Clinical Application: Measuring Calcaneal Eversion
The importance of calcaneal eversion for proper lower extremity function was covered in last week’s blog. How is calcaneal eversion measured?
The clinician needs to evaluate the ability of the calcaneous to evert in two ways. 1-Structurally 2- Functionally
An athlete/client may have structural eversion without functional eversion but it is not possible to have functional eversion without the availability of structural eversion.
1-Structural Eversion: the range of motion available into calcaneal eversion in the open chain. Measured by the clinician physically(passively) moving the calcaneous or the patient actively attempting to evert the calcaneous. Often measured in prone with the goniometer axis midline of the lower leg and midline of the calcaneous.
2- Functional Eversion: the ability of the calcaneous to evert with the foot on the ground. Not only is the anatomic motion available(structural eversion) but there is sufficient muscle strength/control of the lower extremity and sufficient range of motion available at the other joints in the kinetic chain to allow normal eversion motion to occur.
Measuring calcaneal eversion in weight bearing can utilize the same goniometric axis’. It can be measured with asking the athlete to actively evert in weight bearing. This would be measuring calcaneal eversion in weight bearing but is it truly functional just because it is weight bearing?
Calcaneal eversion measured functionally might look different in any number of ways....depending on the functional task of your athlete/client. The clinician needs to assess eversion by utilizing a test that replicates the athlete’s/client’s activity.
One possibility of infinite options would be a Single leg balance , opposite lower extremity lateral reach. This should drive the calcaneous into eversion on the weight bearing leg.
If eversion is not observed (and you have assessed that structural eversion is present), consider the possible reasons why and this will lead you to other motions to assess.
Some of the possible deficits which would prevent eversion in the example above:
1-inability to fully internally rotate at the weight bearing hip..
2- hip/quad weakness that drives the calcaneous to stay away from everting in order to assist in stabilizing the leg (that which the weak musculature can not do as it should)
3-an arthritic or unstable knee joint that might not want to go in to valgus secondary to pain or instability,(if the knee won’t load , then the calcaneous will stay away from everting..it won’t load either)
For more information on functional rehabilitation and functional evaluation click here.