A case of severe mechanical gait challenges.
This is a unique case. This is a complicated case, there is so much going on. If your eye is getting good at this gait analysis stuff you will know that just from the first pass this gait is very troubled.
This young middle distance runner who came to see us with complaints of chronic anterior and posterior shin splints. This is unusual because usually only one of the lower limb compartments are strained, either the anterior (tibialis anterior mostly) or the posterior compartment (tibialis posterior mostly). Admittedly this is not a fast runner but they love to run none the less, so you do what you can to help.
Please watch this video again and note the following:
- crossing over of the knees at the midline (this indicates a scissored gait / circumductory motion of the limbs)
- slightly wider based gait compared to knee postioning but neutral compared to hip spacing
- client starts heavily on the outer edge of the feet and moves medially
- client over strides (step length is increased) which is particularly evident when they are walking towards the camera
- early bunion formation and troubles engaging the big toe during stance phase
- the knees / patella also appear medially positioned in an environment of a neutral foot progression angle
- if you look carefully you can see that they rear foot immediately moves into a valgus posturing (this is rearfoot pronation) and they are also pronating into the forefoot heavily. Interestingly they have decent arch height.
Wow ! So much going on ! This is a gait from hell in some respects. So, what is driving so much of the terrible gait mechanics ? The answer is a congenital loss of ankle rocker (dorsiflexion) bilaterally. This client can barely squat because the ankles just do not dorsiflex. There was clear osseous lock at barely 90 degrees.
Lets break each one down.
- Crossing over of the knees at the midline (this indicates a scissored gait / circumductory motion of the limbs). * This is occuring due to some genu valgum of the knees (slightly “knock-knee”). When the knees are valgum they are at risk for brushing together during gait. The client has no choice but to circumduct the limbs to avoid this behavior. Unfortunately they cannot abduct the thighs far enough during many of the gait cycles and so a “Scissored” appearance occurs where the thighs brush and cross over in appearance.
- Slightly wider based gait compared to knee positioning but neutral compared to hip spacing. * This is closely related to our answer in #1. Valgus knees will widen the foot spacing side to side because the feet are not under the knee joints. Then couple this with the necessity to circumduct to avoid knees from contacting and the foot posturing is that of an even wider based gait. This can also occur from many hip problems. However as in this case with a congenital loss of ankle rocker, the client uses more foot pronation to progress the tibia over the talus (allowing the tibia to get past 90degrees) and allow them to move forward. This added pronation does magnify and likely progress the knee valgum but there are few other options for this client. This is often a destructive vicious cycle with few good outcomes decades down the road.
- Client starts heavily on the outer edge of the feet and moves medially. *This may be to avoid the immediate rear foot pronation that is seen here.
- Client over strides (step length is increased) which is particularly evident when they are walking towards the camera. * This may be a conscious attempt to lengthen the shortened stride that occurs because of the limited ankle dorsiflexion ranges. It appears at many moments however to be a result of the extra effort to circumduct the legs sufficiently. A longer stride does play into #3 above, a larger stride usually leads to a heavier lateral heel strike but it also means that the rearfoot pronation will be more aggressive, this is a negative resultant outcome.
- Early bunion formation and troubles engaging the big toe during stance phase. *We are not surprised here. Whenever pronation is excessive the first metatarsal (medial foot tripod) is unstable and this changes the mechanics of the hallux muscles to pull towards the 5th metatarsal anchor generating the bunion. Look at the origin and insertion of the adductor hallucis muscle particularly the transverse head, if the 1st MET is anchored the 5th MET is pulled to the 1st and the transverse arch is formed. However, if the 1st MET is unstable and the 5th is the only anchor, the adductor hallucis will pull the toe laterally and form a bunion and hallux valgus and compromise the transverse arch. (particularly look at the left big toe at the :09 to :11 second mark, the big toe and first MET are clearly not anchored to the ground).
- The knees / patella also appear medially positioned in an environment of a neutral foot progression angle. * Answers for #1-#5 clearly will medial patellar deviation and drive patellar tracking problems.
- If you look carefully you can see that they rear foot immediately moves into a valgus posturing (this is rearfoot pronation) and they are also pronating into the forefoot heavily. Interestingly they have decent arch height, but remember, that does not mean that pronation is not occurring. * This is a result of the loss of ankle rocker mechanics. If they start pronation early at the rear foot it will drive more pronation. When pronation is driven excessively the arch can drop, and with more arch height drop the tibial will pitch forward past the magical 90 degree mark and allow forward motion to occur.
So, how can they run with all this going on ? Well, the answer is quite simple. They avoid most of these issues as best they can. How you ask ? Forefoot strike; they run avoiding heel strike and midfoot strike. By staying on the forefoot all of these rear and midfoot mechanical limitations as well as ankle rocker loss can be avoided by remaining on the forefoot. This makes distance running difficult but anything below the two mile mark is tolerable and the 100-800 distances are probably best suited for their feet. Incidentally they enjoy the 400 the best, no wonder. Also, moving at increased speed will necessitate a forward lean, and a forward lean makes the tibia progression over the talus easier taking out some of the ankle rocker limitations.
This is a foot type, with complications, that is really beyond much of what anyone can do conservatively. We would even argue that surgery is not an option, just a change in activity choice. This is simply a client that should not run beyond distances where they can stay on the forefoot. The foot, ankle and lower limb mechanics just suffer far to much from having to compensate (as discussed in #1-7) to enable pain and problem free running with anything other than forefoot loading. This means that walking is going to be difficult and problematic, as you can see from this video above.
Our only solution in this case ? ……… utilizing a rocker based footwear. Easy Spirit Get UP and Go (link) was our recommendation and it worked very well for this client for walking. Here is a link to this shoe and pictures of the huge forefoot rocker that helps (somewhat) to dampen the mid-forefoot rocker issues but there is not much that can be done for the rear foot rocker issues as discussed. If you use an orthotic to block the rearfoot valgus motion and rearfoot pronation you will pass more challenges to the midfoot-arch and forefoot. Sadly.
This was a very tough case. Getting every aspect of the case in your head during an evaluation is sometimes a challenge. Sometimes you need to see them a 2nd or 3rd time to digest it all. But be patient with yourself, it takes time to get decent at this stuff. This is a perfect case for “getting a feeling and flow” of the persons gait, at their speed. A case evaluation like this on a treadmill or via video analysis can make things tougher because the treadmill can change the dynamics (did you read our Treadmill article in last months Triathlete magazine ? It was linked on the blog 2 weeks ago) and make the client move at its speed and not their speed inhibiting and promoting different mechanics. There are times for a treadmill and times to avoid them. This is an art, in time you will know when to use and when not to use.
Happy Monday Gait Gang………. welcome to The Gaits of Hell !
Shawn and Ivo ……….two gnarly lookin dudes with pitchforks and a toothy grin.