Response to: ‘Effectiveness of low-dose radiation therapy on symptoms in patients with knee osteoarthritis’ by Wu et al

We thank Wu et al for their interest in and encouragement of our randomised studies in which we found no substantial beneficial effect on symptoms and inflammatory signs of low-dose radiation therapy (LDRT) in patients with knee and hand osteoarthritis (OA).1–3 The authors emphasise that our results inevitably force involved clinicians to re-examine the true effectiveness of LDRT on OA in real-world clinical practice. However, they addressed two constructive concerns related to our work, to which we will reply hereby. The first point addresses the heterogeneity of the participants reflecting a real-world population, that is, patients with clinical diagnosis of knee OA after failure of conservative treatment options. Wu et al suggest that randomisation stratified by an objective measure for severity of knee OA (eg, K&L scores) might be preferable to the numeric rating scale for pain to stratify patients. We do not agree on this point because we hypothesised that LDRT would primarily improve clinically relevant OA symptoms including pain and disfunctioning. Accordingly, the …