What influences UK-practising consultant hip surgeons' decision-making about implant fixation? An interview study.

objectivesTo explore the views of UK-based consultant hip surgeons about implant fixation choice and identify factors that inform decision-making about use of cemented, hybrid or uncemented implant fixation when performing total hip replacement in adults aged under 70 years.

designQualitative semistructured interview study. Recruitment was through consultant participation in a national online survey. Purposive sampling was used to ensure a range of implant fixation methods in the final sample. Data were audio recorded, transcribed, anonymised and analysed inductively to generate themes describing influential factors on surgeons' decision-making about fixation choice.

settingUK elective primary total hip arthroplasty. Consultant hip surgeons representing 15 English NHS sites and 2 Scottish Health Boards and one private surgeon took part in a telephone or online interview.

participants20 consultant hip surgeons participated, with consultant-level years in practice ranging from 1 to 25+ years. Seven participants primarily used cemented/hybrid constructs and 13 primarily used uncemented/hybrid constructs in patients aged under 70.

resultsSix themes describing influences on surgeons' decision-making about fixation were identified; 'patient characteristics'; 'patient preferences and implant availability'; 'training and establishing a fixation skillset'; 'formal evidence of outcomes', 'personal outcomes and accumulated clinical experience' and 'surgical speed and cost effectiveness as secondary benefits'. All surgeons described patient characteristics that influenced their decision-making, and the sample contained surgeons who preferred cemented, hybrid and uncemented constructs respectively for young, uncomplicated patients. Bone quality was particularly influential and surgeons used age, comorbidities, activity level and sex as indicators of likely bone quality. Poorer bone was agreed to require a cemented stem; however, cup fixation varied, resulting in use of cemented and hybrid constructs when bone was poor. Varied femoral anatomy, including Dorr C, was commonly deemed to require cemented stems within either cemented or hybrid constructs; dysplastic or sclerotic sockets were deemed to require uncemented cups within either uncemented or hybrid constructs. Patient characteristics such as body mass index, likely need for future revision and risk of infection were influential, but not towards any single fixation method. Many surgeons described being trained into geographical/unit fixation traditions, building skill in two fixation methods rather than three. Good outcomes were undetachable from skilled expertise and therefore continued use of specific fixations was reinforced, particularly when surgeons' personal National Joint Registry outcomes evidenced good performance. Regardless of fixation method preferences, surgeons referred to (at times the same) formal research evidence that supported their fixation choices, as well as their accumulated clinical experience. Increased surgical speed of uncemented components and lower implant cost were not perceived to be key drivers of fixation choice as patient outcomes were prioritised. However, surgical speed was acknowledged as potentially influential in relation to private practice or high volume lists, and costs considered secondarily if good implant outcomes had been established by formal evidence.

conclusionsMultiple factors exert influence on surgeons' decision-making about fixation. Community equipoise was identified among UK hip surgeons relating to which fixation method is superior for young, uncomplicated patients or relative to patient characteristics. TRIAL REGISTRATION NUMBER: ISRCTN14346605.