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I am studying force transmission through the synovial layer of the knee and would like to dissolve the fat pad so that I can see the fibrous array. Does anyone know of a solution that allows one to do this?
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Hi Tom,
I know this was a long time ago, but I'm wondering if you ever found an answer to your question? I am trying to harvest the synovial membrane surrounding the knee from bovine and porcine stifle joints, but have a hard time surgically separating the fat pad from the membrane and have been wondering about a solution to dissolve as well.
Thanks for any advice you can provide!
Warmly,
Jenn
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particularly for patients after knee surgery, is there evidence to support whether it is best for rehabilitation and functional range of motion to elevate the affected lower extremity with or without support under the length of the lower extremity
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Great Question. Following Knee Surgery, I have found after working with many post operative knee patients, while in bed, supine, that it is best to avoid placing objects such as pillows under the knee, as this may decrease knee extension ROM. Several strategies that have worked is to place foam wedge between the mattress and the box spring at night and/or have someone elevate the front of the bed posts by placing small wood pieces, thus at night the leg/knee remain straight yet elevated. The leg remaining higher than the head while sleeping. The result is less edema and a knee that is able to be straight.
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Arthroscopic Partial Meniscectomy (APM) is one of the most popular orthopaedic procedures, but recent publications stated that non-operative treatments have similar results to arthroscopic surgery.
The Meniscus Consensus Project in which more than 80 physicians from 21 european countries have been involved was set up to try to standardize an uniform the treatment algorithm of degenerative meniscus lesions (DML).
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Mechanical symptoms = arthroscopic menisectomy. Otherwise, treat as osteoarthritis.
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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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I am currently comparing 3 different internal fixation techniques in mandibular osteotomy. My results are grouped into stresses in fixation and surrounding bone, and displacement of proximal segment under 6 different loading conditions.
What would be the best statistical test to compare the results between each fixations and how significantly different are they.
So far, I haven't come across any similar FEA studies carrying out any statistical analysis.
 Appreciate any feedbacks given. Thank you!
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Hi Muhammad: I think for starters it would be helpful to state your hypothesis....what is it you want to learn from this experiment? Then I agree with Robert that it's not clear what your outcome variable is....is it movement distance in mm or area of gap between bone segments in mm-sqrd? Or what?
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Hi All,
I am looking for various ways to analyse medio-lateral control of the knee joint during single-leg landing following a hop. There are few methods suggested by Roos et al. (2014). I would appreciate hearing some suggestions, on this, from the members of ResearchGate.
Roos PE, Button K, Sparkes V, van Deursen RWM. Altered biomechanical strategies and medio-lateral control of the knee represent incomplete recovery of individuals with injury during single leg hop. Journal of Biomechanics. 2014;47(3):675-80.
Thanks,
Ashok
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Thank you Dr. Bhattacharya for your suggestion. However, this study has analysed variables that are not specific to medio-lateral control of the knee during single-leg hop! Indeed, the aims of their study were different though.
Best regards,
Ashok
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Trying to measure procurvatum of the tibia in patients with blount disease, clinically using goniometer (not on the radiograph).
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Mechanical Axis Deviation of the Lower Limbs: Preoperative Planning of Multiapical Frontal Plane Angular and Bowing Deformities of the Femur and Tibia.
PALEY, DROR M.D., F.R.C.S.C.; TETSWORTH, KEVIN M.D.
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Whats your take on this modality of fixation? Is it rationale or just a fad?
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I have used Synthes (calcaneal) mesh plate for severely comminuted patella fractures (off-label). You can essentially fix each comminuted fragment through a plate hole - preserves the fragments with good fixation. However, the overlying skin is very thin and patients will feel the subcutaneous hardware, which may pose a symptomatic problem.
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I'm mostly interested in whether X-ray or MRI was used, whether operated or contralateral knee was measured and which parameters were considered.
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Hi
Usually MRI images are considered for meniscus implant sizing for better precision. These articles may help you,
Thanks and regards,
Mamatha
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Hello.
I am trying to define the limit or threshold of the knee varus-valgus angle (rotational range) for normal subjects. please suggest good references for me.
It seems cadaveric studies, in vitro, are best.
Best regards: Tserenchimed.
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I understand now.This topic is important intraop during TKA and when you explore a patient in the office ( TKA stability).I will try to read the articles above.Thank you!
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Sometimes during the surgical procedure for TKR, one comes across hypertrophied synovium especially in suprapatellar pouch. I have only occasionally excised the synovium. Should it be excised as a routine or not, or what is the indication to remove it?
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I routinely excise the hypertrophied synovium in the suprapatellar pocket because it can be source for inflammation and a stubborn and very troublesome  synovitis postoperatively. It is important to excise only the synovial membrane and leave in situ the prefemoral fat tissue. Sometimes both structures are removed together which can lead to restricted ROM postoperatively.
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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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I have edited the guidelines of AAOS in a tabular form for a ready referral. The opinion of arthroplasty surgeons, please.
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Fast track surgery
1. everybody ASA 1 to 3
2.LIA with epinephrine (if no contraindic)
3. tranexamic acid i.v. 
