Snijders Thom E, Willemsen Koen, van Gaalen Steven M, Castelein Rene M, Weinans Harrie, de Gast Arthur
1 Clinical Orthopedic Research Centre - mN, Zeist, Utrecht, The Netherlands.
2 Department of Orthopaedics, University Medical Centre Utrecht, Utrecht, The Netherlands.
Hip Int. 2019 Jan;29(1):41-50. doi: 10.1177/1120700018759306. Epub 2018 May 17.
: Dislocation is 1 of the main reasons for revision of total hip arthroplasty but dislocation rates have not changed in the past decades, compromising patients' well-being. Acetabular cup orientation plays a key role in implant stability and has been widely studied. This article investigates whether there is a consensus on optimal cup orientation, which is necessary when using a navigation system.
: A systematic search of the literature in the PubMed, Embase and Cochrane databases was performed (March 2017) to identify articles that investigated the direct relationship between cup orientation and dislocation, including a thorough evaluation of postoperative cup orientation assessment methods.
: 28 relevant articles evaluating a direct relation between dislocation and cup orientation could not come to a consensus. The key reason is a lack of uniformity in the assessment of cup orientation. Cup orientation is assessed with different imaging modalities, different methodologies, different definitions for inclination and anteversion, several reference planes and distinct patient positions.
: All available studies lack uniformity in cup orientation assessment; therefore it is impossible to reach consensus on optimal cup orientation. Using navigation systems for placement of the cup is inevitably flawed when using different definitions in the preoperative planning, peroperative placement and postoperative evaluation. Further methodological development is required to assess cup orientation. Consequently, the postoperative assessment should be uniform, thus differentiating between anterior and posterior dislocation, use the same definitions for inclination and anteversion with the same reference plane and with the patient in the same position.
脱位是全髋关节置换翻修的主要原因之一，但在过去几十年中脱位率并未改变，这对患者的健康造成了损害。髋臼杯的方向在植入物稳定性中起着关键作用，并且已经得到了广泛研究。本文探讨在使用导航系统时，对于最佳杯方向是否存在共识，这是必要的。
于2017年3月在PubMed、Embase和Cochrane数据库中对文献进行系统检索，以识别研究杯方向与脱位之间直接关系的文章，包括对术后杯方向评估方法的全面评估。
28篇评估脱位与杯方向之间直接关系的相关文章未能达成共识。关键原因是杯方向评估缺乏一致性。杯方向通过不同的成像方式、不同的方法、对倾斜和前倾角的不同定义、多个参考平面以及不同的患者体位进行评估。
所有现有研究在杯方向评估方面缺乏一致性；因此，不可能就最佳杯方向达成共识。在术前规划、术中放置和术后评估中使用不同定义时，使用导航系统放置杯不可避免地存在缺陷。需要进一步的方法学发展来评估杯方向。因此，术后评估应该统一，从而区分前脱位和后脱位，对倾斜和前倾角使用相同的定义，采用相同的参考平面且患者处于相同体位。
