Causes
Most cases of CTS are idiopathic.[4] Many people with carpal tunnel syndrome have gradually increasing symptoms over time. A common factor in developing carpal tunnel symptoms is increased hand use or activity. While repetitive activities are often blamed for the development of CTS, the correlation is often unclear. Physiology and family history may have a significant role in individual's susceptibility.
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Work related
The relationship between work and CTS is controversial; in many locations workers injured at work are entitled to time off and compensation. Many cases of carpal tunnel syndrome are provoked by repetitive grasping and manipulating activities. The exposure can be cumulative. Symptoms are commonly exacerbated by forceful and repetitive use of the hand and wrists in industrial occupations, including jack hammer operators, meat packers, computer users and musicians. In the U.S., for instance, carpal tunnel syndrome is the biggest single contributing factor to lost time at work. Carpal tunnel syndrome results in billions of dollars of workers compensation claims every year.[citation needed]
However, recent studies and peer review articles have found no relationship between carpal tunnel syndrome and office-type work. Recently the Harvard Medical School published a report in which it addressed carpal tunnel syndrome. The Harvard report cited to the 2003 Journal of American Medical Association study[5] and the 2001 study in Neurology (the Mayo Clinic Study [6]) in reporting that computer use did not increase a person's risk of developing carpal tunnel syndrome.
Hyperthyroidism, osteoarthritis and diabetes were most often associated with CTS-like symptoms, as were variables such as age, obesity and wrist dimension. In a studies by SG Atcheson, only 35 of 297 subjects were aware of the underlying health condition which could account for their CTS like symptoms.[7],[8] Hence, these causes would be missed by doctors if they were relying on a patient's health history to rule out other causative factors. It is important that a doctor rule out other causes of CTS-like symptoms. If a patient does not have CTS, corrective surgery is destined to fail.
Studies have also related carpal tunnel and other upper extremity complaints with psychological and social factors. A large amount of psychological distress showed doubled risk of the report pain, while job demands, poor support from colleagues, and work dissatisfaction also showed an increase in the report of pain, even after short term exposure.[9]
On the other hand, in 1997, studies done by the National Institute for Occupational Safety and Health (NIOSH), indicated that job tasks involving highly repetitive manual acts or necessitating wrist bending or other stressful wrist postures were connected with incidents of CTS or related problems. However, it appears that the 30+ studies reviewed were concerned with the occupations of assembly line workers, meat packers, food processors, and the like, not general office work.
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Trauma related
* Fractures of one of the arm bones, particularly a Colles' fracture.
* Dislocation of one of the carpal bones of the wrist.
* Strong blunt trauma to the wrist or lower forearm, incurred for example by using arm extremity to cushion a fall or protecting oneself from falling heavy objects.
* Hematoma forming inside the wrist, because of internal hemorrhaging.
* Deformities due to abnormal healing of old bone fractures.
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Non-traumatic
Non-traumatic causes generally happen over a period of time, and are not triggered by one certain event. Many of these factors are manifestations of physiologic aging and should not be considered preventable. Examples include:
* Tenosynovitis, which is inflammation of the thin mucinous membrane around the tendons. Part of the process of inflammation is swelling, and this compresses the nerve. Swelling of this membrane is the final common pathway for most cases of carpal tunnel, whether caused idiopathically, through exposure, or medically.
* With pregnancy and hypothyroidism, fluid is retained in tissues, which swells the tenosynovium.
* Acromegaly, a disorder of growth hormones, compresses the nerve by the abnormal growth of bones around the hand and wrist.
* Tumours (usually benign), such as a ganglion or a lipoma, can protrude into the carpal tunnel, reducing the amount of space. This is exceedingly rare (less than 1%).
* Double crush syndrome, where there is compression or irritation of nerve branches contributing to the median nerve in the neck or anywhere above the wrist. This then increases the sensitivity of the nerve to compression in the wrist. This, while a possible factor, is also a rare contributor in most cases.
* Idiopathic causes, which no one can explain, can also cause this disease. This is very common.
