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Does anyone know how to stop metal knee from interfering with my gpx4500
Knee problems
- Thread starter Ray and Lips
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Gee whiz,thanks sounds very simplemadtuna said:
Hi and welcome
No idea mate but be prepared for some silly answers on here
Most are out of work stand up comedians :lol: :lol: :lol:
But yhey are a great bunch anyway
No idea mate but be prepared for some silly answers on here
Most are out of work stand up comedians :lol: :lol: :lol:
But yhey are a great bunch anyway
See i told you so :lol: :lol: :lol:
change metal detectors :lol:
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Sounds like joining was a waste of time,it is a genuine problem I was expecting a genuine answer thanks very much for your valuable time
malri_au
Steve
Mumetal shielding.
Dont take it to heart mateRay and Lips said:
i am sure you have a lot of minds thinking of was or ideas that will help you just chill out a bit
Ray and Lips...Firstly, welcome to the forum.I understand your frustration...but please don't take it to heart. Your question was a valid one and deserves a much more considered answer! :Y: It is one of those ...difficult ones to answer...but I think your solution lays in the wearing of some sought of 'knee guard'.A set of knee guards of good quality, modified with perhaps a complete rubber facing seems to me to be what your looking for. 
You may well have to do some trial and error with them...but I would be very surprised if the solution you seek is not satisfied by something in the order of what I suggest.
There are those here who take delight in having a joke.. usually without considering the feelings of those who bear the brunt of that 'joke'...and the rarity of your problem makes you an easy target for flippant remarks.
You will find however that your question will spark some debate amongst certain members and your problem will be solved.Good luck with it...try out as I suggested and please don't give up on us.
Kindest regards to you...reefer...aka... Rossco.
You may well have to do some trial and error with them...but I would be very surprised if the solution you seek is not satisfied by something in the order of what I suggest.
There are those here who take delight in having a joke.. usually without considering the feelings of those who bear the brunt of that 'joke'...and the rarity of your problem makes you an easy target for flippant remarks.
You will find however that your question will spark some debate amongst certain members and your problem will be solved.Good luck with it...try out as I suggested and please don't give up on us.
Kindest regards to you...reefer...aka... Rossco.
madtuna
Only owns one toaster
Mate I appologize if my answer upset you, though sorry I wont appologize for saying it as it was meant as a bit of harmless humour. Some get it, some don't unfortunately and I would have said it no matter who posed the question.
My serious answer I was about to post is that the only way is to maybe get a longer shaft or keep the knee as far away as possible from the coil or get a smaller coil.
No amount of shielding will help as far as I know.
My serious answer I was about to post is that the only way is to maybe get a longer shaft or keep the knee as far away as possible from the coil or get a smaller coil.
No amount of shielding will help as far as I know.
malri_au
Steve
Flowerpot said:
you betcha it is.
they use it in hard drives and other EMI situations.
it's costly stuff but,and you'd need to design something as it's not been done?
the other suggestion is valid too,I read of someone else with a metal hip sold their gpz7000,and went with a less sensitive detector.
silver
silver
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All I can think of is along madtuna's train of thought..... now in order to keep the knee completely out of the picture you will undoubtedly have to incur some degree of discomfort, but totally worthwhile in the long run.... you'll need to learn to detect from now on whilst in the prone position (Problem solved) :Y
mt's idea has its merits.... but
he's thinking more upright I believe
:
this could work for you
but to effect mobility mt's way would require this
there are several other options available to you inbetween both methods... but i doubt they'd do you much good
even getting a friend to help may not lend itself to efficiency
nope.... I'm afraid it's gunna all get down to proneness.... that's gotta be your best bet at keepin that metal knee the absolute furtherest from your coil.... but don't get it mixed up with supine at all as that would just be a joke n leave you the laughing stock of the bush... mate
mt's idea has its merits.... but
he's thinking more upright I believe
this could work for you
but to effect mobility mt's way would require this
there are several other options available to you inbetween both methods... but i doubt they'd do you much good
even getting a friend to help may not lend itself to efficiency
nope.... I'm afraid it's gunna all get down to proneness.... that's gotta be your best bet at keepin that metal knee the absolute furtherest from your coil.... but don't get it mixed up with supine at all as that would just be a joke n leave you the laughing stock of the bush... mate
Hi R&L
Welcome to the forum. Like others, we have our share of lunatics here.
I have a titanium left knee and swing a 4500.
There is NO way to shield the metal from interacting with the machine's magnetic pulses.
Luckily I'm right handed, and I have learned to keep the coil away from it.
I swing to the right when stepping forward with my left leg and vice versa.
Larger coils such as the 17*13 Evo are a little problematic, but smaller coils such as the 14*9 Evo and 11" Commander are no problem with slightly longer shafts.
I also know the sound of its interaction with my knee, so I know when to ignore it.
I have tried using a GPZ. It is harder to operate with the knee than the 4500 - but still possible - just need to keep the coil to the right.
