Paterson S I, Amin A K, Hall A C
Centre for Integrative Physiology, School of Biomedical Sciences, University of Edinburgh, Edinburgh, UK.
Department of Trauma and Orthopaedic Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK.
Osteoarthritis Cartilage. 2015 Feb;23(2):257-65. doi: 10.1016/j.joca.2014.10.004. Epub 2014 Oct 30.
Exposure of articular cartilage to static air results in changes to the extracellular matrix (ECM) and stimulates chondrocyte death, which may cause joint degeneration. However during open orthopaedic surgery, cartilage is often exposed to laminar airflow, which may exacerbate these damaging effects. We compared drying in static and moving air in terms of cartilage appearance, hydration and chondrocyte viability, and tested the ability of saline-saturated gauze to limit the detrimental effects of air exposure.
Articular cartilage from bovine metatarsophalangeal joints (N = 50) and human femoral heads (N = 6) was exposed for 90 min to (1) static air (2) airflow (up to 0.34 m/s), or (3) airflow (0.18 m/s), covered with gauze. Following air exposure, cartilage was also rehydrated (0.9% saline; 120 min) to determine the reversibility of drying effects. The influence of airflow was assessed by studying macroscopic appearance, and quantifying superficial zone (SZ) chondrocyte viability and cartilage hydration.
Airflow caused advanced changes to cartilage appearance, accelerated chondrocyte death, and increased dehydration compared to static air. These effects were prevented if cartilage was covered by saline-saturated gauze. Cartilage rehydration reversed macroscopic changes associated with drying but the chondrocyte death was not altered. Chondrocytes at the cut edge of cartilage were more sensitive to drying compared to cells distant from the edge.
Airflow significantly increased articular cartilage dehydration and chondrocyte death compared to static air. As laminar airflow is routinely utilised in operating theatres, it is essential that articular cartilage is kept wet via irrigation or by covering with saline-saturated gauze to prevent chondrocyte death.
将关节软骨暴露于静态空气中会导致细胞外基质（ECM）发生变化，并刺激软骨细胞死亡，这可能会导致关节退变。然而，在骨科开放手术中，软骨常常暴露于层流空气中，这可能会加剧这些破坏作用。我们比较了静态空气和流动空气中软骨的外观、水合作用及软骨细胞活力，并测试了饱和盐水纱布限制空气暴露有害影响的能力。
将来自牛跖趾关节（N = 50）和人类股骨头（N = 6）的关节软骨暴露于（1）静态空气、（2）气流（最高0.34 m/s）或（3）气流（0.18 m/s）中90分钟，其中（3）覆盖有纱布。空气暴露后，软骨也进行再水化（0.9%盐水；120分钟）以确定干燥效果的可逆性。通过研究宏观外观、量化表层区（SZ）软骨细胞活力和软骨水合作用来评估气流的影响。
与静态空气相比，气流导致软骨外观出现更严重的变化，加速软骨细胞死亡，并增加脱水。如果软骨用饱和盐水纱布覆盖，这些影响可得到预防。软骨再水化逆转了与干燥相关的宏观变化，但软骨细胞死亡情况未改变。与远离边缘的细胞相比，软骨切缘处的软骨细胞对干燥更敏感。
与静态空气相比，气流显著增加了关节软骨脱水和软骨细胞死亡。由于手术室常规使用层流空气，因此必须通过冲洗或用饱和盐水纱布覆盖来保持关节软骨湿润，以防止软骨细胞死亡。