* Common activities that have been identified as contributing to repetitive stress induced carpal tunnel syndrome include:
o Computer keyboarding or typing
o Playing video games or computer games
o Playing a musical instrument
o Any activity where hand use is vigorous and routine could contribute (surgeons, dentists). Still, these activities are often merely associated with, but do not actually cause, carpal tunnel syndrome.
Often people suffering from carpal tunnel syndrome can have multiple contributing factors which are aggravated by vigorous hand activities and repetitive stress trauma to the hand.
Proper attention to ergonomic considerations can reduce or eliminate these kinds of exposures.
While carpal tunnel syndrome is often called a "repetitive strain injury" (RSI) or "cumulative trauma disorder" (CTD), these labels are looked down on by medical doctors, particularly hand specialists. Carpal tunnel is a specific condition with specific typical symptoms that responds fairly reliably. Most of the time carpal tunnel is not caused by an "strain" or "trauma" of any type. RSI and CTD are relatively non-specific terms with non-specific symptoms that respond variably to treatment. Labelling someone with RSI or CTD can be unhealthy psychologically.
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Diagnosis
Clinical assessment by history taking and physical examination can usually diagnose carpal tunnel syndrome.
Phalen's maneuver is performed by flexing the wrist gently as far as possible, then holding this position and awaiting symptoms. A positive test is one that results in numbness in the median nerve distribution. The quicker the numbness starts, the more advanced the condition.
A classic, though less effective method, Tinel's sign, is a way to detect irritated nerves. It is performed by lightly tapping (percussing) over the nerve to elicit a sensation of tingling or "pins and needles" in the distribution of the nerve. Tinel's sign is sometimes referred to as "distal tingling on percussion" or DTP. Carpal compression test, or applying firm pressure in the palm over the nerve to elicit symptoms has been discussed as a valuable test.[10]
If, based on history and physical examination, carpal tunnel is suspected, then patients will likely be tested electrodiagnostically with nerve conduction studies or electromyography. These are objective measurements that look at the health of the nerve and can be correlated to the symptoms.
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Treatment and prevention
There has been much discussion as to the most effective treatment for CTS.[11] However, treatments can be generally divided into six basic categories:
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Reversible Causes
Some causes of carpal tunnel syndrome are amenable to medical therapy. Treatment of these conditions tends to reverse the symptoms of carpal tunnel syndrome. These causes include metabolic disorders such as hypothyroidism
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Immobilizing braces
A splint can keep the wrist straight.
Enlarge
A splint can keep the wrist straight.
The importance of wrist braces and splints in the carpal tunnel syndrome therapy is unknown for many people. In 1993, The American Academy of Neurology [12] recommend a non-invasive treatment for the CTS at the beginning (except for sensitive or motor deficit or grave report at EMG/ENG): a therapy using splints was indicated for light and moderate pathology. Then the “Clinical Guideline on Wrist Pain” from the American Academy of Orthopaedic Surgeons [13] recommends that patients with suspected carpal tunnel syndrome modify their activities for two to six weeks while they are treated with wrist splints and nonsteroidal antiinflammatory medication. If these therapies are ineffective, or if the patient has thenar muscle atrophy or weakness, the Guidelines recommend referral to specialist. The practice Guidelines of the American College of Occupational and Environmental Medicine [14] suggests a similar approach. In 2002 Katz JN and Simmons BP, about carpal tunnel syndrome say: “If carpal tunnel syndrome seems likely, conservative management with splinting should be initiated. If the condition fails to improve, we recommend referral to a specialist with expertise in the diagnosis and management of carpal tunnel syndrome” [15]. Many health professionals suggest that, for best results, one should wear them at night and, if possible, during the activity primarily causing stress on the wrists,[16] but they can be limiting and uncomfortable to wear.[17] The problems of limitation of movements (especially fingers) and discomfort have been improved with a new type of brace (Policarpal). This brace can be comfortably worn night and day because it does not have a splint and the fingers can move freely; it requires 15 days of use to be effective.
