The detrimental effects of hyperlipidemia on the healing of rotator cuff tears are well documented. The proposed underlying mechanisms for these effects include alterations in the extracellular matrix, inflammation, and oxidative stress, which hamper the reparative processes in the affected tendon tissues. Recent therapeutic strategies target these pathways, reflecting a growing body of research dedicated to mitigating these effects and promoting healing. This literature review aims to provide a comprehensive understanding of the pathophysiology underlying rotator cuff tears, examine the interplay between hyperlipidemia and rotator cuff tear healing, synthesize current knowledge on contributing biological mechanisms, and outline potential therapeutic interventions to optimize clinical management and treatment outcomes for patients.

Background: Proximal humerus nails, frequently used for managing proximal humerus fractures, significantly enhance rotational stability and reinforce fractured fragments. Few research exists regarding the optimal number and positioning of distal screws.This study aimed to assess the stability of diverse screw configurations and scrutinize screw distribution and bone stress via finite element analysis. Methods: The humerus intramedullary nail (Humerus Interlocking Nail System; TDM) underwent assessment using finite element analysis applied to a humerus model. Three groups were established based on varying distal screw numbers and locations: all 3 distal locking holes were used in group 1; 2 screws (dynamic hole and proximal static hole) in group 2, and 2 screws (dynamic hole and distal static hole) in group 3. Finite element analysis computed stress distribution within the implant and bone for each group.A 1-mm fracture gap was simulated at the surgical neck, and stress distributions were analyzed in both normal and osteoporotic bone models. Results: Using two screws did not compromise rotational stability. Stress distribution analysis revealed stability across all groups without reaching failure strength. Group 3 exhibited a minor rise in component 11 (direct stress [force per unit area] acting on the positive and negative 1 faces in the 1-axis. direction) and component 22 (direct stress [force per unit area] acting on the positive and negative 2 faces in the 2-axis direction) stress, remaining below failure strength thresholds. Group 1 exhibited the lowest von Mises stress in the nail and screws, while groups 2 and 3 did not reach failure strength levels. Findings remained consistent in the osteoporotic model. Conclusions All 3 groups demonstrated rotational stability concerning stress distribution, indicating that using 2 screws for distal fixation does not adversely affect stability. This suggests the potential for saving surgical time and reducing radiation exposure without compromising stability.

Background: Not reducing the posterior malleolar fragment could have an impact on the alignment and stability of syndesmosis since the posterior inferior tibiofibular ligament (PITFL) originates at the posterior malleolar fragment. Given that these alignment and stability changes may contribute to discomfort and pain, further research may be required. We think that our new classification method will be able to help improve understanding of treatment methods for posterior malleolar fractures. Methods: We retrospectively analyzed 206 patients who underwent surgeries for ankle fractures in our orthopedic clinic between April 2014 and December 2022 and were verified to have posterior malleolar fractures in plain radiography, computed tomography (CT), and magnetic resonance imaging (MRI). We performed a probing test to determine whether syndesmosis was stable. Results: We were able to classify the 206 cases into the following 5 types: type 1 (31 cases, 15.0%), extraincisural fragment with an intact fibular notch; type 2 (98 cases, 47.5%), posterolateral fragment extending into the fibular notch; type 3 (37 cases, 17.9%), posteromedial 2-part fragment involving the medial malleolus; type 4 (19 cases, 9.2%), large posterolateral triangular fragment;and type 5 (21 cases, 10.1%), shell-like PITFL avulsion (< 2 mm) in a CT axial view or PITFL periosteal sleeve avulsion (PITPSA) in arthroscopic or MRI findings. Conclusions This new system that adds the PITPSA type for the classification of posterior malleolar fractures may be a useful approach to managing these injuries and may aid in treatment decision-making. It could be important to consider ligament surgery when treating PITPSA.

