1st MTP Pain? The Biomechanics of the Big Toe...

Remember the rockers? We have done a series on this in the past. Remember there are three: heel, ankle and forefoot. We are going to concentrate on the forefoot today.

As a reminder, forefoot rocker occurs at the 1st metatarsal phalangeal joint (big toe knuckle) as the tibia progresses over the forefoot during forward movement. You NEED 50 degrees to do this competently; you SHOULD have 65 degrees. When you don’t, you have a condition called hallux limitus. This could be from a number of reasons, from overpronation in the mid foot, to a bunion, to faulty firing patterns of the muscles which help to descend the 1st ray (the extensor hallucinations brevis, the peroneus longs and the short flexors off the toes). Pretty much, ANYTHING that causes a dorsal and posterior shift of the 1st MTP axis will cause limited forefoot rocker.

So, the question is, “Do you know where 1st 1st MTP pain may be coming from? How familiar are you with the mechanics of that joint?”

Take a few minutes to review it in this video with Dr Ivo Waerlop of The Gait Guys.

#gait, #gaitanalysis, #1stmtp, #forefootrocker, #thegaitguys,

Calf strength, the medial foot tripod, and pain in the great toe

It has become evident that this component, the proper function of the 1st ray complex, is overlooked in some of the clinical world. Hallux joint pain is a difficult one to diagnose and treat at times. The source of pain and dysfunction can seemingly come from anywhere, but the more one understands the complex mechanics of this joint and regionally associate joints, the better clinical results one will achieve.  

One thing that has become recurrently obvious upon the many outside professional referrals that come though my office is the imbalance and/or weakness or endurance impairments in the posterior mechanism in relation to a painful 1st metatarsophalangeal joint (MTP). When I say posterior mechanism I am referring to the gastrocnemius, soleus, peronei, long flexors, and tibialis posterior namely. 

And, let me be clear, putting a theraband under the 1st metatarsal, encouraging your client to drive greater downward purchase of the head of the 1st MET during simulated foot tripod loading, does not necessarily help your client if their 1st MET is slightly more dorsiflexed. Do not be fooled by the flashy rehab guru tricks out there, proper clean function is achieved, not forced. If you have not earned it, you do not own it. 

It is quite simple really. If one does not have balanced function, including skill (motor pattern), endurance or strength of plantarflexion of the ankle, one cannot properly posture the first metatarsal (1st MET) in plantarflexion to sufficiently alter the sesamoid posturing underneath the metatarsal head, to sufficiently engage the unique eccentric axis (and it's necessary shift) of the 1st MTP to enable ample clean hallux dorsiflexion. Furthermore, without all this,  one will not be able to anchor the medial foot tripod properly.  This can lead to pain, functional hallux limitus, hallux rigidus to name a few. And, let me be clear, putting a theraband under the 1st metatarsal, encouraging your client to drive greater purchase of the head of the 1st MET during foot loading, does not necessarily help your client if their 1st MET is slightly more dorsiflexed. Do not be fooled by the flashy rehab guru tricks out there gang, proper clean function is achieved, not forced. 

A simple example might be a runner who fatigues the posterior mechanism in a long run. As the calf fatigues, they lose ample heel rise, thus ample plantarflexion of the 1st MET, thus proper posturing and translation of the sesamoids, thus successful eccentric axis shift, and thus clean dorsiflexion of the 1st MTP joint.  A player in a jumping sport who has less than ample strength of the posterior mechanism can have much the same issue at the resultant toe.  These are just garden variety examples.  But, should be clear that ample skill, endurance and strength (S.E.S.), our favorite mnemonic, of the posterior mechanism is necessary for pain free, functional toe off in the gait cycle or in jumping mechanics. 

If you are not systematically testing for these S.E.S. issues in the posterior mechanism, you are likely missing a major component in the proper posturing of the ankle and foot and thus proper functioning of the first ray complex and thus enabling clean function at the 1st MTP joint.  

(Sidebar rant: My past personal problems at this great toe joint started when a fellow chiropractor pulled on my toe many moons ago, for some random reason. It was the proverbial,  axial distraction "adjustment". The cavitation was heard around the world (the saliva inducing "pop" that fools many into blissful success), and my problems began.  I had painful dysfunction for many years after that for some strange reason, something was damaged but I was too stubborn and stupid to fix my own foot. I eventually remedied the problem through diving deeper into the complex mechanics of this joint and regionally associated areas. For this very intimate reason, it is why I am not one to perform this maneuver or recommend it. If we can be smarter in our understanding, we can be wiser in our interventions. Besides, axial distraction of this joint is not normal function of this joint. If I had a soap box to stand on for this topic, I would tell people to stop doing HVLA manipulations to this joint, mobilizations are more than ample to elicit a joint range response or a neurologic mechanoreceptor response. The more you understand this profoundly complicated and interesting joint, the 1st MTP joint, the more you will understand how to help your client. But, what do I know, I am just a dumb chiropractor, right Joe Rogan :) 

- Shawn Allen, the gait guys

1st MTP Pain?

It may not be a trigger point. In this capsule summary, Dr Ivo discusses an interesting and perhaps revolutionary, theory on trigger point pain that refers to the 1st metatarsal phalangeal articulation. The anatomy of the joint and responsible muscles are also discussed