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Born with club feet which were corrected by means of plastering within the 6 months of age. Current age 67 years. Suffering feet and ankle pain for over 3.5 decades. Habitual of a routine post dinner walk for about 3-4 km everyday. No pain killers used. Pain is normally bearable but sometimes gets severe and is normally relieved to bearable limits by warm water bath / contrast bath. Recent podiatric/orthotic investigation suggesting Charcot Feet.
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@Priyanka Sindwani
Thanks, ma'am. I'll be obliged if you could please advise the strengthening and stretching exercises.
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There are contradictory recommendations in this regard. Any authentic guidelines please?
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No role for rapping with aluminuum foil in getting pain relieve.
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Does the term "contrast bath" imply any random time-temperature combination of hot and cold water or it is a specific combination of repetitive alternate spells of dipping the affected body part in cold water at a specific temperature for a specified duration followed by dipping in hot water at a specific temperature for a specified duration?
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Dear Mr. Shanker Lal, I largely agree with the earlier responders. A contrast bath is the immersion of the extremity under consideration alternatively (for a minute or two) in hot and cold bath for at least 15 min per sitting. Though the literature suggests water in cold container to be between 10-15 degrees C and water in hot container to be between 35-45 degrees C, it may be kept at the tolerance level of the individual.
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After the ORIF surgery of right hand wrist fracture, the fingers are stiffened - the finger segments getting as hard as stones (hardened edema) - making the bending of fingers to close the palm as fist almost impossible as the stone hard lower segment of the finger doesn't allow the finger to be bent downwards. The physiotherapist tries mobiisation applying his full might to bend the fingers downwards causing extreme pain to the patient, still the fingers do not bend beyond 90 degrees from their fully stretched position. Is this physiontherapy (extreme torture to the patient) - extending to 2 / 3 / 4 weeks or even more - the only way to restore the fingure movement or there are some easier / painless patient-friendly ways (such as some medication etc.) of treating the stiffened fingers without subjecting the patient to ubearable tortures?
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There may be various reasons for stiff fingers following wrist surgeries such as lack of occupational therapy and complex regional pain syndrome (reflex sympathetic dystrophy syndrome) . Best option is to start graded occupational therapy combined with wax therapy . If the stiff ness associated with pain ,then always need to suspect CRPS. so treat accordingly with various measures including drugs and therapy. It would be a long course to get normal functional hand.
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Biomechanics face grand challenges due to the intricacy of living things. We need multidiciplinary approach (mechanical, chemical, electrical, and thermal ) to unravel these intricacies. We need to integrate observations from multiple length scales - from organ level to, tissue level, cell level, molecular level, atomic level, and then to energy level) Over these intricacies, their dynamism, the complexity of their response makes it very difficult to correlate empirical data with theoretical models. Among these challenges, which is the most important challenge. If we solve the most important challenge, we could solve most of the other challenges easily.
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Biomechanics is both Art & Science because it does not follow Newton's Three Primary Laws predictably. I can stop rolling down a hill biomechanically at will. A bird can fly away when dropped from a tree as opposed to an apple or a piece of gold of the same mass.
The main problem that I have encountered in researching and practicing biomechanics clinically is that its researchers and clinicians are deterministically trying to study it quantitatively (Science) when n=1, there are too many variables to do so. The best that can currently be done is to study it stochastically (Art) or some hybrid of both (Art & Science).
When studying mankind biomechanically we need to seek disruptive biomechanical theories with new terminology and methods of research, diagnosis and treatment. Ones that consider the myofascial organ, the endocannabinoid system and the true actions and purpose of the CNS and neural strategy.
We need to abandon subtalar joint neutral, pronation and "normal" for words that lead us to a better understanding and control of human stance and movement efficiently and without injury or degeneration.
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Thanks for the answers...
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Hi,
What I understood is that an upper-knee amputation post infection + life threatening medical assistance + multiple sequential amputations caused a fat embolism.
I meant that in post-infected ans scared tissues with possible weak veins, it is hazardous to restrict the embolism entry to the shaft marrow since is seems there was no material pushed inside in the bone shaft; such insertions may cause fat embolism.
For upper knee amputation, by definition, we loose a lot of weight, which is changing the remaining thigh balance in the side coronal plane, since the femoral offset is not changed. Too much correction has consequences for sure.
Soft tissues tend to "melt" very quickly. Then we tend not to strip muscles (they will turn into fat) and fat regarding the bevel bone cut. And in fragile tissues, it is important not to have too tight tractions one the skin causes by the stitches. It may cause succion troubles in the prosthesis but it is another problem.
Talking about shoes, a bare foot has a lot of fat pad regarding metatarsian heads and ever stronger shell at the heel (very useful in Syme's amputation).
Cheers, JM.
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Joint pain is a very common problem with many possible causes - but it's usually a result of injury or arthritis.
Due to the fact that anxiety can increase long term stress, the risk of of inflammation is high. I think This inflammation can cause pain and swelling in joints, affecting every day movements.
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Please take a look at the following PDF attachment.
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I am searching about PEEK cage and I need references for all aspects of mechanical design or test about it.I wanna know more about optimization factors for this device.
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Dear Elahe,
This publication may be a good start for mechanical properties of PEEK implants.
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How can i determine the upper limit of storage temperature for metal implants, UHMWPE implants with or without crosslinked structure? During packaging, storage, transportation etc. the temperature changes in a wide range. When i look at the raw material standards (ISO 5832-1, 5832-3 etc.) or the general specification standards of nonactive surgical implants (ISO 14630, ISO 21534 etc.) and specific standards of surgical implants (ISO 21535, ASTM F1378 etc.), i cannot see any ideal temperature condition statements. How can i verify the upper temperature for at least storage stage?
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Oleksandr Oleynik Thank you so much, I thought that before, now I'm sure. Also there are some sort of specifications about sterile storage.
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Tibial fractures are the most common long bone fractures.The aim of treatment for tibial shaft fractures is function with lower complication rates. Several methods have been used for treatment of this fracture, including compression plating, reamed or unreamed intramedullary nailing and external fixation. Among them, intramedullary nail fixation has been shown to be an effective method for treating both open and closed tibial fractures . However, the choice between two alternative intramedullary nailing approaches, reamed or unreamed, is an ongoing controversy. Reamed intramedullary nailing has the advantage of providing optimal biomechanical stability; however, reaming of the medullary canal may also lead to endosteal blood flow damage, bone necrosis, compartment syndrome and infection . In theory, unreamed intramedullary nailing does not have the above-mentioned problems associated with reaming, but the mechanical stability may limit its application. Both of them have strong rationales; which is better?
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Unreamed nails are kmown to sustain fatigue fractures if used at the wrong indication. They are not the panacea.
