Exploring the Links Between Human Movement, Biomechanics & Gait
Month: June 2016
Can you guess why this person has left-sided plantar fasciitis?
This question probably seem somewhat rhetorical. Take a good look at these pedographs which provide us some excellent clues.
First of all, note how much pressure there is over the metatarsal heads. This is usually a clue that people are lacking ankle rocker and pressuring these heads as the leg cantilevers forward. This person definitely have a difficult time getting the first metatarsal head down to the ground.
Notice the overall size of the left foot compared to the right (right one is splayed or longer). This is due to keeping the foot and somewhat of a supinated posture to prevent excessive tension on the plantar fascia.
The increase splay of the right foot indicates more mid foot pronation and if you look carefully there is slightly more printing at the medial longitudinal arch. This is contributing to the clawing of the second third and fourth toes on the right. Stand up, overpronate your right foot and notice how your center of gravity (and me) move medially.The toes will often clench in an attempt to create stability.
The patient’s pain is mostly at the medial and lateral calcaneal facets, and within the substance of the quadratus plantae with weakness of that muscle and the extensor digitorum longus. She has 5° ankle dorsiflexion left and 10 degrees on the right and hip extension which is similar.
The lack of ankle rocker and hip extension or causing her to pronate through her midfoot, Tensioning are plantar fascia at the insertion. The problem is worse on the left and therefore that is where the symptoms are.
Pedographs can be useful tool in the diagnostic process and provide clues as to biomechanical faults in the gait cycle.
An interesting, free, full text article we ran across entitled: “THE EFFECT OF WALKING IN FOOTWEAR WITH VARYING HEELSOLE DIFFERENTIALS ON SHANK & FOOT SEGMENT KINEMATICS”
Not exactly a page turner but some important pearls to glean here.
CONCLUSION: During 0-50% gait cycle stance phase shank kinematics do not change with changes in Heel Sole Differential. Actual foot angles do change, increasing with increasing Heel Sole Differential of footwear and by the angle of pitch of the footwear.
In other words, the kinematics (read: flex and physical characteristics) of the shank (the platform that the shoe is built on) do not change with increased ramp delta (ie: “drop”, from heel to toe), but foot kinematics (ie: how the foot moves) DOES change.
Have you ever heard of Klippel-Trenaunay Syndrome? I hadn’t either, until I had a patient come in with low back pain and a gait issue and said she had it.
Evidently, in 1900, noted French physicians Klippel and Trenaunay first described a syndrome in 2 patients presenting with a port-wine stain and varicosities of an extremity associated with hypertrophy of the affected limb’s bony and soft tissue. Klippel-Trenaunay-Weber syndrome (KTWS) is characterized by a triad of port-wine stain, varicose veins, and bony and soft tissue hypertrophy involving an extremity (1).
Most cases KTWS are sporadic, although a few cases in the literature report an autosomal dominant pattern of inheritance (2). There is no racial predilection, even distribution between males and females and presents at birth or during early childhood (3). It generally affects a single extremity, although cases of multiple affected limbs have been reported. The leg is the most common site followed by the arms, the trunk, and rarely the head and the neck(4).
This patient had a history of low back pain with a recent epidural steroid injection. Exam highlights included a R sided leg length discrepancy approximately 5mm (tibial and femoral). Pelvic tilt to the right (for LLD) with anterior rotation of that side of the pelvis, posterior on the opposite side (counter clockwise pelvic distortion pattern). Lumbar flexion off 60/90 with all motion occurring in the lumbar spine (ie: no hip hinge), extension 20/30, lateral bending 30/45 BL with pain ipsilateral. Decreased low back endurance of <50 seconds in extension.
Right lower extremity was smaller (appeared hypoplastic) than left and had multiple discolorations in the skin (see pictures). L sided Q angle > R (12 vs 8 degrees). Less internal rotation of the right lower extremity compared to left, but with normal limits. Gait revealed a shift and hike to the right during stance phase with an increased arm swing on the right. Foot intrinsics were weak (lumbricals, EDL, FDB, dorsal intrerossei)
She walked in a pair of Chaco sandals with allowed much greater calcaneal eversion bilaterally R > L.
MRI revealed paraspinal marbling at the lower part of the lumbar spine, improving as you move rostrally. Small disc herniations at L3/4, 4/5, 5/S1, which did not effect the exiting nerve roots. Degenerative changes in the lumbar facet joints. There was no radiographic evidence of instability.
Impression: It seems that she did not have enough intrinsic for the strength to stop calcaneal eversion in her Chaco’s and therefore this was causing increased foot pronation. This, combined with her leg length discrepancy, was contributing to increasing the lordosis in her lumbar spine, causing facet joint irritation. This was compounded by weakness and lack of endurance of the lumbar paraspinal musculature. The effects of the Klippel-Trenaunay Syndrome are evident with the IPO plasticity of the right lower extremity and accompanying musculoskeletal abnormalities.
What did we do?
Gave her endurance exercises for the lumbar spine.
Gave her propriosensorv exercises for the lumbar spine
Recommended she continue with the 5 mm sole lift.
