Functional outcomes, such as joint flexion and gait, are important indicators of efficacy in musculoskeletal research. Current technologies that objectively assess these parameters, including visual tracking systems and force plates, are challenging to deploy in long-term translational and clinical studies. To that end, we developed a wearable device that measures both physical activity and joint flexion using a single integrated sensor and magnet system, and hypothesized that it could evaluate post-operative functional recovery in an unsupervised setting. To demonstrate the feasibility of measuring joint flexion, we first compared knee motion from the wearable device to that acquired from a motion capture system to confirm that knee flexion measurements during normal human gait, predicted via changes in magnetic field strength, closely correlated with data acquired by motion capture. Using this system, we then monitored a porcine cohort after bilateral stifle arthrotomy to investigate longitudinal changes in physical activity and joint flexion. We found that unsupervised activity declined immediately after surgery, with a return to pre-operative activity occurring over a period of 2 weeks. By providing objective, individualized data on locomotion and joint function, this magnet-based system will facilitate the in vivo assessment of novel therapeutics in translational orthopaedic research.

中文翻译：

---

一个基于磁铁的可穿戴系统，用于评估人类和大型动物的活动和关节屈伸。

功能结果，例如关节屈伸和步态，是肌肉骨骼研究功效的重要指标。客观地评估这些参数的当前技术，包括视觉跟踪系统和测力板，对于在长期的翻译和临床研究中进行部署提出了挑战。为此，我们开发了一种可穿戴设备，该设备使用单个集成的传感器和磁体系统来测量身体活动和关节弯曲，并假设它可以在无人监督的情况下评估术后功能恢复情况。为了证明测量关节屈曲的可行性，我们首先将可穿戴设备的膝盖运动与从运动捕捉系统获得的膝盖运动进行了比较，以确认通过磁场强度变化预测的正常人步态中的膝盖屈曲测量结果，与运动捕捉所获取的数据紧密相关。然后，使用该系统，我们在双侧膝关节置换手术后监测了一个猪群，以研究体力活动和关节屈曲的纵向变化。我们发现，无监督活动在手术后立即下降，并在2周内恢复到术前活动。通过提供有关运动和关节功能的客观，个性化数据，该基于磁体的系统将有助于平移整形外科研究中新型疗法的体内评估。在2周内恢复了术前活动。通过提供有关运动和关节功能的客观，个性化数据，该基于磁体的系统将有助于平移整形外科研究中新型疗法的体内评估。在2周内恢复了术前活动。通过提供有关运动和关节功能的客观，个性化数据，该基于磁体的系统将有助于平移整形外科研究中新型疗法的体内评估。