By Jane Lewis
A new pair of walking shoes – with or without modifications designed to unload the medial knee – can result in significant improvements in pain and function for people with knee osteoarthritis, reports an Australian study published in Annals of Internal Medicine.
The study evaluated the efficacy of unloading shoes (shoes with modified midsoles to unload the medial knee) in alleviating knee osteoarthritis symptoms, with the hypothesis that such shoes would confer additional benefit over conventional walking shoes. However, both types of shoes were found to provide improvements in both function and pain.
Speaking to Pain Management Today, Professor David Hunter, consultant rheumatologist at Royal North Shore Hospital, Sydney, and an author on the paper, said while the design of unloading shoes does significantly reduce the force acting cross the knee joint, it does not provide greater pain relief than regular walking shoes. ‘Improving lower limb biomechanics is important, but ultimately it is improvement in symptoms that matters most,’ he said.
In the trial, 164 people aged 50 years or older with medial knee osteoarthritis were recruited from the Melbourne community, and randomly assigned to wear either unloading shoes or conventional walking shoes daily. Both types of shoes were associated with large improvements in function (26% reduction in physical dysfunction) and pain (28% to 30% reduction in pain with walking) at six months compared with baseline, with no significant difference between the two groups. Sensitivity analyses showed that at six months, unloading shoes resulted in clinically important improvements in both outcomes, whereas improvements with conventional shoes were clinically relevant for function but not pain. Approximately half of participants in each group reported globally improved pain or function, the authors reported.
‘At this point it remains unclear what is the best type of shoe that will benefit patients with knee osteoarthritis,’ commented Professor Hunter. ‘Because there is no cure for this disease, it is important that those affected engage in appropriate management including, where appropriate, weight reduction, low impact and strengthening exercise, topical analgesics and the use of assistive devices.’
The authors of an accompanying editorial said the fact that both treatment groups in the study improved ‘highlights the promise of simple biomechanical interventions.’ Although footwear that corrects lower limb malalignment and reduces the pain of knee osteoarthritis ‘would be a major step forward,’ it appears ‘we are not there yet’, they wrote.
Ann Intern Med 2016; 165: doi: 10.7326/M16-0453.
Ann Intern Med 2016; 165: doi: 10.7326/M16-1459.