Welcome to the Podiatry Arena forums, for communication between foot health professionals about podiatry and related topics.
You are currently viewing our podiatry forum as a guest which gives you limited access to view all podiatry discussions and access our other features. By joining our free global community of Podiatrists and other interested foot health care professionals you will have access to post podiatry topics (answer and ask questions), communicate privately with other members (PM), upload content, view attachments, receive a weekly email update of new discussions, earn CPD points and access many other special features. Registered users do not get displayed the advertisments in posted messages. Registration is fast, simple and absolutely free so please, join our global Podiatry community today!
If you have any problems with the registration process or your account login, please contact contact us.
Recently presented at June ACSM mtg in Denver: A Randomized Clinical Trial Evaluating the Effectiveness of Prefabricated and Custom Foot Orthoses Regimens Using Functional Outcome Measures
Quote:
Foot orthoses are common interventions that are often intended to increase performance, reduce deformity, and improve pathology. Although prefabricated foot orthoses (PFO) are less expensive and more readily available than custom foot orthoses (CFO), the latter are more customizable. Which intervention provides superior functional outcomes is unclear.
Purpose: To determine the effectiveness of prefabricated and custom foot orthoses regimens as they exist within current clinical practice, using different outcome measures including functional and pain scales, and a performance test.
Methods: Subjects with lower extremity overuse injuries were randomized to receive either PFO’s (n = 9) or CFO’s (n = 10), in combination with out patient physical therapy interventions as required. Outcome measures included: 1) the Lower Extremity Functional Scale (LEFS); 2) a Visual Analogue Pain Scale (VAPS); 3) the Patient Specific Functional Scale (PSFS), and; 4) a rucksack treadmill walk test. Analysis of covariance was used to compare the week six scores on the LEFS, VAPS, and PSFS while adjusting for group differences in baseline scores. Rucksack walking results were analyzed using Chi square and McNemar’s tests for correlated samples.
Results: Subjects who were prescribed the PFO’s performed significantly better on three of four outcome measures. Adjusted week six scores were superior on the LEFS (PFO 73.1 ± 4.8 vs CFO 66.9 ± 4.9, p<0.05), the VAPS (PFO 6.2 ± 9.4 vs CFO 18.3 ± 9.5, p<0.05), and a significantly higher proportion of PFO subjects improved to complete the rucksack walk test (p<0.05). Adjusted week six PSFS scores were not significantly different between the two groups (PFO 24.3 ± 5.7 vs CFO 20.0 ± 5.7; p=0.14).
Conclusion: Prefabricated foot orthoses, in conjunction with outpatient physical therapy interventions, were associated with superior functional outcomes and less pain six-weeks after prescription. These results suggest that less expensive prefabricated orthoses can be as effective as custom orthoses.
OK, new rule: Lets keep discussion in this thread to the above research and leave all the traditional prefab vs custom made stuff to the other threads. Hopefully Andy will be along soon with links to those threads.
Last edited by Admin : 22nd September 2006 at 09:04 PM.
Reason: typo
What a woefully designed study. I don'tknow how these studies get off the ground in the first place. Surely somebody pointed out the flaws in the methodology? Moreover, who then decides this is worthy of presentation? Too much of this at the moment, at best it is misleading.
__________________ Science is the antidote to the poison of enthusiasm and superstition
Simon, I get the bit about the sample size probably being small, but they still got a statistically significant result, so do not quite understand that. Can you elaborate? Thanks
What a woefully designed study. I don'tknow how these studies get off the ground in the first place. Surely somebody pointed out the flaws in the methodology? Moreover, who then decides this is worthy of presentation? Too much of this at the moment, at best it is misleading.
Simon,
I really think we need to not be so critical about research such as this. Let's give these authors a break since it was not a published study, instead it was presented at the ACSM meeting as a lecture. The study size was small, but the results seem consistent with what I see clinically in treating many foot and lower extremity injuries with foot orthoses of all types: customized pre-fab orthosis do quite well short term at treating many foot and lower extremity injuries.
I use pre-fab orthoses every day in my practice and customize them for the patient, using the same mechanical principles I use for presription casted foot orthoses. However, since this study does not say anything about long term effects of customized pre-fab orthoses, we can only use it as evidence of short-term effects of orthoses. I believe where custom casted foot orthoses clearly show their superiority to customized pre-fab devices is in their long term clinical efficacy, their long term cost-effectiveness and their nearly unlimited potential for prescription variation to fit the patient's specific biomechanical and shoe style requirements.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Simon, I get the bit about the sample size probably being small, but they still got a statistically significant result, so do not quite understand that. Can you elaborate? Thanks
Not sure why you don't understand how they can "get a significant result" just because sample size is small? "Getting a significant result" does not mean the sample size is adequate. Without disrespect to anyone, this statement by DaVinci speaks volumes regarding the general confusion about statistics and research methods I meet among the majority of colleagues. This is why I believe that such critique by those with a greater understanding of research and statistical methods on forums such as this are important. Whether this was published or disseminated at conference is perhaps irrelevant to the moot point. How many people attended the conference and walked away with the opinion that what the researchers were saying was fact? Ultimately, how many people will be mislead on the basis of this under-powered, poorly designed study? Anyway, sample size is only one aspect of the methodological weakness here.
