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I think what Kevin means is that there wont be an increased pronation if the lateral wedge is attached to a CFO and that the foot will be only in a more 'everted' position without encouraging unnecessary pronation., hence attating an increased medial opening of the KJ?? am I understanding it right?
If I was to construct an orthotic to act in one plane, I would be back at a lateral wedge.
I think with a triplanar device you are fighting what you are trying to accomplish.
Last edited by joseph_mozena@yahoo.com : 15th June 2011 at 06:09 AM.
Reason: formatting
I don't know what others do in regards to these valgus wedges. However, illustrated below is the shape of the adhesive felt temporary wedges I have been adding to the shoe insoles of my patients with medial knee osteoarthritis for the past 20 years. This design works great and is nearly always very well tolerated by the patient. Lesser or greater valgus wedging may be used depending on the comfort and the gait function of the patient.
I guess this is where my thinking is taking me that lesser or greater valgus wedging maybe used. Thanks Kevin.
Thanks is too small a word for what you are doing.
My wife thinks that what I do here on Podiatry Arena is a disease......just kidding......but poor Pam has to put up with a lot being married to me for 31 years. I couldn't do what I do without her continued support.
Hope all is well.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
My wife thinks that what I do here on Podiatry Arena is a disease......just kidding......but poor Pam has to put up with a lot being married to me for 31 years. I couldn't do what I do without her continued support.
Hope all is well.
Kevin,
1. I am not practicing at this time.
2. The more I study lateral foot wedging for medial OA, the less sense it is making.
3. I should be talking less.
4. I need to study more.
5. I think I will take another look at my self examination.
I think what Kevin means is that there wont be an increased pronation if the lateral wedge is attached to a CFO and that the foot will be only in a more 'everted' position without encouraging unnecessary pronation., hence attating an increased medial opening of the KJ?? am I understanding it right?
Let me explain more clearly so there is no misunderstanding. When we place a valgus wedge on the forefoot and rearfoot inside a patient's shoe to treat medial knee osteoarthritis (OA), the valgus wedge will simultaneously be causing multiple joint moments on the foot and lower extremity as follows:
With a very mild or early medial knee OA condition, I will normally put an 1/8" (i.e. 3 mm) thick rearfoot and forefoot valgus wedge on the patient's shoe insole or shoe sockliner to see how this works. This can be converted to a 1/8" korex wedge that is glued to the shoe insole if the all of the knee pain is relieved by this simple valgus wedge.
With moderate, more advanced, medial knee OA, the valgus correction will need to be greater to be able to reduce the medial knee compartment compression forces sufficiently to get sympomatic relief (by the way, the medial knee joint never "opens" with a valgus wedge-it just is compressed less than normal). Since the valgus wedge needs to be greater in degree, then so will the external STJ pronation and forefoot eversion moments be increased which may cause new symptoms in the foot or other gait pathology.
It is in these cases of moderate knee OA that I will nearly always insist on using a functional foot orthosis for the treatment of the medial knee OA. The functional foot orthosis, in addition to allowing me to vary the degree of rearfoot and forefoot valgus wedging to treat the pathological forces causing the symptoms of the medial knee OA, also allows me to add some support to the medial longitudinal arch of the foot to prevent subtalar or midtarsal joint symptoms that may arise from using larger degrees of rearfoot valgus and forefoot valgus wedging. The use of this type of orthosis, with a flat rearfoot post, lateral heel skive, everted balancing position, stiff lateral arch and valgus forefoot wedging, in my 20 years of clinical experience in treating such conditions with these specially-modified custom foot orthoses, is much better tolerated and more comfortable for the patient than simple valgus wedging alone.
When I lecture in Manchester, UK, in a few days at the Biomechanics Summer School, maybe I can cover these ideas more fully in one of the workshops I will be presenting during the conference, if one of you attending the conference will simply ask me to do so.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Mr Payne - in your study : Rana S. Hinman, Kelly Ann Bowles, Craig Payne, Kim L. Bennell: Effect of length on laterally-wedged insoles in knee osteoarthritis. Arthritis Care & Research, Volume 59 Issue 1, Pages 144 – 147, 2008
you used 5 degree lateral valgus wedges, and took readings from the asis and psis in the gait analysis, but didn't include any of the results in the article. was that because there were no changes at the hips with and without valgus wedges?
Sorry, that was a few yrs ago now and I just can't recall. I have emailed the others to check what was actually done.
