Arthroscopic Autologous Iliac Crest Grafting with an Adjustable Loop Suspensory Device Yields Favorable Outcomes for Anterior Shoulder Instability with Glenoid Defects.

PURPOSE: This study aims to evaluate the clinical and radiological outcomes of the arthroscopic autologous iliac crest grafting (AICG) procedure with an adjustable-loop suspensory fixation device in the treatment of anterior shoulder instability (ASI) with glenoid bone defects. METHODS: A retrospective review was conducted on the patients who underwent arthroscopic AICG with an adjustable-loop suspensory fixation device from January 2017 to December 2020. Patients with traumatic ASI, significant glenoid bone defects, and a minimum follow-up of 24 months were included. Patient-reported outcomes (PROs), including the Oxford Shoulder Instability Score (OSIS), the Rowe score, the Walch-Duplay score, the Constant score, and the Visual Analogue Score (VAS), were compared preoperatively and postoperatively. Radiological assessments using computed tomography (CT) were performed before and after the procedure. Additional data on active range of motion, recurrence events, and complications were recorded. RESULTS: A total of 42 patients were included in the study, with a mean follow-up time of 35.2 months ranging from 25.1 to 55.9 months. Mean preoperative OSIS, Rowe score, Walch-Duplay score, and Constant score significantly improved from 24.4±7.2, 25.0±9.0, 25.2±9.8, 87.5±7.1 to 42.4±4.9, 92.4±8.1, 87.9±8.3, 93.6±4.5 at the last follow-up, respectively. All patients exceeded the minimal clinically important difference (MCID) for OSIS, Rowe, and Walch-Duplay scores. The graft union rate was 100%, and the glenoid area increased significantly from 82.5% preoperatively to 100.1% at the final follow-up. No patient experienced a recurrence of instability. Two recorded complications included one case of dysesthesia around the donor site and one case of postoperative shoulder stiffness. CONCLUSIONS: The outcomes of the arthroscopic AICG procedure, which utilizes an adjustable-loop suspensory fixation device, demonstrated stable bone graft fixation, high rates of graft integration, favorable clinical results, and a low incidence of complications. Moreover, the remodeling of the graft during the follow-up period significantly restored the width and concavity of the inferior glenoid, contributing to the overall recovery. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Circadian Rhythm-Regulated ADSC-Derived sEVs and a Triphasic Microneedle Delivery System to Enhance Tendon-to-Bone Healing.

Modulating the inflammatory microenvironment to reconstruct the fibrocartilaginous layer while promoting tendon repair is crucial for enhancing tendon-to-bone healing in rotator cuff repair (RCR), a persistent challenge in orthopedics. Small extracellular vesicles (sEVs) hold significant potential to modulate inflammation, yet the efficient production of highly bioactive sEVs remains a substantial barrier to their clinical application. Moreover, achieving minimally invasive local delivery of sEVs to the tendon-to-bone interface presents significant technical difficulties. Herein, the circadian rhythm of adipose-derived stem cells is modulated to increase the yield and enhance the inflammatory regulatory capacity of sEVs. Circadian rhythm-regulated sEVs (CR-sEVs) enhance the cyclic adenosine monophosphate signaling pathway in macrophage (Mφ) via platelet factor 4 delivery, thereby inhibiting Mφ M1 polarization. Subsequently, a triphasic microneedle (MN) scaffold with a tip, stem, and base is designed for the local delivery of CR-sEVs (CR-sEVs/MN) at the tendon-to-bone junction, incorporating tendon-derived decellularized extracellular matrix in the base to facilitate tendon repair. CR-sEVs/MN mitigates inflammation, promotes fibrocartilage regeneration, and enhances tendon healing, thereby improving biomechanical strength and shoulder joint function in a rat RCR model. Combining CR-sEVs with this triphasic microneedle delivery system presents a promising strategy for enhancing tendon-to-bone healing in clinical settings.

Photocontrolled Reversible Solid-Fluid Transitions of Azopolymer Nanocomposites for Intelligent Nanomaterials.

Intelligent polymer nanocomposites are multicomponent and multifunctional materials that show immense potential across diverse applications. However, to exhibit intelligent traits such as adaptability, reconfigurability and dynamic properties, these materials often require a solvent or heating environment to facilitate the mobility of polymer chains and nanoparticles, rendering their applications in everyday settings impractical. Here intelligent azopolymer nanocomposites that function effectively in a solvent-free, room-temperature environment based on photocontrolled reversible solid-fluid transitions via switching flow temperatures (Tfs) are shown. A range of nanocomposites is synthesized through the grafting of Au nanoparticles, Au nanorods, quantum dots, or superparamagnetic nanoparticles with photoresponsive azopolymers. Leveraging the reversible cis-trans photoisomerization of azo groups, the azopolymer nanocomposites transition between solid (Tf above room temperature) and fluid (Tf below room temperature) states. Such photocontrolled reversible solid-fluid transitions empower the rewriting of nanopatterns, correction of nanoscale defects, reconfiguration of complex multiscale structures, and design of intelligent optical devices. These findings highlight Tf-switchable polymer nanocomposites as promising candidates for the development of intelligent nanomaterials operative in solvent-free, room-temperature conditions.

