BACKGROUND The Dynamic Locking Blade Plate (DLBP) was recently introduced for fixation of displaced femoral neck fractures (FNF) and has been well received. Although the results of this implant in young patients are promising, the DLBP has not yet been compared to a standard device such as the Dynamic Hip Screw (DHS). The aim of this study is to compare the clinical outcome and costs of displaced FNF treated with internal fixation by means of either the DLBP or the DHS in patients up to 65 years of age. We hypothesize that the DLBP is superior compared to the DHS in terms of revision surgery rate, union rate, incidence of avascular necrosis and implant related failure. METHODS The DEFENDD (DisplacEd Femoral Neck fractures Dlbp versus Dhs) trial is a multicentre randomized controlled trial that will include 266 patients of 18-65 years with a displaced FNF. Patients will be randomized to receive either a DLBP or a DHS with a 1:1 allocation using a random block size, stratified for centre. Clinical follow up will last 1 year and questionnaires will be obtained up to 2 years. The main outcome parameter is the incidence of revision surgery within 1 year, due to either non-union, avascular necrosis (AVN) or cut out of the implant. Secondary study parameters are the incidence of avascular necrosis, non-union, (implant related) complications, functional outcome, elective removal of the implant and health-related quality of life and costs. DISCUSSION The outcome of the DEFENDD trial will provide high-level evidence of which implant is favourable for the treatment of femoral neck fractures in young patients (≤65 years). TRIAL REGISTRATION Netherlands Trial Register, NL7300 Registration date 25-09-2018.

中文翻译：

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DEFENDD试验的研究方案：65岁及以下患者的动态锁定刀片板（DLBP）与动态髋螺钉（DHS）进行RCT治疗股骨颈移位性骨折。

背景技术动态锁定刀片板（DLBP）最近被引入用于固定移位的股骨颈骨折（FNF），并且已经受到广泛好评。尽管这种植入物在年轻患者中的结果令人鼓舞，但尚未将DLBP与诸如动态髋螺钉（DHS）之类的标准设备进行比较。这项研究的目的是比较使用DLBP或DHS进行内固定的置换FNF在65岁以下患者中的临床结局和费用。我们假设在翻修手术率，联合率，无血管坏死的发生率和与植入物相关的衰竭方面，DLBP优于DHS。方法防御性（股骨颈移位性骨折Dlbp与Dhs）试验是一项多中心随机对照试验，将包括266例18-65岁的FNF移位患者。患者将被随机分配以随机分组大小接受1：1分配的DLBP或DHS，并按中心分层。临床随访将持续1年，并且问卷调查将获得长达2年的时间。主要结局参数是由于不愈合，无血管坏死（AVN）或切除植入物而导致的一年内翻修手术的发生率。次要研究参数是无血管坏死的发生率，不愈合，（与植入物有关的）并发症，功能结局，选择性摘除植入物以及与健康有关的生活质量和费用。讨论DEFENDD试验的结果将提供高水平的证据，表明哪种植入物有利于治疗年轻患者（≤65岁）的股骨颈骨折。试用注册荷兰试用注册，NL7300注册日期25-09-2018。