Exploring the Links Between Human Movement, Biomechanics & Gait
Do you treat runners? Do you treat folks with knee pain? Patellar tracking issues? Do you treat the quadriceps? Do you realize that the vastus lateralis, in closed chain, is actually an INTERNAL rotator of the thigh (not a typo), and many folks have a loss of internal rotation of the hip? Do you give them “IT band stretches” to perform?
In this short video, Dr Ivo demonstrates some needling techniques for the quads and offers some (entertaining) clinical commentary on the IT band. A definite view for those of you who have needling in their clinical tool box.
We had a great PODcast in the studio last Friday, talking about tendon vascularity and compression vs tension therapies for tendinopathies.
Here is a great FULL TEXT article on tendon vascularity that can serve as a catalyst for designing your treatment programs
“Conclusions Neovascularization is critical to tissue repair and wound healing. Therefore, strategies to enhance vascularization to promote regeneration are considered promising treatment modalities, i.e., the use of platelet rich plasma (PRP) to restore functional bone (Zhang et al., 2013) or skin (Kakudo et al., 2011). However, in acute or chronic tendon injuries hypervascularity often does not pave the way to functional recovery of the tissue. Therefore, to overcome the limited intrinsic regeneration capacity of tendon and to achieve scarless healing will most likely require a balanced manipulation of the angiogenic response in tendon tissue. For a variety of treatment methods, such as the use of PRP, the availability of clinical data is limited, due to heterogeneity in application (Khan and Bedi, 2015). In order to develop rational strategies to achieve a well-balanced angiogenic response following tendon injury, we need a thorough understanding of the molecular and cellular networks driving tendon vascularization and regeneration—a challenge for years to come.”
Taking advantage of the stretch reflex and reciprocal inhibition; or the “reverse stretch”
Reciprocal inhibition is a topic we have spoken about before on the blog (see here). The diagram above sums it up nicely. Note the direct connection from the spindle to the alpha motor neuron, which is via a Ia afferent fiber. When the spindle is stretched, and the pathway is intact, the uscle will contract. What kind of stimulus affects the spindle? A simple “stretch” is all it takes. Remember spindles respond to changes in length. So what happens when you do a nice, slow stretch? You activate the spindle, which activates the alpha motor neuron. If you stretch long enough, you may fatigue the reflex. So why do we give folks long, slow stretches to perform? Certainly not to “relax” the muscle!
How can we “use” this reflex? How about to activate a weak or lengthened muscle? Good call.
Did you notice the other neuron in the picture? There is an axon collateral coming off the Ia afferent that goes to an inhibitory interneuron, which, in turn, inhibits the antagonist of what you just stretched or activated. So if you acitvate one muscle, you inhibit its antagonist, provided there are not too many other things acting on that inhibitory interneuron that may be inhibiting its activity. Yes, you can inhibit something that inhibits, which means you would essentially be exciting it. This is probably one of the many mechanisms that explain spasticity/hypertonicity
How can we use this? How about to inhibit a hypertonic muscle?
Lets take a common example: You have hypertonic hip flexors. You are reciprocally inhibiting your glute max. You stretch the hypertonic hip flexors, they become more hypertonic (but it feels so good, doesn’t it?) and subsequently inhibit the glute max more. Hmm. Not the clinical result you were hoping for?
How about this: you apply slow stretch to the glutes (ie “reverse stretch”) and apply pressure to the perimeter, both of which activate the spindle and make the glutes contract more. This causes the reciprocal inhibition of the hip flexors. Cool, eh? Now lightly contract the glutes while you are applying a slow stretch to them; even MORE slow stretch; even MORE activation. Double cool, eh?
Try this on yourself. Now go try it on your clients and patients. Teach others. Spread the word.
Reciprocal Inhibition anyone? Thanks to The Manual Therapist (Erson Religioso) for this great post.
What they are doing here is taking advantage of what Sherrington know many years ago. Activating a muscle (agonist for a movement) will inhibit the muscle with the opposite action (antagonist for a movement), through a disynaptic, post synaptic pathway. It is a great way to gain additional movement and remove or reduce muscular inhibition. Try it!
Yes, we know it was surface emg; yes we know they are not necessarily testing functional movements. The EMG does not lie and offers objective data. Note that the one graph is labelled wrong and is the G max, not medius.
Kristen Boren, DPT,1 Cara Conrey, DPT,1 Jennifer Le Coguic, DPT,1 Lindsey Paprocki, DPT,1 Michael Voight, PT, DHSc, SCS, OCS, ATC, CSCS,1 and T. Kevin Robinson, PT, DSc, OCS1 ELECTROMYOGRAPHIC ANALYSIS OF GLUTEUS MEDIUS AND GLUTEUS MAXIMUS DURING REHABILITATION EXERCISES Int J Sports Phys Ther. 2011 Sep; 6(3): 206–223.
