Septic arthritis is a potential catastrophic complication of intra-articular steroid injection. There is lack of evidence regarding the precautions that should be taken to avoid such a complication, as well as how often it is encountered. The aim of this study was to evaluate the antiseptic precautions taken during intra-articular steroid injection of the knee in the United Kingdom (UK), and estimate how often septic arthritis is encountered by health professionals in the UK following steroid injection of the knee. A questionnaire was posted to 100 orthopaedic surgeons, 100 rheumatologists and 50 general practitioners (GPs), asking them about the cases of septic arthritis following intra-articular steroid injection of the knee that they encountered during their practice and the precautions they take when injecting knees. The response rate was 76.4%; 57.6% of the respondents used alcohol swabs to clean the skin, and the remaining 42.4% used chlorhexidine or Betadine. Only 16.3% used sterile towels to isolate the injection site. There were 32.5% of respondents who routinely used sterile gloves when injecting, and a total of 46.6% used either sterile or non-sterile gloves. Also, 91.1% changed needles between drawing the steroid and injecting it into the joint. Only 24 respondents (12.6%) had encountered septic arthritis after steroid injection of the knee (18 once, 3 twice, 2 three times, 1 several times). We concluded that septic arthritis post intra-articular steroid injection of the knee is probably rare. There is a wide variation in the precautions taken to avoid such a complication. However, the trend seems to be towards minimal use of antiseptic techniques. Further large prospective studies are needed to determine how frequently septic arthritis of the knee is encountered post steroid injection, and the exact precautions that should be taken to avoid it.