I am now used to it, and still detect on the goldfields as well as ever.
Keep at it.
Welcome to the forum. Like others, we have our share of lunatics here.
I have a titanium left knee and swing a 4500.
There is NO way to shield the metal from interacting with the machine's magnetic pulses.
Luckily I'm right handed, and I have learned to keep the coil away from it.
I swing to the right when stepping forward with my left leg and vice versa.
Larger coils such as the 17*13 Evo are a little problematic, but smaller coils such as the 14*9 Evo and 11" Commander are no problem with slightly longer shafts.
I also know the sound of its interaction with my knee, so I know when to ignore it.
I have tried using a GPZ. It is harder to operate with the knee than the 4500 - but still possible - just need to keep the coil to the right.
I am now used to it, and still detect on the goldfields as well as ever.
Keep at it.
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Thank you all for your replies. Just turned 70,working 65 hours a week. 1 day off in 20 ,work with comedians all day,have body parts removed and replaced,trying to fund a 20 year dream, sometimes I do get a little testy, my apologies regards Ray.
I must try some of those poses Silver, after I update my health insurance :lol: :lol: :lol:
Mackka
Mackka
You can get longer bottom shafts that may help regards john :Y:
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Hi ,
I found this article on metal sensitivity and knee replacements you may not be sensitive but your knee is on the detector . Depends how far you want to go . Sorry but I'm a registered nurse and could not help but put a clinical spin into this conversation .
Basic Science and Metal Sensitivity
All metals that come into contact with biologic systems undergo some degree of corrosion, and metal ions released from TKA components intra-articularly may form complexes with native proteins. These metal-protein complexes may act as antigens or allergens and cause an immunologic response in the body or synovial joint. The most common metal sensitizer in humans is nickel, followed by cobalt and chromium.4,5 Polyethylene and polymethyl methacrylate particles are relatively large and do not elicit the same response as metal ions.4,5
The prevalence of metal sensitivity in the general population is approximately 10% to 15%. Nickel sensitivity has the highest prevalence, approximately 14%, and cross-reactivity between nickel and cobalt is most common.5 However, the prevalence of metal sensitivity in patients with well-functioning implants, mostly of the hip, is approximately 25%.5 In a review of studies of patients with a failed, loose, or poorly functioning implant, the average prevalence of metal sensitivity was 60% (range, 13% to 71%).5 It is not known whether this phenomenon is a cause or an effect.
The pathophysiology of metal hypersensitivity to orthopaedic implants has been described previously in great detail.5 This implant-related hypersensitivity is generally a type IV allergic reaction, a delayed cell-mediated response, with activation of specific T lymphocytes. These and other lymphocyte populations release a variety of cytokines that perpetuate the inflammatory response and trigger the participation of activated macrophages.5 This response can produce substantial tissue inflammation and eventual periprosthetic tissue damage. Although it is known that Langerhans cells in the dermis are associated with skin hypersensitivity reactions, the particular cells in the periprosthetic knee joint responsible for the presentation of the metal-protein antigen are not known but could be endothelial cells, macrophages, or other synovial tissue cells.5
No generally accepted and reliable test is available for the clinical diagnosis of metal hypersensitivity to the components used in total hip arthroplasty or TKA.5 Dermatologists routinely have used a panel of cutaneous patch testing to different metal-salt complexes to determine hypersensitivity to a particular metal (Figure 1). An erythematous reaction to the allergen can be rated only qualitatively. However, controversy exists over the validity of patch testing to determine deep-tissue or joint hypersensitivity to metals.5 In a retrospective, case-controlled study of the sensitivity to metals in TKA components, Granchi et al6 reported on 94 patients who underwent dermal (back) patch testing to 11 metals and haptens for bone cements. In 20 patients who had no knee implant but who were candidates for TKA, 15% had positive patch testing to at least one metal hapten. Positive patch testing was significantly greater in a group of 27 patients with a stable knee arthroplasty (44%; P = 0.05) and in a group of 47 patients with a loose knee arthroplasty (57%; P = 0.001). No predictive value of the patch testing was seen in determining the fixation status of the TKA.6 The medical history for metal allergy identified by previous skin testing or a questionnaire was found to be a risk factor for the loosening of a TKA because failure was four times more likely in patients with prior symptoms of metal hypersensitivity.6
Figure 1
Figure 1
Clinical photograph demonstrating cutaneous patch testing on the upper back of a female patient who has persistent pain, synovitis, and stiffness after a total knee arthroplasty with an implant of a cobalt-chromium alloy. A mild allergic reaction to nickel, ...
