Dec 7

Written by: Larry Huppin, DPM
12/7/2009 12:23 PM

I had a question from a client this morning regarding a patient with hallux limitus. They wanted to know if they should include a first ray or first metatarsal cut-out on the orthosis.  A first ray cut-out is shown below on the left and a first metatarsal cut-out on the right.

The idea behind a first ray/first metatarsal cut-out is to cut away the medial distal portion of the plate of the orthosis in order to let the first ray plantarflex more effectively. When the first ray is allowed to plantarflex the windlass mechanism functions normally and compression is reduced in the first MPJ and tension is reduced in the plantar fascia. This would seem to be a good idea. So why do we rarely recommend it?

Primarily, we don’t recommend 1st ray cut-outs and 1st metatarsal cut-outs very often because there are better ways that an orthosis can encourage plantarflexion of the first ray and by narrowing the front edge of the orthosis, the first ray cut-out destabilizes the orthosis. I’ll list those methods below and then you can use the links to read further about them elsewhere on this website. If you are a ProLab client, feel free to call one of our medical consultants to discuss this further.

How to encourage the first ray to plantarflex:

• Plantarflex the first ray when casting the foot
• Prescribe a minimum cast fill
• Invert the positive cast a few degrees
• Prescribe a reverse Morton’s extension

When the above do not provide adequate relief, then I will sometimes try the first metatarsal cut-out. But I never include it in my initial prescription.

We encourage you to read the following information on hallux limitus as it address this issue:

• Pathology Specific Orthosis for Hallux Limitus
• Understanding the Biomechanical Effects of Hallux Limitus by Paul Scherer
• Scherer PR, Sanders J, Eldredge D, et al. Effect of functional foot orthoses on first metatarsophalangeal joint dorsiflexion in stance and gait, J Am Podiatr Med Assoc 96(6):474, 2006

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