The Avon Orthopaedic Centre, Southmead Hospital, Bristol, UK.
Acta Orthop. 2013 Oct;84(5):448-52. doi: 10.3109/17453674.2013.845812. Epub 2013 Oct 1.
Previously, we have documented surface temperatures recorded by thermography great enough to cause osteonecrosis of the femoral head during hip resurfacing. We now performed an in vitro investigation with 3 questions: (1) whether water irrigation reduced bone surface temperature, (2) whether external bone temperatures were similar to core temperatures, and (3) whether blunting of the reamer affected temperature generation.
Using an ox-bone model, 57 femoral heads were peripherally reamed. The surface temperatures of bone were measured using a thermal camera and internal bone temperatures were measured using 2 theromocouples. We measured the effects of cooling with water at room temperature and with ice-cooled water. Progressive blunting of reamers was assessed over the 57 experiments.
Mean and maximum temperatures generated during peripheral reaming were greater when no irrigation was used. Ice-cold saline protected femoral heads from thermal damage. External bone temperatures were much greater than internal temperatures, which were not sufficiently elevated to cause osteonecrosis regardless of lavage. Blunting of the reamer was not found to have a statistically significant effect in this study.
Cooling with ice-cooled water is recommended. Internal bone temperatures are not elevated despite the high surface temperatures reached during femoral head resurfacing.
此前，我们记录了髋关节表面置换术中热成像仪记录到的足以导致股骨头坏死的表面温度。现在我们进行了一项体外研究，提出了 3 个问题：（1）水冲洗是否降低了骨表面温度；（2）外部骨温度是否与核心温度相似；（3）扩孔器的钝化是否影响温度产生。
使用牛骨模型，对 57 个股骨头进行外周扩孔。使用热像仪测量骨表面温度，使用 2 个热电偶测量内部骨温度。我们测量了室温下用水和冰水冷却的效果。在 57 次实验中评估了扩孔器逐渐钝化的效果。
在不冲洗的情况下，外周扩孔过程中产生的平均温度和最高温度更高。冰冷的生理盐水保护股骨头免受热损伤。外部骨温度远高于内部温度，无论冲洗与否，内部温度都不会升高到导致骨坏死的程度。在这项研究中，未发现扩孔器的钝化有统计学意义的影响。
建议使用冰水冷却。尽管在股骨头表面置换术中达到了很高的表面温度，但内部骨温度并没有升高。