__________________ Craig Payne
__________________________________________________ ___________________________________ Follow me on Twitter | Run Junkie God put me on this earth to accomplish a certain number of things - right now I am so far behind, I will never die.
Let me explain more clearly so there is no misunderstanding. When we place a valgus wedge on the forefoot and rearfoot inside a patient's shoe to treat medial knee osteoarthritis (OA), the valgus wedge will simultaneously be causing multiple joint moments on the foot and lower extremity as follows:
With a very mild or early medial knee OA condition, I will normally put an 1/8" (i.e. 3 mm) thick rearfoot and forefoot valgus wedge on the patient's shoe insole or shoe sockliner to see how this works. This can be converted to a 1/8" korex wedge that is glued to the shoe insole if the all of the knee pain is relieved by this simple valgus wedge.
With moderate, more advanced, medial knee OA, the valgus correction will need to be greater to be able to reduce the medial knee compartment compression forces sufficiently to get sympomatic relief (by the way, the medial knee joint never "opens" with a valgus wedge-it just is compressed less than normal). Since the valgus wedge needs to be greater in degree, then so will the external STJ pronation and forefoot eversion moments be increased which may cause new symptoms in the foot or other gait pathology.
It is in these cases of moderate knee OA that I will nearly always insist on using a functional foot orthosis for the treatment of the medial knee OA. The functional foot orthosis, in addition to allowing me to vary the degree of rearfoot and forefoot valgus wedging to treat the pathological forces causing the symptoms of the medial knee OA, also allows me to add some support to the medial longitudinal arch of the foot to prevent subtalar or midtarsal joint symptoms that may arise from using larger degrees of rearfoot valgus and forefoot valgus wedging. The use of this type of orthosis, with a flat rearfoot post, lateral heel skive, everted balancing position, stiff lateral arch and valgus forefoot wedging, in my 20 years of clinical experience in treating such conditions with these specially-modified custom foot orthoses, is much better tolerated and more comfortable for the patient than simple valgus wedging alone.
When I lecture in Manchester, UK, in a few days at the Biomechanics Summer School, maybe I can cover these ideas more fully in one of the workshops I will be presenting during the conference, if one of you attending the conference will simply ask me to do so.
Kevin,
Finally I understand what you are saying. Whew!
Sometimes storming comes before norming and out of chaos comes order.
Why the use of the lateral Kirby skive unless you are increasing the forefoot wedge over the subtalar joint wedge why not just increase both moments with a full length wedge.
Kevin also once the STJ is pronated isn't there less eversion available in the forefoot?
The eversion range of motion of the forefoot isn't as critical as moving the ground reaction force on the forefoot more laterally to increase the external knee abduction moment which will, in turn, decrease the compression force within the medial compartment of the knee.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
The eversion range of motion of the forefoot isn't as critical as moving the ground reaction force on the forefoot more laterally to increase the external knee abduction moment which will, in turn, decrease the compression force within the medial compartment of the knee.
The eversion range of motion of the forefoot isn't as critical as moving the ground reaction force on the forefoot more laterally to increase the external knee abduction moment which will, in turn, decrease the compression force within the medial compartment of the knee.
The knee joint axis is fighting the abduction moment?
The big picture questions:
Does this pain relief cause damage to the other joints affected by pronation thus causing more problems than it solves?
If this is damaging to other joints are not the various knee braces altering alignments doing the similar damage?
Are we tinkering with beautiful alignments that are not open to this type of intervention?
I can't answer these questions due to my practice interruptions.
Are the "medications" of orthotics so potent that they are like drugs and need to be prescribed only by physicians with a standard of care? Like drugs some are OTC and some Rx are the consequences so involved that only physicians should be prescribing orthotics or certain types of orthotics.
I consider Biomechanics harder than surgery should there be a separate board for this intervention noting that this field is only going to progress from FES to robotics? Is mixing orthopedics with medicine board mixing things to complex to do both?
Like the role of the pharmacist in medicine should the pedorthist handle the prescription with the same exactitude as the pharmacist?
Will the role of the pedorthist become like the pharmacist a doctorate?
The knee joint axis is fighting the abduction moment?
An axis is an imaginary line and cannot create moments. In genu varum, when you load from above and below the forces applied will tend to increase the varum deformity or that could be stated as an increased adduction moment on the tibia. When there is an adduction moment on the tibia it will adduct unless something prevents it. The force couple of downward force from the femur applied to the medial side of the tibial plateu and tension in the lateral ligaments will prevent the adduction of the tibia.