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Physiotherapy
Physiotherapy offers several ways to treat and control carpal tunnel syndrome. Manual treatment that includes deep friction massage can help manage the swelling that is a factor in nerve compression. This is combined with manual stretches to the tendons to the fingers and wrist. Another modality of treatment is ultrasonic therapy, which in some cases may work as a treatment by itself, but is better when used in combination with other physiotherapy treatments. There are numerous other techniques offered by competent occupational and physical therapists (O.T. or P.T.) that can aid in the control of carpal tunnel symptoms. Therapy can be very effective in helping to calm flares of carpal tunnel symptoms. The key is also to maintain the lessons learned in therapy in a home program. Therapy in this way can control symptoms. While therapy is useful for short or long term management of "mild to moderate" carpal tunnel symptoms, one must note that it controls the process, but does not cure it. Thus, if nothing else changes, and therapy is discontinued, then symptoms will usually ultimately return. Finally, physical therapy tends to be ineffective in even temporarily controlling symptoms of "moderate to severe" severity....
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Localized steroid injections
Steroid injections can be quite effective for temporary relief from symptoms of CTS for a short time frame while a patient develops a longterm strategy that fits with his/her lifestyle. In certain patients an injection may also be of diagnostic value. This treatment is not appropriate for extended periods, however. In general, medical professionals only prescribe to localized steroid injections until other treatment options can be identified. For most patients, permanent relief requires surgery.[18]
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Prioritizing hand activities and ergonomics
Any forceful and repetitive use of the hands and wrists can cause upper extremity pain. While avoiding activities that cause repetitive stress is an option that can help avoid the pain, it causes people to curtail their careers, forfeit earnings and give up whole segments of their lives. Our self esteem as human beings and contributors at home, at work and at recreation is directly tied to the way we use our hands. Giving up activity is a poor option for most people.
More frequent rest can be useful if it can be orchestrated into one's schedule, but rest is not very practical in today's active work and play environments. It has been shown that taking multiple mini breaks during the stressful activity is more effective than taking occasional long breaks. There are computer applications that aid users in taking breaks. All of these applications have recommended defaults, following the most effective average break configuration, which is a 30 sec. pause every 3 to 5 minutes (the more severe the pain, the more often one should take this break). Before investing in these types of programs, it's best to consult with a doctor and research whether computer use is causing or contributing to the symptoms, as well as getting a formal diagnosis.
More pro-active ways to reducing the stress on the wrists which will alleviate wrist pain and strain involve adopting a more ergonomic work and life environment such as using an ergonomic keyboard (and perhaps switching from a QWERTY key layout to a more efficient Dvorak Simplified Keyboard layout). Early studies claimed that ergonomic keyboards significantly reduced wrist stress; meta-analyses of these studies, however, report significant flaws in the research and question the usefulness of such keyboards.[19][20]
It is also important that ones body be aligned properly with the keyboard. This is most easily accomplished by bending ones elbows to a 90 degree angle and making sure the keyboard is at the same height as the elbows. Also it is important not to put physical stress on the wrists by hanging the wrist on the edge of a desk, or exposing the wrists to strong vibrations (e.g. manual lawn mowing). Position the computer monitor directly in front of your seat, so the neck is not twisted to either side when viewing the screen.
Exercises that relax and strengthen the muscles of the upper back can reduce the risk of a double crush of the median nerve. Spinal manipulations performed by an osteopath, physical therapist or chiropractor may be appropriate to relieve compression of the nerve.
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Medication and diet
Using an over-the-counter anti-inflammatory such as aspirin or ibuprofen or Naproxen can be effective as well for controlling symptoms. Pain relievers like Tylenol will only mask the pain, and only an anti-inflammatory will affect inflammation. Non steroidal inflammatory medications theoretically can treat the root swelling and thus the source of the problem. Oral steroids (prednisone) does the same but is generally not used for this purpose due to significant side effects. The most common complications associated with long-term use of anti-inflammatory medications are gastrointestinal irritation and bleeding. Also, some anti-inflammatory medication have been linked to heart complications. No one should rely on these type of medications for chronic long-term pain without a doctor's supervision.
