Laaksonen Inari, Lorimer Michelle, Gromov Kirill, Rolfson Ola, Mäkelä Keijo T, Graves Stephen E, Malchau Henrik, Mohaddes Maziar
Harris Orthopaedic Laboratory, Massachusetts General Hospital, Boston, MA, USA.
Harvard Medical School, Boston, MA, USA.
Clin Orthop Relat Res. 2017 Dec;475(12):3015-3022. doi: 10.1007/s11999-017-5417-3. Epub 2017 Jun 23.
Earlier results with porous tantalum acetabular cups in revision THA generally have been favorable. Recently there has been some evidence presented that porous tantalum cups might decrease the risk of rerevision in the setting of revision hip surgery performed owing to prosthetic joint infection (PJI). As the data supporting this assertion come from a study with a limited study population, examining this issue with a large registry approach may be enlightening.
QUESTIONS/PURPOSES: By combining results from two large, national registries, we asked: (1) Do porous tantalum cups show improved survival after revision THA compared with other cementless designs? (2) Does the use of porous tantalum cups influence survivorship when rerevision for PJI is the endpoint?
A total of 2442 first-time THA revisions with porous tantalum cups and 4401 first-time revisions with other uncemented cups were included in this collaborative study between the Australian and Swedish national joint registries. The mean age of the patients was 69 years (range, 19-97 years), 3754 (55%) of the patients were women, and the mean followup for the porous tantalum and uncemented control groups were 3.0 years (SD, ± 2.1 years) and 3.4 years (SD, ± 2.3 years), respectively. Concomitant stem revision was more common in the porous tantalum group (43% versus 36%). The use of porous tantalum augments also was analyzed as a proxy for more complex acetabular reconstructions. In an attempt to further reduce selection bias, we performed subgroup analysis for primary operations attributable to osteoarthritis and first revision attributable to aseptic loosening.
Kaplan-Meier survivorship with rerevisison for any reason up to 7 years was comparable between the porous tantalum cup group and the uncemented cup control group (86% [95% CI, 85%-89%] and 87% [95% CI, 85%-89%], respectively; p = 0.85) and the overall survivorship up to 7 years with a second revision for PJI as the endpoint (97% [95% CI, 95%-98%] and 97% [95% CI, 96%-98%], respectively; p = 0.64). Excluding procedures where augments had been used or studying primary osteoarthritis and first revision owing to aseptic loosening subgroups did not change this result.
Implant survival for a porous tantalum cup in first-time THA revision was similar to the survival of the uncemented cup control group. With the numbers available, no benefit in survival with rerevision for infection as the endpoint could be ascribed to the porous tantalum cup group, as has been suggested by earlier work. Further studies with acetabular bone deficiency data, greater insight into host comorbidity factors, and a longer followup are needed to corroborate or refute these results.
Level III, therapeutic study.
在翻修全髋关节置换术中，多孔钽髋臼杯早期的应用结果总体良好。最近有证据表明，在因假体周围感染（PJI）而行的翻修髋关节手术中，多孔钽杯可能会降低再次翻修的风险。由于支持这一论断的数据来自一项研究人群有限的研究，采用大型登记研究方法来研究这个问题可能会有所启发。
问题/目的：通过合并两个大型国家登记研究的结果，我们提出以下问题：（1）与其他非骨水泥设计相比，多孔钽杯在翻修全髋关节置换术后的生存率是否有所提高？（2）以因PJI再次翻修为终点时，多孔钽杯的使用是否会影响生存率？
澳大利亚和瑞典国家关节登记研究的这项合作研究纳入了2442例首次使用多孔钽杯的全髋关节置换翻修术和4401例首次使用其他非骨水泥杯的翻修术。患者的平均年龄为69岁（范围19 - 97岁），3754例（55%）患者为女性，多孔钽杯组和非骨水泥对照组的平均随访时间分别为3.0年（标准差±2.1年）和3.4年（标准差±2.3年）。多孔钽杯组同时进行股骨柄翻修更为常见（43%对36%）。多孔钽增强物的使用也作为更复杂髋臼重建的替代指标进行了分析。为了进一步减少选择偏倚，我们对因骨关节炎导致的初次手术和因无菌性松动导致的首次翻修进行了亚组分析。
多孔钽杯组和非骨水泥杯对照组在7年内因任何原因再次翻修的Kaplan - Meier生存率相当（分别为86% [95%可信区间，85% - 89%]和87% [95%可信区间，85% - 89%]；p = 0.85），以因PJI进行二次翻修为终点时，7年内的总体生存率也相当（分别为97% [95%可信区间，95% - 98%]和97% [95%可信区间，96% - 98%]；p = 0.64）。排除使用增强物的手术或研究因无菌性松动亚组的原发性骨关节炎和首次翻修情况，结果未改变。
首次全髋关节置换翻修术中多孔钽杯的植入生存率与非骨水泥杯对照组相似。就现有数据而言，如早期研究所暗示的，以感染再次翻修为终点时，多孔钽杯组在生存率方面并无优势。需要进一步研究髋臼骨缺损数据、更深入了解宿主合并症因素以及更长时间的随访来证实或反驳这些结果。
III级，治疗性研究。