Lets take the opening statement:
"Foot orthoses are common interventions that are often intended to increase performance, reduce deformity, and improve pathology. Although prefabricated foot orthoses (PFO) are less expensive and more readily available than custom foot orthoses (CFO), the latter are more customizable. Which intervention provides superior functional outcomes is unclear."
So if we forget the first two statements which are themselves contentious and focus on the final line which sets out the authors aim for the study: that is to determine which intervention (prefabricated or custom orthoses) provides superior functional outcomes.
They take 19 subjects from somewhere unknown, by methods undisclosed, with a variety of unknown conditions and split them into two groups:
"Subjects with lower extremity overuse injuries were randomized to receive either PFO’s (n = 9) or CFO’s (n = 10),"
So from this we have no idea which conditions were being treated by which type of orthoses or their frequency within each group. So the preform group could have consisted of nine people with plantar-fasciitis, while the custom group could have been made up of ten subjects each with different pathologies. For example: trochanteric bursitis, illio-tibial band friction syndrome, osteoarthritic pain in the knee, chondromalacia patella, patella tendonitis, medial tibial stress syndrome, Achilles tendonosis, Sinus tarsi syndrome, Peroneal tendonitis or any other combination of the multitude of pathologies which may classified as "lower extremity overuse injuries"
What if all the subjects in the PFO group were female and all in the CFO group men?
What if all the subjects in the PFO group were aged 18-25 years and all in the CFO group were aged 65-75 years?
So we have a potential problem with the subject groups here- we may not be comparing like with like. But here's the real kicker:
" in combination with out patient physical therapy interventions as required."
So they wanted "to determine which intervention (prefabricated or custom orthoses) provides superior functional outcomes", but they are also giving the patients physio as required. This clouds the issue and the ability for the researchers to determine which effects are attributable to the foot orthoses and which are due to the physio.
Now lets assume that "out-patient physical therapy interventions are not the same for all "lower-extremity over-use injuries; that the outcomes obtained by physio's applying their techniques to this wide variety of pathologies is not the same for all pathologies; that the same physio-therapist did not administer said treatments; that some of the subjects received this treatment while others did not; that some subjects received one physio session, while other received multiple treatments etc etc. There then exists a massive potential for drawing the wrong conclusions and you start to see big problems in the methodology. It could just be that the information posted is insufficient for a reasonable critique of the methods, but when the layman reads this.....
To be fair to the researchers they do conclude
"Prefabricated foot orthoses, in conjunction with outpatient physical therapy interventions".
But hey, I'd love to ask them a one word question: Sure?
__________________ Science is the antidote to the poison of enthusiasm and superstition
Not sure why you don't understand how they can "get a significant result" just because sample size is small? "Getting a significant result" does not mean the sample size is adequate. Without disrespect to anyone, this statement by DaVinci speaks volumes regarding the general confusion about statistics and research methods I meet among the majority of colleagues. This is why I believe that such critique by those with a greater understanding of research and statistical methods on forums such as this are important. Whether this was published or disseminated at conference is perhaps irrelevant to the moot point. How many people attended the conference and walked away with the opinion that what the researchers were saying was fact? Ultimately, how many people will be mislead on the basis of this under-powered, poorly designed study? Anyway, sample size is only one aspect of the methodological weakness here.
Lets take the opening statement:
"Foot orthoses are common interventions that are often intended to increase performance, reduce deformity, and improve pathology. Although prefabricated foot orthoses (PFO) are less expensive and more readily available than custom foot orthoses (CFO), the latter are more customizable. Which intervention provides superior functional outcomes is unclear."
So if we forget the first two statements which are themselves contentious and focus on the final line which sets out the authors aim for the study: that is to determine which intervention (prefabricated or custom orthoses) provides superior functional outcomes.
