Today we should discuss treatment of sesamoid fractures from an orthotic standpoint. KevinRoot Medical has its Pre-set device for this called the P14 which emphasizes the medial arch for proximal transfer, 1st metatarsal punch for direct off loading, dancer’s padding, and an extrinsic rearfoot post for heel alignment and some medial column overload decrease. This can be a great starting point, and may be all you need to get the pain level consistently down to 0-2 which creates a healing environment.
But, let’s look again at our biomechanics we talked about last week. These biomechanics are:
- Plantarflexed first rays especially in Everted Forefoot Deformities
- Pes Cavus
- Bunion Formation with Sesamoid Malposition
- Rigid Foot Type (limited subtalar joint Range of Motion)
- Flail Hallux Purchase
- Weak Flexor Hallucis Longus/Brevis
- Hallux Limitus or Rigidus, functional (hopefully) or structural
- Medial column overload (from any source)
- Equinus force with increased metatarsal plantar pressures
- Weak Achilles tendon
Think about how each of these when recognized and corrected can help in relieving the stresses around the sesamoids.
- If you find a Plantarflexed first ray you can make sure the dancer’s padding is as thick as possible. This typically means 3 mm sulcus length for the dress shoes, and 4 mm tapered to the toes full length for the athletic orthotic devices. (Reverse Morton's to Sulcus, to Toes)
- Pes Cavus foot type just has more pressure on the metatarsal area which can be minimized by 1.5 mm overall arch fill.
- If a bunion exists, I tend to think distal to the plastic and have the patients get toe separators, YogaToes, and CorrectToes.
- The role of a rigid foot vs flexible foot in this discussion is that the more rigid the foot, the more it will respond to our corrections, and the opposite is true with a flexible foot (harder time stabilizing). I love foot mobilization work by a physical therapist between the time the orthotic devices are ordered and the time they are dispensed which is not always practical. An Rx for 8 visits of PT for foot mobilization work is super.
- When you perform your Functional Hallux LImitus exam, and you find the toe is very easy to lift up but the arch does not raise up, placing the patient on a 6 month progressive FHL and FHB strengthening regime is great to help develop these muscles for a strong pushoff
- Sesamoid pain can be part of a structural hallux limitus vs rigidus condition. So, at times it is hard to differentiate between the need to immobilize vs off load. You immobilize with Morton’s extensions, and you off load with Reverse Morton’s (dancer’s padding). Many of these patients have both types (Hallux Rigidus type and Sesamoid type) to trade off with. Again, I tend to use full length Morton’s in my athletic shoe design, and sulcus length in dress shoes.
- With overpronation and medial overload, you can get Functional Hallux Limitus, so you typically have to think about one of the P or Pronation Orthoses (previously discussed) as your base. Many times it is just normally balancing a forefoot varus that will give you that pronation control. I make sure that I retest the FHL at orthotic dispense to see if the devices eliminate or greatly reduce this functional hallux limitus.
- When you find the achilles weak and/or overflexible, you strengthen with heel raises and other exercises. My sesamoid patients typically need to do the heel raises or calf stretches with an accommodative for the sesamoid. The four book trick with a central dell to place the sesamoid in tends to work well when needed. Heel lifts for the orthotic devices would be a temporary control as they get stronger. I would place a heel lift on both sides for balance. 3 mm is pretty standard to start with.
- The use of heel lifts in tight achilles tendons is two fold. First we know that a tight achilles tendon produces equinus forces that intensify plantargrade forces across the metatarsals. So, it is important to reduce those with a temporary use of heel lifts, non-zero drop shoes, and achilles stretching. The second reason we use heel lifts for achilles tightness is based on how a tight achilles compensates. Excessive pronation and midfoot collapse are two compensations I want to allow until I can get the achilles normal length. Dr. Donald Green, in his brilliant article on Planal Dominance, explained how achilles tightness, a sagittal plane deformity, primarily caused sagittal plane damage. These children that come into your offices with a double heel off and early signs of a Rocker Bottom Flatfoot are examples of this destructive force.
Next week I will have another discussion on sesamoid fractures and the biomechanical flow of treatment over a 6 visit span.