4 Tourniquet = no problem
5. No Drainage
6. Mobilisation and stand and walk on 3 hours after  surgery
7. not fasting more than 6 hours and sugar beverage 250cc two hours before surgery
8. physio Programm at Hospital after 3 hours
9. discharge at day 2-4
9.  patient preoperative nurse consultation
What are the best practices for TKA in 2016? - ResearchGate. Available from: https://www.researchgate.net/post/What_are_the_best_practices_for_TKA_in_2016 [accessed May 25, 2016].
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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'm trying to find some test to asses knee stability different to Star Excursion Balance Test. I'm interested in any test which can be proved with athletes who have been undergone to a ACL operation and can be performed at field.
Thanks so much
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Hi Olga
I think cross over hop test is the best choice (depending on our experiences).
regard
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Hello,
I am trying to design a new knee implant for a project. Are there some calculations which can be done to determine the thickness of the femoral and tibial components? I know that I can design and then test for deflection using FEA, but I am trying to find also some calculations which can be used to approximate the behavior of the femoral and tibial component when subjected to some stress.
Any information given, will be greatly appreciated.
Robert
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Thanks for your reply. I will do some research on Ranawat. Thanks again.
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I wonder why the jigs used to size the femur have varying degrees of external rotation angles 3-9 degrees attached to them when we know that we need cut at angle of 3 degree external rotation. How do we measure the external rotation with jigs when we have a lateral or medial posterior condyle wear?
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Dear Karthick,
Rotation of the femoral component during total knee arthroplasty (TKA) is to achieve the following:
1) A rectangular flexion gap
2) Optimum patellofemoral tracking
Keeping in mind your question, it is important to know that the following discussion is assuming that the reference axis is the posterior condylar line/ axis (PCA) and the surgeon uses measured resection philosophy (and not gap balancing) during TKA.
Although, it is true that 3 degrees external rotation (ER) is commonly used during TKA, it would be incorrect to presume that only 3 degrees ER is required. The following will elucidate why 3 degrees ER is commonly used. 
Anatomical studies have shown that the mean medial proximal tibial angle is 87 degrees (3 degrees lesser than 90). During TKA, we aim to put the tibial component perpendicular to the tibial mechanical axis (90 degrees; i.e; 3 degrees additional to its natural alignment). Three degrees ER of the femoral component is hence required to rectangularize the flexion gap. If that is not done, we will have a trapezoidal flexion gap. This results in eccentric loading of the insert and patellar maltracking. Thus due to anatomical variations, 3 degrees ER may not be applicable to all. It is likely that after setting 3 degrees ER on the jig, the surgeon may observe that the rotation is inadequate and may opt for greater (or sometimes lesser) rotation. It should also be noted that, the femoral component rotation only seldom affects the size of the femoral component. Hence, the sizing and ER of femoral component must be viewed separately as such.
To answer second part of the question, if the femoral condyles are worn, one can use the transepicondylar axis or the Whiteside's line to determine rotation. If those landmarks are obscured too, one can use the linea aspera to determine femoral component rotation (as it is sometimes done during revision TKA). If you are using a jig that is based on PCA, you can remove the foot pedals that sit on the posterior condyles (usually detachable). Most systems will have inbuilt or additional attachments to the jig to aid reference the rotation off the epicondyles or Whiteside's line. If not, you can always ask the implant rep to arrange one for you.
Hope that helps.
Kind regards,
Sid
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Orthopedic surgeons in India are using both slow eccentric and rapid eccentric (isolytic) stretches in rehabilitation following hip and knee surgery (see attachment). I am interested to discover the mechanisms associated with these methods, particularly relating to intra -and inter- muscular connective tissue structures.
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I"d like to see studies comparing the 15 sec time of stretching with longer times as 60-90 seconds.
Another issue is the intensity of the stretching that is abstract and dificulty to evaluate.
Very good paper, Congratulations.
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Biomet (before its merger) was introducing a product called the Vanguard XP that preserved both the PCL and ACL. The product's indication was expected to be limited, which is why I believe the product has now been shelved after the merger.
My question then, to researchers and clinical practitioners, is how often is the ACL intact in patients with indications for total knee replacement?
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1. Johnson AJ; Howell SM; Costa CR; Mont MA. The ACL in the arthritic knee: how often is it present and can preoperative tests predict its presence? Clin Orthop Relat Res. 2013 Jan;471(1):181-8, doi: 10.1007/s11999-012-2505-2.
