A great paper on Hallux Limits

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Don't let the title fool or dissuade you. 

Here is a great paper to support the post earlier this week on hallux limitus. 

Plantar pressure distribution in older people with osteoarthritis of the first metatarsophalangeal joint (hallux limitus/rigidus)

No surprise that the study found folks with osteoarthritis of the the 1st MPJ had greater maximum force and peak pressures under the hallux as well as the lesser toe than controls. 

BUT here is one of the gems from the study: " However, the plantar pressure changes observed in this study can be explained using the concept of high- and low-gear push off described by Bojson-Moller. This model suggests that there are two metatarsal axes through which propulsion may occur; a transverse axis connecting the first to second metatarsal heads, and an oblique axis connecting the second to fifth metatarsal heads. In the presence of normal first MPJ motion, a ‘‘high-gear’’ push- off occurs through the transverse metatarsal axis, resulting in an efficient transfer of bodyweight. In the presence of restricted first MPJ motion, propulsion through the transverse axis is not possible. Subsequently, a ‘‘low-gear’’ push-off occurs through the oblique axis, which subjects the lateral forefoot and toes to increased loading and results in hyperextension of the interphalangeal joint of the hallux prior to toe-off."

Zammit, G. V., Menz, H. B., Munteanu, S. E. and Landorf, K. B. (2008), Plantar pressure distribution in older people with osteoarthritis of the first metatarsophalangeal joint (hallux limitus/rigidus). J. Orthop. Res., 26: 1665–1669. doi:10.1002/jor.20700.    

link to FREE FULL TEXT: http://onlinelibrary.wiley.com/doi/10.1002/jor.20700/epdf

 

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How much does your Hallux Extend?

Last week, on Mondays post, we introduced potential areas for power leaks.

The common areas for leaks are:

  • great toe dorsiflexion
  • loss of ankle rocker
  • loss of knee flexion/extension
  • loss of hip extension
  • loss of balance/ proprioception


let’s take a look at a video of the 1st one:

Power leak 1: Great Toe Dorsiflexion

The big toe needs to extend AT LEAST 40 degrees and CLOSER TO 60 degrees for normal walking and running gait. If you do not have that available range of motion, then you will need to “borrow” it from somewhere else.

Common compensations include:

  • externally rotating the foot and coming off the inside of the great toe. this often causes a callus at the medial aspect of the toe. This places the foot in more pronation (plantar flexion, eversion and abduction) so it is a poorer lever.
  • internally rotating the foot and coming off the outside of the foot. This places the foot in more supination ( dorsiflexion, inversion and adduction) and it is therefore a more rigid lever. This often causes tripping or stumbling because of a lack of adequate dorsiflexion of the foot.
  • lifting the foot off the ground and avoiding toe off at terminal stance phase
  • abbreviating the step length to accommodate the amount of available great toe dorsiflexion.

Are YOU losing power? Tune in here for more tips on this series in the coming weeks!

The Gait Guys. Increasing your gait literacy with each and every post.