They take 19 subjects from somewhere unknown, by methods undisclosed, with a variety of unknown conditions and split them into two groups:
"Subjects with lower extremity overuse injuries were randomized to receive either PFO’s (n = 9) or CFO’s (n = 10),"
So from this we have no idea which conditions were being treated by which type of orthoses or their frequency within each group. So the preform group could have consisted of nine people with plantar-fasciitis, while the custom group could have been made up of ten subjects each with different pathologies. For example: trochanteric bursitis, illio-tibial band friction syndrome, osteoarthritic pain in the knee, chondromalacia patella, patella tendonitis, medial tibial stress syndrome, Achilles tendonosis, Sinus tarsi syndrome, Peroneal tendonitis or any other combination of the multitude of pathologies which may classified as "lower extremity overuse injuries"
What if all the subjects in the PFO group were female and all in the CFO group men?
What if all the subjects in the PFO group were aged 18-25 years and all in the CFO group were aged 65-75 years?
So we have a potential problem with the subject groups here- we may not be comparing like with like. But here's the real kicker:
" in combination with out patient physical therapy interventions as required."
So they wanted "to determine which intervention (prefabricated or custom orthoses) provides superior functional outcomes", but they are also giving the patients physio as required. This clouds the issue and the ability for the researchers to determine which effects are attributable to the foot orthoses and which are due to the physio.
Now lets assume that "out-patient physical therapy interventions are not the same for all "lower-extremity over-use injuries; that the outcomes obtained by physio's applying their techniques to this wide variety of pathologies is not the same for all pathologies; that the same physio-therapist did not administer said treatments; that some of the subjects received this treatment while others did not; that some subjects received one physio session, while other received multiple treatments etc etc. There then exists a massive potential for drawing the wrong conclusions and you start to see big problems in the methodology. It could just be that the information posted is insufficient for a reasonable critique of the methods, but when the layman reads this.....
To be fair to the researchers they do conclude
"Prefabricated foot orthoses, in conjunction with outpatient physical therapy interventions".
But hey, I'd love to ask them a one word question: Sure?
Simon:
Good points. I guess I just figured that they didn't list all their methodology in their abstract for brevities sake. If they don't list it, do we know they did it incorrectly or should we assume they did it correctly? I don't get too excited about research by just reading abstracts. Abstracts just gives me an idea of whether I want or need to read the full paper or not.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
If they don't list it, do we know they did it incorrectly or should we assume they did it correctly?
We just don't know and that is the key. But they do make clear conclusions here. Researchers should be mindful of the fact that most will only ever see the abstract.
__________________ Science is the antidote to the poison of enthusiasm and superstition
We just don't know and that is the key. But they do make clear conclusions here. Researchers should be mindful of the fact that most will only ever see the abstract.
Good point again, Dr. Spooner. Yes, we have seen other studies lately on customized pre-fab orthoses that were listed in the abstract as only being "pre-fab" orthoses. The lesson is that we should read the whole paper before we jump to too many conclusions.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Agreed. Moreover, we should ensure we obtain and maintain the skills required for critical engagement with the literature.
Something more for me to do in my old age, Dr. Spooner?
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
On the topic of engaging research literature can you recommend reader friendly articles / texts which might be suitable specifically for the Podiatrist? I am thinking here in particular about a cohort of practitioners who wish to apply critical evaluation in their everyday work, but do not have the benefit of PhD education to drive their curiosity.
On the topic of engaging research literature can you recommend reader friendly articles / texts which might be suitable specifically for the Podiatrist? I am thinking here in particular about a cohort of practitioners who wish to apply critical evaluation in their everyday work, but do not have the benefit of PhD education to drive their curiosity.
Dieter and all,
The series of articles published by Trisha Greenhalgh in the BMJ are an excellent free resource:
Thank you for the link. I believe I have a copy of her book - must dust it off and take another look.
I bet someone, somewhere has constructed a 'dummy's guide' to interpreting research findings - this would be ideal for the busy clinician.
I was reminded of this by Simon's systematic deconstruction of the above research.There are specific, key points to look at whenever a research paper appears and usually it is possible to establish in about 1 minute just how robust is the methodology, etc.
Can someone perhaps recommend similar for statistical analysis?
Dieter
I have found the following JAPMA papers quite useful in the past
Redmond A. C., Keenan AM, (2002) Understanding Statistics Putting P-Values into Perspective, J Am Podiatr Med Assoc 92(5): 297-305
Redmond A. C., Keenan AM, Landorf K, (2002) ‘Horses for Courses’: The Differences Between Quantitative and Qualitative Approaches to Research, J Am Podiatr Med Assoc 92(3): 159-169
Keenan AM, Redmond A. C (2002) Integrating Research Into the Clinic. What Evidence Based Practice Means to the Practising Podiatrist, J Am Podiatr Med Assoc 92(2): 115-122
RCT comparing prefabricated to custom made foot orthoses
Linear Mode