BACKGROUND: TKA with retention of the anterior cruciate ligament (ACL) may improve kinematics and function. However, conflicting reports exist concerning the prevalence of intact ACLs at the time of TKA. QUESTIONS/PURPOSES: Therefore, we asked: (1) what was the ACL status at TKA; (2) what was the sensitivity and specificity of the Lachman test; (3) did MRI ACL integrity correlate with intraoperative observation; (4) did MRI tibial wear patterns correlate with ACL integrity; and (5) did ACL status depend on age or sex? METHODS: We evaluated 200 patients for ACL integrity at the time of TKA. All patients underwent a Lachman test under anesthesia. Intraoperatively, the ACL was characterized as intact, frayed, disrupted, or absent. In 100 patients, MRIs were performed, from which the ACL was graded as intact, indeterminate, or disrupted, and the AP location of tibial wear was categorized. RESULTS: The ACL was intact in 155 patients (78%). The Lachman test alone had poor diagnostic ability. The MRI predicted a tear, but we observed two ACLs with indeterminate status that were disrupted. All knees with anterior wear on the medial tibial condyle had an intact ACL (n = 45), and all knees with posterior wear on the medial tibial condyle had a disrupted ACL (n = 8). CONCLUSIONS: Although the Lachman test alone had poor sensitivity, when combined with MRI they together provide a sensitivity of 93.3% and specificity of 99%, which we believe makes these reasonable tests for assessing ACL status in the arthritic knee.
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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 want to know the relation of severity with the specific clinical findings of crepitus sound.
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An interesting question. Years back I started my career with this question.  We tried to record the sound from the joint using a microphone attached to the knee - an experiment not entirely successful. 
Crepitus apparently has no direct relationship to knee OA. It frequently decreases when a knee becomes inflamed or has fluid in the joint, a common occupancy as knee OA becomes more severe. 
Best best in can be an early sign of OA if it is present. 
Siddharth Das 
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For those who prefer intra-medullar guiding, have you ever noticed post-operative complications (whatsoever)?
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Thank's you guys for these nice and interesting answers. As far as I can see from my own experience, most of our Colleagues mostly use unique extra-rod to check both slope and tibial angle. This is not my preference and as Prof. TANCHEV said, I fully agree with Prof. FERON's answer which is certainly the most clever issue to that problem...
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Thanks in advance for your replies.
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There is no such thing like ultimate head diameter in ceramic-on-ceramic THA. The diameter ranges from 28,  32 and 36 mm (Zimmer Biolox). Usually ceramic bearings with large diameters are not available because of some specific limitations of ceramics.
I would say that the surgeon must decide what diameter to use. In some patients, sizing considerations may necessitate the use of an acetabular component with a relatively small diameter. For such patients, a large-diameter ceramic femoral head may not be an option. Large-diameter femoral heads reduce the risk of hip dislocation and are favored in modern hip surgery. Unfortunately, because of design limitations related to material properties, ceramic heads are available in only a limited range of femoral head diameters; in similar cases the surgeon choosing a larger-diameter femoral head may have no choice but to use a metal head.
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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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For example, I'm looking specifically for arthroscopic knee surgery outcomes.
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Knowing that arthroscopy is an approach and not a treatment procedure, I would first need to know what is being treated and how. As others have stated you should also define primary outcome tools used to assess outcomes; are you concerned about complications, readmission, and/or patient reported outcomes? Or are you looking for benefits of scope vs open knee procedures? I would recommend searching pubmed for publications from the MOON knee group and MARS group.
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Currently several landmarks are used to identify the joint line level in revision knee arthroplasty. However, I wonder which one is a suitable method? Does anyone have an idea? Thank you for your contributions.
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Dear Dr. Kleuber, in my practive I keep to the approach that you propose. One should try to restore the situation before the first replacement. The preoperative planning for revision should incorporate these data. Unfortunately, this is a difficult task because of bone stock loss at that moment. One should need to restore and augment bone by structural grafts and bone cement. 
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Why is the tibial and femoral component in the Knee implant made of different material? Why can't the femoral and tibial component be of completely Metal or Polyethylene? Does it have anything to do with lubrication?
Could you provide some reference for the same
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@ A.U. Daniels
My demand is published not a secret. It is not the threat and also not the harass. It just when you answer about any question you must be Kind. Please send me apologize. If you don't send me apologize I will report you to Research Gate.  
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Material Chemical and Mechanical Properties.
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Dear Awais
Stainless steel and chrome cobalt are the routine material in orthopedic implant . but hip and knee systems for arthroplasty  had more complex structures. stems usually sprayed with Tivanium 6Al 4V for biologic osteointegration. in some designs porous coated and etc..
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What is the appropriate approach for management for a neglected patella fracture of over a year with the proximal fragment at the region of the mid thigh with weakness in the extensor mechanism.
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I agree with Dr. Farouk. This injury lies back more than a year and the fragments are severely dislocated. The fragments are osteoporotic.  One can try to  mobilise the quadriceps muscle in an attempt to reduce the non-united fragments and fix them but in my opinon this should be difficult if possible at all.
One should then consider patellectomy, quadriceps plasty and transposition of part of the ischiocrural muscles to enhance the extension mechanism. In my practice this prosedure has worked satisfactorally.
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I am trying to find out level of cartilage destroying enzymes which is associated with crepitus sound with pain.
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Crepitation suggests sever chondromalacia (gr II and III). I have no experience with the measuring the level of destroying enzymes.
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Criteria of return to light activities (return to a sedentary job, straight-ahead running) uses commonly a timeline (12-16 weeks postoperatively)?
You use functional test to give your agreement to return to light activities? (Hop tests?)
