Ultrasound-guided determination demonstrates influence of age, sex and type of sport on medial femoral condyle cartilage thickness in children and adolescents.

PURPOSE: To analyse the reliability of ultrasound-guided measurement of the cartilage thickness at the medial femoral condyle in athletically active children and adolescents before and after mechanical load in relation to age, sex and type of sport. METHODS: Three successive measurements were performed in 157 participants (median/min-max age: 13.1/6.0-18.0 years, 106 males) before and after mechanical load by squats at the same site of the medial femoral condyle by defined transducer positioning. Test-retest reliability was examined using Cronbach's α $\alpha $ calculation. Differences in cartilage thickness were analysed with respect to age, sex and type of practiced sports, respectively. RESULTS: Excellent reliability was achieved both before and after mechanical load by 30 squats with a median cartilage thickness of 1.9 mm (range: 0.5-4.8 mm) before and 1.9 mm (0.4-4.6 mm) after mechanical load. Male cartilages were thicker (p < 0.01) before (median: 2.0 mm) and after (2.0 mm) load when compared to female cartilage (before: 1.6 mm; after: 1.7 mm). Median cartilage thickness was about three times higher in karate athletes (before: 2.3 mm; after: 2.4 mm) than in sports shooters (0.7; 0.7 mm). Cartilage thickness in track and field athletes, handball players and soccer players were found to lay in-between. Sport type related thickness changes after mechanical load were not significant. CONCLUSION: Medial femoral condyle cartilage thickness in childhood correlates with age, sex and practiced type of sports. Ultrasound is a reliable and simple, pain-free approach to evaluate the cartilage thickness in children and adolescents. LEVEL OF EVIDENCE: Level III.

Polytomous Rasch Analyses of Surgeons' Decision-Making on Choice of Procedure in Endoscopic Lumbar Spinal Stenosis Decompression Surgeries.

BACKGROUND: With the growing prevalence of lumbar spinal stenosis, endoscopic surgery, which incorporates techniques such as transforaminal, interlaminar, and unilateral biportal (UBE) endoscopy, is increasingly considered. However, the patient selection criteria are debated among spine surgeons. OBJECTIVE: This study used a polytomous Rasch analysis to evaluate the factors influencing surgeon decision-making in selecting patients for endoscopic surgical treatment of lumbar spinal stenosis. METHODS: A comprehensive survey was distributed to a representative sample of 296 spine surgeons. Questions encompassed various patient-related and clinical factors, and responses were captured on a logit scale graphically displaying person-item maps and category probability curves for each test item. Using a Rasch analysis, the data were subsequently analyzed to determine the latent traits influencing decision-making. RESULTS: The Rasch analysis revealed that surgeons' preferences for transforaminal, interlaminar, and UBE techniques were easily influenced by comfort level and experience with the endoscopic procedure and patient-related factors. Harder-to-agree items included technological aspects, favorable clinical outcomes, and postoperative functional recovery and rehabilitation. Descriptive statistics suggested interlaminar as the best endoscopic spinal stenosis decompression technique. However, logit person-item analysis integral to the Rasch methodology showed highest intensity for transforaminal followed by interlaminar endoscopic lumbar stenosis decompression. The UBE technique was the hardest to agree on with a disordered person-item analysis and thresholds in category probability curve plots. CONCLUSION: Surgeon decision-making in selecting patients for endoscopic surgery for lumbar spinal stenosis is multifaceted. While the framework of clinical guidelines remains paramount, on-the-ground experience-based factors significantly influence surgeons' selection of patients for endoscopic lumbar spinal stenosis surgeries. The Rasch methodology allows for a more granular psychometric evaluation of surgeon decision-making and accounts better for years-long experience that may be lost in standardized clinical guideline development. This new approach to assessing spine surgeons' thought processes may improve the implementation of evidence-based protocol change dictated by technological advances was endorsed by the Interamerican Society for Minimally Invasive Spine Surgery (SICCMI), the International Society for Minimal Intervention in Spinal Surgery (ISMISS), the Mexican Spine Society (AMCICO), the Brazilian Spine Society (SBC), the Society for Minimally Invasive Spine Surgery (SMISS), the Korean Minimally Invasive Spine Society (KOMISS), and the International Society for the Advancement of Spine Surgery (ISASS).