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The tibia is the most commonly broken major bone in the leg. Displaced distal tibia shaft fractures are effectively treated with standard plates or intramedullary nails. which one is more preferable?
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Please find attached some recent literature opinions
Effect of Locking Plate Fixation vs Intramedullary Nail Fixation on 6-Month Disability Among Adults With Displaced Fracture of the Distal Tibia
The UK FixDT Randomized Clinical Trial
Matthew L. Costa, PhD; Juul Achten, PhD; James Griffin, MSc; Stavros Petrou, PhD; Ian Pallister, MMedSci; Sarah E. Lamb, DPhil; Nick R. Parsons, PhD; for the FixDT Trial Investigators
JAMA. 2017;318(18):1767-1776
A comparison of the cost-effectiveness of intramedullary nail fixation and locking plate fixation in the treatment of adult patients with an extra-articular fracture of the distal tibia. Economic Evaluation Based on the FixDt Trial
M. Maredza, S. Petrou, M. Dritsaki, J. Achten, J. Griffin, S. E. Lamb, N. R. Parsons, M. L. Costa
Bone Joint J 2018;100-B:624–33.
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Bone fracture is the most common effect in osteoporosis. one the reason is the impact of osteoporosis on the density of the cortical bone. So I'm looking for the role of the density disorder which is caused by osteoporosis in bone fracture.
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Hi Dear Sophie,
Thank u very much. I'll chock out it for sure.
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It's clear, osteoporosis has a direct impact on bone density. How can I figure out the manner of this effect in spongy and cortical bone, separately?
On the other hand, I'd check out how this effect of osteoporosis changes the orientation of bone blades?
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Dear Mehrshad,
on elf the best reviews in the field of cortical and trabecular bone adaptation due to osteoporosis is the following one
Kind regards,
Ramona Ritzmann
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Most of the amputees are suffering from the secondary disorders which are more common in upper extremity one. There is more pressure on upper limb amputees’ intact hand since they have to do every single task just by one hand and this imbalance causes musculoskeletal problems such as scoliosis. Despite doctors advice, due to the difficulties of prosthetic hands uses especially in above elbow cases, some of the amputees desist from using it, after a while. I want to know if cosmetic prosthetic really prevents spine deformity like scoliosis?
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Intramedullary nailing has revolutionized the treatment of fractures. It is important to be aware of the biological and mechanical effects of reaming and nailing on bone. Intramedullary devices commonly are termed rods or nails.
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Intramedullary nails are ideal for diaphyseal long bone fractures and mostly closed fractures are managed by reamed nails. Reaming is supposed to ensure thicker nails to be introduced that is better and stronger. Reaming also is supposed to provide interosseous bone grafts as reaming byproduct assisting Union of Fracture. However in open fractures reaming is withheld as it increases chances of prolonged surgery and chances if fat embolism syndrome. Intramedullary nail in emergency setting is thus a norm.
Reaming was also thought to interfere with intramedullary blood supply but no proven data is present till now.
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Knee locking refers to when the leg gets stuck in one position, making it impossible to bend or straighten it. It may only last a few seconds, it may last longer. It all depends on what is causing it. Most cases fall into one of two categories.
There is true locking caused by a mechanical block where something gets stuck inside the joint, preventing movement. This type most commonly occurs as you move the knee into full extension, i.e. towards being fully straight.
Secondly, there is pseudo locking, caused by severe pain which temporarily limits movement in any direction.
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Unclear about the question. Although in the text is described that the locking is mechanical (due to loose bodies or meniscal and ACL tear) when usually the knee locks in flexion or the pseudo-locking, when the knee usually locks in extension, the logic of the question was demonstrated in a clear way. The common reason for pseudo-locking is patello-femoral pathology (degeneration of the articular surface of the patella or the trochlea or in rare conditions the existence of a thick plica, folding of the synovium). Nothing of all this is influenced by the diet, except if the amount of food that is consumed is excessive and is resulting to obesity. This is the only case that diet can influence the knee locking. Dietary habits can influence the uric acid and so the potential gouty synovial reaction and consequently arthritis, but this is another matter.
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In simple fractures it's better to put the screws away from the fracture site to have enough elasticity but in crushed fractures or long ones, screws can be placed near the fracture site to reduce implant tension in the area. What causes this tension?
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Hi Fateme,
Let me see if I understand your question, you mean two cases: (1) for simple fractures, the screws should be placed away from the site; (2) for long or severe fracture, the screw should be placed at the site; Are those two scenarios you want to distinguish? if it is, my answer this may be directly related to the crack growth and intensity factors, but since you did not provide enough details about what is the shape of crack.
the long crack has more sensitivity to the displacements, bending, or torsion since the intensity factor is higher, so the crack is much easier to grow that the small cracks. To place the screw near the crack tip or opening can actually reduce the growth of crack. However, for the simple and small crack, to reduce overall stress or strain is much better than put screw near it since it did not induce new deformation for it.
Best,
Junchao
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In what situation which one is better and totally can we say which one is better?
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Although the use of reamed IM nails for the management
of femoral shaft fractures has been associated with
overall excellent clinical results, concerns about the biological
consequences of reaming have increased interest in the
femoral nailing technique without reaming. Femoral
nailing with reaming has been associated with high union
and low implant failure rates, but the reaming process has
been thought to generate bone marrow embolization phenomena,
disrupt of cortical blood flow, and theoretically
increase the risk of infection, particularly in open fractures.
On the other hand, the use of smaller-diameter unreamed
nails has raised concerns about rates of fracture healing
and implant failure.
As per recent cochrane review
Recommendations
• The use of unreamed femoral nails is associated with a
significant risk of delayed union compared with reamed
nails [overall quality: high]
• With respect to other union complications (non union,
implant failure), no significant superiority of the reamed
over nonreamed nails was proven [overall quality:
moderate]
• Reamed femoral nails were not associated with a significantly
higher risk of developing pulmonary complications
compared with nonreamed nails [overall quality:
moderate]
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A short femoral stem is a desirable hip implant for bone and soft tissue preserving hip replacing surgery in young arthritic patients. Physiological loading of the proximal femur prevents stress shielding and preserves bone stock of the femur in the long run. Since
the life service of hip prosthesis is less than the longevity of young patient and they 'll need to revision total hip replacement , the short stem prosthesis is better for them.
But are there any another advantages for short stem over standard stem?
And whether do they cause the standard stem will be useless?
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Previous studies demonstrated that both short cementless stem and conventional cementless stem provided stable fixation and achieved a satisfactory result in patients 70 years and older and the short cementless stem had a low incidence of thigh pain and intra-operative fracture.
J Orthop Surg Res. 2016; 11: 33.
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A short femoral stem is a desirable hip implant for bone and soft tissue preserving hip replacing surgery in young arthritic patients. Physiological loading of the proximal femur prevents stress shielding and preserves bone stock of the femur in the long run.