Quote:
Originally Posted by joseph_mozena@yahoo.com
The big picture questions:
Does this pain relief cause damage to the other joints affected by pronation thus causing more problems than it solves?
If this is damaging to other joints are not the various knee braces altering alignments doing the similar damage?
Are we tinkering with beautiful alignments that are not open to this type of intervention?
I've told this story before on the arena. I've got a pateint with sinus tarsi pain and medial knee pain. The first orthotic relieved his sinus tarsi pain (medial skive) and created knee pain. I shaved a little off the plantar medial rearfoot post, then a little more. His knee pain went away. A couple of months later he's back with sinus tarsi pain and knee does not hurt. I have him tape a coin to the underside of the medial edge of the orthtic to invert it a little more. Two weeks later he comes back and nothing hurts....... Remove the coin.....put it back....
Quote:
Originally Posted by joseph_mozena@yahoo.com
Are the "medications" of orthotics so potent that they are like drugs and need to be prescribed only by physicians with a standard of care? Like drugs some are OTC and some Rx are the consequences so involved that only physicians should be prescribing orthotics or certain types of orthotics.
I consider Biomechanics harder than surgery should there be a separate board for this intervention noting that this field is only going to progress from FES to robotics? Is mixing orthopedics with medicine board mixing things to complex to do both?
Like the role of the pharmacist in medicine should the pedorthist handle the prescription with the same exactitude as the pharmacist?
I'm pretty sure I know how orthotics work. However, there are a lot of other people who are quite sure how orthotics work. I disagree with their theories. So, how do we decide who's right so that they can be the only ones who an dispense custom orthotics.
I guess the analogy is to medications where the mechanism of action is not known. We, as the health professional have to evaluate our treatment and alter the treatment based on results.
Footwear modifications have been investigated as conservative interventions to decrease peak external knee adduction moment (EKAM) and pain associated with knee osteoarthritis (OA).
OBJECTIVE:
To evaluate the literature on the effect of different footwear and orthotics on the peak EKAM during walking and/or running.
METHODS:
A systematic search of databases resulted in 348 articles of which 33 studies were included.
RESULTS:
Seventeen studies included healthy individuals and 19 studies included subjects with medial knee OA. Quality assessment (modified Downs and Black quality index) showed an (average±SD) of 73.1±10.1%. The most commonly used orthotic was the lateral wedge, with three studies on the medial wedge. Lateral wedging was associated with decreased peak EKAM in healthy participants and participants with medial knee OA while there is evidence for increased peak EKAM with the use of medial wedges. Modern footwear (subjects' own shoe, "stability" and "mobility" shoes, clogs) were likely to increase the EKAM compared to barefoot walking in individuals with medial knee OA. Walking in innovative shoes ("variable stiffness") decreased the EKAM compared to control shoes. Similarly, shoes with higher heels, sneakers and dress shoes increased EKAM in healthy individuals compared to barefoot walking.
CONCLUSIONS:
Further development may be needed toward optimal footwear for patients with medial knee OA with the aim of obtaining similar knee moments to barefoot walking.
In-shoe plantar pressure measurements for patients with knee osteoarthritis: Reliability and effects of lateral heel wedges.
Leitch KM, Birmingham TB, Jones IC, Giffin JR, Jenkyn TR Gait Posture. 2011 Jul 6;
Quote:
Although plantar pressure measurement systems are being used increasingly during gait analyses to investigate foot orthotics, there is limited information describing test-retest reliability of such measurements. Objectives of this study were to (1) examine the test-retest reliability of lateral heel pressure (LHP) and centre of pressure (COP) during walking with and without lateral heel wedges, and (2) evaluate the effects of 4° and 8° lateral heel wedges on the magnitude of LHP, the pathway of the COP and the peak external knee adduction moment (KAM) in subjects with and without knee osteoarthritis (OA). Twenty-six subjects, 12 patients with knee OA and 14 healthy subjects, were evaluated during three lateral heel wedge conditions (control, 4° and 8°) with standardized footwear. Three-dimensional analyses of gait with optical motion capture, floor-mounted force plate and in-shoe plantar pressure were completed on two occasions. Intraclass correlation coefficients (ICC(2, 1)) for LHP were excellent (0.79-0.83) while ICCs for COP in the medial-lateral and anterior-posterior directions were more variable (0.66-0.86). Reliability was slightly diminished when using heel wedges. Standard errors of measurement suggested considerable day-to-day variability in an individual's measures. Lateral heel wedges significantly (p<0.001) increased LHP, shifted COP anteriorly and laterally, and decreased the KAM. No significant differences were observed between subjects with and without OA. Although the day-to-day variability appears too large to confidently evaluate changes in individual patients, and decreases in reliability with increases in wedge size indicate caution, these results suggest in-shoe measurement of LHP and COP are appropriate for use in studies evaluating biomechanical effects of foot orthoses for knee OA.
