The overall goal of this diagnostic study is to define a standardized evidence-based examination procedure to assess ankle dorsiflexion with the knee extended and flexed. As there's no standardized test to assess ankle dorsiflexion, this examination method can help to define physiological and pathological values of ankle dorsiflexion. Clinicians will then be able to identify patients with impaired ankle dorsiflexion, which is the root of various pathologies to the foot and ankle.
The main advantage of this technique is that it is a standardized evidence-based diagnostic approach. We first had the idea of this study when review literature on impaired ankle dorsiflexion. Many of the existing examination protocols vary significantly, therefore we aim to define a more standardized test to assess impaired ankle dorsiflexion.
The visual demonstration of this examination technique is very beneficial, as it shows all of the key elements of this procedure in great detail.Mrs. Alena Sint is a member of our foot and ankle research group, and will help us to present the examination procedure. Begin by asking the subject to remove footwear and any clothing covering the legs.
Have two investigators perform the measurement. One conducting the test, and the other measuring the degree of ankle dorsiflexion. Place the subject in a supine position on the examination couch.
Mark the axis of the fibula by drawing a line connecting the center of the distal fibula at five centimeters and 15 centimeters above the tip of the distal fibula. Then have the first investigator place one hand at the level of the subtalar joint to ensure a neutral pronation supination position of the rear foot. And place the other hand around the mid-foot.
Note that one hand stabilizes the subtalar joint and the other hand stabilizes the talonavicular joint, and applies force on the plantar aspect of the forefoot. To achieve maximum ankle dorsiflexion, ensure that the knee is fully extended. Next have the second investigator perform the measurement of the ankle dorsiflexion using a goniometer.
Place one arm of the goniometer connecting the start and end point of the previously-marked axis of the fibula and align the other arm with the plantar aspect of the foot. Note this result on the documentation sheet. Then have the subject flex their knee 90 degrees and repeat this measurement procedure.
Finally, repeat this entire procedure for the contralateral side. Note these results on the documentation sheet. Begin by asking the subject to stand opposite a wall.
Ask the subject to get into a lunge position with the leg to be measured being the rear leg. Help the subject place their rear foot centered on the previously-marked line. Ensure that the heel and second toe of the rear leg are centered on the line.
Have the subject hold on to the wall to stabilize the stance. Then ask the subject to fully extend their rear leg. Ensure that the knee is fully extended.
Next have the subject move the hips toward the wall just before the heel of the rear leg lifts off the ground. The investigator has to ensure that the heel has not lifted off the ground. Place one hand on the dorsal aspect of the subtalar joint to ensure a neutral pronation supination position of the rear foot.
With the other hand, perform the measurement of the ankle dorsiflexion by placing one arm of the goniometer on the floor, and align the other arm along the previously marked axis of the fibula. Note the result on the documentation sheet. Next have the subject move closer to the wall.
Again, have the subject get into the lunge position, where their rear foot is centered on the previously-marked line. Have the subject hold on to the wall to stabilize their stance. Now ask the subject to flex their rear leg and move their hip toward the wall, just before the heel of the rear leg lifts off the ground.
Use the goniometer to ensure that the rear knee is flexed at least 20 degrees. Then place one hand on the dorsal aspect of the subtalar joint to ensure a neutral pronation supination position of the rear foot. With the other hand, perform the measurement of the ankle dorsiflexion in the same manner as previously measured.
Note the result. Repeat all steps for the contralateral side. Review the ankle dorsiflexion data on the documentation sheet, based on the subject's symptomatic side.
Identify whether ankle dorsiflexion with the knee extended is less than 10 degrees on the symptomatic side. Then compare ADF with the knee extended and flexed. If ADF is greater than 10 degrees, compare ankle dorsiflexion with the knee extended between both legs.
Consider musculus gastrocnemius tightness to be a possible cause, if ankle dorsiflexion is reduced on the symptomatic compared to the non-symptomatic side. This protocol demonstrates a standardized examination protocol for musculus gastrocnemius tightness, using a Non-weightbearing and a Weightbearing technique. The mean Ankle dorsiflexion of each step of Knee flexion indicated significantly higher values for Weightbearing measurements, compared to Non weightbearing measurements.
Here, the difference of ADF between each step of knee flexion is shown. Significant differences were only observed between full knee extension and 20 degrees of knee flexion. After watching this video, you should have a good understanding of how to conduct this standardized examination to assess ankle dorsiflexion with the knee extended and flexed.
Based on this, one can diagnose impaired ankle dorsiflexion as well as musculus gastrocnemius tightness. Once internalized, this technique can be done in a couple of minutes. While performing this procedure, it's important to keep the hind foot in neutral position, to stabilize the talonavicular joint and to ensure the appropriate knee position.
This technique will pave the way for researchers in the field of foot and ankle disorders to finally agree on a consistent definition for physiological and pathological values of ankle dorsiflexion.
