Runners' foot injuries could be due to ill-fitting shoes

Researchers will survey runners in the Oct. 7 Bank of America Chicago Marathon who seek treatment for foot and ankle injuries in the podiatry tent.

Researchers will ask runners their chief complaint for entering the podiatry tent, and measure the runners' feet and shoe sizes. Researchers will record how many marathons each runner has completed and the brand and style of the runner's shoes and socks.

Runners also will be asked to estimate how many miles they have put on their shoes. (Experts generally recommend replacing shoes after about 500 miles, but some runners keep their shoes much longer.) Runners who use minimalist shoes that mimic barefoot running will not be included in the study.

Previous studies have examined shoe fit and foot injuries in special populations such as in diabetic patients and the elderly. The Loyola study is the first to examine the association between shoe fit and foot injuries in marathon runners, said Loyola podiatrist Katherine Dux, DPM, principal investigator of the study.

Nearly every year since 2003, Dux has volunteered her time to treat Chicago marathon runners in the podiatry tent. (The exception was 2010, when she ran the marathon herself.) Usually, between 200 and 400 runners seek treatment for such injuries as blisters, toenail injuries, plantar fasciitis (heel pain), foot stress fractures and sprained ankles. "Most of these injuries are related to improper shoes, socks or training," Dux said.

Shoes that are either too small or too large can cause injuries. Many runners buy shoes that are a half-a-size or a full size too large, to allow for foot swelling during running and to make room for their orthotics.

Dux advises that when buying running shoes, wear your normal running socks and orthotics, and buy late in the day after your feet have become swollen from walking around all day.

Dux is an instructor in the Division of Podiatry, Department of Orthopaedic Surgery and Rehabilitation at Loyola University Chicago Stritch School of Medicine. Co-investigators in the study are Loyola podiatry residents Bryce Paschold, DPM, and Natalie Domek, DPM; and Jeffrey Baker, DPM, and Stephen Weinberg, DPM of the Weil Foot and Ankle Institute.