Advised getting rid of the Chaco sandals as they allow too much calcaneal eversion and sticking to a shoe that has a stronger/larger heel counter.
acupuncture to improve circulation and proprioception as well as muscular function
we will monitor weekly for the next 4 to 6 weeks.
All in all, and interesting use with a little twist (not a torsion, of course!) : )
Riding the inside edge of the sandal. Mystery hunting with Dr. Allen.
You can see it in the photo above, the heel is a third of the way off the sandal. (there are 2 photos provided today, find the arrow and tab to see both)
You either have it or have seen it. It is frustrating as hell if you have it. Your heel rides on only half of your flip flop or summer sandals. You do not notice it in shoes, only in sandals, typically ones without a back or back strap. This is because the heel has no controlling factors to keep it confined on the rear of the sandal sole. But there is a reason this happens to some, but not everyone. It is best you read on, this isn’t as simple as it might seem.
These clients have restricted ankle rocker (dorsiflexion), restricted hip extension and/or adductor twist (if your reference is the direction the heel is moving towards). I could even make a biomechanical case that a hallux limitus could result in the same scenario. So what happens is that as the heel lifts and adducts it does not rise directly vertically off the sandal, it spins off medially from the “adductor twist” event. This event is largely from a torque effect on the limb from the impaired sagittal mechanics as described above, manifesting at the moment of premature heel rise resulting in an slightly externally rotating limb (adducting heel). The sandal eventually departs the ground after the heel has risen, but the sandal will rise posturing slightly more laterally ( you can clearly see this on the swing leg foot in the air, the sandal remains laterally postured). Thus, on the very next step, the sandal is not entirely reoriented with its rear foot under the heel, and the event repeats itself. The sandal is slightly more lateral at the rear foot, but to the wearer, we believe it is our heel that is more medial because that is the way it appears on the rear of the sandal or flip flop. Optical illusion, kind of… . . a resultant biomechanical illusion is more like it.
You will also see this one all over the map during the winter months in teenagers who swear by their Uggs and other similar footwear, as you can see in the 2nd photo above. This is not an Ugg or flip flop problem though, this is often a biomechanical foot challenge that is not met by a supportive heel counter and may be a product of excessive rear foot eversion as well. This does not translate to a “stable” enough shoe or boot, that is not what this is about. This is about a rearfoot that moves to its biomechanical happy place as a result of poor or unclean limb and foot biomechanics and because the foot wear does not have a firm stable and controlling heel counter. The heel counter has several functions, it grabs the heel during heel rise so that the shoe goes with the foot, it give the everting rearfoot/heel something to press against, and as we have suggested today, it helps to keep the rearfoot centered over the shoe platform. To be clear however, the necessary overuse and gripping of the long toe flexors to keep flip flops and backless sandals on our feet during the late stance and swing phases of gait, clearly magnifies these biomechanical aberrations that bring on the “half heel on, half heel off” syndrome.
There you have it. Another solution to a mystery in life that plagues millions of folks.
Dr. Shawn Allen, mystery hunter, and one of the gait guys.
Treadmills, motorized or nonmotorized can have some pitfalls. Here are seven of our biggest concerns.
More on non motorized treads from Mike Reinold which came to my attention via Scott Tesoro (thanks!).
1. Watch out for how much ankle dorsiflexion(and great toe extension) your client has to be able to take advantage of the “curve”
2. The treadmill, whether motorized or not, is constantly moving, opposite the direction of travel. With the foot on the ground, this provides a constant rate of change of length of the gastroc/soleus (ie, it is putting it through a slow stretch); so, once the muscle is activated, it contracts for a longer period of time because of the treadmill putting a slow stretch on the gastroc and soleus.
3. The moving deck also has a tendency to put the ankle in dorsiflexion ( see point number one) initiating a stretch reflex in the tricep surae (gastroc/soleus) facilitating toe off through here and pushing you through the gait cycle, rather than pulling you through (with your hip extensors).
4. Likewise, the treadmill pulls the hip into extension and places a pull on the anterior hip musculature, especially the hip flexors including the rectus femoris, iliopsoas and iliacus. This causes a slow stretch of the muscle, activating the muscle spindles (Ia afferents) and causing a mm contraction (ie the stretch reflex). This acts to inhibit the posterior compartment of hip extensors through reciprocal inhibition, especially the glute max, making it difficult to fire them.
5. Because the deck is moving, the knee is brought into extension, with stretch of the hamstrings, the quads become reciprocally inhibited.
6. the moving deck forces you to flex the thigh forward for the next footstrike (ie footstance), firing the RF, IP and Iliacus, and reciprocally inhibit the g max
7. If your core isn’t engaged, the pull of the rectus femoris and iliopsoas/iliacus pulls the ilia and pelvis into extension (ie increases the lordosis) and you reciprocally inhibit the erectors and increase reliance on the multifidus and rotatores, which have short lever arms and are supposed to be more proprioceptive in function.
We are not saying they are bad and in fact, we tend to like self-propelled models more than motorized ones and agree with many of the points made. We are just saying that treadmills are not the same as walking on a flat surface and approximate but do not simulate actual gait.