Since the life service of hip prosthesis is less than the longevity of young patient and they 'll need to revision total hip replacement , the short stem prosthesis is better for them.
But are there any another advantages for short stem over standard stem?
And whether do they cause the standard stem will be useless?
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Daer Dharmshaktu
thank you so much.
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I really need useful sources to differ these things and answer to this question which way is better.
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Reaming where we drill the intramedullary canal so we can insert large size diameter nail because stability Is found to be associated with diameter of nail . Large size diameter is more stable . So the golden standard practise is to use reamed nail in long bone. Fracture . Un reamed nail mean small diameter of the nail and so it less stable . We use it when the bone quality is poor and situation of patient is not good and life expectancy I'd low as in cases of pathological fracture. .
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I really need some sources to describe this obviously .
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Here are the things that we need to know in design:
characteristics of the proximal and distal ends of these devices
Intramedullary nail systems at the proximal, middle, and distal regions need to have their strength and flexural rigidity (stiffness) evaluated
Test strength and stiffness between the middle and the proximal or distal aspects of rods.
Strength and rigidity which increases with rod diameter
Static strength
Mechanical properties (bending rigidity)
You need to know the characteristics of strength and rigidity for the particular devices available and how these might impact fracture healing.
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What mechanical stimulation should have biomechanical properties for severe fractures to have a positive effect?
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Wish there were straightforward answers to your question. Let's see how best we can go about it.
Different stages of fracture healing need different level of mechanical stability as well as stimulation.
During fracture healing, the initial stages involve cellular proliferation. The predominant stimulus for proliferation is perfusion. Mechanical stimulation affects cell differentiation and depends on the strain magnitude and the cell phenotype. As a consequence, today's implants should be applied in a fashion that supports maximum perfusion at the fracture site. In the early period, the osteosynthesis should facilitate micro-motion of the fragments if secondary fracture healing is desired. At the same time, joint congruency, and axial and rotational positions have to be maintained. In the final period of healing, motion within the calcifying callus should be limited, which is naturally achieved by the increasing stiffness of the callus ossification.
You may find the following articles useful:
The complexity of the topic may be judged from the fact that there are PhD thesis being done on it. One of them is
Hope this helps.
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In leg amputation the remained bone is rasped to make the edges smoother to avoid tissue injuries. but still there is an unusual structure underneath the skin. 
Why don’t we use an implantable structure to avoid abnormal structure like sharp edges and damp the undue pressure and shocks underneath bones, the same way heel fat pad*(HFP) protects the underlying structures in the heel?
From my point of view, using such implants might also ease the use of prosthetic legs and decrease the possible pain in leg- prosthetic interfaces.
Are there any specific reasons not to use such implants during the leg amputation?
*The heel fat pad (HFP) is a highly specialized adipose-based structure that protects the rear foot and the lower extremities from the stress generated during the heel-strike and the initial support phase of locomotion. HFP cushioning efficiency is the result of its structure, shape and thickness.
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Bevelled bone end + adequate thickness of myoplasty should do the trick. Implant on the bone end is not necessary especially if the prosthesis is not designed to receive weight transmission through the end stump. If we worry about bad soft tissue surrounding the bone end, putting an implant on that area will create more problems, such as rapid implant wear, infections. Higher amputation level with good soft tissue should be put into consideration.
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there are mobile bearing vs fixed bearing, cruciate retaing, PCL retaining, posterior stabilized, medial pivot prosthesis and etc. Companies including Zimmer, Stryker, Microport (Wright) and etc. Which one do you think is better and what are the reasons?
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Rising health care cost has very little to do with the individual cost of implants.Insurance companies, purchasing agents and even health care administrators are very short sighted when it comes to cost containment. They are more interested in what they can save on this years budget compared to reducing actual health care dollars.
I would suggest saving O.R. time and being efficient in the O.R. will reduce O.R. time and turnover time saving more money than the price of any third world implant.
It is estimate in the U.S, that O.R. time can cost between $150 to $300 per minute. The most effective action surgeons can take is to do what you do best with the equipment you know best. The cost of a revision wipes out any potential implant discount one receives. Reduction of health care cost is  achieved in improved long-term outcomes not short term discounts.
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Most health disparity and joint replacement (knee, hip) I've seen look mainly at African-American and Non-Hispanic Whites.  Anyone aware of papers or researchers looking at Asian-Americans?
Thank you!
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Thank you!
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I want to calculate the maximum tendon stiffness. I know that it corresponds to the slope of the force-length curve in the linear region. However, the limits of linear region are a little subjective. So, which method do you suggest me to set objectively this linear region?
I read a method where the authors defined the linear region "...as the one in which the least-squares-fitted line had the correlation coefficient value of 0.98" (Link: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2907260/#R5) but in this method there is a lack of objectivity too. I was thinking in define some percentages as 25 - 75% of maximum force and calculate the stiffness there, but i didn't found researches that support this.
Thank you!
Pd: Sorry for my english, i'm trying to improve it!
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Thank you very much! Very useful information :)
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I thank colleagues for their suggestions. In annex x-ray images, clinical did not seem to be a problem of rotation. Our decision not to operate because of the fear of possible postoperative .. .prolonged the same legs works of accelerated growth, and at the same time we are not sure that our decision is correct
best regards, 
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Boy or girl ? If girl- what about menarchy ? In any case the oblique pelvis is a problem making the centering of the femoral head problematic (degenerative changes later in the years). As far as I understood the decision was already made for "wait and see" tactics. So monitoring, measuring the dynamics of the LLD. If the condition (LLD) does not imrove (after 6-12 months) then corrective valgus osteotomy should be discussed earlier or later.
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Can you please suggest plan of management for 2 months old polytrauma in 18 year old morbidly obese lady, who sustained a complex pelvic # with bilateral feet drop? Should we try to salvage this hip with an attempt at ORIF or do a primary THR?
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We did post. and ant.fixation in the same sitting. post fixation was very difficult due to scarring.
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We are analyzing the walking behavior and wanted to know the forces required while doing regular jobs. I know that these data is quite complicated and varies from person to person. However, there will be a simpler way to analyze such forces.
It would be of a great help if you can help us out.
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What's the name of distal phalanx pseudarthrosis, due to interposition of ungueal matrix?
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Yes, I agree, Seymour's fracture
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I am trying to develop a  new test rig to measure mechanical changes in natural cartilage (glenoid) against humeral cup with different material. I have read a a lot of papers but they work on implant on implant or reverse shoulder arthroplasty. Do you know any groups that might do similar work to my project? 
Thank you! 
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I',m attending to a study about the effect of the Cunningham technique for shoulder dislocation, but I need more relevant referrences. Please contact me if you have any full texts of them. Thanks a lot!!!
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Neil Cunningham, MBBS, FACEM. "Cunningham Technique". Shoulderdislocation.net.