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Dear Alexandre,
i focused on this problems since a year and a half. There is no objective data for a single criteria to return to sport. The evidence level is IV as reported in:
Barber-Westin SD, Noyes FR. Factors used to determine return to unrestricted sports activities after anterior cruciate ligament reconstruction. Arthroscopy. 2011 Dec;27(12):1697-705. 
There is a lack of evidence although there are a lot of recommendations without scientific background.
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Accidental case
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If you mean eversion of the patella together with the extensor apparatus at knee surgery, there seems to be some evidence, that in all these cases the postoperative flexion is diminished.
Personally I see no difference between cases, where we everted the patella and cases where we did not.
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I am starting work on tibia stress simulation after surgery. I found a validate model of femur. But where I can find an already validated model of tibia to start research on it?
Thanks
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Hi Carlo,
biomedtown, which was suggested by Nishant, my be a very good choice.
Also, you may want to check for a model within the Physiome Project dataset, where you can find the results of a long-lasting and high level project on multiscale modelling, including organ-scale models of parts of the muscolo-skeletal system. You can find those at this url:
Best Regards,
Emiliano
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Is there any defining factors (noted in the first week post op, i.e. analgesia, physiotherapy, swelling) that can predict a patient having ongoing knee stiffness and requiring a MUA post TKR? And therefore any prevention strategies?
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Apart from the usual causes already mentioned, warfarin usage and also the inability to take NSAIDs are the commonest reasons I see clinically for patients not comfortably obtaining 90degrees bend at 6 week follow-up. These patients are frequently in the 80-90 degrees range and if urgent intensive Physio is implemented they can often get over 90 degrees in the next week or two and avoid MUA. This is a different group from the very stiff knees where infection has to be excluded and where pain control issues and severe pre-op stiffness or technical problems with the surgery  are more likely to be implicated.
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We receive such patients who refuse replacement surgery and expect a 100% recovery by PT Rx in terms of pain, function, gait and even joint space and deformity. We try counseling but they keep on complaining.
Do you face such problems? What's your opinion?
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Dear Dhara,
The ultimate goal of exercise in OA is to prevent or delay disability. An exercise program should incorporate elements to lessen pain during activity and to
increase or at least maintain joint range of motion, periarticular muscle strength, joint stability, and aerobic capacity or level of conditioning.
Exercise in OA should be adapted according to the presence and severity of pain.
In painful episodes:
- Isometric exercise or exercise in a non weight-bearing
(e.g., biking, rowing with adapted tools) or
- In a partial weight-bearing position (e.g., aquatic ex) should be recommended.
In painless (or at least less painful) periods:
- Exercise program may include progressive muscle performance exercises.
The above exercise programs may delay disability but does not help regenerationof the cartilage. Hence, it can't recover the actual joint pathology, so the final choise of treatment will remain joint reconstruction or replacement surgery untill we get a new line of treatment.
Regards
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All the available articles investigate acute tournament related traumatic injuries. I am looking for articles describing the wear and tear on the joints from years of karate training.
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Dear Alex
This article may be useful for you:
Br J Sports Med 2005;39:29-
Injuries in martial arts: a comparison of five styles
M N Zetaruk1, M A Violán2, D Zurakowski3, L J Micheli3
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We get neglected cases of OA knee with badly stretched LCL. Weight bearing Xrays show even medial subluxation of tibia with posteromedial bone loss on tibia. The options at surgery include use of metallic wedges/ bone grafting to reconstruct the bone loss combined with intramedullary extension rods in tibia. The option of use of a larger tibial post to provide stability against subluxation is another option. What should be the algorithm of treating such cases?
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This is a great question. I encounter this situation commonly in my uninsured patients that have gone a long time without care.
Many of these knees can be balanced with an implant that does not have varus/valgus constraint but certainly it would be reasonable to have semi constrained implants available as back up. I'll with a standard distal femur cut (the thickness of the implant) regardless of the presence of a flexion contracture. I template the angle of my distal femoral cut and in a situation like this if the templated angle is between 2 degrees I pick the lower number or even a degree less cheating the femur in 0.5-1.5 degrees of varus from the mechanical axis. This will make the knee easier to balance and in my opinion will likely not affect the durability of the knee replacement. The tibia however should be cut perpendicular to its axis. At this point you have to decide how much lateral bone your willing to take and/or how much medial bone you will leave un resurfaced to accomplish this task. With the system I use, downsizing a single size does not require a big lateral shift so I have no problem doing this. Releasing and excising the uncovered medial bone will also greatly facilitate balancing the knee. From the lateral side I don't want to take more than 12mm after which the lateral laxity seems to markedly worsen. If a tibial downsize, slight lateral shift, and a 12mm cut from the lateral side will not give a flat tibia perpendicular to its axis then I will use a 5mm medial block augment along with a short/stubby cemented stem. At this point I'll check the alignment of my tibial cut but I'm not going to try to completely balance the extension space. Given the fexion contracture I'm pretty sure that removal of posterior femoral osteohytes and release of the capsule from the posterior femur will be required so I'll do this before any further releases from the tibia. For the femoral cuts I am a believer in posterior referencing for sizing because I want to maintain native femoral offset. For femoral rotation, I'll use anatomic landmarks for multiple reasons (that is another discussion). At this point I'll use spacer blocks or laminar spreaders to balance the knee. Given the flexion contracture and severe varus most of the release with be posterior. The sequence I will use is first the posterior oblique ligament then semimenbranosous. If I'm still too tight medial in extension a gentle fractional lengthening of the MCL will almost always get me there. I'll use an 18 gauge needle to slowly pie crust the MCL while applying gentle traction and valgus. What I'm looking for in a perfect world is 1mm of opening medial and 2mm of opening lateral. Depending on the patient, Ill accept a little more lateral opening. What I wont accept is a completely incompetent lateral side, more than 2mm of opening on the medial side, or a medial side that is so tight that it is springing open the lateral side. In these rare situations, rather than risk making the medial side completely incompetent, I'm going with short cemented stems, and a semi constrained poly with a thickness that will allow for full extension and no springing open of the lateral side.