Lateral wedge insoles for medial knee osteoarthritis: Effects on lower limb frontal plane biomechanics.
Hinman RS, Bowles KA, Metcalf BB, Wrigley TV, Bennell KL Clin Biomech (Bristol, Avon). 2011 Aug 19;
Quote:
BACKGROUND: Lateral wedges reduce the peak knee adduction moment and are advocated for knee osteoarthritis. However some patients demonstrate adverse biomechanical effects with treatment. Clinical management is hampered by lack of knowledge about their mechanism of effect. We evaluated effects of lateral wedges on frontal plane biomechanics, in order to elucidate mechanisms of effect.
METHODS: Seventy three participants with knee osteoarthritis underwent gait analysis with and without 5° lateral wedges. Frontal plane parameters at the foot, knee and hip were evaluated, including peak knee adduction moment, knee adduction angular impulse, center of pressure displacement, ground reaction force, and knee-ground reaction force lever arm.
FINDINGS: Lateral wedges reduced peak knee adduction moment and knee adduction angular impulse (-5.8% and -6.3% respectively, both P<0.001). Although reductions in peak moment were correlated with more lateral center of pressure (r=0.25, P<0.05), less varus malalignment (r values 0.25-0.38, P<0.05), reduced knee-ground reaction force lever arm (r=0.69, P<0.01), less hip adduction (r=0.24, P<0.05) and a more vertical frontal plane ground reaction force vector (r=0.67, P<0.001), only reduction in knee-ground reaction force lever arm was significantly predictive in regression analyses (B=0.056, adjusted R(2)=0.461, P<0.001).
INTERPRETATION: Lateral wedges significantly reduce peak knee adduction moment and knee adduction angular impulse. It seems a reduced knee-ground reaction force lever arm with lateral wedges is the central mechanism explaining their load-reducing effects. In order to understand why some patients do not respond to treatment, future evaluation of patient characteristics that mediate wedge effects on this lever arm is required.
My observation based on having been assigned to adapt insoles until the muscles worked correctly.
Those adapting with the plantaris and/or planterflexing the hallux benefited from lateral wedges.
Those with Morton foot or chronic fore foot abduction did not benefit but did benefit with a flat lift under the distal first metatarsal. not a wedge which caused sliding rather than ground force contact. According to instruction from Rothbart height was determined by palpation of the tarsals resting square on the calcaneus. Height was adjusted as muscles strengthened and balanced.
My observation based on having been assigned to adapt insoles until the muscles worked correctly.
Those adapting with the plantaris and/or planterflexing the hallux benefited from lateral wedges.
Those with Morton foot or chronic fore foot abduction did not benefit but did benefit with a flat lift under the distal first metatarsal. not a wedge which caused sliding rather than ground force contact. According to instruction from Rothbart height was determined by palpation of the tarsals resting square on the calcaneus. Height was adjusted as muscles strengthened and balanced.
HansMassage:
You just lost all your credibility with me by mentioning the word "Rothbart" to describe anything to do with foot biomechanics. Just thought you should know that I am probably not the only one here that shares my thoughts in this regard.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Could someone please try and help me conceptualize how we get external adduction moments and internal abduction moments at the knee. I understand how using valgus wedging is able to shift the CoP laterally because I can visualize this concept in the frontal plane but how do adduction and abduction moments occur at the knee joint?
Could someone please try and help me conceptualize how we get external adduction moments and internal abduction moments at the knee. I understand how using valgus wedging is able to shift the CoP laterally because I can visualize this concept in the frontal plane but how do adduction and abduction moments occur at the knee joint?
