Empirical support for radiographic review: a follow-up study of total hip arthroplasty

Routine post surgery surveillance of total hip arthroplasty (THA) is widely recommended to identify asymptomatic failure but inclusion of an x-ray adds to service costs. Evidence is needed to support orthopaedic opinion in order to identify what should be included in surveillance. An investigation was conducted to establish whether an x-ray is needed in addition to patient reported outcome measures. One hundred and fifty-four THA had been assessed at 3 years and were reviewed again at 6 to 9 years (mid-term) when radiographic signs of deterioration commonly appear. Data were explored for associations between radiographic changes and changes in the participants' Oxford Hip Score, age, EuroQol 5-D score or comorbidities. Hierarchical multiple regression analysis showed that the number of radiographic changes could not be predicted by any of the other variables. This supports the inclusion of an x-ray in THA surveillance and suggests that the state of the THA cannot be determined by the use of patient reported outcome measures alone. This has implications for future arthroplasty surveillance.