Background: This study aimed to compare the effectiveness and complications between classic palmaris longus tendon landmark-based corticosteroid injection (CI) and transverse carpal ligament (TCL)-penetrating CI for carpal tunnel syndrome (CTS). Methods: We performed a landmark-based CI on one hand and a TCL-penetrating CI on the other side after randomization in 30 consecutive patients with bilateral CTS. The pain visual analog scale (VAS) and the Boston Carpal Tunnel Questionnaire (BCTQ) were assessed at baseline, 4 weeks, and 3 and 6 months after injection. Skin hypopigmentation of the injection site was evaluated using the modified Vancouver scar scale (mVSS). Pain during needle insertion was evaluated using a VAS for each hand. Results: The mean patient age was 56 ± 11 years (range, 32–77 years), and 27 patients (90.0%) were women. The pain VAS, BCTQ scores, and the incidence of skin hypopigmentation were not significantly different between the 2 groups after injection, but the mean mVSS scores were significantly higher in the landmark-based CI group at all time points. The pain VAS score during needle insertion was significantly higher in the TCL-penetrating CI group. Conclusions When comparing the pain VAS and BCTQ scores, the difference between the 2 groups was not statistically significant. TCL-penetrating CI causes considerable pain during needle insertion but causes less severe skin hypopigmentation than landmark-based CI in CTS treatment.

Background: This study aimed to report the short- and midterm outcomes of arthroscopic rotator cuff repair (ARCR) and reverse shoulder arthroplasty (RSA) in weight-bearing shoulders. Methods: This retrospective multicenter study included 19 cases of ARCR and 10 cases of RSA performed in weight-bearing shoulders from 2009 to 2021. In the ARCR group, postoperative 6-month magnetic resonance imaging confirmed the tendon integrity. In the RSA group, scapular notching, acromial fracture, and implant failure were assessed using plain radiographs, and complications were recorded. In both groups, preoperative and postoperative range of motion and functional scores were documented, along with subjective satisfaction and arm use for weight-bearing on the shoulders. For patients followed up for > 5 years, a midterm analysis was performed. Results: The ARCR group included 8 men and 11 women (average age, 58.8 ± 8.0 years). Initially, Patte types 1, 2, and 3 were noted in 9, 8, and 2 patients, respectively, and 4 patients exhibited full-thickness subscapularis tears. Four patients showed supraspinatus retear, and 2 patients showed subscapularis retear. Retear of any rotator cuff was observed in 5 patients (26.3%). Twelve patients were followed up for > 5 years; 11 (91.7%) used their operated arm for weight-bearing and 9 (75.0%) were satisfied. The RSA group included 5 men and 5 women (average age, 74.3 ± 7.9 years). Procedures included RSAs for cuff tear arthropathy (n = 6), osteoarthritis (n = 3), and fracture nonunion (n = 1). No cases of dislocation, prosthesis loosening, or disassociation were observed throughout the follow-up. However, 1 patient required implant removal due to infection, and 4 patients showed stage 1 scapular notching. Five patients were followed up for > 5 years, all of whom expressed satisfaction and used their operated arms for weight-bearing, despite mean forward flexion (107.5° ± 12.6°) and American Shoulder and Elbow Surgeons score (61.5 ± 5.3) being less than reported patient acceptable symptomatic state (110° and 76, respectively). Conclusions Both ARCR and RSA showed promising outcomes in terms of weight-bearing on the operated arm and subjective satisfaction at short- and midterm follow-up. Therefore, neither of these surgeries should be considered contraindicated for patients with weight-bearing shoulder conditions.