Comparative Analysis of Learning Curve, Complexity, Psychological Stress, and Work Relative Value Units for CPT 62380 Endoscopic Lumbar Spinal Decompression vs Traditional Lumbar Spine Surgeries: A Paired Rasch Survey Study.

BACKGROUND: Effective 1 January 2017, single-level endoscopic lumbar discectomy received a Category I Current Procedural Terminology (CPT) code 62380. However, no work relative value units (RVUs) are currently assigned to the procedure. An international team of endoscopic spine surgeons conducted a study, endorsed by several spine societies, analyzing the learning curve, difficulty, psychological intensity, and estimated work RVUs of endoscopic lumbar spinal decompression compared with other common lumbar spine surgeries. METHODS: A survey comparing CPT 62380 to 10 other comparator CPT codes reflective of common spine surgeries was developed to assess the work RVUs in terms of learning curve, difficulty, psychological intensity, and work effort using a paired Rasch method. RESULTS: The survey was sent to 542 spine specialists. Of 322 respondents, 150 completed the survey for a 43.1% completion rate. Rasch analysis of the submitted responses statistically corroborated common knowledge that the learning curve with lumbar endoscopic spinal surgery is steeper and more complex than with traditional translaminar lumbar decompression surgeries. It also showed that the psychological stress and mental and work effort with the lumbar endoscopic decompression surgery were perceived to be higher by responding spine surgeons compared with posterior comparator decompression and fusion surgeries and even posterior interbody and posterolateral fusion surgeries. The regression analysis of work effort vs procedural difficulty showed the real-world evaluation of the lumbar endoscopic decompression surgery described in CPT code 62380 with a calculated work RVU of 18.2464. CONCLUSION: The Rasch analysis suggested the valuation for the endoscopic lumbar decompression surgery should be higher than for standard lumbar surgeries: 111.1% of the laminectomy with exploration and/or decompression of spinal cord and/or cauda equina (CPT 63005), 118.71% of the laminectomy code (CPT 63047), which includes foraminotomy and facetectomy, 152.1% of the hemilaminectomy code (CPT 63030), and 259.55% of the interlaminar or interspinous process stabilization/distraction without decompression code (CPT 22869). This research methodology was endorsed by the Interamerican Society for Minimally Invasive Spine Surgery (SICCMI), the Mexican Society of Spinal Surgeons (AMCICO), the International Society For Minimally Invasive Spine Surgery (ISMISS), the Brazilian Spine Society (SBC), the Society for Minimally Invasive Spine Surgery (SMISS), the Korean Minimally Invasive Spine Surgery (KOMISS), and the International Society for the Advancement of Spine Surgery (ISASS). CLINICAL RELEVANCE: This study provides an updated reimbursement recommendation for endoscopic spine surgery. LEVEL OF EVIDENCE: Level 3.

Disability-adjusted life years from bone and joint infections associated with antimicrobial resistance: an insight from the 2019 Global Burden of Disease Study.

PURPOSE: Bone and joint infections, complicated by the burgeoning challenge of antimicrobial resistance (AMR), pose significant public health threats by amplifying the disease burden globally. We leveraged results from the 2019 Global Burden of Disease Study (GBD) to explore the impact of AMR attributed to bone and joint infections in terms of disability-adjusted life years (DALYs), elucidating the contemporary status and temporal trends. METHODS: Utilizing GBD 2019 data, we summarized the burden of bone and joint infections attributed to AMR across 195 countries and territories in the 30 years from 1990 to 2019. We review the epidemiology of AMR in terms of age-standardized rates, the estimated DALYs, comprising years of life lost (YLLs) and years lived with disability (YLDs), as well as associations between DALYs and socio-demographic indices. RESULTS: The GBD revealed that DALYs attributed to bone and joint infections associated with AMR have risen discernibly between 1990 and 2019 globally. Significant geographical disparities and a positive correlation with socio-demographic indicators were observed. Staphylococcus aureus infections, Group A Streptococcus, Group B Streptococcus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterobacter-related bone and joint infections were associated with the highest DALYs because of a high proportion of antimicrobial resistance. Countries with limited access to healthcare, suboptimal sanitary conditions, and inconsistent antibiotic stewardship were markedly impacted. CONCLUSIONS: The GBD underscores the escalating burden of bone and joint infections exacerbated by AMR, necessitating urgent, multi-faceted interventions. Strategies to mitigate the progression and impact of AMR should emphasize prudent antimicrobial usage and robust infection prevention and control measures, coupled with advancements in diagnostic and therapeutic modalities.