Walsh, R; Harper, H; McGrane, O; Kang, C (2012). "Too good to be true? Our experience with the Cunningham method of dislocated shoulder reduction". The American journal of emergency medicine. 30 (2): 376–7. doi:10.1016/j.ajem.2011.09.016. PMID 22100465.
Cunningham, NJ (2005). "Techniques for reduction of anteroinferior shoulder dislocation". Emergency medicine Australasia : EMA. 17 (5–6): 463–71. doi:10.1111/j.1742-6723.2005.00778.x. PMID 16302939.
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I've been reading through the literature to create a biomechanical model of counterforce brace effects.  Right now I'm working on the Jumper's Knee strap, and I'm not finding a lot of biomechanical evidence for symptom relief, only a lot of anecdotal clinical accounts.  I was wondering if anyone has published a paper or read a study with more concrete evidence.  This is a little different than the load/force redistribution effect of the tennis elbow counterforce strap...
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Hi Sarah, I helped with a study that found that these patellar straps decrease the mean localized computational strain in the area of the patellar tendon commonly involved in jumper's knee by increasing the patella-patellar tendon angle.  Michael
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Does vascularised fibula achieve significantly better union rates than non vascularised fibula for segmental bone defect?
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in long grafts where the distal end is not aimed for fusion, in distal radius GCT, vascularised bone graft can prevent fibular graft resorption. In other cases extended immobilisation gives the same result
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Dear Respected Researchers,
Analysis of Structural Interactions between bone and bone screws.
I have generated the screw model and imported it to design modeler where I created the bone model and used boolean subtraction to create the screw imprint/threads inside the bone. On getting to the Set-up, the contact elements or connection is solid-to-solid and which gave me excessive stress Von-Mises stresses after running the simulation. I have tried to  change it surface-to-surface, rigid-to-flexible contact elements on ANSYS Workbench but to no avail. THANK YOU!
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Dear Muhammad, in Workbench is implemented a thread contact tool that can help you, instead of draw the thread. It is better define a surface-to-surface contact. Anyway if you draw the fillet I suppose you can define a frictional contact, with an asymmetric contact. Or maybe the load is too high. Rigid-to-flexible is not a contact property you can defined only by Joint connection: I'm not sure if you mean this. 
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Hello
I would like to test the hip flexors and extensors isometric strength in supine position using the Biodex System 4. These are my options:
1. Set the starting position at 45 degrees so I can test both muscle groups simultaneously. This may give me optimal performance of both muscle groups.
2. Test the hip flexors at 0 degrees and the hip extensors at 90 degrees of hip flexion as a starting position. 
Which position is best? If you have other suggestions kindly let me know.
Thank you
Mohamed
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Dear Mohamed 
First of all, do you mean of best for subjects comfort or for analysing data?
If you mean for analysing data make sure to choose starting position which isolate your group muscles that you want to evaluate from other muscles.
Secondly, try to be sure that all the muscles of the muscle group that you want to test are active in that starting position.
In addition, it is better to use a position which is used before in previous studies, otherwise you have to justify why you used this starting position.
I hope my answer will give a hint for choosing starting position.
All the best 
Mohammad Alali
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Recently, we had a case of 21yo woman with severe hallux valgus and flatfoot. We tried Lapidus procedure (TMT I arthrodesis and lateral release WITHOUT intermetatarsal stabilisation) and subcapital chevron derotational osteotomy for DMAA correction. Due to traction of the EHL effect was stil unsatisfactory. We decided to add the Akin procedure in the proximal phalanx as a "last hope" procedure. Cosmetic effect seems good. Do you have any experience with this method or do you do try anything different in such cases?
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I do chevron mostly, sometoimes with a very long plantar cut (similar to scarf);  akin just as needed. If the TMT1 is instable, I fuse it. Otherwise the foot biomechanic is altered and a stiff gait results, pushing arthrosis.
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Many surgeon recommend single bundle due to the easiness of the tech. and to avoid weakening of the patella, on the other hand double bundle i see it more close to normal bio-mechanics?  
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In regard to children with open physis the quadriceps tendon technique and the adductor magnus transfer are my favorites. 
Quadriceps tendon: no fixation in the patella needed. Fixation on the femur with an anker avoiding the growth plate. 
MPFL reconstruction using a quadriceps tendon graft: part 1: biomechanical properties of quadriceps tendon MPFL reconstruction in comparison to the Intact MPFL. A human cadaveric study.
Herbort M, Hoser C, Domnick C, Raschke MJ, Lenschow S, Weimann A, Kösters C, Fink C.
Knee. 2014 Dec;21(6):1169-74. doi: 10.1016/j.knee.2014.07.026. Epub 2014 Aug 7.
PMID: 25178693 Free Article
Adductur magnus tendon transfer: no anker/screw needed at the femoral side (no risk for growth plate) and only one fixation point at the patella (no risk for patella fracture)
Arthroscopy. 2012 Dec;28(12):1749; author's reply p. 1750. doi: 10.1016/j.arthro.2012.08.010.
Reconstruction of the medial patellofemoral ligament using the adductor magnus tendon.
Sillanpää PJ, Arendt E.
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There are still controversial opinions. What is your experience ? What combination wears less and slowly ? 
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I agree with all comments presented so far however I do want to caution that this issue is now broader than just wear of the bearing surface. We are seeing taper issues arising that are effecting the performance of bearing material. I am attaching some photos of a recent explanted Accolade  femoral hip stem made of TMZF.
This proprietary beta titanium alloy offers 25 percent greater flexibility than Ti-6Al-4V alloy, yielding a modulus of elasticity that more closely resembles that of bone. In addition, TMZF maintains a 20 percent higher tensile strength than Ti-6Al-4V alloy.
This greater flexibility has presented problems with the neck/head taper. You will see in the photos attached that the stem taper has deformed resulting in lost contact of the femoral head. This material used with larger femoral offset and larger head diameter has contributed to device failure.
So the lesson learned is to be diligent in product selection and make sure you have the best information available. ( Errors are made by all manufactures regardless of size or longevity of the company).
Regards,
Tim
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Does anyone know if there is a difference with elbow extension torque or force production with a pronated vs. supinated forearm?  Does scapular position make a difference?  When trying to isolate triceps folks will often hold the arm in adduction (dips, cable pushdowns, etc.)  Is this just a perceived benefit or is there objective data supporting?
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Two important considerations are relevant here:
1. Pronating the forearm 90 degs will create the ideal length tension relationship for triceps contraction during elbow extension
2. By adducting the glenohumeral/shoulder joint, the triceps long head angle of pull is enhanced 
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I need to know what is the taper(conical) angle in pedicle screw of vertebra.
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I have found this angle a bout 3 or 4 degree in different manufacturer companies that have substantiated on attached paper.
