The study
This was a randomised controlled trial in 75 people with rheumatoid arthritis and foot pain, split into three groups over six weeks: a control group, an underwater ultrasound group, and a group that received underwater ultrasound plus custom-made insoles.
Alongside the usual pain and function measures, they tracked plantar pressure distribution.
What they found
The insoles did what insoles are mechanically good at: they changed the plantar pressure distribution, redistributing load across the foot. What they did not do was produce a clearly superior result on the pain and function measures compared with the other groups. So the device shifted the loading, but in this trial that did not translate into a stand-out improvement in symptoms.
What it means for your practice
Custom insoles in rheumatoid arthritis are most defensible for load redistribution and pressure management, which is a real and worthwhile mechanical job, rather than as a promise of broad pain relief or functional improvement on their own.
That should shape how you set expectations with these patients. It is reasonable and consistent with the evidence to use insoles to offload painful or vulnerable areas of a rheumatoid foot and to manage pressure, and that has real value, particularly where there is a risk of tissue damage. It is overpromising to tell a patient that insoles alone will markedly reduce their pain or restore function, because this trial did not find that.
In practice that means positioning insoles as one part of a broader rheumatoid foot plan, working alongside the medical management of the disease, footwear and monitoring, with the insole earning its place specifically as a pressure-management tool.
Bottom line
In rheumatoid arthritis foot pain, custom insoles reliably change how pressure is distributed but did not clearly outperform the other options on pain and function. Use them for offloading and pressure management, and set expectations accordingly rather than promising broad symptom relief.