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In one of my recent surgeries on an obese female, the extension and flexion gaps (after the releases) were just sufficient enough for the largest insert (17.5) I had available. I was wondering what the options to tackle this situation would be if the gap was bigger.
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In principle for the primary case you don't have such problems. The previous answer is correct to look at https://www.researchgate.net/go.Deref.html?url=http%3A%2F%2Fwww.orthobullets.com%2Frecon%2F5016%2Fsagittal-plane-gap-balancing.
But for this special situation a revision prosthesis is necessary .
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I am a medical student of the University Medical Center of Freiburg, Department of Orthopedics and Trauma Surgery, Germany, working on my thesis concerning anterior cruciate ligament graft remodeling. I would like to know if any of you already measured the crimp length of the original patellar or semitendinosus tendon in light or electron microscopy? I would be very grateful for any help.
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Thank you for your help.
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There are three main types of bone marrow stimulation in the literature; microfracture, abrasion chondroplasty, and drilling. Can anybody tell me why microfracture is overwhelmingly more popular than the other techniques? Does anybody have any references on the results of these different techniques? Or do you use other bone marrow stimulation techniques other than microfracture?
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I often prefer drilling with a 2.5 mm sheath pin at low speed. The defects which are not approachable by the pin, I use microfracture awl, for example most of the tibial defects.
Although it is advocated to keep them non weight bearing for 6-8 weeks, I however, start early weight bearing. I have, although, not performed a histopathology to see the quality of cartilage, a second look arthroscopy due to some other problem, in some patients showed filling of the defects with new cartilage like tissue.
My common indications these days for this procedure is to do it as a part of arthroscopic debridement in elderly patients for osteoarthrosis who are still not the candidates for arthroplasty due to various reasons. The results are satisfactory.
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Some experts say that up to 7 mm full thickness of longitudnal tears, and any length of partial thickness for longitudnal tears reaching to only one surface (femoral or tibial) can be left untouched.
I have always been wary about leaving them behind because I feel they are the trigger points for future extensions.
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Dear Ravi
The treatment of a meniscal injury will depend on its location, size, time of occurrence, age and level of sports activity of the patient. In my opinion, the treatment may be non-surgical for elderly patients with low functional demands and the remaining patients i performl arthroscopic surgery, even with minimal damage because I agree with you that this minimal lesion can evolve and cause more damage than it was
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Do you know of any recent research on this topic?
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Dear Laura
These articles may be useful for you
1) Ann Phys Rehabil Med. 2012 May;55(4):229-40.
Comparison of gaseous cryotherapy with more traditional forms of cryotherapy following total knee arthroplasty.
[Article in English, French]
Demoulin C1, Brouwers M, Darot S, Gillet P, Crielaard JM, Vanderthommen M.
2) J Arthroplasty. 2010 Aug;25(5):709-15.
Cryotherapy after total knee arthroplasty a systematic review and meta-analysis of randomized controlled trials.
Adie S1, Naylor JM, Harris IA.
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Knee replacement and sizes of implant.
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as per available experience, i find all available sizes are reasonably fine. but problem lies with less possible difference in available size in OT
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The extension ROM after TKR has been reported as a negative value, i.e. - 3.2 or -2 in some articles and in some other articles it has been reported as a positive value, i.e. 3.56 , 3.58 . What should we interpret? The authors have not mentioned anything.
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In case of reading the pioneers of total knee replacement as well as if you follow the scoring systems all values must be positive. Any hyper extension has to be reported as a positive value with the addition hyperextention. I am afraid that the confusion started when some health workers than surgeons started to publish their results and started to make negative markings. Following this some of the surgeons followed. So I will urge the authors of any paper to define clearly the ROM in the correct way either the value of their work will be diminished
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I'm currently seeing a patient who is 40 years old and has symptomatic arthritis of the prox tibiofibular joint. The patient is a healthy, active, long-distance runner. Knee and ankle joints are OK. Imaging includes MRI of tibiofibular joint showing typical signs of OA including effusion and some edema in the surrounding soft tissues. No indication of infection of tumor.
Which therapeutic approach do you recommend?
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Dear Michael,
Did you check the subtalar joint biomechanics?