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Traditionally the patella fracture with intact extensor apparatus has been treated by cylinder cast, long knee immobilizer brace as well as percutaneous lag screw. 
But is there any evidence in the literature as to what is the best mode of treatment?
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In completely non-displaced patella fx's, I keep patients in a ROM brace x 3weeks locked in full extension, allowing for showers, bathing, etc.  Range of motion 0-30 at 3- 6 weeks, then progress as tolerated. 
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I am looking into whether a mathematical model of the hip joint exists to determine contact area to allow me to calculate hip joint stress. Models exist for the patellofemoral joint, is anyone aware of models that are available for the hip.
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Dear dr. Sinclair,
we have developed and validated (by clinical studies) models for resultant hip force in the one-legged stance and for contact stress in the hip,  reviews are given in the links below
The weight bearing area is defined in the model for stress.
There are more publications at
original papers with the models are from 1993 and 1999.
In the homepage of the Laboratory of Biophysics there is also software HIPSTRESS, however it runs only in older computers. We will update the software, meanwhile, the nomograms can be used which are in the first link above.
If you would like to use the models and you need help please let me know, kraljiglic@gmail.com
V. Kralj-Iglic
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I know that a large proportion of the muscles in the body are active for a person during her/his gait. But I'm not sure exactly (or approximately) the value of the proportion in percentages with a valid reference.
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The proportion of the muscles active during gait not permanent, but many factors affect on the percentage of muscle contribution during gait such as age, walking speed, fitness, injuries, deformities, etc....... However, the following papers maybe help you to answer of this question.
Anders, C., Wagner, H., Puta, C., Grassme, R., & Scholle, H. C. (2009). Healthy humans use sex-specific co-ordination patterns of trunk muscles during gait. European Journal of Applied Physiology, 105(4), 585–594. http://doi.org/10.1007/s00421-008-0938-9
Arnold, A. S., Anderson, F. C., Pandy, M. G., & Delp, S. L. (2005). Muscular contributions to hip and knee extension during the single limb stance phase of normal gait: A framework for investigating the causes of crouch gait. Journal of Biomechanics, 38(11), 2181–2189. http://doi.org/10.1016/j.jbiomech.2004.09.036
Arnold, A. S., Thelen, D. G., Schwartz, M. H., Anderson, F. C., & Delp, S. L. (2007). Muscular coordination of knee motion during the terminal-swing phase of normal gait. Journal of Biomechanics, 40(15), 3314–3324. http://doi.org/10.1016/j.jbiomech.2007.05.006
Arnold, E. M., & Delp, S. L. (2011). Fibre operating lengths of human lower limb muscles during walking. Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences, 366(1570), 1530–9. http://doi.org/10.1098/rstb.2010.0345
Bonnard, M., Camus, M., Coyle, T., & Pailhous, J. (2002). Task-induced modulation of motor evoked potentials in upper-leg muscles during human gait: A TMS study. European Journal of Neuroscience, 16(11), 2225–2230. http://doi.org/10.1046/j.1460-9568.2002.02295.x
Finch, L., Barbeau, H., & Arsenault, B. (1991). Influence of body weight support on normal human gait: development of a gait retraining strategy. Physical Therapy, 71(11), 842–855; discussion 855–856.
Goldberg, S. R., Anderson, F. C., Pandy, M. G., & Delp, S. L. (2004). Muscles that influence knee flexion velocity in double support: Implications for stiff-knee gait. Journal of Biomechanics, 37(8), 1189–1196. http://doi.org/10.1016/j.jbiomech.2003.12.005
Gordon, K. E., Sawicki, G. S., & Ferris, D. P. (2006). Mechanical performance of artificial pneumatic muscles to power an ankle-foot orthosis. Journal of Biomechanics, 39(10), 1832–1841. http://doi.org/10.1016/j.jbiomech.2005.05.018
Hicks, J. L., Schwartz, M. H., Arnold, A. S., & Delp, S. L. (2008). Crouched postures reduce the capacity of muscles to extend the hip and knee during the single-limb stance phase of gait. Journal of Biomechanics, 41(5), 960–967. http://doi.org/10.1016/j.jbiomech.2008.01.002
Ivanenko, Y. P., Cappellini, G., Poppele, R. E., & Lacquaniti, F. (2008). Spatiotemporal organization of ??-motoneuron activity in the human spinal cord during different gaits and gait transitions. European Journal of Neuroscience, 27(12), 3351–3368. http://doi.org/10.1111/j.1460-9568.2008.06289.x
Ivanenko, Y. P., Poppele, R. E., & Lacquaniti, F. (2004). Five basic muscle activation patterns account for muscle activity during human locomotion. The Journal of Physiology, 556(Pt 1), 267–82. http://doi.org/10.1113/jphysiol.2003.057174
Ivanenko, Y. P., Poppele, R. E., & Lacquaniti, F. (2004). Five basic muscle activation patterns account for muscle activity during human locomotion. The Journal of Physiology, 556(Pt 1), 267–282. http://doi.org/10.1113/jphysiol.2003.057174
Komura, T., & Nagano, A. (2004). Evaluation of the influence of muscle deactivation on other muscles and joints during gait motion. Journal of Biomechanics, 37(4), 425–436. http://doi.org/10.1016/j.jbiomech.2003.09.022
Kuhtz-Buschbeck, J. P., & Jing, B. (2012). Activity of upper limb muscles during human walking. Journal of Electromyography and Kinesiology, 22(2), 199–206. http://doi.org/10.1016/j.jelekin.2011.08.014
Meyns, P., Bruijn, S. M., & Duysens, J. (2013). The how and why of arm swing during human walking. Gait and Posture. http://doi.org/10.1016/j.gaitpost.2013.02.006
Michel, V., & Do, M. C. (2002). Are stance ankle plantar flexor muscles necessary to generate propulsive force during human gait initiation? Neuroscience Letters, 325(2), 139–143. http://doi.org/10.1016/S0304-3940(02)00255-0
Petersen, T. H., Willerslev-Olsen, M., Conway, B. a, & Nielsen, J. B. (2012). The motor cortex drives the muscles during walking in human subjects. The Journal Of Physiology, 590(Pt 10), 2443–2452. http://doi.org/10.1113/jphysiol.2012.227397
Piazza, S. J., & Delp, S. L. (1996). The influence of muscles on knee flexion during the swing phase of gait. Journal of Biomechanics, 29(6), 723–733. http://doi.org/10.1016/0021-9290(95)00144-1
Pijnappels, M., Van Wezel, B. M. H., Colombo, G., Dietz, V., & Duysens, J. (1998). Cortical facilitation of cutaneous reflexes in leg muscles during human gait. Brain Research, 787(1), 149–153. http://doi.org/10.1016/S0006-8993(97)01557-6
Riley, P. O., & Kerrigan, D. C. (1998). Torque action of two-joint muscles in the swing period of stiff-legged gait: A forward dynamic model analysis. Journal of Biomechanics, 31(9), 835–840. http://doi.org/10.1016/S0021-9290(98)00107-9
Schipplein, O. D., & Andriacchi, T. P. (1991). Interaction between active and passive knee stabilizers during level walking. Journal of Orthopaedic Research, 9(1), 113–119. http://doi.org/10.1002/jor.1100090114
Shelburne, K. B., Torry, M. R., & Pandy, M. G. (2006). Contributions of muscles, ligaments, and the ground-reaction force to tibiofemoral joint loading during normal gait. Journal of Orthopaedic Research, 24(10), 1983–1990. http://doi.org/10.1002/jor.20255
