Dislocation post THA confers a higher risk of re-dislocation (Kotwal et al, 2009). The dual mobility (DM) cup design (1974) was aimed at improving the stability by increasing the femoral head to neck ratio (Cuthbert et al., 2019) combining the ideas of low friction arthroplasty with increased jump distance associated with a big head arthroplasty.

Understand the dislocation rates, rates of aseptic loosening, infection rate and revision rates between the 2 types of constructs to provide current and up-to date evidence.

Medline, pubmed, embase and Cochrane databases were used based on PRISMA guidelines. RevMan software was used for the meta-analysis. Studies (English literature) which used DM construct with atleast 6 months follow-up used as intervention and non DM construct as control were included. 2 independent reviewers conducted the review with a third reviewer in case of difference in opinion regarding eligibility. Primary outcome was dislocation rate and secondary outcome was rate of revision.

564 articles identified out of which 44 articles were screened for full texts and eventually 4 systematic review articles found eligible for the study. Thus, study became a review of systematic reviews. From the 4 systematic reviews, another 35 studies were identified for data extraction and 13 papers were used for meta-analysis. Systematic reviews evaluated, projected an average follow up of 6-8 years with significantly lower dislocation rates for DM cups. The total number of patients undergoing DM cup primary THA were 30,559 with an average age 71 years while the control group consisted of 218,834 patients with an average age of 69 years. DM group had lower rate of dislocation (p < 0.00001), total lower rate of cup revision (p < 0.00001, higher incidence of fracture (p>0.05).

DM THA is a viable alternative for conventional THA. The long-term results of DM cups in primary THA need to be further evaluated using high quality prospective studies and RCTs.

Aim: To establish the surgical treatment of displaced intracapsular femoral neck fractures in hospitals across the United Kingdom.

Methods: The on-call registrars in all 223 hospitals receiving acute orthopaedic admissions in the UK, were interviewed by telephone. Their usual practices were recorded for two groups of patients, active and frail. The proportions of hospitals using the different surgical options were determined.

Results: Despite stereotyped clinical features, management varied between specialists within some hospitals: two or more different methods of treatment were in routine use for active patients in 22% of hospitals, and for frail patients in 27%. The management also varied between hospitals. Overall, for active patients, bipolar hemiarthroplasty was in use in 41%, internal fixation in 37%, unipolar hemiarthroplasty in 32% and total hip replacement in 16% of hospitals. For frail patients either Austin-Moore or Thompson prostheses or both were in use in 94% of hospitals. Where used, Austin-Moore prostheses were uncemented in 93% of hospitals, and Thompson prostheses cemented in 79%. Bipolar prostheses were in use in 8%, and the alternative of internal fixation undertaken for frail patients in 1% of hospitals.

Conclusions: The findings demonstrated a lack of consensus in several aspects of the treatment of displaced intracapsular fractures of the femoral neck, with implications for consideration of best practice, in the UK, and worldwide.