostheses are commonly propelled by pneumatic artificial muscles organized in an antagonistic arrangement. Nonetheless, the control of upper limb prostheses under changing/unknown situations is difficult and necessary for a variety of real-world applications. Adaptive control, learning-based control, and robust control have been studied to deal with such challenges. However, their adaptability is insufficient for prostheses used in daily life, which are exposed to variable task levels, user motor characteristics, and prosthetic features. This paper introduces a highly adaptive controller for the first time based on Generative Adversarial Nets and proportional–integral–derivative controller (G-PID controller). G-PID controller comprises a generator for generating compensation actions to enhance PID responsiveness when controlling the unknown/changing system. Moreover, it incorporates a discriminator that receives responses from both a user-preselected reference system and the compensated changing/unknown system, and simultaneously determines the source of these responses. Through continuous updates, the compensator modifies the response of unknown/changing system to align with the reference system, thereby facilitating adaptive control. The G-PID controller’s effectiveness is evaluated through 1-degree of freedom (DoF) joint and 2-DoF shoulder prostheses in simulation experiments, and further validated in prototype experiments focusing on online learning for unknown and time-varying payload. The results demonstrate its ability to deal with diverse types of unknowns/changes, marking a significant advancement towards incorporating prostheses seamlessly into daily life.

Shoulder &amp; Elbow

The June 2024 Shoulder &amp; Elbow Roundup360 looks at: Reverse versus anatomical total shoulder replacement for osteoarthritis? A UK national picture; Acute rehabilitation following traumatic anterior shoulder dislocation (ARTISAN): pragmatic, multicentre, randomized controlled trial; acid for rotator cuff repair: a systematic review and meta-analysis of randomized controlled trials; Metal or ceramic humeral head total shoulder arthroplasty: an analysis of data from the National Joint Registry; Platelet-rich plasma has better results for long-term functional improvement and pain relief for lateral epicondylitis: a systematic review and meta-analysis of randomized controlled trials; Quantitative fatty infiltration and 3D muscle volume after nonoperative treatment of symptomatic rotator cuff tears: a prospective MRI study of 79 patients; Locking plates for non-osteoporotic proximal humeral fractures in the long term; A systematic review of the treatment of primary acromioclavicular joint osteoarthritis.

Shoulder Arthroplasty: A Bibliometric Analysis Using the Scopus Database.

Primary joint replacements are performed increasingly often worldwide, driven by an aging population, improvement in surgical techniques, and advancements in implant designs. While more attention has traditionally been focused on weight-bearing joints such as the hip and knee, shoulder replacement surgeries have gained increasing attention in recent years due to the population's demand for a better quality of life. Thus far, a comprehensive bibliometric analysis of shoulder arthroplasty-related publications using the Scopus database has not yet been conducted. This bibliometric analysis aims to fill this gap by reviewing the Scopus database from its inception until 2023 to examine the literature on shoulder arthroplasty. A total of 5300 publications meeting the selection criteria were included in this analysis. The turn of the century marked a significant turning point for the field of shoulder arthroplasty, with an increasing number of publications produced annually. This trend can be attributed to the improvement of implant designs, which have become more consistent and reliable over time. While the majority of articles were authored by researchers and clinicians from the United States of America (USA), publications by French authors had a higher scholarly impact in the field. There is a noticeable gap in research on shoulder arthroplasty in developing countries, possibly due to the prohibitively high cost of implants and the prioritization of other healthcare sectors. This bibliometric analysis, utilizing Scopus data, serves as a guiding light for researchers, clinicians, and policymakers, potentially fostering collaborative projects and guiding the development of future studies to further advance the field of shoulder arthroplasty, particularly in developing countries.

Unexpected positive cultures of humeral head detected with dithiothreitol in primary shoulder arthroplasty

BackgroundUnexpected positive cultures (UPCs) are frequently observed in primary shoulder arthroplasty and its clinical significance has not yet been well defined. The aim is to evaluate the UPCs in humeral head in primary shoulder replacement and to understand if UPCs increase in patients with risk factors for contamination (previous surgery or infiltrations). MethodsPatients undergoing total shoulder replacement were enrolled in this prospective observational study. To reduce the risk of humeral head contamination, all known procedures to reduce C. acnes burden of the skin were implemented. Patients were divided into 2 groups, namely patients who had undergone previous rotator cuff repair or infiltration and patients with no risk factors for contamination. All the humeral heads harvested were treated with Dithiothreitol, in a specific device (MicroDTTect), to increase the sensitivity of the cultures for bacterial identification. The cultures were analyzed for aerobic and anaerobic bacteria for up to 14 days. ResultsThe UPCs positivity rate of the 80 patients in the study was 19 % (15 patients). The positivity rates for UPCs in the group with and without risk factors were 30 % (12 patients) and 7.5% (3 patients), respectively. The rate of positive culture was higher in men (87%) than in women (13%).The observed positivity was due to Cutibacterium acnes and peptoniphilus asaccarolyticus, both slow-growing anaerobes. ConclusionsPatients with previous surgery or infiltrations had a 4-fold higher rate of positivity for UPCs compared with patients without previous risk factors. The higher percentage of positivity in patients with risk factors could be related to changes in the joint microenvironment after shoulder procedures. We do not know whether the presence of UPCs could be associated with the development of periprosthetic infections at longer follow-up.

Imaging in shoulder arthroplasty: Current applications and future perspectives

Shoulder arthroplasty has become a standard surgical procedure for treating a variety of complex shoulder disorders, including those with degenerative and traumatic aetiologies. The ever-improving success rates of shoulder arthroplasty could be attributed to advancements in endoprosthesis design, improvements in the biomechanics of endoprosthetic components, and improvements in surgical techniques. It improves patient outcomes and helps restore shoulder joint function and mobility.Imaging plays a vital role by enabling surgeons to plan arthroplasty procedures, help guide endoprosthesis placement, and monitor postoperative outcomes. In addition, imaging plays a role in assessing the residual bone stock and status of rotator cuff integrity and in correcting the placement of prosthetic components to restore shoulder mobility.CT-guided navigation aids surgeons by helping them choose appropriate components for implants and ensuring that implants are placed optimally during surgery. It can lead to better surgical results with reduced patient morbidity and a longer duration of prosthetic stability. After surgery, it is crucial to use imaging techniques to detect issues such as periprosthetic loosening, infections, or fractures to start effective management strategies to enhance patient recovery.This article aims to provide orthopaedic surgeons and radiologists with knowledge on the imaging methods used in shoulder arthroplasty and their role in presurgical planning, intraoperative guidance and postoperative assessment. In this study, we aimed to investigate the rationale behind utilising various types of shoulder replacements: total shoulder replacement (TSA), reverse total shoulder arthroplasty (RTSA), and hemiarthroplasty; methods, their respective advantages and limitations; and outcomes. Our objective is to comprehensively analyse the procedures mentioned above and highlight their unique features and benefits to facilitate a better understanding of these approaches. Additionally, we will discuss how these imaging techniques help identify issues such as loose components, fractures around the implant site, joint instability and infections.