Both Labral Debridement and Labral Repair Result in >90% Total Hip Arthroplasty-free Survival at 5-Year Follow-Up: An Analysis of the German Cartilage Registry (KnorpelRegister DGOU).

PURPOSE: To compare clinical outcome parameters between labral debridement and repair by analyzing the dataset of a multinational registry. METHODS: The data are based on the hip module of the German Cartilage Registry (KnorpelRegister DGOU). The register included patients designated for cartilage or femoroacetabular impingement surgery (up to July 1, 2021; n = 2725). The assessment consisted of the patient's characteristics, the type of labral treatment, the length of labral therapy, the pathology, the grade of cartilage damage, and the type of performed approach. The clinical outcomes were documented by the international hip outcome tool via an online platform. Separated Kaplan-Meier analyses were used for total hip arthroplasty (THA)-free survival rates. RESULTS: The debridement group (n = 673) showed a mean score increase of 21.9 ± 25.3 points. The repair group (n = 963) had a mean improvement of 21.3 ± 24.6 (P > .05). The 60-month THA-free survival rate was 90% to 93% for both groups (P > .05). A multivariance analysis showed that the grade of cartilage damage was the only independent statistically significant factor (P = .002-.001) influencing patients' outcomes and THA-free survival. CONCLUSIONS: Labral debridement and repair led to good and reliable results. However, these results should not be interpreted with the conclusion that the cheaper and technically easier labral debridement is the recommended treatment due to comparable results in the present study. The clinical outcome and the THA-free survival seemed to be more influenced by the grade of cartilage damage. LEVEL OF EVIDENCE: Level III, retrospective comparative therapeutic trial.

Comparison of the scientific performance in hip and knee arthroplasty between the leading continents.

Background: Scientific progress in the field of knee and hip arthroplasty has enabled the preservation of mobility and quality of life in the case of patients with many primary degenerative and (post-) traumatic joint diseases. This comparative study aims to investigate differences in scientific performance between the leading continents in the field of hip and knee arthroplasty. Methods: Using specific search terms all studies published by the scientific leading continents Europe, North America, Asia and Oceania listed in the Web of Science databases were included. All identified publications were analysed and comparative conclusions were drawn regarding the qualitative and quantitative scientific merit of each continent. Results: Europe, followed by North America, Asia, and Oceania, had the highest overall number of publications in the field of arthroplasty. Since 2000, there has been a strong increase in knee arthroplasty publication rate, particular pronounced in Asia. Studies performed and published in North America and those on knee arthroplasty received the highest number of fundings. Publications regarding hip arthroplasty achieved the highest average citation rate. In contradistinction to the others, in North America most funding was provided by private agencies. Conclusion: Although Europe showed the highest total number of publications, authors and institutions, arthroplasty research from North America received greater scientific attention and financial support. Measured by citations, publications on hip arthroplasty attained higher scientific interest and studies on knee arthroplasty received higher economic affection.

Network-Based In Silico Analysis of New Combinations of Modern Drug Targets with Methotrexate for Response-Based Treatment of Rheumatoid Arthritis.

