Incidence rate, risk factors and patient reported outcome in patients with a dislocation following hip hemiarthroplasty after acute femoral neck fracture; a scoping review

Objective The objective of this scoping review of the literature is to find the incidence rate and risk factors for dislocation of hip hemiarthroplasties (HAs) after acute femoral neck fractures (FNFs). Additionally we aim to determine the subjectively reported experience and/or Patient Reported Outcomes (PROs) minimum six months after a dislocation of a hip HA after acute FNF. Introduction The existing literature suggests a dislocation rate of 1 – 12%(1-8), and we aim to evaluate the dislocation rates reported in the literature, and explain the differences in the reportings. Some of the suggested risk factors ranging from surgical approach(1, 5, 6), cognitive impairment(2, 5-8), prosthesis type(4) and uncemented vs cemented implant(3). There are no studies summarizing all risk factors for dislocating the hip HA. The patient’s subjective experience after dislocation of a hip HA after acute FNF is not well known. The literature lacks direct information of the patients’ subjective experience after dislocation of the hip HA after acute FNF. Inclusion criteria Published articles on the incidence of patients with HA, who develop dislocation. Risk factors for dislocation and patient reported outcomes after reposition of dislocation. Register studies, clinical prospective studies and case-control studies will be included. The lower limit for inclusion of a risk factor will be minimum 5 studies that have minimum 10 patients with dislocation(s). Methods This scoping review will be conducted in accordance with the JBI methodology for scoping reviews(9). We will develop a full search strategy for Embase, MEDLINE, PubMed and Cochrane Library. Studies published in English, Swedish, Danish and Norwegian will be included. Studies with other languages will be considered if an appropriate translator is available. The three research questions will be analyzed separately and reported narratively. Despite this being a scoping review, we shall include some risk of bias elements in the analysis.