Steele, K. M., Seth, A., Hicks, J. L., Schwartz, M. S., & Delp, S. L. (2010). Muscle contributions to support and progression during single-limb stance in crouch gait. Journal of Biomechanics, 43(11), 2099–2105. http://doi.org/10.1016/j.jbiomech.2010.04.003
Winter, D. A., & Yack, H. J. (1987). EMG profiles during normal human walking: stride-to-stride and inter-subject variability. Electroencephalography and Clinical Neurophysiology, 67(5), 402–411. http://doi.org/10.1016/0013-4694(87)90003-4
Yungher, D. A., Wininger, M. T., Barr, J. B., Craelius, W., & Threlkeld, A. J. (2011). Surface muscle pressure as a measure of active and passive behavior of muscles during gait. Medical Engineering and Physics, 33(4), 464–471. http://doi.org/10.1016/j.medengphy.2010.11.012
Regards, 
Abdel-Rahman
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Man of 58 years-old with trauma (D12 vertebral fracture, fractured left shoulder blade, multiple rib fractures on the left). The scapular fracture treated with immobilization for 30 days (orthopedic). The patient has undergone neurosurgery of reduction / stabilization of the fracture with screws transpedicular D12 D11-D12 L1e kyphoplasty (duration surgery - 1 hour and 25 minutes, anesthesia duration - 2 hours and 15 minutes). The patient was placed in the prone position with the head resting on blankets and turned to the left. Immediately after the operation, during arousal, the patient experienced pain in the left eye, edema and amaurosis. He underwent angiography which showed signs of retinopathy in both eyes and a central retinal artery occlusion in the left eye (CRAO).The patient is diabetic with insulin pump therapy, hyperlipidemic (rosuvastatina), hypertension, occasional smoker or former smoker, hyperhomocysteinemia, assumes Cardioaspirin. The doppler has revealed a thickening of the left carotid artery with a fibro-calcific plaque without significant impairment of flow. In addition, both the CT that the brain MRI showed multiple small areas of gliosis of the white matter, as from vascular cerebral disease. According to your experience, could the prone position to have been the only cause of ocular damage? 
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Bone fracture, post op immobilisation , DM , hyperlipidaemia, carotid plaque etc has the potentiality to develop thrombus and or embolus which can cause blockage of arteriole on their  circulating path way. We ophthalmologist often keep our patient in prone position following VR surgery. There is hardly any report  of CRAO following such procedure. I also agree w other responder that positioning of the patient has not caused CRAO. 
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There may be altered joint arthrokinematics and other mechanical issue of an adjacent structure, which may contribute to lateral knee pain. So, what will be the best physiotherapy management?
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Hi Peter,
Very informative..... Thanks a lot.
Warm regards,
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It is known that Hippocrates had developed a "surgical" technique to stabilise the commonly presented anterior dislocation of the shoulder. In the modern medical era we have developed and abandoned many procedures. Which of them do you think imitates the original Hippocratic technique?
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Thermal capsuloraphy is usually performed arthroscopically now days. In my humble opinion the ancient technique cannot be compared totally with this.
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I am doing finite element analysis of knee joint.I have considered the contact between meniscus and femoral/tibial  cartilage to be no separation (with finite sliding) in ANSYS workbench .
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All depends on the study's aim. If this is a static model with the knee in extension and vertical loading then the mentioned concept of non separation can be considered. If on the other hand there will be joint motion within the analysis then due to the "presence of articular fluid" can be considered frictionless, as the presence of friction can be considered "negligible". In this case though this has to be mentioned as a limitation to the study.
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For what reason and benefit would someone train legs in isolation from one another, what effects & improvements would be seen and what advantages are found?
Suggestions of, Medical journals &/or technical papers on movement/function/mechanics/positions of the body would be welcome.  
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The biggest reason I can think of is from sports perspective. As a majority of sports involves dynamic movement which includes pivoting and moving on a single leg, unilateral leg work can come in handy.
The approach is two-fold: 1. To strengthen the dominant leg, 2. To strengthen the weaker leg. I have personally observed this in soccer players where the dominant leg is stronger and muscular than the other leg. However, in the mechanics of kicking a ball, planting the other foot is way more important before the other leg begins to kick. Therefore, having a stronger 'weaker' leg is very essential in the mechanics of kicking. 
The other reason I can think of is aesthetics in terms of bodybuilding. Under the assumption that we have a dominant leg, the goal is to develop the non-dominant leg to the aesthetic standard of bodybuilding. If a two legged leg exercise like squat is performed, the dominant leg will be performing majority of the work. Therefore, a one legged exercise one legged smith machine exercise can target the individual leg. 
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I am doing Finite element analysis of knee joint to investigate the effects of meniscectomies on  knee biomechanics
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Partial: when a part of the meniscus is removed (anterior or posterior horn or middle part of the body or part of the whole length of  the meniscus mainly at the white zone, for example after removal of a bucket handle tear)
Subtotal: when the removed part of the meniscus is near to the red zone and involves the whole length
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A patient had been subjected for ORIF for  supracondylar  fracture distal femur 5 months earlier, he is presenting with stiff knee to 30 degrees flexion and with no active quadriceps contraction.
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If we presume that no malunion with a major angle between the fragments in the sagittal plane exists, then arthrolysis (adhesions release) followed by systematic rehabilitation should yield good functional results. 
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A new development in both TSA and RSA have been convertible stems; in both applications, the same humeral stem is used. Newer designs allow the same stem for total, reverse, and fracture cases (previously, a separate stem was needed for total and fracture for conversion to reverse). Since the neck-shaft angle is more varus for primary or fracture applications, this affects the position when converted to reverse.
Boileau et al reported that since convertible systems require an onlay humeral cup as opposed to an inlay humeral cup used in Grammont-style prosthesis, this led to humeral lateralization.
My question then is are there any convertible shoulder designs that avoid humeral lateralization?