BACKGROUND: Methotrexate (MTX), sulfonamides, hydroxychloroquine, and leflunomide have consistently resulted in remission with relatively mild to moderate adverse effects in patients with rheumatoid arthritis (RA). Modern medications outperform traditional treatments in that they target the pathological processes that underlie the development of RA. METHODS: Following PRISMA guidelines, the authors accomplished a systematic review of the clinical efficacy of RA drugs, including the biologics such as Tumor Necrosis Factor-alpha inhibitors (TNF-α i) like Etanercept, Infliximab, Golimumab, and Adalimumab, kinase inhibitors (JAK inhibitors including Baricitinib and Tofacitanib), SyK inhibitors like Fos-tamatinib, MAPK inhibitors such as Talmapimod, T-cell inhibitors (Abatacept), IL6 blockers (Tocilizumab), and B cells depleters (Rituximab). These drugs have been found to increase remission rates when combined with MTX. A bioinformatics-based network was designed applying STRING-MODEL and the DrugBank database for the aforementioned drugs and MTX and, finally, employed for this systematic review. RESULTS: Current research demonstrates that non-TNF-α inhibitor biologicals are particularly helpful in treating patients who did not respond well to conventional medications and TNF-α inhibitors. Despite being effective, these innovative drugs have a higher chance of producing hazardous side effects. The in silico investigations suggested an uncovered molecular interaction in combining MTX with other biological drugs. The STRING-MODEL showed that DHFR, TYMS, and ATIC, as the receptors of MTX, interact with each other but are not connected to the major interacted receptors. CONCLUSIONS: New game-changing drugs including Mavrilimumab, Iguratimod, Upadacitinib, Fenebrutinib, and nanoparticles may be crucial in controlling symptoms in poorly managed RA patients. Emerging therapeutic targets like Toll-like 4 receptors, NLRP3 inflammasome complexes, and mesenchymal stem cells can further transform RA therapy.

Size and Morphology of the Anterior and Posterior Cruciate Ligaments at Different Pediatric Age Intervals: An MRI Analysis.

Background: The incidence of anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) tears in children and adolescents has increased over the past decade, with increasing numbers of ACL and PCL reconstructions in this patient population. Purpose: To evaluate the size and morphology of both the ACL and the PCL by magnetic resonance imaging (MRI) in different pediatric age groups. Study Design: Cross-sectional study; Level of evidence, 3. Methods: MRI examinations of 127 knees (67 female, 60 male; aged 0-18 years) were analyzed retrospectively. The cohort was split into 6 age subgroups, 1 subgroup for every 3 years (minimum 8 patients per subgroup). The following parameters were measured by 2 independent raters at 2 different time points: ACL length, anteroposterior and mediolateral ACL width, sagittal and coronal ACL inclination, inclination of the intercondylar notch, bicondylar width, notch width, coronal ACL and PCL width, PCL length, and sagittal width of the lateral femoral condyle. The following indices, areas, and volumes were calculated: sagittal width of the lateral femoral condyle/PCL length, ACL area and volume, notch width index, ACL width/notch width, PCL width/notch width, ACL width/bicondylar width, and PCL width/bicondylar width. A correlation analysis was performed for patient age, height, weight, and body mass index (BMI). Results: ACL length was between 18 and 37 mm, and ACL width was between 4 and 6 mm. PCL length ranged between 27 and 43 mm, while PCL width was between 7 and 9 mm. Growth of the cruciate ligaments was the most pronounced between the ages of 4 and 12 years. Correlations with size and weight were strong, while BMI correlated slightly with the measurements. Measurements in female patients were slightly larger than in their male counterparts between the ages of 0 and 6 years, while male patients tended to have larger values starting from ages 7 to 9 years. These values were significantly larger in male patients from the ages of 16 to 18 years (P < .05). Conclusion: This study provides normative data on the morphology of pediatric anatomic features in the knee as a basis for age-appropriate and individualized surgical care of ACL and PCL injuries in children and adolescents.

Two-Year Results of Injectable Matrix-Associated Autologous Chondrocyte Transplantation in the Hip Joint: Significant Improvement in Clinical and Radiological Assessment.