Hi Danial,
It's helpful to think in terms of the force couples created and using free body diagrams. Take a leg with genu varum. Now just look at the foot and leg below the knee. The force from the body above (gravity acting on the body) will be lateral to the force from the ground on the bottom of the foot. (Draw this in the frontal plane.) These two forces will attempt to rotate the bottom of the tibia toward the midline. This is a knee adduction moment. I don't really like talking about internal and external, but would rather talk about the moment from one source versus the moment from another source. So the moment just described has to be countered to maintain equilibrium. We know it's in equilibrium because the knee will not be rotating when the person with genu varum is standing in static stance. So there has to be a moment from some other source, to maintain equilibrium. This can come from compression force on the medial side of the knee. Specifically, the force from the medial condyle of the femur applied to the top of the medial side of the tibia. The other force is tension in the lateral colateral lateral ligament of the knee. (The lateral collateral ligament applies an upward force on the tibia.) These two forces will create a force couple that will tend to rotate the bottom of the tibia away from the midline of the body. Both of these moments exist simultaneously. They are equal and opposite reactions.
The shifting of the center of pressure will change the lever arm of the force couple. And this is how the moment changes.
I hope this helps.
Eric
The Following User Says Thank You to efuller For This Useful Post:
Originally Posted by efuller View Post
The force from the body above (gravity acting on the body) will be lateral to the force from the ground on the bottom of the foot
Is the force from the body lateral due to the bodies CoM shifting laterally?
No the bodies center of mass can be in between the feet with a genu varum. However, the top of the tiba will be lateral to the bottom of the tibia because of the angle of the leg that is genu varum. What I did in the free body diagram analysis was to isolate the lower leg, remove the rest of the body and look at the forces applied to the lower leg. Two of those forces are: the doward weight of the body that the tibia is supporting, and the upward force from the ground applied to the foot. The center of mass of the body does not apply a force to the top of the tibia. The bottom of the femur applies a force to the top of the tibia.
Quote:
Originally Posted by Daniel Bagnall
Quote:
Quote:
Originally Posted by efuller View Post
These two forces will create a force couple that will tend to rotate the bottom of the tibia away from the midline of the body
So this would be defined as the internal abduction moment then?
One of the difficulties in using the terms internal and external is that it has to be internal or external to an arbitrarily defined system. When I defined my "system" as the lower leg, both of those forces are external to the system.
When results of knee adduction moment are reported, they are implying the "system" is the entire lower leg. So, the forces applied to the entire lower leg are the force from the body applied to the top of the femur and ground reaction force at the bottom of the foot. With genu varum these external forces will create an external adduction moment at the knee as they are external to the system. The tension in the lateral collateral ligaments and increased compression at the medial side of the knee are the internal forces that create the internal abduction moment. The internal abduction moment is equal and opposite to the external adduction moment.
This is why I don't really like the use of internal and external. You cannot calculate the magnitude of the knee moment unless you change your system to just the upper or lower leg as opposed to using the whole leg. Ideally, in mechanics, you describe the moment applied by one part to another part.
The difficulty that comes from the definition of the system was solved well in David Winter's articles and books. It's interesting to look at his diagrams and descriptions in relation to joint moments, because he usually works around this confusion very well.
Eric
The Following User Says Thank You to efuller For This Useful Post:
Could someone please try and help me conceptualize how we get external adduction moments and internal abduction moments at the knee. I understand how using valgus wedging is able to shift the CoP laterally because I can visualize this concept in the frontal plane but how do adduction and abduction moments occur at the knee joint?
Regards
Daniel
Daniel:
I like the concept of internal and external moments when I lecture and teach biomechanics. I find this type of terminology can be helpful in explaining how frontal plane moments are produced at the knee joint and especially can help in understanding the results from recent experiments where frontal plane knee moments are derived using inverse dynamics. In most biomechanics research using inverse dynamics, joint moments are reported as internal moments, not external moments.
If a valgus wedge under the foot shifts the center of pressure (CoP) laterally, then there will be an increase in external knee abduction moment. Now, if this valgus wedge doesn't increase the abduction motion of the knee, then, by the laws of rotational equilibrium, we know that must be some equal and opposite moment preventing the knee from abducting. Therefore, this equal and opposite moment, caused by the pulling of the ligaments around and in the knee and the change in joint compression forces due to the valgus wedge, is an internal knee adduction moment.
If a varus wedge under the foot shifts the center of pressure (CoP) medially, then there will be an increase in external knee adduction moment. Now, if this varus wedge doesn't increase the adduction motion of the knee, then, by the laws of rotational equilibrium, we know that must be some equal and opposite moment preventing the knee from adducting. Therefore, this equal and opposite moment, caused by the pulling of the ligaments around and in the knee and the change in joint compression forces due to the varus wedge, is an internal knee abduction moment.
