Reducing variation in hip replacement outcomes: understanding psoas tendon impingement

全髋关节置换术（THR）是一种成功的手术，但需要翻修的器械数量持续增加。高达40%的患者报告手术后持续疼痛，原因之一是软组织（特别是髂腰肌肌腱）撞击替代关节，这可能发生在约5%的病例中。有效的治疗通常是进一步手术，包括髂腰肌肌腱的松解或切除，单独或结合重新定位髋关节置换杯以减少撞击。一些证据表明髋臼杯的尺寸和位置、个体患者的骨骼解剖结构和姿势以及有症状的腰大肌撞击之间存在联系。本研究的目的是确定在给定个体的解剖结构和姿势的情况下，如何放置髋臼部件以避免腰大肌撞击。本项目由一家主要的植入物制造商共同资助，并将解决与临床医生和行业相关的问题，以确保所有患者的髋关节置换手术的结果都是最佳的。此外，该项目将由一名骨科医生共同监督，以提供临床观点。该项目将涉及表征一系列受试者中与腰大肌撞击和姿势相关的骨和软组织解剖结构（使用尸体和成像设备）之间的关系，然后开发一种新的计算模型，以定义腰大肌肌腱的缠绕路径，用于预测撞击。将有机会比较表征和建模与髋关节置换术后症状性腰大肌撞击患者的现有临床数据集。项目结果将为不同患者的部件选择和位置提供手术建议的证据，以避免腰大肌撞击。

Total hip replacement (THR) is a successful operation but the number of devices requiring revision is continuing to rise. Up to 40% of patients report persistent pain after their surgery, and a cause is soft tissue impinging (specifically the iliopsoas tendon) against the replaced joint which can occur in around 5% of cases. Effective treatment is usually further surgery, consisting of release or resection of the iliopsoas tendon, alone or in combination with re-positioning the hip replacement cup to reduce the impingement. Some evidence suggests that there is a link between cup size and position, an individual patient's bony anatomy and posture, and symptomatic psoas impingement.The aims of this study are to determine how an acetabular component can be positioned to avoid psoas impingement, given the anatomy and posture of an individual.This project is co-funded by a major implant manufacturer, and will address an issue of relevance to both clinicians and industry to ensure the outcomes of hip replacement surgery for all patients are optimal. Additionally, the project will be co-supervised by an orthopaedic surgeon to provide a clinical perspective.The project will involve characterising the relationship between bony and soft tissue anatomy (using cadaveric and imaging facilities) relating to psoas impingement and posture in a range of subjects, then developing a new computational model to define the wrapping path of the psoas tendon for use in predicting impingement. There will be opportunities to compare characterisation and modelling with an existing clinical data set of patients with symptomatic psoas impingement after hip replacement.The project outcomes will provide evidence for surgical recommendations on component selection and position for different patients to avoid psoas impingement.