PURPOSE: Articular cartilage defects are a prevalent consequence of femoroacetabular impingement (FAI) in young active patients. In accordance with current guidelines, large chondral lesions of the hip joint over 2 cm2 are recommended to be treated with matrix-associated, autologous chondrocyte transplantation (MACT); however, the conditions in the hip joint are challenging for membrane-based MACT options. Injectable MACT products can solve this problem. The purpose of the trial was to assess clinical and radiological outcomes 24 months after injectable MACT of focal chondral lesions caused by FAI. METHODS: We present data of 21 patients with focal cartilage defects of the hip [3.0 ± 1.4 cm2 (mean ± SD)], ICRS Grade III and IV caused by CAM-type impingement, who underwent arthroscopic MACT (NOVOCART® Inject) and FAI correction. The outcome was evaluated with the patient-reported outcome instruments iHOT33 and EQ-5D-5L (index value and VAS), whilst graft morphology was assessed based on the MOCART score over a follow-up period of 24 months. RESULTS: The iHOT33 score increased significantly from 52.9 ± 21.1 (mean ± SD) preoperatively to 85.8 ± 14.8 (mean ± SD; p < 0.0001) 24 months postoperatively. The EQ-5D-5L index value (p = 0.0004) and EQ-5D VAS (p = 0.0006) showed a statistically significant improvement as well. MRI evaluation after 24 months showed successful integration of the implant in all patients with a complete defect filling in 11 of 14 patients. CONCLUSIONS: Injectable MACT for the treatment of full-thickness chondral lesions of the hip joint due to FAI in combination with FAI correction improved symptoms, function, and quality of life in the treated cohort. Alongside the treatment of the underlying pathology by the FAI correction, the developed cartilage defect can be successfully repaired by MACT, which is of considerable clinical relevance.

Accuracy of Personalized Computed Tomographic 3D Templating for Acetabular Cup Placement in Revision Arthroplasty.

Background: Revision hip arthroplasty presents a surgical challenge, necessitating meticulous preoperative planning to avert complications like periprosthetic fractures and aseptic loosening. Historically, assessment of the accuracy of three-dimensional (3D) versus two-dimensional (2D) templating has focused exclusively on primary hip arthroplasty. Materials and Methods: In this retrospective study, we examined the accuracy of 3D templating for acetabular revision cups in 30 patients who underwent revision hip arthroplasty. Utilizing computed tomography scans of the patients' pelvis and 3D templates of the implants (Aesculap Plasmafit, B. Braun; Aesculap Plasmafit Revision, B. Braun; Avantage Acetabular System, Zimmerbiomet, EcoFit 2M, Implantcast; Tritanium Revision, Stryker), we performed 3D templating and positioned the acetabular cup implants accordingly. To evaluate accuracy, we compared the planned sizes of the acetabular cups in 2D and 3D with the sizes implanted during surgery. Results: An analysis was performed to examine potential influences on templating accuracy, specifically considering factors such as gender and body mass index (BMI). Significant statistical differences (p < 0.001) in the accuracy of size prediction were observed between 3D and 2D templating. Personalized 3D templating exhibited an accuracy rate of 66.7% for the correct prediction of the size of the acetabular cup, while 2D templating achieved an exact size prediction in only 26.7% of cases. There were no statistically significant differences between the 2D and 3D templating methods regarding gender or BMI. Conclusion: This study demonstrates that 3D templating improves the accuracy of predicting acetabular cup sizes in revision arthroplasty when compared to 2D templating. However, it should be noted that the predicted implant size generated through 3D templating tended to overestimate the implanted implant size by an average of 1.3 sizes.

Indications and possible limitations using medio-plantar plate systems in tarsometatarsal 1 fusions - A cadaveric study.

