Patients with excessive pronation and chronic foot pain experienced significant pain reduction when assigned to standard intervention, custom-made insole, exercise therapy or a combination of insole and exercise therapy, according to recently published study results.
“There is a lack of evidence regarding the treatment of patients with lower extremity injuries related to excessive pronation in order to support professional evidence-based treatment decisions. So far the effect of exercise therapy has not been sufficiently investigated as a treatment modality for patients with overuse injuries, even though multiple studies indicate a reduction in strength and MEG [magnetoencephalographic] amplitude in the muscles responsible for maintaining a neutral foot posture,” the researchers wrote. “Consequently the aim of this study was to investigate the effect of exercise and insoles to patients with excessive pronation and chronic pain conditions in the foot at 1-year follow-up.”
Foot pain assessment
Eighty participants recruited from the orthopaedic outpatient clinical at Aalborg Hospital, Denmark, or from orthopaedic specialists in the local community were randomly assigned to a standard intervention group (SI), a custom-made insole group (IG), an exercise therapy group (EG) and a combined insole and exercise therapy group (IEG). The SI group received a folder on overuse injuries and exercise, and were advised not to buy or use insoles at any time without consulting the project leader. Participants in the IG and IEG groups received custom insoles made by an orthotist, and intervention for the EG and IEG group consisted of individual exercise guided by a physiotherapist, 30 minutes twice a week for 12 weeks.
Image: © Shutterstock
Outcome measures were assessed at baseline, 4 and 12 months, and included pain reported during walking, resting and running. Static and dynamic foot postures were measured as calcaneal angle, navicular drift, drop and height.
Overall, all groups reported significant pain reduction during walking at 4 months and 12 months of follow-up and no differences were found between groups in any of the pain parameters. At baseline and 12 months, researchers observed weak correlations between changes in pain and foot postures. Navicular drift decreased among participants in the EG and IEG groups at 4 months follow-up, significantly changing static foot posture. However, the changes were present only in the IEG group at 12 months. A significant difference was also found in navicular drift between SI and IEG groups at 4 months follow-up, as well as between IEG and both SI and IG groups at 12 months in favor of IEG, according to study results.
Potential biases
Throughout the study, the researchers recognized several biases that should be considered during analysis. For example, some of the participants in the SI group and the EG group used insoles after the 4-month intervention period, which may have underestimated a possible follow-up effect. Also, the number of participants in each group that had decided to wear insoles was not systematically recorded, so the results at 12 months should be viewed with caution, they wrote.
The researchers wrote that the concept of “aligning the skeleton” with shoes, inserts and orthoses should be reconsidered in a clinical setting, given that only small, non-systematic and subject-specific changes of foot and leg movement can be observed. The lack of noted kinematic changes and the limited effect of insoles on pain during walking suggest that “changes in forces or ‘aligning the skeleton’ are of less clinical importance.
“The results at 12 months follow-up should be viewed with caution due to the risk of cross-contamination,” the researchers concluded. “None of the treatment 
modalities seem to be superior with the number of patients available in this study and therefore different approaches seem to have an effect in treating orthopaedic outpatients in daily clinical practice.” — by Casey Murphy
Disclosure: The researchers had no relevant financial disclosures.
