Advancements in tissue engineering are crucial for successfully healing tendon-bone connections, especially in situations like anterior cruciate ligament (ACL) restoration. This study presents a new and innovative three-dimensional scaffold, reinforced with nanofibers, that is specifically intended for acellular tendon complexes. The scaffold consists of a distinct layered arrangement comprising an acellular tendon core, a middle layer of polyurethane/type I collagen (PU/Col I) yarn, and an outside layer of poly (L-lactic acid)/bioactive glass (PLLA/BG) nanofiber membrane. Every layer is designed to fulfill specific yet harmonious purposes. The acellular tendon core is a solid structural base and a favorable environment for tendon cell functions, resulting in considerable tensile strength. The central PU/Col I yarn layer is vital in promoting the tendinogenic differentiation of stem cells derived from tendons and increasing the expression of critical tendinogenic factors. The external PLLA/BG nanofiber membrane fosters the process of bone marrow mesenchymal stem cells differentiating into bone cells and enhances the expression of markers associated with bone formation. Our scaffold's biocompatibility and multi-functional design were confirmed through extensive in vivo evaluations, such as histological staining and biomechanical analyses. These assessments combined showed notable enhancements in ACL repair and healing. This study emphasizes the promise of multi-layered nanofiber scaffolds in orthopedic tissue engineering and also introduces new possibilities for the creation of improved materials for regenerating the tendon-bone interface.

Objective: Patients who undergo a biplanar ascending medial open‐wedge high tibial osteotomy with an excessive correction angle might experience patella infera and even knee pain after surgery. The purpose of this study was to identify the cut‐off points for the degree of knee varus correction of open‐wedge high tibial osteotomy, which is related to the symptomatic patellar position change.Methods: This retrospective study included 124 patients (mean age 61.69 ± 6.28 years; 78 women, 46 men) with varying degrees of varus knee osteoarthritis. All patients had undergone standard biplanar medial open‐wedge high tibial osteotomy. They were divided into nine groups according to the change in hip–knee–ankle angle. Plain radiographs and three‐dimensional CT images were obtained preoperatively and 18 months postoperatively. Patellar height was assessed using the Caton–Deschamps index, the Insall–Salvati index, and the Blackburne–Peel index. The patellofemoral index and patellar tilt were used to evaluate the degree of horizontal displacement of the patella. The varus correction, medial–proximal tibial angles, joint line convergence angles, and hip–knee–ankle angles were also measured. The subjective score was evaluated using the Western Ontario and McMaster Universities osteoarthritis index (WOMAC).Results: There were significant changes in patella indexes in each group after surgery, among which there was no significant difference in patellar height changes for Groups A to F (p > 0.05), which were significantly lower than those in Group G, H, and I (p < 0.001). The patellar tilt and patellofemoral index also followed the same trend. The improvement in WOMAC scores for Groups G, H, and I was also significantly less for Groups A to F (p < 0.001).Conclusion: The patellar height, patellar tilt, and patellofemoral index all changed significantly in parallel with increasing degrees of osteotomy correction. The cut‐off points for correction angle are 12.5° to 13.4°. When the correction angle is larger than this range, the patellar position can be significantly affected. Postoperative patellofemoral joint pain may be related to the changes in patella position.

Background: Although bone marrow stimulation (BMS) is believed to promote rotator cuff healing, there is no comparison of clinical outcomes and structural integrity between different BMS techniques in patients undergoing arthroscopic rotator cuff repair (ARCR). Purpose/Hypothesis: The purpose of this study was to compare the clinical outcomes and structural integrity between BMS inside the rotator cuff footprint area (“greenhouse” technique) and BMS outside the rotator cuff footprint area (“crimson duvet” technique). It was hypothesized that the new “greenhouse” technique would provide better clinical outcomes and structural integrity at short-term follow-up. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: This study included 60 patients who underwent ARCR using the “greenhouse” technique or “crimson duvet” technique (n = 30 per group). Functional outcomes at 24 months postoperatively were assessed including the ASES (American Shoulder and Elbow Surgeons) score, CMS (Constant-Murley score), UCLA (University of California, Los Angeles) score, SST (Simple Shoulder Test), VAS (visual analog scale) for pain, and range of motion consisting of forward elevation, external rotation, and internal rotation. The minimal clinically important difference, patient acceptable symptom state, substantial clinical benefit, and maximum outcome improvement were also compared between the 2 groups. Structural integrity was evaluated by magnetic resonance imaging at 2 years postoperatively and compared between the 2 groups. Results: All functional outcomes improved significantly compared with preoperatively in both groups at the last follow-up (all P < .001). However, there were no significant differences between the 2 groups postoperatively. Overall, 52 patients (86.7%) achieved the minimal clinically important difference, 44 patients (73.3%) achieved the patient acceptable symptom state, 45 patients (75.0%) achieved the substantial clinical benefit, and 31 patients (51.7%) achieved the maximum outcome improvement, without significant differences between the 2 groups. The retear rate after ARCR in the “greenhouse” group was 6.7% and 10.0% in the “crimson duvet” group, which was not significantly different. Conclusion: In ARCR, both the “greenhouse” and “crimson duvet” techniques exhibited significant functional improvement in patients with rotator cuff tears. The new “greenhouse” technique provided comparable clinical outcomes and structural integrity compared with the traditional “crimson duvet” technique at short-term follow-up. Registration: NCT04686968 (ClinicalTrials.gov)