BACKGROUND: The tarsometatarsal 1 arthrodesis is an adequate treatment for moderate to severe hallux valgus deformity and instability of the first ray. Plantar plating arthrodesis has been shown to provide better mechanical stability and fewer postoperative complications than screw fixation or medial plating. The medio-plantar plate is a new plate design for Lapidus arthrodesis. It could combine the biomechanical advantages of the plantar plate and the anatomical overview of a medial plate. However, the implanted material can cause irritation of the tibialis anterior, which in some cases may require removal of the material. The purpose of this study was to examine the possibility of tendon irritation following medio-plantar first tarsometatarsal joint arthrodesis using cadaveric specimens. METHODS: The study involved the simulated surgical procedure of medio-plantar plate arthrodesis on 30 lower extremities. After the plates were fixed, a thorough examination of the feet was conducted to assess any tendon irritation and to determine a recommendation for placement of the medio-plantar plate based on the Olewnik classification. RESULTS: Irritation of the tibialis anterior tendon components with the medio-plantar plate depends mainly on the anatomic norm variant, classified according to Olewnik et al. A medio-plantar plate is particularly recommended in TA tendon Olewnik type 3 and type 5. The positioning of a medio-plantar plate in Olewnik type 1 and type 2 tendons depends on the anatomic fit of the medio-plantar plate and the bony configuration of the TMT 1 joint. A large portion of the TA tendon must be detached, so a different plate design may be preferred in these patients. CONCLUSIONS: TMT 1 arthrodesis with medio-plantar plating of the first tarsometatarsal joint should be performed considering the anatomic TA tendon variations. LEVEL OF EVIDENCE: Level V, Expert Opinion includes Case Reports and Technique Tips.

[Digital tools in musculoskeletal rehabilitation]. / Digitale Hilfsmittel in der muskuloskelettalen Rehabilitation.

The demographic transition in combination with the increasing demands of society and a growing shortage of skilled workers are leading to a shortage of care in musculoskeletal rehabilitation, especially in times of the pandemic. Digital interventions represent an opportunity to reintegrate patients with musculoskeletal dysfunctions into everyday life. The changes to the legal basis enable physicians and therapists to support the rehabilitation of their patients with reimbursable apps and digital applications and to permanently integrate learned skills into their daily lives. Telerehabilitation technologies, apps, telerobotics and mixed reality offer the opportunity to complement and optimize existing care structures and to redesign specialized therapeutic home visits with modern technology in a new and contemporary way.

[New perspectives in orthopedics : Developments through neurotechnology and metaverse]. / Neue Perspektiven in der Orthopädie : Entwicklungen durch Neurotechnologie und Metaversum.

The combination of neurotechnology and metaverse holds high potentials for orthopedics, as it offers a broad spectrum of possibilities to overcome the limits of traditional medical care. The vision of a medical metaverse providing the infrastructure as a link for innovative technologies opens up new opportunities for therapy, medical collaborations and practical, personalized training for aspiring physicians. However, risks and challenges, such as security and privacy, health-related issues, acceptance by patients and doctors, as well as technical hurdles and access to the technologies, remain. Hence, future research and development is paramount. Nonetheless, due to technological progress, the exploration of new research areas, and the improved availability of the technologies paired with cost reduction, the prospects for neurotechnology and metaverse in orthopedics are promising.

Endoscopically Assisted Percutaneous Harvesting of the Flexor Hallucis Tendon in Zone 2: An Anatomical Study.

BACKGROUND: Flexor hallucis longus (FHL) transfer is a well-established method for treating chronic Achilles tendon ruptures and tendinopathy. Harvesting of the FHL tendon in zone 2 results in greater length but is also associated with an increased risk of injury to the medial plantar nerve and requires an additional plantar incision. Because of the anatomic proximity of the FHL tendon to the tibial neurovascular bundle in zone 2, the purpose of this study was to investigate the risk of vascular or nerve injury with arthroscopic assisted percutaneous tenotomy in zone 2 of the FHL tendon. METHODS: Endoscopically assisted percutaneous FHL transfer was performed on 10 right lower extremities from 10 cadaveric human specimens. The FHL tendon lengths and the relationship between FHL tendon and the tibial neurovascular bundle at zone 2 was analyzed. RESULTS: We observed a complete transection of the medial plantar nerve in 1 case (10%). The mean length of the FHL tendon was 54.7 ± 9.5 mm and the mean distance from the distal stump of the FHL tendon to local neurovascular structures was 1.3 ± 0.7 mm. CONCLUSION: There is a risk of neurovascular injury after endoscopic FHL tenotomy in zone 2. The tenotomy site is within 2 mm of the local neurovascular structures in the majority of cases. The additional length gained from this technique is unlikely to be required for the majority of FHL tendon transfer procedures. If additional length is needed, we would recommend the use of intraoperative ultrasonography or a mini-open approach to minimize injury risk. LEVEL OF EVIDENCE: Level V, expert opinion.

