Abstract. Objective. Short-stem total hip arthroplasty (THA) aims to preserve the proximal bone stock for future revisions, so that the first revision should resemble a primary intervention rather than a revision. This study aimed to compare the clinical and radiological outcomes in revision THA after failed short stem versus after failed conventional stem THA. Methods. This study included forty-five patients with revision THA divided into three groups (15 each); group A: revision after short stem, group B: revision after conventional cementless stem and group C revision after conventional cemented stem. The studied groups were compared regarding 31 variables including demographic data, details of the primary and revision procedures, postoperative radiological subsidence, hospital stay, time for full weight bearing (FWB), preoperative and postoperative clinical scores. Results. Early stem subsidence (40%) was the main indication of revision in group A compared to peri-prosthetic femoral fractures (PFFs) (73.3%) and aseptic loosening (53.3%) in group B and C respectively (P=0.021). The mean time to revision was significantly shorter in group A (15 months) compared to 95.33 and 189.40 months in group B and C respectively. (P=0.005). Sixty % (9 patients) in group A were revised in the first year. The mean operative time, blood loss, postoperative blood transfusion and hospital stay were significantly lower in group A compared to group B and C (P<0.001, <0.001, 0.002 and 0.001 respectively). Revisions in group A were performed using either short stems (13.3%) or conventional stems (86.7%) whilst 80% of patients needed long stems and 20% of patients needed conventional stems in group B and C (P<0.001). The mean postoperative Harris Hip Score (HHS) at the latest follow up was 87.07, 87.53 and 85.47 in group A, B and C respectively. All PFFS had excellent results according to Beal's and Tower's criteria; all fractures healed and the implants were stable. Conclusion. The most common cause of failure of short stems is early stem subsidence. Short stem THA has specific indications and patient selection is very crucial. Preoperative templating for short stems and a detailed analysis of the individual patient anatomy in anteroposterior and lateral views are mandatory to predict the correct implant size more accurately. The use of intraoperative imaging can verify the sizing, implant position, and sufficient contact with the lateral cortex. Revision of short stem THA resembled the primary THA. If a standard implant can be used in a surgical revision instead of a longer revision stem, this can be considered as an advantage for the hip arthroplasty treatment concept. However, this only applies if the longevity of the first treatment with a short stem is comparable with that of a standard stem. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Total hip arthroplasty is well established as a successful treatment modality for end stage arthritis, with a variety of components currently available. However, utilising traditional stemmed implants in patients with distorted proximal femoral geometry can be technically challenging with increased risk of complications. We present seven patients with distorted proximal femoral anatomy or failed hip arthroplasty in whom a technically challenging primary or revision operation was simplified by use of a Proxima stem. This is a short, stemless, metaphyseal loading implant with a pronounced lateral flare. At twelve months follow up there have been no complications with average improvement in Oxford and Harris scores of forty and forty-nine respectively. Radiological analysis shows all stems to be stable and well fixed. Designed primarily as a bone conserving implant for primary hip arthroplasty we propose that the Proxima prosthesis also be considered in cases where a conventional stemmed implant may not be suitable due to challenging proximal femoral anatomy. The use of the stemless Proxima implant provided a simple solution in seven difficult and potentially lengthy complex primary and revision hip arthroplasties with gratifying clinical and radiological outcomes