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Dear Yusuf
Great question. The idea to create the convertible modular components came from the failure of either the reverse shoulder replacement (around the glenoid , and the need to convert this to a "conventional" total shoulder) or mainly the failure of the "conventional" total shoulder replacement or hemi-arthroplasty (mainly due to soft tissue "incompetence" and loss of movement and the need to give this movement back by utilising the deltoid). For the second option the conventional component is converted to reverse prosthesis and the soft tissues are paramount to give the joint stability. As they "failed" (usually it is the failed rotator cuff) there is the need to "balance" them and the lateralisation of the whole humerus may be of necessity to do so. The main problem is the potential impingement of the greater tuberosity on the acromion. Such an effect can be changed by the position and the size of the stem in a position which will eliminate the impingement. Hope this will be helpful to you.
Best wishes
George
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Diagnostic criteria for upper cross syndrome?
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The Upper Cross Syndrome is mainly the result of muscle imbalance (Dorsal Upper Body muscles are getting weaker and the Upper Trapezius and Sternocleidomastoid are going to tension) This postural "deformity" is resulting to the head to move forwards and be within  the upper quadrant of a side leaning cross or shape of X.
So the main diagnostic criteria are based on history and the clinical picture.
Patients are complaining of Headache, Shoulder pain, Muscle aches and Pain in Upper back and Neck.
Clinical picture (Postural Changes):
Forward head posture
Increased cervical lordosis and thoracic kyphosis
Elevated and protracted shoulders (Rounded shoulders)
A hunched upper back
Rotation or abduction and winging of the scapula
This position can result to Degeneration of the Cervical Vertebrae and the AC Joint at the Shoulder area, occasionally resulting to shoulder impingement.
Test: Janda test: Patient supine tries to elevate the head from the couch. Normally the lordosis will disappear and the chin will touch the sternum. Otherwise pathological picture shows that the head is lifted with the very tense sternocleidomastoids.
So the diagnosis is done only based on clinical grounds.
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Does anyone know if there is consensus in this topic?
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Yes, difficult cases. Anyway,the results are worth doing it. Cooperation with haematologist for substitutional therapy with the factor which is absent in the individual case is indispensable (timing, dosage, time to discontinue, good lab control). Please, see some references below. 
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patients presented with severe pain in their fingers after wearing rings of different metals for along period .the pain increased with movement . no allergy from metals. the joint movement is restricted slightly.
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finger diameters change during day due to work, climate conditions and many other factors. Thus it is understandable that this results sometimes in a lymphatic jam  or nerve-compression.
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Hi all! as a part of a study about the Ponseti procedure for the treatment of the congenital clubfoot  I’m analyzing the correlation between two different scores (Pirani and Dimeglio) and the number of casts required to achieve the correction. I used Spearman rho (normality could not be assumed as the K-S test indicated the p-value of less than .05 for all the items) and found that  both Pirani and Dimeglio are significantly associated to the number of casts, and almost collinear between them (Spearman’s rho = .875); but how to determine which is better in terms of predictability? May I use linear regression or what else? Thank you all for your suggestion
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You are welcome!
Good luck!
Rainer
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I am a physical therapist who specializes in the treatment of facial palsy and TMD.  We are finding a very high incident of those patients that are slow to recover have as preexisting condition of TMD.  Looking for collaborators to investigate the mechanism of the link.
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- Are there different risk factors for each one?
- Why some people have one or the other lesion?
- What are the main etiological differences?
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 I fully agree with the complete answer given by Prof. TANCHEV... Not much more to say about that and all the answers are given...
The best to U all!
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We know that after hip surgery some parts of the artificial joint is separated because of the load pressure and immune defense cells  secrete toxic substances to destroy foreign bodies .this  material absorbs most of the bones in the place of joint and weakens the connection .it causes the second surgery.so how can we reduce it?
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The problem is tackled nicely by both the authors above and it is well analysed. In your description is mentioned that "some parts of the artificial joint is separated because of the load pressure and immune defence cells  secrete toxic substances to destroy foreign bodies".
These reactions happen with either polyethylene debris coming from the friction between the plastic acetabular cup and the metallic or ceramic head, or more recently with the metal ion debris from the metal on metal articulations. The metal on metal though is reduced if not completely abandoned following a series of failed arthroplasties throughout the world. Ceramic on ceramic produce some ions that for the moment are not blamed for any secondary problems. Also the use of "hard" polyethylene shows good resistance to failure.  Multiple factors can increase the failure rate and some of them are the weight of the patient and the occupation as increased loads may increase the wear and tear.
Reactions due to the material used "per sei" can be due to the presence of polymethyl-methacrylate (bone cement) which has particular substances within it, as chlorophyll and this may affect the people who are allergic to peanuts or in some cases of patients who are allergic to nickel if the component has this ion. Despite that these latter reasons are mentioned in the everyday clinical practice there is not enough broad evidence in the literature to support them.
Finally I agree that if there is a "solid" and "impenetrable" fixation at the level of the metaphysis at the bone prosthesis interface and if all the biomechanics as mentioned are fulfilled the prosthesis has long life.
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Application: athletic tape
Preferred fabric: cotton or cotton blend
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I do know what you mean about the perks of cohesive tapes like Victory tape.  But many trainers want the traditional cotton tape, and we still need to cater to that population. Until cohesive products gain traction with users, we will have to work with the traditional cotton tapes.  That doesn't mean I don't want to improve them, though!  And I'm always looking for outside perspective, helps to design "out of the box" so to speak.  
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In hip replacement surgery orthopedic surgeon inner surface of the acetabular cavity in the pelvic area that has been corrupted to make a full hemisphere. A hemisphere-shaped metal bowl placed inside the cavity. Inside the metal bowl placed a polyethylene plastic bowl. Sometimes plastic bowl without metal bowl attached into the acetabulum cavity by bone cement .
In some cases it has been observed that after a few months or a few years, polyethylene is causing loosening of the artificial joint and bone fractures.
We want to know how the bone fracture affects polyethylene.
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This should be because the mechanical properties such as modulus (Young's modulus) of the  artificial material is not matching with that of the native bone tissue. Therefore, there will be more load transmitted to the bone segments, especially in interface. This will cause resorption of bone and finally the loosening of implant and could lead to fracture of bone. Similarly if we use a material which has higher modulus than the bone, then the material will bear all the load , transmitting very low or no load to the bone (mechanical (stress)shielding effect). This is also detrimental (mechanical stimuli is necessary for healthy living bone) , in a longer period,  on the bone implant interface  and cause resorption of bone, thereby loosening of implant and fracture of bone.
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In the study of intervertebral disc degeneration, many animal models are being used to mimic human disc degeneration. However, the degeneration in these models is generally induced by directly damaging the intervertebral disc structure or applying high mechanical forces. These methods can't cause endplate calcification, which paly an important role in human disc degeneration. Is there any aged animal model that could develop endplate calcification in intervertebral disc? (Besides the shot tail rat) Or any technology can induce endplate calcification in commonly aviliable animals?