Subgroup analysis of scientific performance in the field of arthroplasty.

Introduction: Arthroplasty is the final treatment option for maintaining mobility and quality of life in many primary degenerative and (post-) traumatic joint diseases. Identification of research output and potential deficits for specific subspecialties may be an important measure to achieve long-term improvement of patient care in this field. Methods: Using specific search terms and Boolean operators, all studies published since 1945 to the subgroups of arthroplasty listed in the Web of Science Core Collection were included. All identified publications were analysed according to bibliometric standards, and comparative conclusions were drawn regarding the scientific merit of each subgroup. Results: Most publications investigated the subgroups of septic surgery and materials followed by approach, navigation, aseptic loosening, robotic and enhanced recovery after surgery (ERAS). In the last 5 years, research in the fields of robotic and ERAS achieved the highest relative increase in publications In contrast, research on aseptic loosening has continued to lose interest over the last 5 years. Publications on robotics and materials received the most funding on average while those on aseptic loosening received the least. Most publications originated from USA, Germany, and England, except for research on ERAS in which Denmark stood out. Relatively, publications on aseptic loosening received the most citations, whereas the absolute scientific interest was highest for the topic infection. Discussion: In this bibliometric subgroup analysis, the primary scientific outputs focused on septic complications and materials research in the field of arthroplasty. With decreasing publication output and the least financial support, intensification of research on aseptic loosening is urgently recommended.

Development of Open Backend Structures for Health Care Professionals to Improve Participation in App Developments: Pilot Usability Study of a Medical App.

BACKGROUND: Efficient digitization in medicine still is in its infancy but undeniably has great potential for current and future challenges in health care. Thus far, the rollout of medical apps has not resulted in widespread use of smartphones in the German health care sector-the reasons for this have not been clarified so far. Nevertheless, the lack of user involvement in the development process and content creation might contribute to low acceptance of these products. OBJECTIVE: This study aims to outline an approach to involve medical expertise without any coding knowledge for developing medical app content and functions. METHODS: An end user-operable backend was built. Its usability was evaluated using a usability evaluation test protocol. The results of the usability tests were evaluated by the app development team, and the usability test was repeated for optimizing backend usability. In total, 40 criteria to measure the ease of app usage were defined a priori. The usability test comprised 20 tasks that had to be fulfilled. Usability tasks were analyzed for completion, dropout, and test duration. Due to the COVID-19 pandemic, digital videoconferencing platforms (Zoom and QuickTime Player) were used to complete usability questionnaires. Finally, several backend-based apps for several specialties (infectiology, plastic and reconstructive surgery, and orthopedics) were developed by health care professionals as prototypes. RESULTS: Initial usability testing was conducted with 5 participants (4 men and 1 woman; mean age 39.2, SD 5.97 years). All of them could complete the assigned backend tasks with only a few workflow interruptions and some minor errors. After usability optimization, the workflow completion time decreased from 5.03 minutes to 3.50 minutes, indicating a time saving. The basic backend structure was clear to all test users and the handling was intuitive to learn. Some minor errors in the backend occurred during the test rounds. The apps developed using the aforementioned approach are in clinical use as a proof of concept. CONCLUSIONS: Backends offering operability for medical professionals might have great potential for app development in the mobile health sector. Sophisticated and time-saving usability are pivotal for the acceptance of medical software, as illustrated by the backend-based apps presented herein, which are in clinical use as a proof of concept. Basic interventions are essential and sufficient for adequate usability optimization. Practicable, well-structured software usability evaluation is possible based on the usability evaluation test protocol.

Optimal drilling at femoral head-neck junction for treatment of the femoral head necrosis: Experimental and numerical evaluation.

