The effect of foot overpronation on Achilles tendon blood supply in healthy male subjects
Karzis K, Kalogeris M, Mandalidis D, Geladas N, Karteroliotis K, & Athanasopoulos S. Scan J Med Sci Sports. 2016; Accepted for publication May 23, 2016. doi: 10.1111/sms.12722
Take Home Message: Participants with rear foot valgus appear to have diminished blood flow to the Achilles in comparison to normal rear foot individuals. More research is needed to determine how we can clinically intervene.
Achilles tendon injuries frequently result in functional limitations and a predisposition to rupturing. Researchers have implicated that blood supply may contribute to the susceptibility of major injury, and that blood supply might be affected by functional foot structure. The authors of this study investigated whether foot alignment affected Achilles tendon blood supply as assessed by Doppler ultrasound. Thirty male participants (15 with rear foot valgus and 15 normal rear foot) had their Achilles tendon blood flow examined by Doppler ultrasound in the non-weight bearing, double stance weight bearing, and single stance weight bearing positions. Participants with overpronation had greater resistance and reduced blood flow than normal feet regardless of stance. In both groups, blood flow was reduced and there was greater resistance as the participants progressed from non-weight bearing, to double, and then single stance weight bearing positions.
These findings are interesting because it supports the “wringing out” mechanism of reduced blood flow as weight bearing increases, and it is exacerbated in individuals with flat feet. It would be interesting to see how the blood flow and resistance would be altered by the use of orthotics or taping. Gait mechanics may also cause issues and changes in blood flow, and this should be analyzed as well. There are many ways to measure blood flow, and a comparison of other blood flow analytics would be interesting as well. The authors did note that there were unsure whether the ultrasound was measuring tendon blood flow or surrounding blood flow. The Achilles tendon is well supplied vascularly, but it remains unknown how we can prevent the ischemic “cut off” or facilitate more blood flow. Tracking patient reported outcomes and how these associate to blood flow measure may help make the connection to when or how we should intervene clinically. Further research is definitely needed in this area. It appears that we should keep a watchful eye on Achilles pain in people with flat feet.
Questions for Discussion: What do you do for people who present with Achilles tendon pain? Are there any other anatomical presentations that you consider to be risky for Achilles tendon issues?
Written by: Nicole Cattano
Reviewed by: Jeffrey Driban