For those who have ever seen the movie(s) Kill Bill, you may remember the incredibly comedic remark of “wiggle your big toe” after she had escaped from the hospital and was supine in a car. At the time I thought it was ridiculous but she may have been onto something. Clearly proper motion of the hallux is a valuable, even essential piece of efficient locomotion so how does one go about identifying and correcting limitations in first MTP joint range or motion?
While there are a number of suggested assessment protocols for identifying how much range of motion is available at the first MTP joint, there is some debate as to the specificity and sensitivity of a commonly used test. As the function of the hallux is heavily related to that of gait, it is best to attempt to assess the range of motion in a closed chain or artificially closed chain position. Of the available options, I prefer one of two options, however, I’ve recently begun to include both as there really is not a huge time commitment.
Supine Hallux Extension Test
The first test I include as part of my table assessment is an evaluation in supine. To mimic weight bearing, place your thumb underneath the first metatarsal head and passively dorsiflex the hallux. A normal score is in the range of 20-25 degrees, anything below 20 degrees needs to be looked at with a critical eye.
Split Tall Mock Gait
This test is performed by having the client space his feet a predetermined distance apart—generally about stride length—and to actively plantar flex his ankle, which moves the hallux into extension. The range of motion is graded with a goniometer at the joint and relative to the floor. The range of motion should be considered “complete” if the first MTP joint lifts from the floor or the person attempts to change is stride length. I also allow athletes to have a wall in front for balance, but it is important to be sure they are not trying to push themselves into the wall and get a few more degrees of forced ROM.
What must you overcome?
If you have detected a limitation in range of motion, then your next step is to consider what can cause the issue and how best can it be addressed.
There are a number of proposed ideas that may play a role in decreased fist MTP extension, some of which are modifiable and others that are non-modifiable.
In the non-modifiable category; age, gender, acute trauma, long proximal phalanx, square joint articulations, hammer toe, tarsal deformities, and a few others. As these are non-modifiable, if these present a significant enough problem, refer out to someone with better tools in their boxes. Be especially aware of people with osteoarthritis and rheumatoid arthritis or other bony and joint pathologies, as hammering range of motion exercises in the population without good joint alignment is going to create more problems.
Modifiable elements include: tissue restrictions, tissue shortness, footwear type, and hypermobility of the midfoot and subtalar joints.
How to overcome?
When available, a smart manual therapist will go a long way in restoring good motion at the toe with some targeted work on the plantar surface of the foot itself as well as other areas that may potentially play a role in the abnormal forces on the feet, which can be as high up in the chain as the neck musculature. Physical therapists have the availability of joint mobilization and distraction techniques that have proven to be effective as well. The performance specialist has a number of tools available that can help restore function as well.
General self-treatment of the plantar surface of the foot with hands or a golf ball is typically a good first step. Next, some use of isometric contractions of the big toe flexors followed by a light and progressive stretch into extension can be helpful. Finally integrating the newfound range of motion into “spiked” ½ kneeling positions and driving the toe to the floor during other functional activities can help improve outcomes.