BACKGROUND: Advanced core decompression (ACD) is a relative new technique for treatment of early stages of avascular femoral head necrosis. Although it is a promising treatment option, there is a need to modify this technique for achieving higher hip survival rates. An idea was to combine this technique with the lightbulb procedure in order to get a complete removal of the necrosis. This study aimed at evaluating the fracture risk of the femora treated by the combined Lightbulb-ACD technique as the basis for clinical application. METHODS: Subject-specific models were generated from CT scan data of five intact femora. Several treated models were then created from each intact bone and simulated during normal walking activity. Biomechanical testing was additionally performed on 12 pairs of cadaver femora to confirm the simulation results. FINDINGS: The finite element results revealed that the risk factor of the treated models with a 8 mm-drill increased, but was not significantly greater than that of their corresponding intact models. However, for the femur treated with a 10 mm-drill, the risk factor increased significantly. Fracture always initiated on the femoral neck, i.e. it was either subcapital or transcervical fracture. Our biomechanical testing results correlated well with the simulation data which confirmed the usefulness and effectiveness of the bone models. INTERPRETATION: The combined Lightbulb-ACD technique using a 10 mm drill increased the fracture risk of femur postoperatively. A drill of up to 8 mm at the anterior head-neck junction did not however lead to the weakening of the femur so that full load bearing may be possible.

Comparison of the Accuracy of 2D and 3D Templating for Revision Total Hip Replacement.

INTRODUCTION: Revision hip arthroplasty is a challenging surgical procedure, especially in cases of advanced acetabular bone loss. Accurate preoperative planning can prevent complications such as periprosthetic fractures or aseptic loosening. To date, the accuracy of three-dimensional (3D) versus two-dimensional (2D) templating has been evaluated only in primary hip and knee arthroplasty. METHODS: We retrospectively investigated the accuracy of 3D personalized planning of reinforcement cages (Burch Schneider) in 27 patients who underwent revision hip arthroplasty. Personalized 3D modeling and positioning of the reinforcement cages were performed using computed tomography (CT) of the pelvis of each patient and 3D templates of the implant. To evaluate accuracy, the sizes of the reinforcement cages planned in 2D and 3D were compared with the sizes of the finally implanted cages. Factors that may potentially influence planning accuracy such as gender and body mass index (BMI) were analyzed. RESULTS: There was a significant difference (p = 0.003) in the accuracy of correct size prediction between personalized 3D templating and 2D templating. Personalized 3D templating predicted the exact size of the reinforcement cage in 96.3% of the patients, while the exact size was predicted in only 55.6% by 2D templating. Regarding gender and BMI, no statistically significant differences in planning accuracy either for 2D or 3D templating were observed. CONCLUSION: Personalized 3D planning of revision hip arthroplasty using Burch Schneider reinforcement cages leads to greater accuracy in the prediction of the required size of implants than conventional 2D templating.

Proposal of a New Rating Concept for Digital Health Applications in Orthopedics and Traumatology.

BACKGROUND: Health-related mobile applications (apps) are rapidly increasing in number. There is an urgent need for assessment tools and algorithms that allow the usability and content criteria of these applications to be objectively assessed. The aim of this work was to establish and validate a concept for orthopedic societies to rate health apps to set a quality standard for their safe use. METHODS: An objective rating concept was created, consisting of nine quality criteria. A self-declaration sheet for app manufacturers was designed. Manufacturers completed the self-declaration, and the app was examined by independent internal reviewers. The pilot validation and analysis were performed on two independent health applications. An algorithm for orthopedic societies was created based on the experiences in this study flow. RESULTS: "Sprunggelenks-App" was approved by the reviewers with 45 (98%) fulfilled criteria and one (2%) unfulfilled criterion. "Therapie-App" was approved, with 28 (61%) met criteria, 6 (13%) unfulfilled criteria and 12 (26%) criteria that could not be assessed. The self-declaration completed by the app manufacturer is recommended, followed by a legal and technical rating performed by an external institution. When rated positive, the societies' internal review using independent raters can be performed. In case of a positive rating, a visual certification can be granted to the manufacturer for a certain time frame. CONCLUSION: An objective rating algorithm is proposed for the assessment of digital health applications. This can help societies to improve the quality assessment, quality assurance and patient safety of those apps. The proposed concept must be further validated for inter-rater consistency and reliability.