Maybe your patient is presenting hiperpronation during the running stance phase, creating a excessive tibia internal rotation and proximal tibiofibular joint instability and degeneration.
In some cases, specific strengthening exercises (posterior tibialis, gluteus maximus and hip lateral rotartors) could help to provide some improvements. In last case insoles to sustain the plantar arc and provide stability and better lower limb alignment.
Best wishes and good lucky!
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Anterior Cruciate Ligament (ACL) tears of the knee is a very common injury where it can be used different types of grafts to reconstruct a torn ACL such as: BTB (Bone- Patellar Tendon-Bone) autograft, hamstrings autograft, quadriceps tendon (QT) autograft or allografts to reconstruct the torn ligament. But which is your criteria to decide the ideal graft for you patient?
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The classic techniques (Hey Groves, Lindemann, Lange, etc) with preserved insertions of gracillis and/or semitendinosus give excellent results. Unfortunately, these surgical procedures are done through larger (sometimes multiple) incisions. That's why they are not so often used in favour of less invasive surgery with BTB.
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Does it tell that passive range of motion is checked by CPM? Or manually or something else?
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Dear Sougata
ROM means range of movement (movement is defined by reference to a plane and/or axis) and is used to measure the motion of a joint. CPM means a continuous passive motion and is exercised by an electrical device, widely used in postoperative orthopedic surgery of the knee and hip. The postoperative movements are started in the following day after the surgery and are very important because the joint movements stimulate muscle contraction and facilitate production of synovial fluid ( articular cartilage nutrition). CPM is regulated, according to need of each joint . The movement can be progressively increased in accordance with the needs.
In the orthopedic area there is a important phrase: "Life is movement and movement is life "
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During the anterior cruciate ligament reconstruction, my hanstring graft (STG) has fell on the floor accidently twice. I did not have option of the allograft. I only had the options of either harvesting the same side BTB or contralateral hamstring or using the same graft after cleansing it. I exercised the last option of washing the graft with 500 ml saline, soaking it in cidex for 30 minutes and again washing it with saline. I was fortunate enough that in both the patients there was no infection. Both the patients have completed 2 years and 5 years follow up and the KT assessment as well as functional assessment is good.
But is it the right way to go in this situation or we should always harvest another new graft?
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Dear Ravi
Below comments from Bernard R. Bach, MD, - What Do You Do If You Drop the Graft on the Floor? Healio Orthopedics.
Great care must be taken to avoid contamination during harvest and or preparation of the graft for anterior cruciate ligament (ACL) reconstruction. Our protocol emphasizes that the surgeon who harvests the graft personally walks the tissue to the back table to reduce the risk of dropping the graft. Handing off of a freshly harvested graft to other members of the surgical team for preparation simply increases the likelihood dropping the graft. With this protocol, the senior author has not dropped any grafts in over 20 years of practice, including more than 1700 knee ligament procedures. Careful attention must be paid during preparation on the back table as well. The fully prepared graft is placed in a marked kidney basin. All operative personnel are informed to prevent the graft from being inadvertently passed off the sterile field
When the graft is brought to the operative field for graft placement, if it is wrapped in a laparotomy sponge, theoretically the only contaminated portion would be the sutures extending beyond the sponge if the graft were dropped.
If the graft is dropped, the salvage falls into one of several possible categories, namely cleaning the graft, using an alternative graft (auto or allograft), or stopping the procedure and completing the surgery at another time with a different graft.
One study showed a 58% rate of positive culture when the graft was dropped and left on the operating room floor for 15 s. Molina et al have shown that a 90-s soak in chlorhexadine gluconate is the most effective method to resterilize the graft
Another report found that a 30-min soak in 4% chlorhexadine followed by a 30-min soak in triple antibiotic solution (gentamicin, clindamycin, polymixin), followed by sterile saline wash was 100% effective in sterilizing contaminated rabbit patellar tendon grafts. In that same study, 10% povidone-iodine was 100% ineffective, as was triple antibiotic soak used in isolation.
A survey of sports medicine specialists found that most would choose cleansing the graft to manage the problem of a dropped graft. Forty-three surveyed surgeons reported having cleansed a contaminated graft and none reported postoperative infections.3
Another option is choosing an alternative graft. This requires preoperative consent from the patient or intraoperative consent from a family member and may be problematic for a patient who expects one graft type but ends up with another. Some surgeons routinely consent their patients for the use of an allograft should the autograph become contaminated or otherwise compromised. Again, if this option is selected, preoperative discussion with the patient is best because cultural or religious beliefs may preclude the use of cadaveric tissue.
Our preference would be cleansing the graft using a 30-min soak in 4% chlorhexadine gluconate followed by lavage with sterile saline, then another 30-min soak in triple antibiotic solution (0.1% gentamicin, 0.1% clindamicin, 0.05% polymyxin) and another sterile saline wash. Washing the chlorhexadine is crucial because chlorhexadine-induced chondrolysis has been reported.4 While this protocol is time consuming, it has solid scientific backing and would allow one to proceed with the same graft as planned preoperatively. One could consider a course of postoperative antibiotics, although we would refrain from this as it would likely only mask an underlying infection, delaying its definitive treatment. In addition, we recommend full disclosure to the patient regarding the incident and the low likelihood of any residual difficulties.
