The relationship between clinical outcomes and gait biomechanics in individuals with plantar fasciitis.

Measurements were taken at one point in time, so the study can show that measures go together but not that changing one changes another. The subgroups were small (19 recent-onset, 23 chronic) and many correlation tests were run without adjusting for multiple comparisons; the authors themselves call the relationships preliminary and hypothesis-generating. Everyone had mild to moderate pain (3 to 7 out of 10), so the results say nothing about people with severe pain. Only the more painful limb was analysed and most participants had symptoms in both feet, which the authors note may affect walking strategies differently. Almost all participants were women (40 of 42), and everyone was recruited at a single centre in Thailand. The two predictors explained 28% of the variation in walking speed, so most of what determines walking speed was not measured here.

The authors declare no conflict of interest. The work was partly supported by a PhD scholarship from the 60th Year Supreme Reign of His Majesty King Bhumibol Adulyadej, Faculty of Physical Therapy, Mahidol University. No commercial sponsor is named.

Do not read this as evidence that stretching the calf or training balance will make someone walk faster. Measurements were taken at one point in time, so the study shows only that calf length and balance go together with walking speed, not that improving them changes it.