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The only animal model / experiment that showed early degeneration of discs and endplates was done around 1902 by the German Orthopedic Surgeon Wullstein , in which he gave young dog puppies a garment in which the spine was forcefully flexed and kept like that for a certain amount of weeks. 
The animals were offered and the spines researched in which the duration of the applied shearforces on healthy discs proved to have a linear relation with the grade of detoriation/ degeneration of especially the thoracolumbar spine. 
These studies enhanced the implication  of better preventive measurements in the youth in Germany and later in West Europe to stay away as much as possible in flexed positions of the spine (as is inevitable in sitting, the modern life allday lifestyle) . A forgotten tool in Medicine. 
So it is more about shearforces by the sedentary lifesstyle leading to bad postures than overload in activities that depict nowadays the early degeneration of the human spine. 
Of course genetic based characteriscs of the primary cells (resilience, elasticity etc) make a difference in the fenotype that  evolves out of this combination of internal and external factors. 
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I am interested in obtaining physiological loading and boundary conditions applied on the femur, especially during walking activity. I read some papers saying that femoral head deflects towards the knee joint center. I need to verify if this information is 100 % correct or if it is just coming from common sense. Appropriate references would be great.
Thanks.
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It looks like that this pathology seems misdiagnosed and mistreated in some countries all other the world. Nevertheless, the responsibility of this structure seems well established and, as far as I know, there is no doubt about it's responsibility for severe anterior knee pain, osteomalacy, osteochondritis or severe impingement.
What is your feeling about it and which therapeutic options are yours for these specific pathological situations: fast and easy arthroscopy or conservative treatment?
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Thank you Lauren for this very good answer. I do agree with most of these relevant points even if I'm now much more aggressive with this recurrent pathology... Some authors confirmed that point and on my own experience results of arthroscopic debridements are really good... Nice day!
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I am looking for the actual forces required to cause fractures to the various different regions of the facial and skull bones.  If you could share some info/ literature on that would be of great help (either general or specific to motor vehicle accidents).
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Hello Vigneswaran,
The book by Nahum in the second link provided by Aamir is very comprehensive regarding the literature on head and facial trauma. Additionally you might find these two articles helpful.
Melvin1995-a biomechanical face for the hybrid III
Tarriere1981-field facial injuries and study of their simulation with dummy
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In a few cases I had to... Mostly for cases with severe PRE-OP lateral tibial plateau instability with relevant positive JERK test, in order to avoid POST-OP PL instability as well as to protect my transplant. Somme of our Colleagues systematically associate this technique to their IA surgery. What is your experience about it and which technique do you use for it?
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In cases where the difference in laxity (AP laxity) in monopodal view is more than 10 mm, at the athlete patients and where the pivot shift test is too important.
In these cases evaluation of the dynamic rotator instability is very important. 
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I would need a good reference form literature, from which to get a clear description and motivation of how to calculate hip range of motion in swing and maximal/minimal hip flexion.
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Dear Erika
These articles may be useful for you
1) J Sports Sci Med. 2007 Jun; 6(2): 154–165.
Published online 2007 Jun 1.
PMCID: PMC3786235
Biomechanical Characteristics and Determinants of Instep Soccer Kick
Eleftherios Kellis✉* and Athanasios Katis*
2)  Atlas of Limb Prosthetics: Surgical, Prosthetic, and Rehabilitation Principles  - Chapter 13   -  Normal Gait - Jacquelin Perry, M.D
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Does anyone have experience in treatment of hip luxation in konradi syndrome?
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Dear Ali
Conradi-Hünermann syndrome is a rare genetic disorder characterized by skeletal malformations, skin abnormalities, cataracts and short stature. The specific symptoms and severity of the disorder may vary greatly from one individual to another
The treatment of Conradi-Hünermann syndrome is directed toward the specific symptoms that are apparent in each individual. Such treatment may require the coordinated efforts of a team of medical professionals, such as pediatricians; physicians who diagnose and treat disorders of the skeleton, joints, muscles, and related tissues (orthopedists); skin specialists (dermatologists); eye specialists; and/or other health care professionals.
Various orthopedic measures, including surgery, may be recommended to help prevent, treat, or correct certain skeletal abnormalities associated with the disorder. Surgery may also be advised for certain craniofacial malformations, scoliosis or other physical abnormalities. The surgical procedures performed will depend on the nature, severity, and combination of anatomical abnormalities, their associated symptoms, and other factors.
Genetic counseling may be of benefit for affected individuals and their families. Other treatment is symptomatic and supportive.
I dont have experience with this syndrome but i think the treatment of hip dislocation, when indicated, should be similar to the treatment of teratological  congenital hip dislocation . The conservative treatment does not provide good results. Surgeries can range from removal of soft tissue interposition, through femoral osteotomy and pelvic osteotomies
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Hello dear researchers... I need to learn specific values of tendon excursion and resting tonuses of Extensor carpi ulnaris, Extensor carpi radials longus and brevis, extensor digitorum communis, extensor pollicis longus and abductor pollicis longus tendons. proximal to the wrist. It'll be highly appreciated if the data is provided along with their flexor counterparts.
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This is what the book looks like.  I apologize that when I took those pictures it was from a borrowed book of one of my professors that I no longer have.  I hope this is helpful.
MBG
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I want to create a finite element model of the thoracic spine. After looking at the literature, I realized that some detailed (in terms of muscle complexity, attachment sites, etc.) lumbar and cervical spine models exist, but thoracic spine is not somehow (although a few studies look at the thoracolumbar spine). I will be thankful if you suggest me where I shall begin, and direct me to studies from where I can get data regarding muscle anatomy acting on the thoracic spine with their attachment locations.
Regards.
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 Can we export these spine models into other platforms such as abaqus and ansys or are they restricted only to OpenSIm
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I am looking for collecting health survey scores for Orthopaedic patients in UK via SF12. I got both SF12 V1 and SF12 V2. It looks like SF12V2 is better to use.
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I suggest to contact the Mapi Research Trust. They have extensive experience and expertise Re. PROs. Go to
"http://www.proqolid.org/" and search for "SF-12".
Or go to
"http://mapigroup.com" and go to "services" and "Mapi Research Trust" => "PROQUOLID".
I have very good experiences with Mapi and recommend to contact them directly. They are very friendly and helpfull.
Cheers, Ernst
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In some patients we observe an oblique joint line (i.e. in cases of a femoral valgus which is compensated by a tibial varus deformity) even though the overall alignment of the affected leg is straight. Does anybody know papers on the biomechanical influence of an oblique joint line in such patients ?
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Panayot is right here: if the femur is valgus and the tibia varus the ligaments and cartilage in the medial compartment of the knee are overloaded under weight and that destined for alteration.
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