A more aggressive pharmaceutical option is an injection of cortisone, to reduce swelling and nerve pressure within the carpal tunnel.
Dietary changes can provide the body with the necessary nutrients needed to repair nerves and help reduce inflammation. With this, pressure on the nerve may be reduced, allowing it to heal. No specific vitamin or nutrient has been shown to have a noticeable anti-inflammatory effect, but taking a diverse multivitamin may have a noticeable effect on reducing inflammation in the body. One could argue that diet and vitamins have a small effect on carpal tunnel syndrome, similar to placebo. Their effect would be expected to be negligible except in the most mild of cases.
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Carpal tunnel release surgery
When visiting a hand surgeon, the first step would be examination of the hands and a review of the symptoms. If a condition other than carpal tunnel syndrome is present, the doctor will suggest the appropriate treatment. If CTS is suspected, depending on the severity and the situation, (s)he will first prescribe non-operative treatment with splinting and anti-inflammatory drugs. A test conducted on the nerve will positively determine whether or not it is compressed and if carpal tunnel syndrome is indeed the diagnosis.
If all the symptoms go away with splinting and medication, then surgery will not be necessary. If not, then the "carpal tunnel release" surgery is recommended.[21] In general, milder cases can be controlled for months to years, but severe cases are unrelenting symptomatically and likely will come to surgical treatment.[22]
There are several variations of technique to perform carpal tunnel release surgery. Each surgeon has differences of preference based on their personal beliefs and experience. All techniques have several things in common.
* They all involve brief (10-15 minute) outpatient procedures.
* They all involve some type of incision(s) on your wrist and/or palm.
* They all involve dividing (cutting) the transverse carpal ligament.
* They all incur a relatively rapid recovery time (days to weeks depending on the activity and technique).
* They all leave a cosmetically insignificant scar in most cases.
The two major types of surgery are open and endoscopic. Most surgeons perform open surgery, which is widely considered to be the gold standard. However, many surgeons are now performing endoscopic techniques. Open surgery involves a small incision somewhere on the palm about an inch or two in length. Through this the ligament can be directly viewed and divided with relative safety. Endoscopic techniques involve one or two smaller incisions (less than half inch each) through which instrumentation is introduced including probes, knives and the scope to see what you are doing. The ligament is viewed through a "keyhole" in this way and can be divided with relative safety. There are perhaps a half dozen commercial systems available that surgeons can use to do the endoscopic surgery.
Much debate has existed in the medical community of which technique is best. Open surgery is arguably a bit safer as there is less likelihood of inadvertent damage to surrounding nerves and blood vessels. Endoscopic surgery very likely will result in a quicker early recovery. In other words, people will feel less sore and be able to be more active in the several (1-5) weeks after surgery with endoscopic techniques. Several studies have suggested that either technique leaves patients with similar results if examined after about six weeks.
If the decision to operate is made, the technique choice is between the patient and surgeon. Surgeons can do either or both techniques. The surgeon can tailor treatments to patients' specific needs. Surgery to correct carpal tunnel syndrome has a 90% or better success rate, especially using endoscopic surgery techniques.[23],[24],[25] In general, endoscopic techniques are as effective as traditional open carpal surgeries[26],[27], though the faster recovery time typically noted in endoscopic procedures may be offset by higher complication rates.[28],[29] Success is greatest in patients with the most typical symptoms. The most common cause of failure is incorrect diagnosis, and it should be noted that this surgery will only fix carpal tunnel syndrome, and will not relieve symptoms with alternate causes. Recurrence is rare, and apparent recurrence usually results from a misdiagnosis of another problem. Complications can occur, but serious ones are infrequent to rare.
Carpal tunnel surgery is usually performed by an orthopaedic or plastic surgeon; some neurosurgeons and general surgeons also perform the procedure.
