Inequalities in use of total hip arthroplasty for hip fracture: population based study

Abstract

Objectives: To determine whether the use of total hip arthroplasty (THA) among individuals with a displaced intracapsular fracture of the femoral neck is based on national guidelines or if there are systematic inequalities.

Design: Observational cohort study using the National Hip Fracture Database (NHFD).

Setting: All hospitals that treat adults with hip fractures in England, Wales, and Northern Ireland.

Participants: Patients within the national database (all aged ≥60) who received operative treatment for a non-pathological displaced intracapsular hip fracture from 1 July 2011 to 31 April 2015.

Main outcome measures: Provision of THA to patients considered eligible under criteria published by the National Institute for Health and Care Excellence (NICE).

Results: 114 119 patients with hip fracture were included, 11 683 (10.2%) of whom underwent THA. Of those who satisfied the NICE criteria, 32% (6780) : received a THA. Of patients who underwent THA, 42% (4903) did not satisfy the NICE criteria. A recursive partitioning algorithm found that the NICE eligibility criteria did not optimally explain which patients underwent THA. A model with superior explanatory power drew distinctions that are not supported by NICE, which were an age cut off at 76 and a different ambulation cut off. Among patients who satisfied the NICE eligibility, the use of THA was less likely with higher age (odds ratio 0.88, 95% confidence interval 0.87 to 0.88), worsening abbreviated mental test scores (0.49 (0.41 to 0.58) for normal cognition v borderline cognitive impairment)), worsening American Society of Anesthesiologists score (0.74, 0.66 to 0.84), male sex (0.85, 0.77 to 0.93), worsening ambulatory status (0.32, 0.28 to 0.35 for walking with a stick v independent ambulation), and fifths of worsening socioeconomic area deprivation (0.76 (0.66 to 0.88) for least v most deprived fifth). Patients receiving treatment during the working week were more likely to receive THA than at the weekend (0.90, 0.83 to 0.98).

Conclusions: There are wide disparities in the use of THA among individuals with hip fractures, and compliance with NICE guidance is poor. Patients with higher levels of socioeconomic deprivation and those who require surgery at the weekend were less likely to receive THA. Inconsistent compliance with NICE recommendations means that the optimal treatment for older adults with hip fractures can depend on where and when they present to hospital.

Fig 1 Decision tree for total hip arthroplasty (THA) in displaced intracapsular fractures as per NICE guidelines. AMTS=abbreviated mental test score, ASA=American Society of Anesthesiologists score

Fig 2 Graph illustrating limited improvement in model using optimal tree size of 10 terminal nodes (lowest error), and more pragmatic tree with five nodes

Fig 3 Decision tree for total hip arthroplasty (THA) in displaced intracapsular fractures using recursive partitioning algorithm

Fig 4 Graph illustrating limited improvement in model using optimal tree size of 20 terminal nodes and simplified tree with four nodes

Fig 5 Decision tree using recursive partitioning algorithm to indicate important predictors for total hip arthroplasty (THA) among individuals fulfilling NICE criteria for consideration of THA

Fig 6 Variation in number of total hip arthroplasty (THA) performed within each hospital as proportion of total number of individuals fulfilling NICE guidelines. Only hospitals that contributed >100 NICE eligible patients are included to minimise spurious data (n=96). Each bar represents one hospital