Another test for metal hypersensitivity is the in vitro lymphocyte transformation test, in which peripheral blood lymphocytes from the patient are challenged with a variety of metal salts and the uptake of a radioactive nucleotide is quantified after 6 days.5 The final test is the in vitro leukocyte migration inhibition test, which quantifies the migration of cells in the presence of a sensitizing metal antigen by one of four methods.4,5 Few data show the utility of these in vitro tests for TKA patients, however. In a prospective study of 92 patients undergoing TKA in Japan, a modified lymphocyte stimulation test (mLST) was performed preoperatively, and 24 patients (26%) had a positive mLST response to at least one tested metal.7 The most frequent sensitizer was nickel, followed by chromium, cobalt, and iron.7 The clinical significance of these findings is unknown. At the present time, no evidence supports the routine or widespread preoperative patch or in vitro lymphocyte testing of patients for metal hypersensitivity before primary TKA.
I found this article on metal sensitivity and knee replacements
you may not be sensitive but your knee is on the detector . Depends how far you want to go . Sorry but I'm a registered nurse and could not help but put a clinical spin into this conversation . Basic Science and Metal Sensitivity
All metals that come into contact with biologic systems undergo some degree of corrosion, and metal ions released from TKA components intra-articularly may form complexes with native proteins. These metal-protein complexes may act as antigens or allergens and cause an immunologic response in the body or synovial joint. The most common metal sensitizer in humans is nickel, followed by cobalt and chromium.4,5 Polyethylene and polymethyl methacrylate particles are relatively large and do not elicit the same response as metal ions.4,5
The prevalence of metal sensitivity in the general population is approximately 10% to 15%. Nickel sensitivity has the highest prevalence, approximately 14%, and cross-reactivity between nickel and cobalt is most common.5 However, the prevalence of metal sensitivity in patients with well-functioning implants, mostly of the hip, is approximately 25%.5 In a review of studies of patients with a failed, loose, or poorly functioning implant, the average prevalence of metal sensitivity was 60% (range, 13% to 71%).5 It is not known whether this phenomenon is a cause or an effect.
The pathophysiology of metal hypersensitivity to orthopaedic implants has been described previously in great detail.5 This implant-related hypersensitivity is generally a type IV allergic reaction, a delayed cell-mediated response, with activation of specific T lymphocytes. These and other lymphocyte populations release a variety of cytokines that perpetuate the inflammatory response and trigger the participation of activated macrophages.5 This response can produce substantial tissue inflammation and eventual periprosthetic tissue damage. Although it is known that Langerhans cells in the dermis are associated with skin hypersensitivity reactions, the particular cells in the periprosthetic knee joint responsible for the presentation of the metal-protein antigen are not known but could be endothelial cells, macrophages, or other synovial tissue cells.5
No generally accepted and reliable test is available for the clinical diagnosis of metal hypersensitivity to the components used in total hip arthroplasty or TKA.5 Dermatologists routinely have used a panel of cutaneous patch testing to different metal-salt complexes to determine hypersensitivity to a particular metal (Figure 1). An erythematous reaction to the allergen can be rated only qualitatively. However, controversy exists over the validity of patch testing to determine deep-tissue or joint hypersensitivity to metals.5 In a retrospective, case-controlled study of the sensitivity to metals in TKA components, Granchi et al6 reported on 94 patients who underwent dermal (back) patch testing to 11 metals and haptens for bone cements. In 20 patients who had no knee implant but who were candidates for TKA, 15% had positive patch testing to at least one metal hapten. Positive patch testing was significantly greater in a group of 27 patients with a stable knee arthroplasty (44%; P = 0.05) and in a group of 47 patients with a loose knee arthroplasty (57%; P = 0.001). No predictive value of the patch testing was seen in determining the fixation status of the TKA.6 The medical history for metal allergy identified by previous skin testing or a questionnaire was found to be a risk factor for the loosening of a TKA because failure was four times more likely in patients with prior symptoms of metal hypersensitivity.6
Figure 1
Figure 1
Clinical photograph demonstrating cutaneous patch testing on the upper back of a female patient who has persistent pain, synovitis, and stiffness after a total knee arthroplasty with an implant of a cobalt-chromium alloy. A mild allergic reaction to nickel, ...
Another test for metal hypersensitivity is the in vitro lymphocyte transformation test, in which peripheral blood lymphocytes from the patient are challenged with a variety of metal salts and the uptake of a radioactive nucleotide is quantified after 6 days.5 The final test is the in vitro leukocyte migration inhibition test, which quantifies the migration of cells in the presence of a sensitizing metal antigen by one of four methods.4,5 Few data show the utility of these in vitro tests for TKA patients, however. In a prospective study of 92 patients undergoing TKA in Japan, a modified lymphocyte stimulation test (mLST) was performed preoperatively, and 24 patients (26%) had a positive mLST response to at least one tested metal.7 The most frequent sensitizer was nickel, followed by chromium, cobalt, and iron.7 The clinical significance of these findings is unknown. At the present time, no evidence supports the routine or widespread preoperative patch or in vitro lymphocyte testing of patients for metal hypersensitivity before primary TKA.