References
1. Molina ME, Nonweiller DE, Evans JA, DeLee JC. Contaminated anterior cruciate ligament grafts: the efficacy of 3 sterilization agents. Arthroscopy. 2000;16:373-378.
2. Goebel ME, Drez D Jr, Heck SB, Stoma MK. Contaminated rabbit patellar tendon grafts: in vivo analysis of disinfecting methods. Am J Sports Med. 1994;22:387-391.
3. Izquierdo R Jr, Cadet ER, Bauer R, Stanwood W, Levine WN, Ahmad CS. A survey of sports medicine specialists investigating the preferred management of contaminated anterior cruciate ligament grafts. Arthroscopy. 2005;21:1348-1353.
4. Van Huyssteen AL, Bracey DJ. Chlorhexadine and chondrolysis in the knee. J Bone Joint Surg Br. 1999;81-B:995-996.
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Can the patient walk immediately putting weight on the limb? Should the patient use a knee brace articulated and how? Can the patient immediately articulate the knee? When may the patient resumes sport? etc ...
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My patients start full weight bearing with a brace immediately. The knee flexion and SLR (without brace) is started ASAP. They start light jogging at 3 months.
Sports specific training is started at 5-6 months depending upon the progress of individual patient.
They are back to sports at 7-8 months.
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Recently, a new randomized controlled clinical trial comparing partial menistectomy and sham surgery in patients without relevant osteoarthritis of the affected knee has been published (Sihvonen et al., NEJM 2013: http://www.nejm.org/doi/full/10.1056/NEJMoa1305189).
In summary, clinical outcome at 12 months in the "partial menistectomy" group was no better when compared to sham surgery, while significant improvement from baseline was found in both groups.
What is your interpretation of the results of this study ? What conclusion can be drawn by this study ? Do you think the study has significant limitations ? What do you consider the reason for improvement in the sham arm of the surgery ?
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With all respect to the authors of the study and the editorial board of the journal, we should be very cautious in interpreting the results of a single study that supports an idea or concept that is in contrast to the current clinical practice and our common sense. As we all know, there is despite the possibility of scientific fraud (which I would exclude in this case, but look at historic fake studies etc.) there is a lot of room for bias and error.
First of all, we do not know, how exactly the partial meniscectomy was performed (radical, little resection…, although described by the authors. Several surgeons might have different understandings of the same terms…). I do share the critizism, that there is no information about mechanical axis, joint load etc., patella problems… which probably would have been asked for in an orthopaedic journal…!
The number of patients n=146 is very small, especially for a multicentre study!
The fact, that the authors cannot find a difference between both groups, does not mean, that there isn’t one (type-II-error). This is a frequent misinterpretation in orthopaedic manuscripts.
I have calculated the power of the study results based on the means, standard deviations and sample size provided in Table 1 of the paper with the following results:
Power one-sided power two-sided
Lysholm knee score 0.05 0.05
WOMET score 0.33 0.28
Score for knee pain after exercise 0.22 0.15
Score for knee pain at rest 0.19 0.12
15D score 0.26 0.17
(G*Power Version 3.0.10, Franz Faul, University of Kiel, Germany. Post-hoc analysis, t-test, n1=n2, α-error 0.05)
A power of 0.8 or more usually is considered to be good. This was intended by the authors in an a priori power-analysis. They fail by far to meet an acceptable power of their analysis.
If I take the results for the scores with their SD and calculate an a priori sample estimation, the necessary number of patients in the study would have been: 336914, 381, 699, 965 and 567 in the same order of scores as above!
It is interesting, that the authors do not comment on this, although apparently statistical consultancy was given.
There are some other issues: the patients in both groups were overweight (mean).
A left meniscus lesion does something harmful with the knee: it causes swelling, does mechanically damage the cartilage, activate inflammation cascades and enzymes and cytokines… This is very difficult to measure and is not considered in the sham group. What do the authors think, happended to the torn meniscus?
After successful partial medial meniscectomy I would expect the patient to be in the following condition after one year postoperative: no limping, full weight-bearing, no giving way or locking, no pain, no swelling, no problem climbing stairs, no problem to perform squatting. This “perfect” patient would result in a Lysholm score of 100 points. Noticable pain during heavy exertion, swelling during heavy exertion, little problems climbing stairs and limitation of sqatting not more than 90 degrees would be a less favourable but acceptable result. This patient would still have a Lysholm score of 84 points! Both groups only reach 60 point one year after surgery / sham surgery! Why is that? There are probably other reasons than only the meniscus…
My greatest concern is the last sentence in the conclusion: “These results argue against the current practice of performing arthroscopic partial meniscectomy in patients with a degenerative meniscal tear.” This is not true. As explained above, the authors did not prove, that there is no difference between both groups but instead they were not able to show a difference. To transfer this into the clinical setting, the sentence would be: “These results argue against an attempt to stop performing arthroscopic partial meniscectomy in patients with a degenerative meniscal tear (because the uselessness or inability to show a benefit after one year of intervention could not be shown).” This is a complete different story.
