Ethnic Minorities Less Likely to Undergo TJA, National Joint Registry Study Shows

    Data from the National Joint Registry for England, Wales, Northern Ireland, and the Isle of Man (NJR) show that black and Asian ethnic minorities in the UK are less likely than whites to undergo hip or knee replacement surgery.

    The study, published online by Osteoarthritis and Cartilage, is first large-scale study of ethnicity and joint replacement in the UK, covering more than 640,000 patients.

    The researchers compared recorded numbers with expected numbers of first-time hip and knee replacement procedures by ethnicity. Their findings showed that black and Asian populations were undergoing fewer procedures than expected, with a far more significant difference for hip replacement than for knee replacement procedures:

    Blacks were one third as likely to receive a hip replacement and Asian people one fifth as likely compared with white people.

    For knee replacement, blacks were two thirds as likely and Asians just over four fifths as likely to undergo the procedure compared with Whites.

    The study also showed gender differences, with non-white men significantly less likely to undergo joint replacement surgery than non-white women.

    In addition, the findings reinforced existing research showing that patients from ethnic minority groups having either hip or knee replacement for osteoarthritis were more likely to be living in poorer areas.

    “There are many possible explanations for why ethnic minorities are undergoing fewer than expected joint replacement operations, and it is likely a combination of different factors,” said Ashley Blom, MB,ChB(CapeT), FRCS, professor of orthopaedic surgery at the University of Bristol, who led the team that undertook the study on behalf of the National Joint Registry.

    “One possible explanation could be patient willingness to undergo surgery amongst the different ethnic groups examined. This is often shaped by cultural factors, doctor-patient communication, and even patient trust in the healthcare system,” he said

    “Secondly, osteoarthritis of the hip is slightly less common amongst black and Asian people, and this may partially explain the differences.”

    Professor Blom added, “It is also interesting to note the gender differences in rates of knee replacement, with black and Asian males much less likely to undergo joint replacement than black and Asian females. These initial observations require further investigation.”

    The study also investigated differences among the ethnic groups in the types of implants and fixation methods used.

    The researchers noted that there was “a surprising difference” in the higher use of more expensive, uncemented hip prostheses for ethnic minority patients, in particular amongst black minority groups.  

    “Patients from an ethnic minority background are more likely to have their joint replacement at hospitals [that] are higher users of uncemented hips,” Professor Blom said.

    “This means that the hospital in which a patient is operated on is a major determinant of the differences in hip replacement fixation method, as large, urban hospitals tend to serve a greater proportion of ethnic minority patients.”

    He added, “At this stage, we remain unclear as to the importance of each possible reason as to why there are such differences in the rates of joint replacement in different ethnic groups, and in the types of implant and fixation used.

    “Whether this reflects differences in clinical need or unequal access to treatment requires further investigation.”


    Smith MC, Ben-Shlomo Y, Dieppe P, et al. Rates of hip and knee joint replacement amongst different ethnic groups in England: an analysis of National Joint Registry data. Osteoarthritis and Cartilage. 2017;25(4):448-54.