Liu Ping, Wang Guoqiang, Zhou Bing, Kang Yijun
Department of Spine Surgery, The Second Xiangya Hospital, Central South University, Changsha City, China.
J Orthop Surg Res. 2025 Apr 29;20(1):432. doi: 10.1186/s13018-025-05692-5.
The incidence of abnormal metal ion levels following spinal surgery has been inconsistent across various studies. Metal implants, commonly used in spinal surgeries, can release ions that may accumulate in the bloodstream, leading to potential adverse health effects. Therefore, a comprehensive meta-analysis is necessary to assess the levels of metal ions in patients after spinal surgery.
We performed a systematic review and meta-analysis to evaluate metal ion levels after spinal surgery. A thorough search was conducted across four databases (PubMed, Embase, Web of Science, and Cochrane Library) up to September 2024. Studies were included if they measured serum or whole blood levels of metals such as chromium, cobalt, titanium, nickel, aluminum, or other relevant ions in patients post-spinal surgery. Data were extracted and analyzed using random-effects models to account for variability between studies. Funnel plots and Egger's test were used to assess publication bias, and I statistics were employed to measure heterogeneity. Sensitivity analyses of the included studies were conducted to ensure the robustness of the findings. The Newcastle-Ottawa Scale (NOS) was used for quality assessment, evaluating factors such as study selection, comparability, and outcome measurement.
A total of thirty-one studies, comprising data from over 1,404 patients, met the inclusion criteria. Postoperative levels of chromium, titanium, cobalt, aluminum, and nickel were significantly elevated compared to preoperative levels. The pooled standardized mean difference (SMD) for chromium was 2.50 (95% CI 1.74-3.26), for titanium was 2.05 (95% CI 1.41-2.70), for cobalt was 2.28 (95% CI 1.24-3.32), for aluminum was 0.75 (95% CI 0.24-1.27), and for nickel was 1.41 (95% CI 0.03-2.79). Subgroup analyses revealed variations based on the type of surgery, with higher SMDs observed in degenerative spinal conditions compared to scoliosis and spinal deformity-related surgeries for most metals. Significant heterogeneity was observed among studies (I > 70%), but no evidence of publication bias was detected. Sensitivity analyses confirmed the stability of the results.
This meta-analysis confirms a significant postoperative increase in metal ion levels, particularly for chromium, titanium, cobalt, aluminum, and nickel, in patients following spinal surgery. These elevated metal ion levels raise concerns about potential long-term health risks, underscoring the importance of postoperative monitoring. Given the high heterogeneity among studies, more robust and standardized research is needed to establish clear clinical thresholds for safe metal ion levels and to assess the long-term implications of these findings. Regular monitoring of metal ion concentrations in patients with spinal implants may be crucial for early detection and prevention of metal-related complications.
脊柱手术后金属离子水平异常的发生率在各项研究中并不一致。脊柱手术中常用的金属植入物会释放离子，这些离子可能在血液中蓄积，从而对健康产生潜在的不良影响。因此，有必要进行一项全面的荟萃分析来评估脊柱手术后患者体内的金属离子水平。
我们进行了一项系统评价和荟萃分析，以评估脊柱手术后的金属离子水平。截至2024年9月，我们在四个数据库（PubMed、Embase、Web of Science和Cochrane图书馆）中进行了全面检索。纳入的研究需测量脊柱手术后患者血清或全血中的金属（如铬、钴、钛、镍、铝）或其他相关离子的水平。使用随机效应模型提取和分析数据，以考虑研究之间的差异。采用漏斗图和Egger检验评估发表偏倚，并使用I统计量测量异质性。对纳入的研究进行敏感性分析，以确保研究结果的稳健性。采用纽卡斯尔-渥太华量表（NOS）进行质量评估，评估研究选择、可比性和结果测量等因素。
共有31项研究符合纳入标准，涉及1404多名患者的数据。与术前水平相比，术后铬、钛、钴、铝和镍的水平显著升高。铬的合并标准化平均差（SMD）为2.50（95%CI 1.74-3.26），钛为2.05（95%CI 1.41-2.70），钴为2.28（95%CI 1.24-3.32），铝为0.75（95%CI 0.24-1.27），镍为1.41（95%CI 0.03-2.79）。亚组分析显示，根据手术类型存在差异，与脊柱侧弯和脊柱畸形相关手术相比，大多数金属在退行性脊柱疾病中的SMD更高。研究之间观察到显著的异质性（I>70%），但未检测到发表偏倚的证据。敏感性分析证实了结果的稳定性。
这项荟萃分析证实，脊柱手术后患者体内金属离子水平术后显著升高，尤其是铬、钛、钴、铝和镍。这些升高的金属离子水平引发了对潜在长期健康风险的担忧，凸显了术后监测的重要性。鉴于研究之间的高度异质性，需要更稳健和标准化的研究来确定安全金属离子水平的明确临床阈值，并评估这些发现的长期影响。定期监测脊柱植入物患者的金属离子浓度对于早期发现和预防金属相关并发症可能至关重要。