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Long term recovery
The early signs of carpal tunnel syndrome should not be ignored. Early denial of carpal tunnel symptoms is a sure way to lead to progressive symptoms.
Most people who find relief of their carpal tunnel symptoms with conservative or surgical management find minimal residual or "nerve damage".[30] Long-term chronic carpal tunnel syndrome (typically seen in the elderly) can result in permanent "nerve damage", i.e. symptoms of numbness, muscle wasting and weakness.
While outcomes are generally good, certain factors can contribute to poorer results that have little to do with nerves, anatomy, or surgery type. One study showed that mental status parameters, alcohol use, and involvement of an attorney yield much poorer overall results of treatment.[31] This really demonstrates how one's mental state, attitude and outlook affect carpal tunnel syndrome and almost any other medical problem that has potential subjective components such as pain and disability status.
Many mild carpal tunnel syndrome sufferers either change their hand use pattern or posture at work or find a conservative, non-surgical treatment that allows them to return to full activity without hand numbness or pain, and without sleep disruption. Other people end up prioritizing their activities and possibly avoiding certain hand activities so that they can minimize pain and perform the essential tasks.
Changing jobs is also commonly done to avoid continued repetitive stress tasks. Others find success by adjusting their repetitive movements, the frequency with which they do the movements, and the amount of time they rest between periods of performing the movements.
In summary, one has the choice of controlling the symptoms with any of the non-surgical options listed, or correcting the condition with surgery.[32]
While recurrence after surgery is a possibility, true recurrences are uncommon to rare.[33] Non-CTS hand pain is commonly mistaken for recurrence. Such hand pain may have existed prior to the surgery, which is one reason it is very important to get a proper diagnosis.
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See also
* Ergonomics
* Peripheral neuropathy
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References
1. ^ Treaster DE, Burr D (2004). "Gender differences in prevalence of upper extremity musculoskeletal disorders". Ergonomics 47 (5): 495-526. PubMed.
2. ^ a b eMedicine EMERG/83
3. ^ Michelsen H, Posner MA (2002). "Medical history of carpal tunnel syndrome". Hand Clin 18 (2): 257-68. PubMed.
4. ^ Sternbach G (1999). "The carpal tunnel syndrome". J Emerg Med 17 (3): 519-23. PubMed.
5. ^ Hedge A (2003). "Computer use and risk of carpal tunnel syndrome". JAMA 290 (14): 1854; author reply 1854-5. PubMed.
6. ^ Stevens JC, Witt JC, Smith BE, Weaver AL (2001). "The frequency of carpal tunnel syndrome in computer users at a medical facility". Neurology 56 (11): 1568-70. PubMed.
7. ^ Atcheson SG, Ward JR, Lowe W (1998). "Concurrent medical disease in work-related carpal tunnel syndrome". Arch Intern Med 158 (14): 1506-12. PubMed.
8. ^ Atcheson SG (1999). "Carpal tunnel syndrome: is it work-related?". Hosp Pract (Minneap) 34 (3): 49-56; quiz 147. PubMed.
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13. ^ American Academy of Orthopaedic Surgeons (1996, Accessed april 10, 2002, at NGC). "Clinical Guideline on wrist pain. National Guideline clearinghouse".
14. ^ Harris JS (1998). "ed. Occupational Medicine Practice Guidelines: evaluation and management of common health problems and functional recovery in workers.". Beverly Farms, Mass.: OEM Press.
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16. ^ Premoselli S, Sioli P, Grossi A, Cerri C (2006). "Neutral wrist splinting in carpal tunnel syndrome: a 3- and 6-months clinical and neurophysiologic follow-up evaluation of night-only splint therapy". Eura Medicophys. PubMed.
17. ^ Michlovitz SL (2004). "Conservative interventions for carpal tunnel syndrome". J Orthop Sports Phys Ther 34 (10): 589-600. PubMed.