Background: To identify the optimal surgical technique for single-level anterior cervical discectomy and fusion (ACDF), this study compared surgical outcomes and incidence of adjacent segment degeneration (ASD) in patients undergoing single-level ACDF using cage alone single-level fusion and plate fixation techniques. Methods: This single-center retrospective study (2003–2018) included patients who underwent single-level ACDF with either plate fixation (PLATE) or cage (CAGE) alone. The radiologic and clinical outcomes between the 2 surgical groups were compared over a 4-year follow-up period. Outcomes of interest included parameters related to range of motion, sagittal alignment, as well as fusion, subsidence, and ASD rates. Clinical outcomes were evaluated using the Neck Disability Index (NDI) and visual analog scale (VAS) for pain. Dysphagia and hoarseness rates were estimated based on medical records. Results: Forty-seven patients were included (n=17 in CAGE group). In the CAGE group, 94.1% of the patients had Bridwell grade 1 or 2, compared to 83.3% in the PLATE group (p = 0.396). Subsidence occurred in 12.5% and 3.6% of the CAGE and PLATE cases, respectively (p = 0.543). Segmental kyphosis progressed in the CAGE group compared to the PLATE group at 12, 24, and 48 months (p < 0.001). Radiographic ASD was observed in 41.2% and 30.0% of patients in the CAGE and PLATE groups, respectively, with a higher incidence in the upper segments for both groups. Preoperative NDI scores were similar between the groups; however, postoperatively, the CAGE group had significantly lower NDI scores (3.50 ± 2.74 vs. 8.00 ± 5.81) at 4 years (p = 0.020). Neck pain VAS scores also showed significant improvement in the CAGE group (2.33 ± 2.94) compared with that in the PLATE group (3.07 ± 2.31) at 4 years (p = 0.045). Both groups showed comparable arm pain VAS scores at 2 and 4 years postoperatively. Postoperative dysphagia occurred in 1 patient in the PLATE group, resolving almost completely by 1 year. Conclusions Single-level ACDF using a cage alone technique demonstrated favorable radiologic and clinical outcomes overall compared to plate-augmented ACDF. However, plate augmentation is recommended for patients with severe cervical kyphosis or those at high risk of subsidence.

Background: Several studies have investigated the morphological risk factors contributing to posterior cruciate ligament (PCL) injury. However, no study has focused on the injury patterns of intrasubstance tears or tibial avulsion fractures in relation to morphologies and regional bone quality. This study aimed to investigate the impact of the knee morphology and regional bone quality of the proximal tibia on the PCL injury pattern. Methods: This retrospective study compared the radiological features of 76 patients with PCL injuries (PI group) and 76 matched patients with normal PCL (control group). The PI group was divided into 2 subgroups: PCL avulsion fracture (PAF subgroup; n = 43) and PCL intrasubstance tear (PIT subgroup; n = 33). Measurements included the coronal notch width index, coronal tibial slope, medial and lateral posterior tibial slopes, and medial tibial depth. Three Hounsfield unit average measurements were taken from the proximal tibia around the PCL insertion site to create a summative measure of overall bone quality. Results: The medial tibial depth and coronal notch width index were significantly lower in the PI group than those in the control group (medial tibial depth: 2.04 ± 0.77 vs. 3.02 ± 1.04, p = 0.017; coronal notch width index: 0.21 ± 0.03 vs. 0.24 ± 0.03, p = 0.041). In the subgroup analysis, medial tibial depth and Hounsfield unit were significantly lower in the PAF subgroup than in the PIT subgroup (medial tibial depth: 1.74 ± 0.66 vs. 2.43 ± 0.77, p = 0.008, Hounsfield unit: 89.48 ± 31.73 vs. 120.15 ± 29.24, p = 0.004). Binary logistic regression analysis showed that medial tibial depth (odds ratio [OR], 0.161; p < 0.001) and Hounsfield unit (OR, 0.950;p < 0.001) were independent risk factors for PCL tibial avulsion fractures. Conclusions Lower notch width index and medial tibial depth are associated with PCL injuries. Shallower medial tibial depth and lower Hounsfield unit measurements around the PCL insertion site were associated with an increased incidence of PCL avulsion fractures. These findings may assist clinicians in identifying patients at risk of distinct PCL injury patterns.

