This is part 10 of a series that should be read in order.
Key Points:
- What is negative about pronating a patient pass their MPP?
- What are the standard Rx modifications to help patients that supinate at heel contact?
- How does S1, S2, and S3 Differ and how to decide which one based on the degree of correction needed?
Now, there are 3 versions (that I know of) of more lateral support besides a B1 orthosis with forefoot valgus/plantarflexed first ray support and BS in a shape based orthosis with lower medial arch and Denton modification. And, the caveat is that you must know where MPP is and avoid it as you can not jam up the subtalar joint laterally. Since my general rule for all patients is to make them more stable, avoiding MPP is a must. These are orthoses where you are actively changing the basic Rx.
These 3 orthoses for supination control are S1, S2, and S3 in our classification. S1 is your standard device (B) with all the anti-supination bells and whistles. These include: higher lateral heel cup (typically 18 mm or more), lateral phalange, zero motion rearfoot post, Denton modification, narrower orthosis than normal, and lower medial arch than normal. You have to relate this, and the lab has to relate this, to what you do in your Gold Standard (My-Go-To from Dr. Stefan Feldman) B1 or B2 device. S2 is S1 plus ⅛ inch valgus wedge to sulcus, Feehery cuboid support, ⅛ inch support sub 4 and 5 metatarsal heads, and setting the cast correction not at vertical, but at 2 degrees everted. So now you are placing modifications that could evert the foot to the ground with the goal typically of just stopping the inversion roll of the heel during the contact phase. S3 is S2 with a 3 mm lateral heel Kirby skive and a 3/16 inch total valgus wedge to the sulcus. With S3, I typically have to raise the lateral heel cup to 25 mm or more and even add a ¼ inch valgus wedge to the midsole. If I am valgus wedging the outsole, I use a ⅛ inch valgus wedge since outsole wedges are more powerful. The classification of S1, S2, and S3 do not correlate well to static measurements (most of the time), since laterally unstable supinators are so much worse dynamically. However, in my estimate, you can think about them as:
BS 1 degree change (mild correction)
S1 2-3 degree change (moderate correction)
S2 3-4 degree change (moderate+ correction)
S3 4-6 degree change (severe correction)
Let’s look at one example needing S orthoses.
Example 1
RCSP 3 Inverted
NCSP 4 Inverted
MPP 7 Everted
FF/RF 8 degrees Valgus
The difference here between RCSP and MPP was 10 degrees of subtalar joint eversion. Therefore, if we need a valgus wedge, it will be hard to get to the maximally pronated position. The 3 degree Inverted heel of RCSP must be compensation for Forefoot Valgus (here I use forefoot valgus and plantar flexed first ray interchangeably). After I measured the RCSP, I placed my hand under the 4th and 5th metatarsals easily everting the heel past vertical (I was modifying the Coleman Block Test, and mimicking what Root Balancing of the Forefoot Valgus would do). I then casted and ordered a B1 device with full forefoot valgus support, and the OCSP was 1 degree everted, and all contact phase supination had been eliminated. Easy?
Yes, for walking I had a stable orthosis. However, this patient was a terrible supinator with running and developed chronic related Ilio-Tibial Band Syndrome due to the varus stress all the way up the leg. I made the choice of eliminating contact phase supination over anything else. It is such a devastating motion. I eventually needed a separate orthosis for his running with S2 correction.
Review of all the Orthotic Types Being Presented
Corrective Orthotic Devices
↓
- Balancing (B): (B1 and B2)
- Pronators (P): BP, P1, P2, P3, P4, P5, and P6
- Supinators (S): BS, S1, S2, S3
- M/L Instability (M): BML, ML1, ML2, ML3, ML4, ML5, and ML6
- Shock Absorption (C): BC, C1/C2, C3/C4/C5, C6, and C7
- Sagittal Plane (H): BH, H1, H2, and H3
