Knee Pain Reduction Using a Shock-Absorbing Sole

Background: The biomechanics of the foot and leg are responsible for shock absorption during human gait. Lack of shock absorption is known to be a key component of knee pain. This study compares a new model of shoe sole with a built-in modification intended to absorb shock with a traditional sole shoe to examine whether shoe design modifications can help alleviate knee pain. Methods: A double-blind randomized controlled study was performed. Fifty-two adults with overuse symptoms of knee pain, either unilateral or bilateral, were enrolled and randomly assigned to use the intervention sole or the traditional sole shoes. For 5 weeks, participants wore either the shoe with the intervention sole or the shoe with the traditional sole, rating their knee pain on a 10-point visual analog scale at study onset, midway, and study completion. Results: After 5 weeks, participants using the intervention sole shoe reported an average reduction in knee pain of 85%, significantly better than participants using the traditional sole shoe (P < .001), whose average pain scores increased. Positive effects on back and foot pain were also observed in those with the intervention sole shoe compared with the traditional sole shoe. Conclusions: The intervention shock-absorbing sole represents an approach to midsole and outsole construction that can potentially increase shock absorption and decrease knee pain during prolonged standing and walking. (J Am Podiatr Med Assoc 112(1), 2022).