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Purpose: The aim of the present study was to compare 45° and 60° of sagittal femoral tunnel angles in terms of anterior tibial translation (ATT), valgus angle and graft in situ force following anterior cruciate ligament reconstruction (ACLR). Methods: Ten porcine knees were subjected to the following loading conditions: (1) 89 N anterior tibial load at 35° (full extension), 60° and 90° of knee flexion and (2) 5 N m valgus tibial moment at 35° and 45° of knee flexion. ATT and graft in situ force of the intact anterior cruciate ligament (ACL) and ACLR were collected using a robotic universal force/moment sensor (UFS) testing system for (1) ACL intact, (2) ACL‐deficient (ACLD) and (3) two different ACLR using different sagittal femoral tunnel angles (coronal 45°/sagittal 45° and coronal 45°/sagittal 60°). Results: During the anterior tibial load, the femoral tunnel angle of ACLR knees at coronal 45°/sagittal 45° and 60° had significantly higher ATT than that of the ACL‐intact knees at 60° of knee flexion (p < 0.05). The femoral tunnel angle of ACLR knees at coronal 45°/sagittal 60° had significantly lower graft in situ force than that of the ACL‐intact knees at 60° and 90° of knee flexion (p < 0.05). During the valgus tibial moment, the femoral tunnel angle of ACLR knees at coronal 45°/sagittal 45° and 60° had significantly lower graft in situ force than that of the ACL‐intact knees at all knee flexions (p < 0.05). Conclusions: The femoral tunnel angle of ACLR knees at coronal 45°/sagittal 45° provided similar ATT, valgus angle and graft in situ force to that of ACLR knees at coronal 45°/sagittal 60°. Therefore, both femoral tunnel angles could be used in ACLR, as the sagittal femoral tunnel angle does not appear to be relevant in post‐operative knee stability. Level of Evidence: Not applicable. [ABSTRACT FROM AUTHOR]

This document discusses the importance of developing engineering technologies to prevent musculoskeletal injuries and improve treatment and rehabilitation strategies. It highlights recent advancements in implant design, surgical techniques, rehabilitation protocols, and injury prevention technologies. The document also introduces a special issue of Bioengineering dedicated to advanced engineering technologies in orthopedic research, featuring eight papers on topics such as posture control in the elderly, artificial intelligence preoperative planning, shape memory implants for osteoporotic fractures, in vitro joint testing systems, pedicle screw performance, knee arthroplasty designs, gait analysis for fracture healing, and shoulder arthrometry. The papers aim to improve the prevention of injuries, enhance implant compatibility, optimize post-operative function, and provide innovative diagnostic and therapeutic technologies for musculoskeletal diseases. [Extracted from the article]

Soft actuators that mimic the softness and deformability of living organisms have great potential for use in various fields. For most soft actuators, achieving both reprogrammable shape and high work capacity is crucial but challenging. These properties are mutually exclusive for liquid crystal elastomers (LCEs), an important type of soft actuators. Herein, a room‐temperature shape‐programmable LCE capable of high‐energy actuation is developed. Our approach utilizes hydrogen bonds to stabilize the aligned liquid crystal phases. The slow recovery of H‐bonds at room temperature provides a specific processing window, during which the sample shape can be programmed after the thermal treatment. The temperature‐dependent rearrangement of hydrogen bonds allows for fabrication of actuators with customized shapes in a facile do‐it‐yourself manner. Additionally, the integration of strong covalent cross‐links is vital for holding structural integrity. The combination of non‐covalent and covalent cross‐linking significantly improves the mechanical properties, enabling the actuators to perform reversible actuation with a work capacity (440 kJ m−3) higher than that of traditional LCEs (<100 kJ m−3). This study provides a turnkey strategy to address the conflict between shape reprogrammability and work capacity, advancing the development of soft actuators. [ABSTRACT FROM AUTHOR]