18. ^ Hui AC, Wong S, Leung CH, Tong P, Mok V, Poon D, Li-Tsang CW, Wong LK, Boet R (2005). "A randomized controlled trial of surgery vs steroid injection for carpal tunnel syndrome". Neurology 64 (12): 2074-8. PubMed.
19. ^ Lincoln A, Vernick J, Ogaitis S, Smith G, Mitchell C, Agnew J (2000). "Interventions for the primary prevention of work-related carpal tunnel syndrome.". Am J Prev Med 18 (4 Suppl): 37-50. PMID 10793280.
20. ^ Verhagen A, Karels C, Bierma-Zeinstra S, Burdorf L, Feleus A, Dahaghin S, de Vet H, Koes B (2006). "Ergonomic and physiotherapeutic interventions for treating work-related complaints of the arm, neck or shoulder in adults.". Cochrane Database Syst Rev 3: CD003471. PMID 16856010.
21. ^ Hui AC, Wong SM, Tang A, Mok V, Hung LK, Wong KS (2004). "Long-term outcome of carpal tunnel syndrome after conservative treatment". Int J Clin Pract 58 (4): 337-9. PubMed.
22. ^ Kouyoumdjian JA, Morita MP, Molina AF, Zanetta DM, Sato AK, Rocha CE, Fasanella CC (2003). "Long-term outcomes of symptomatic electrodiagnosed carpal tunnel syndrome". Arq Neuropsiquiatr 61 (2A): 194-8. PubMed.
23. ^ Schmelzer RE, Della Rocca GJ, Caplin DA (2006). "Endoscopic carpal tunnel release: a review of 753 cases in 486 patients". Plast Reconstr Surg 117 (1): 177-85. PubMed.
24. ^ Quaglietta P, Corriero G (2005). "Endoscopic carpal tunnel release surgery: retrospective study of 390 consecutive cases". Acta Neurochir Suppl 92: 41-5. PubMed.
25. ^ Park SH, Cho BH, Ryu KS, Cho BM, Oh SM, Park DS (2004). "Surgical outcome of endoscopic carpal tunnel release in 100 patients with carpal tunnel syndrome". Minim Invasive Neurosurg 47 (5): 261-5. PubMed.
26. ^ Scholten RJ, Gerritsen AA, Uitdehaag BM, van Geldere D, de Vet HC, Bouter LM (2004). "Surgical treatment options for carpal tunnel syndrome". Cochrane Database Syst Rev (4): CD003905. PubMed.
27. ^ McNally SA, Hales PF (2003). "Results of 1245 endoscopic carpal tunnel decompressions". Hand Surg 8 (1): 111-6. PubMed.
28. ^ Thoma A, Veltri K, Haines T, Duku E (2004). "A meta-analysis of randomized controlled trials comparing endoscopic and open carpal tunnel decompression". Plast Reconstr Surg 114 (5): 1137-46. PubMed.
29. ^ Chow JC, Hantes ME (2002). "Endoscopic carpal tunnel release: thirteen years' experience with the Chow technique". J Hand Surg [Am] 27 (6): 1011-8. PubMed.
30. ^ Olsen KM, Knudson DV (2001). "Change in strength and dexterity after open carpal tunnel release". Int J Sports Med 22 (4): 301-3. PubMed.
31. ^ Katz JN, Losina E, Amick BC 3rd, Fossel AH, Bessette L, Keller RB (2001). "Predictors of outcomes of carpal tunnel release". Arthritis Rheum 44 (5): 1184-93. PubMed.
32. ^ Gerritsen AA, de Vet HC, Scholten RJ, Bertelsmann FW, de Krom MC, Bouter LM (2002). "Splinting vs surgery in the treatment of carpal tunnel syndrome: a randomized controlled trial". JAMA 288 (10): 1245-51. PubMed.
33. ^ Ruch DS, Seal CN, Bliss MS, Smith BP (2002). "Carpal tunnel release: efficacy and recurrence rate after a limited incision release". J South Orthop Assoc 11 (3): 144-7. PubMed.
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answer #1
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answered by Anonymous
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