Davda K, Lali F V, Sampson B, Skinner J A, Hart A J
Imperial College, Charing Cross Campus, Fulham Palace Road, London W6 8RF, UK.
J Bone Joint Surg Br. 2011 Jun;93(6):738-45. doi: 10.1302/0301-620X.93B6.25804.
We retrospectively analysed concentrations of chromium and cobalt ions in samples of synovial fluid and whole blood taken from a group of 92 patients with failed current-generation metal-on-metal hip replacements. We applied acid oxidative digestion to our trace metal analysis protocol, which found significantly higher levels of metal ion concentrations in blood and synovial fluid than a non-digestive method. Patients were subcategorised by mode of failure as either 'unexplained pain' or 'defined causes'. Using this classification, chromium and cobalt ion levels were present over a wider range in synovial fluid and not as strongly correlated with blood ion levels as previously reported. There was no significant difference between metal ion concentrations and manufacturer of the implant, nor femoral head size below or above 50 mm. There was a moderately positive correlation between metal ion levels and acetabular component inclination angle as measured on three-dimensional CT imaging. Our results suggest that acid digestion of samples of synovial fluid samples is necessary to determine metal ion concentrations accurately so that meaningful comparisons can be made between studies.
我们回顾性分析了从一组92例当代金属对金属髋关节置换失败患者采集的滑液和全血样本中的铬和钴离子浓度。我们在痕量金属分析方案中采用了酸氧化消解，结果发现与非消解方法相比，血液和滑液中的金属离子浓度显著更高。患者按失败模式分为“不明原因疼痛”或“明确病因”两类。采用这种分类方法，滑液中铬和钴离子水平的分布范围更广，且与血离子水平的相关性不如先前报道的那么强。金属离子浓度与植入物制造商之间没有显著差异，股骨头尺寸在50毫米以下或以上也无显著差异。在三维CT成像上测量的金属离子水平与髋臼组件倾斜角度之间存在中度正相关。我们的结果表明，对滑液样本进行酸消解对于准确测定金属离子浓度是必要的，以便在研究之间进行有意义的比较。
