Foot Pain Worsens Effects of Knee OA
Saturday, March 14, 2015 03:39 PM

Foot pain was common among patients with knee osteoarthritis (OA) and affected both general measures of health and knee-specific symptoms, Australian researchers found.

One in four (25.3%) patients with symptomatic knee OA reported pain in one or both feet/ankles on at least half of the days during the previous month.  "While it is recognized that multiple joint symptoms are both common and disabling in people with knee OA, concurrent foot and knee pain is rarely described and its prevalence is unclear," authors noted.  "The between-group differences suggested these changes are clinically meaningful," the researchers observed.

Possible mechanisms for the development of foot pain in knee OA include varus malalignment and excess pronation.

"Foot pronation (and subsequent pain) could be a compensatory response to OA-related knee pain, whereby the foot pronates to shift the center of pressure ... in an attempt to reduce medial knee load and pain," they explained.

"Increased knee varus may increase the risk of knee OA by increasing medial knee compartmental loading and may also lead to increased foot pronation (contributing to subsequent pathology and pain) to ensure the foot is plantigrade to the ground during the stance phase of walking," they explained.

The Osteoarthritis Initiative is funded by the NIH and private funding from Merck, Novartis, GlaxoSmithKline, and Pfizer.