The Mighty Extensor Digitorum Longus (EDL): a pedograph case.
We have long been promoting appropriate function of the long extensors of the toes (predominantly the EDL, but also the Extensor hallucis longus) here, in our practices, our lectures, on Youtube, in our book……You get the idea. Lets tale a closer look at this muscle (picture left above)
The EDL has a proximal attachment in the lower leg up at the condyle of the tibia, proximal fibula, the interosseus membrane, and the connective tissues between the muscles. It travels down the leg, under the extensor retinaculum and attach to the base of the distal phalanges of toes 2-4. These muscles act from initial contact (to help eccentrically lower the foot to the ground), loading response (to continue to lower the foot slow or attenuate pronation), midstance and terminal stance (to provide compression of the metatarsal phalangeal and interphalangeal joints, and to offset the long flexors (which are often overactive, due to flexor dominance)).
What does it look like when the long extensors don’t work so well? Have a look at the pedograph on the right. what do we see? First we notice the lack of printing under the head of the 1st metatarsal and increased printing of the second metatrsal head. Looks like this individual has an uncompensated forefoot varus (cannot get the head of the 1st metatarsal to the ground, and thus a weak medial tripod). Next we see increased printing of the distal phalanges of digits 2-4. Looks like the long flexors are dominant, which means the long extensors are inhibited. What about the lack of printing of the 5th toe? I thought the flexors were overactive? They are, but due to the forfoot varus, the foot is tipped to the inside and the 5th barely contacts the ground!
How do you fix this?
Help make a better foot tripod using the toe wave, tripod standing and extensor hallucis brevis exercises. Make sure the articulations are mobile with joint mobilization, manipulation and massage. Make sure the knee and hip are functioning appropriately. Give the client lots of homework and put them in footwear that will allow the foot to function better (a less rigid, less ramp delta shoe). As a last resort, if they cannot make an adequate tripod (because of lack of motivation or anatomical constraints), use a foot leveling orthotic.
Ivo and Shawn. Two guys, making a difference, every day.
all material copyright 2012 The Homunculus Group/The Gait Guys. All rights reserved. If you rip off our stuff, you will be plagued with foot fungus and bunions for all your days.