Background: The removal of a well-fixed acetabular cup is a challenging, labor-intensive, and time-consuming step during revision hip arthroplasty. Although the advent of the manual osteotome, Explant, has simplified the procedure, it is still a stressful process as it dissipates the surgeon’s strength and time and risks an iatrogenic pelvic fracture. Recently, EZX, a powered tool for extraction of well-fixed acetabular cups with semicircular blade was invented. This study aimed to compare Explant and EZX in an experimental condition for their efficacy and safety. Methods: Cementless acetabular cups were press-fitted to 20 hemipelvic polyurethane models using foam adhesives. Ten cups were removed with each tool for comparison of the elapsed time, loads on the entire hemipelvis, periacetabular strain and temperature, volume of periacetabular bone removed, and diameter of the remaining acetabular rim. Strains and loads were quantitatively assessed using strain gauges and load cells for precise and reliable measurements. Results: The mean duration required to remove a well-fixed cup with EZX was 38.5 seconds (range, 25–55), whereas that with Explant was 543.7 seconds (range, 214–1,051) (p < 0.001). The load on the entire hemipelvis with EZX (mean, 9.1 kgf; range, 6.4–11.3) was 33% lower than that with Explant (mean, 13.6 kgf; range, 9.2–17.1) (p < 0.001). The periacetabular peak strains at the 3 positions with EZX were significantly lower than those with Explant (p < 0.001). The temperature during the removal did not differ significantly between the 2 tools. Although the mean volume of bone loss with Explant was 2.4 mL more than that with EZX (p < 0.001), the mean diameters of the remaining acetabular rim were not significantly different, measuring 54.1 mm with both tools. Conclusions The present experiment revealed that a well-fixed cup could be removed using a powered tool with less strength and time and less load on the entire pelvis. Although the powered tool removed a larger volume of bone, the diameters of the remaining acetabular rims were equivalent. This tool may help surgeons remove well-fixed cups in a short time and reduce the deforming load on the bone around the cup without increasing the size of the subsequent reconstruction cup.

Background: and Purpose: Plasma biomarkers, including phosphorylated tau (ptau217), glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL), are promising tools for detecting Alzheimer’s disease (AD) pathology. However, cross-laboratory reproducibility remains a challenge, even when using identical analytical platforms such as single-molecule array (Simoa). This study aimed to compare plasma biomarker measurements (ptau217, GFAP, and NfL) between 2 laboratories, the University of Gothenburg (UGOT) and DNAlink, and evaluate their associations with amyloid positron emission tomography (PET) imaging. Methods: Plasma biomarkers were measured using Simoa platforms at both laboratories:the UGOT and DNAlink Incorporation. Diagnostic performance for predicting amyloid PET positivity, cross-laboratory agreement, and the impact of normalization techniques were assessed. Bland-Altman plots and correlation analyses were employed to evaluate agreement and variability. Results: Plasma ptau217 concentrations exhibited strong correlations with amyloid PET global centiloid values, with comparable diagnostic performance between laboratories (area under the curve=0.94 for UGOT and 0.95 for DNAlink). Cross-laboratory agreement for ptau217 was excellent (r=0.96), improving further after natural log transformation. GFAP and NfL also demonstrated moderate to strong correlations (r=0.86 for GFAP and r=0.99 for NfL), with normalization reducing variability. Conclusions Plasma biomarker measurements were consistent across laboratories using identical Simoa platforms, with strong diagnostic performance and improved agreement after normalization. These findings support the scalability of plasma biomarkers for multicenter studies and underscore their potential for standardized applications in AD research and clinical practice.

Background: and Purpose: This clinical practice guideline provides evidence-based recommendations for treatment of dementia, focusing on cholinesterase inhibitors and N-methyl-D-aspartate (NMDA) receptor antagonists for Alzheimer’s disease (AD) and other types of dementia. Methods: Using the Population, Intervention, Comparison, Outcomes (PICO) framework, we developed key clinical questions and conducted systematic literature reviews. A multidisciplinary panel of experts, organized by the Korean Dementia Association, evaluated randomized controlled trials and observational studies. Recommendations were graded for evidence quality and strength using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Results: Three main recommendations are presented: (1) For AD, cholinesterase inhibitors (donepezil, rivastigmine, galantamine) are strongly recommended for improving cognition and daily function based on moderate evidence; (2) Cholinesterase inhibitors are conditionally recommended for vascular dementia and Parkinson’s disease dementia, with a strong recommendation for Lewy body dementia; (3) For moderate to severe AD, NMDA receptor antagonist (memantine) is strongly recommended, demonstrating significant cognitive and functional improvements. Both drug classes showed favorable safety profiles with manageable side effects. Conclusions This guideline offers standardized, evidence-based pharmacologic recommendations for dementia management, with specific guidance on cholinesterase inhibitors and NMDA receptor antagonists. It aims to support clinical decision-making and improve patient outcomes in dementia care. Further updates will address emerging treatments, including amyloid-targeting therapies, to reflect advances in dementia management.