The illustration below should help with this explanation. LCCF-lateral knee compartment compression force, MCCF-medial knee compartment compression force, LKTF-lateral knee tensile force
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Just to clarify, in the illustration I provided to you yesterday, the internal moments at the knee which I have included in my example are three separate internal forces:
1. Lateral knee compartment compression force which causes an internal knee adduction moment.
2. Medial knee compartment compression force which causes an internal knee abduction moment.
3. Lateral knee tensile force from lateral collateral ligament, biceps femoris muscle and iliotibial band which creates an internal knee abduction moment.
In my simplified example, I have left out other possible important contributors to internal knee moments such as the medial collateral ligament and sartorius, gracilis, semitendinosus, and semimembranosus muscles medially which all will create an internal knee adduction moment.
The external knee adduction moment in my example comes the ground reaction force vector (acting on the plantar foot) being located medial to the anterior-posterior axis of the knee.
Hope that further clarifies this illustration I provided yesterday that I use for one of my lectures on knee osteoarthritis and treatment of knee OA with foot orthoses.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
I have of late had a look at some of the literature on this subject. Im coming away with the feeling that lateral wedging does change knee moments which should change knee compressive forces. However clinical RCT's seem to be suggesting a lack of effectiveness ie in practice it doesnt work to reduce pain in knee OA.
I believe that Craig Payne has only recently published a study that came up with no improvement compared to the control group.
Anyone know of anything to change this opinion????
There was an interesting presentation from Peter Cavanagh at the ISB mtg in South Africa 2 yrs ago (I think it was that mtg!). He did a bit of a beat up on the biomechanists. For eg he talked about all the studies on how much pressure reduction occurred with a particular diabetic insole or shoe and the claims were made from that about the reduction in ulcer that would occur ... but the research was never taken through to clinical trials to see if that was actually the case or not.
The parallel here is the data on lateral wedging for medial knee OA.
1) Risk factor studies have shown a higher external adduction moment at the knee is a significant predictor of knee OA and a significant predictor of its progression
2) All (or almost all) lab based kinetic studies have shown a reduction in that moment with lateral wedging
3) Therefore this should help knee OA (see the parallels above with diabetic pressures and insoles/shoes eg)
When this gets taken through to the clinical trial, GENERALLY the uncontrolled trials show they work; the controlled studies with weaker methodology GENERALLY show they work. The one study we did that was well resourced, well controlled etc etc showed they did no better than the control group (though both groups improved equally)..... herein is the dilemma; what do we do with this information? There are several more well controlled RCT's on this underway....do we wait? Do we act on this info now?
__________________ Craig Payne
__________________________________________________ ___________________________________ Follow me on Twitter | Run Junkie God put me on this earth to accomplish a certain number of things - right now I am so far behind, I will never die.
The answer for me is easy on this one. I have been using valgus rearfoot and forefoot wedging for my patients with medial knee OA for 20+ years with good success for mild to moderate cases of medial knee OA. I will continue to do so regardless of what the research says. I pity the clinician that feels that they need to wait for "definitive research" to know what to do for their patients. Why wouldn't you use these wedges? They are cheap, have virtually no side effects, and if they do cause problems, then you take them out of the shoe...no harm done.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
The answer for me is easy on this one. I have been using valgus rearfoot and forefoot wedging for my patients with medial knee OA for 20+ years with good success for mild to moderate cases of medial knee OA. I will continue to do so regardless of what the research says. I pity the clinician that feels that they need to wait for "definitive research" to know what to do for their patients. Why wouldn't you use these wedges? They are cheap, have virtually no side effects, and if they do cause problems, then you take them out of the shoe...no harm done.
Wonderful thread..I would agree and add only this:
I have done many as well and the lateral wedge for us is our starting point to treatment of medial knee OA. The wedge progression is relative to the degree of medial offloading required for pain management and yes it is subjective. Once this fails to reasonably resolve the pain then the use of a medial compartment unloader is used as a next step. The whole idea is to keep a patient yet determined as too young for replacement sugery off the table for as long as you can. Sometimes they have to wait and they want pain relif and mobility. Sometimes the wedge was all they needed at all for many years. Each progression is different.
I not a evidence-slave! Its just that with this therapy the evidence is beginningg to suggest no clinical effect. This is not the same as no evidence!
I guess the question, Kevin, is what are you doing the researchers are not, or how are you measuring your outcome, compared to how they are measuring their's. Is it just a case that your patients wear their orthoses and those in the study dont?!
Re: Lateral foot wedging for medial knee OA
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