• Magnetic Resonance Imaging
• Disease Activity
• Inflammation

We thank Pan et al for their initial paper1 and subsequent response to our comment.2–4 We agree with the proposed biphasic role of the infrapatellar fat pad (IPFP). Although there is evidence to support a change of practice towards preservation of the IPFP,5 we agree that there should not be a ‘one shoe fits all approach’, there being cases in which benefit may be derived from IPFP resection.

A considered approach offered by Han et al 4 involves using screening MRIs to identify IPFP signal intensity alterations and a subsequent indication for resection. However, this technique is not yet validated with high-quality randomised controlled trials (RCTs).4 An alternative solution proposed by Sekiya et al 6 may be the use of postarthroplasty arthroscopic IPFP debridement.

Currently the incidence of knee pain post total knee arthroplasty (TKA) is low, with approximately 10% of patients reporting mild to moderate pain7 ,8 and 4.8% reporting severe pain.6 The study by Sekiya et al 6 found that of the 4.8% of patients with severe knee pain, a significant proportion had scar tissue between the IPFP and the tibiofemoral space, impinging the femorotibial joint. Following arthroscopic resection of this scar tissue, 63% of the patients reporting severe pain were now pain free and a further 23% had their pain at least halved.6

This suggests that less than 2% of patients will report severe knee pain post TKA if the IPFP is preserved and arthroscopic debridement is performed as required. However, IPFP screening as proposed by Han et al has the potential to reduce reoperation and perhaps reduce morbidity beyond this. Consequently, we eagerly await RCTs investigating its use and the possibility of reducing severe pain post TKA to less than 1%.