Is playing ma-jong, chess and cards associated with a lower incidence of shoulder pain in Chinese elderly adults? The cross-sectional and longitudinal evidence from CHARLS.

BACKGROUND: The association between playing Ma-jong, chess and cards (PMCC) and shoulder pain among elderly adults in China remains unclear. The present study aimed to examine the association based on a nationally representative large-scale survey. METHODS: The study used two waves of data from China Health and Retirement Longitudinal Study (CHARLS) in 2015 and 2018. All subjects met the inclusion criteria were classified based on the results of the CHARLS wave questionnaire. Logistic regression models were conducted to analyze the cross-sectional and longitudinal association between PMCC and shoulder pain. Odds ratios (OR) were reported to indicate the strength of the association. RESULTS: In total, 8125 participants aged over 60 years (48.3 % male; mean age 67.9 ± 6.4 years) were enrolled in a cross-sectional association study in 2015, and further 6861 elderly adults were followed up in 2018. The overall prevalence of shoulder pain in the cross-sectional population was 15.6 %. In the non-PMCC and PMCC groups, the incidence of shoulder pain was 16.6 % and 10.7 %, respectively (P < 0.001). In the fully adjusted model, the results showed a significant association between PMCC and shoulder pain (OR: 0.798, 95 % CI: 0.662-0.963, P = 0.018). In the longitudinal analysis from 2015 to 2018, the incidence of new-occurrence shoulder pain in non-PMCC and PMCC groups was 22.1 %, and 18.5 %, respectively (P = 0.004). In the fully adjusted model, compared with the non-PMCC group, the risk of the occurrence of shoulder pain for individuals with PMCC was lower (OR: 0.832, 95 % CI: 0.709-0.975, P = 0.023). CONCLUSIONS: PMCC is associated with lower incidence of shoulder pain, which provides evidence for PMCC as a potential protective factor in the occurrence of shoulder pain.

Adipose-derived stem cell-based optimization strategies for musculoskeletal regeneration: recent advances and perspectives.

Musculoskeletal disorders are the leading causes of physical disabilities worldwide. The poor self-repair capacity of musculoskeletal tissues and the absence of effective therapies have driven the development of novel bioengineering-based therapeutic approaches. Adipose-derived stem cell (ADSC)-based therapies are being explored as new regenerative strategies for the repair and regeneration of bone, cartilage, and tendon owing to the accessibility, multipotency, and active paracrine activity of ADSCs. In this review, recent advances in ADSCs and their optimization strategies, including ADSC-derived exosomes (ADSC-Exos), biomaterials, and genetic modifications, are summarized. Furthermore, the preclinical and clinical applications of ADSCs and ADSC-Exos, either alone or in combination with growth factors or biomaterials or in genetically modified forms, for bone, cartilage, and tendon regeneration are reviewed. ADSC-based optimization strategies hold promise for the management of multiple types of musculoskeletal injuries. The timely summary and highlights provided here could offer guidance for further investigations to accelerate the development and clinical application of ADSC-based therapies in musculoskeletal regeneration.

Shape-Morphing Liquid-Crystal polymers.

Liquid-crystal polymers are a type of representative material combining the order-disorder transition of liquid crystals and the superior properties of polymers. The phase transition from the liquid-crystal phase to the isotropic state of mesogens causes large, controllable, and reversible deformation of polymers; thus, liquid-crystal polymers have emerged as one of the most valuable candidates for shape-morphing materials. Therefore, this review will focus on the recent development of shape-morphing liquid-crystal polymers, including the modes of energy conversions, material design strategies and further applications. In the main, novel material design methods and a wide range of application of shape-morphing liquid-crystal polymers are discussed.

Decreased numbers and sex-based differences of circulating regulatory T cells in patients with seropositive undifferentiated arthritis.

AIMS: CD4+ T cells play crucial roles as both mediators and regulators of the pathogenesis of rheumatoid arthritis (RA). However, the characteristics of CD4+ T cell subpopulations in the earliest stage of RA development remain unclear. Hence, we determined the proportions and absolute counts of circulating CD4+ T cell subsets in patients with seropositive undifferentiated arthritis (SUA), the early and preclinical stage of RA. METHODS: Peripheral blood samples and clinical information were collected from 177 patients with SUA, 104 patients with RA, and 120 healthy controls. All patients were newly diagnosed and untreated. Proportions and absolute counts of CD4+ T cell subpopulations were determined by flow cytometric analysis. RESULTS: In patients with SUA, percentages and absolute counts of circulating regulatory T (Treg) cells were decreased significantly and Th17/Treg cell ratios were abnormally increased, whereas Th17 cell numbers were similar to those in healthy controls. In addition, sex-based differences in circulating Treg cells were observed, with female SUA patients having lower proportions and absolute counts of Treg cells than those in males. Moreover, female patients with SUA had higher erythrocyte sedimentation rates and 28-joint Disease Activity Scores than those in males. CONCLUSION: Immune tolerance deficiency resulting from an abnormal reduction in circulating Treg cells might be the most crucial immunological event in the earliest stage of RA. The sex-specific disparity in Treg cells should also be considered for immunoregulatory and preventive strategies targeting early RA.