For clinicians and some die hard foot geeks, we often like to keep things objective. What could be more objective than an angular measurement? A few important measurements when examining or radiographing feet can give us information about clinical decision making (not that we suggest radiographs for mensuration purposes unless you are a surgeon, but when they are already available, why not put them to good use ?). When things fall outside the accepted range, or appear to be heading that way, these numbers can help guide us when to intervene.
Hallux valgus refers to the big toe headed west (or east, depending on the foot and your GPS). In other words, the proximal and distal phalanyx of the great toe (hallux) have an angle with the 1st metatarsal shaft of typically > 15 degrees. This angle, called the Hallux Valgus Angle (HVA above) is used to judge severity, often for surgical intervention purposes but can guide conservative management as well.
Metatarsus Primus Varus (literally, varus deformity of the 1st metatarsal) often accompanies Hallux Valgus. It describes medial deviation of the 1st metatarsal shaft, greater than 9 degrees. This angle is called the intermetatarsal angle and is measured by the angle formed by lines drawn parallel along the long axis of the 1st and 2nd metatarsal shafts.
One other measurement is the Distal Metatarsal Articular Angle, which measures the angle between the metatarsal shaft and the base of the distal articular cap (ie, where the cartilage is) of the 1st metatarsal. This typically should be less than 10 degrees, preferably less than 6 degrees. Remember, these are static angles, things can change with movement, engagement, weight bearing strategies and shoes. What you see statically does not always predict dynamic angles and joint relationship.s
Are you doing surgery? Perhaps, as a last resort. Hallux valgus and metatarsus primus varus can be treated conservatively.
How do you do that?
The answer is both simple and complex.
The simple answer is: anchor the head of the 1st ray and normalize foot function. This could be accomplished by:
EHB exercises to descend the head of the 1st metatarsal
exercise the peroneus longus, to assist in descending the head of the 1st metatarsal
short flexor exercises, such as toe waving, to raise the heads of the lesser metatarsals relative to the 1st
work the long extensors, particularly of the lesser metatarsals to create balance between the flexors and extensors
consider using a product like “Correct Toes” to normalize the pull of the muscles and physically move the proximal and distal phalanyx of the hallux
wear shoes with wide toe boxes, to allow the foot to physically splay
consider using an orthotic with a 1st ray cut out, to help descend the head of the 1st metatarsal
This is by no means an exhaustive list and you probably have some ideas of your own.
The complex answer is that in the above example, we have only included conservative interventions for the foot and have not moved further up the kinetic (or neurological chain). Could improving ankle rocker help create more normal mechanics? Would you accomplish this by working the anterior leg muscles, the hip extensors, or both? Could a weak abdominal external oblique be contributing? How about a faulty activation pattern of the gluteus medius? Could a congenital defect or genetic be playing a role? We have not asked “What caused this to occur in the 1st place?”
Examine your patients and clients. Understand the biomechanics of what is happening. Design a rehab program based on your findings. Try new ideas and therapies. it is only through our failures that we can truly learn.
This simple screening test becomes a form of exercise.
Last week we explored the “Lean” test to see how your QL and gluteus medius were paired. Today we look at a simple CNS screen for your “central pattern generators” or “CPG’s”. If you do not pass, then the exercise becomes the rehab exercise. If you (or your client) does not have good coordination between the upper and lower extremity, then they will not be that efficient, physiologically or metabolically.
The “cross crawl” or “step test” looks at upper and lower extremity coordination, rather than muscular strength. If performed for a few minutes, it becomes a test that can look at endurance as well.
It is based on the “crossed extensor” response, we looked at last week. That is, when one lower limb flexes, the other extends; the contralateral upper limb also flexes and the ipsilateral upper limb extends. It mimics the way things should move when walking or running.
Stand (or have your client stand) in a place where you will not run into anything.
Begin marching in place.
Observe for a few seconds. When you (or your client) are flexing the right thigh, the left arm should flex as well; then the left thigh and right arm. Are your (their) arms moving? Are they coordinated with the lower extremity?
What happens after a few minutes? Is motion good at 1st and then breaks down?
Now speed up. What happens? Is the movement smooth and coordinated? Choppy? Discoordinated?
now slow back down and try it with your (their) eyes closed
If movement is smooth and coordinated, you (they) pass
If movement is choppy or discoordinated, there can be many causes, from simple (muscle not firing, injury) to complex (physical or physiological lesion in the CNS).
If movement is not smooth and coordinated, try doing the exercise for a few minutes a day. You can even start sitting down, if you (they) cannot perform it standing. If it improves, great; you were able to help “reprogram” the system. If not, then you (they) should seek out a qualified individual for some assistance and to get to the root of the problem.
The Gait Guys. Giving you information you can use and taking you a little deeper down the rabbit hole with each post.