The Editors of the NEJM should be aware of this. I don’t know, why they did not intervene…
This study probably started with good intentions. Now it probably will cause a lot of discussion and misinterpretation of the findings and in my personal opinion, will not help to treat our patients better.
My personal conclusion: although we all can be wrong with “gut feelings”, you can never beat common sense with statistics.
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Varisation osteotomy is an established treatment for younger patient with arthritis of knee due to valgus malalignment. Since the majority of those deformities is located on the femur, supracondylar varisation osteotomy is indicated in the majority of the cases. Nevertheless, in some case in tibial deformities osteotomy of the proximal tibia can be performed. Is there an indication for double osteotomies in patients with a mixed type (femoral and tibial) deformity?
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Dear Gustavo, by doing it in the way of your recommendation, you will probably be right in the majority in the cases, but you will certainly not perform your correction at the site of the deformity in those with a femoral varus or a tibial valgus deformity ... my questions actually yielded on those patients with a severe mixed type (combined femoral and tibial) deformity ... in order to avoid an oblique joint line double osteotomy certainly seems an interesting option
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Recently the Anterolateral ligament has been suggested as an important anatomical structure for rotational stability of the knee? What is your opinion on the relevance of this structure?
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Dear Philipp
Last month, knee surgeons from the University Hospitals Leuven in Belgium announced that they had found a new knee ligament (ALL - Anterolateral Ligament), one that had not previously been specifically identified despite untold numbers of past knee dissections and scans. This surprising announcement, in The Journal of Anatomy, should improve our understanding of how the knee works and why some knee surgeries disappoint and also underscores the continually astonishing complexity of human anatomy.
The orthopedic surgeons Dr. Steven Claes and Dr. Johann Bellemans and their colleagues gathered 41 knee joints from human cadavers and began minutely dissecting them.Positioned at the front of the knee, it would be vulnerable to tearing when an A.C.L. was injured; the same forces would move through both ligaments. In my opinion more studies are needed to determine the real importance of this ligament
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Functional assessment of patients undergoing ACL reconstruction: you use Cincinnati Knee Rating system, IKDC or SANE (single assessment numeric evaluation), or other?
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I do not know the SANE score in detail but I just had a look on the publication of which to probably refer to concerning the correlation coefficient. I also consider 0.66 is more a moderate correlation than a strong correlation and I agree with David that the purpose of your evaluation is probably important. SANE might be attractive when evaluating a huge cohort of patients .... If you are planning a scientific study including a reasonable amount of patients, I would definitely go with the more traditional scores ... what is also interesting in the SANE paper is, that the correlation in the ACL reconstruction subgroup was lower compared to the overall knee arthroscopy group ...
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Limited range of motion is frequently observed following intra- or periarticular fractures of the knee. What do you consider special about this entity in comparison to other types of arthrofibrosis? What are your criteria to indicate revision surgery and how do you address arthrofibrosis? What time point following fracture treatment is best to perform revision surgery?
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This is a very difficult question. The "simple" answer would be that arthrolysis is rarely indicated in the era of joint replacement surgery. But the context of the question is different. It is well known that exact and perfect reduction of intraarticular fractures of the knee is not always possible. Haemarthrosis, loose bone fragments, soft-tissue damage, malunion, etc. make the recovery of optimal ROM problematic. In any case early kinesitherapy should be initiated as soon as possible. Close follow of the development of joint mobility is advisable too. In my opinion revision surgery (incl. arthrolysis) should be decided individually from case to case.Of course, haemarthrosis should be treated early on emergency base.
In any case, fracture healing should be the primary goal. When the fracture heals and the ROM is unacceptable, then there is a vast range of options including arthrolysis, arthrodesis, and last but not least TKA.
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For a dynamic, ever changing human knee environment Is it more important to get the knee to feel right during surgery or more important to work on post-operative rehabilitation?
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Total Knee Replacement is a combination of proper and accurate bone cuts and proper and accurate soft tissue balance. This will help the proprioception, facilitate the rehabilitation and so improve the movement of the knee and the satisfaction of the patient. There is no question that soft tissues play a huge role to the success of the knee replacement
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Does anybody have the experience of observing cartilage regeneration by itself directly or indirectly (for example, by radiography)?
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Dear Shaw-Ruey Lyu, cartilage repair may occur spontaneously, but it depends on a lot of parameters as cause for cartilage lesion, size, depth, configuration, general health of the joint, systemic conditions, biomechanics etc. E.g. in case of osteochondral lesions the subchondral bone layer is opened and progenitor cells may invade the forming fibrin clot and finally differentiate into cartilage like tissue. This is a similar mechanism as it is supposed to occur after microfracturing. Stem cells may also invade from the synovia, but again success varys with the different influencing factors. Best regards, Hagen Schmal.
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Do you have a specific diagnostic algorithm? Please specify what to do and when. What kind of imaging modalities do you include?
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We published a paper (The painful knee after TKA: a diagnostic algorithm for failure analysis. KSSTA). There you find our algorithm. Hope this is helpful for you.