Ottawa Knee Rules: Difference between revisions

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'''Project Edits - '''[[User:Heather Paulis|Heather Paulis]] , [[User:Michael Conaway|Michael Conaway]], [[User:Erika Van Horebeek|Erika Van Horebeek]] as part of the [[Vrije Universiteit Brussel Evidence-based Practice Project]]  
'''Project Edits - '''[[User:Heather Paulis|Heather Paulis]] , [[User:Michael Conaway|Michael Conaway]], [[User:Erika Van Horebeek|Erika Van Horebeek]] as part of the [[Vrije Universiteit Brussel Evidence-based Practice Project]]  


'''Top Contributors''' - {{Special:Contributors/{{FULLPAGENAME}}}}  
'''Top Contributors''' - {{Special:Contributors/{{FULLPAGENAME}}}}  
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== Purpose  ==
== Purpose  ==


A clinic decision rule to help determine need for x-rays or rule out fractures of the knee after acute injury.&nbsp;&nbsp;
A clinical decision rule to help determine the need for x-rays or to rule-out fractures of the knee after acute injury.  


== Objective  ==
== Objective  ==


The Ottawa knee rule is a descion rule used to determine the need for radiogrpahs in acute knee injuries. It was created because of the need for a rapid and good way to avoid unnecessary radiography.  
The Ottawa Knee Rules are decision rules used to determine the need for radiographs in acute knee injuries. It was developed because of the need for a rapid and accurate way to avoid unnecessary imaging.  


"Plain radiographs of the knee are among the most commonly ordered radiographs in U.S. emergency departments; 60% to 80% of patients with knee pain have a knee film at an estimated annual cost of $1 billion."<ref>Jackson JL, O'Malley PG, Kroenke, K. Evaluation of acute knee pain in primary care. Ann Intern Med. 2003 Oct 7;139(7):575-88. Review.</ref>92% will not have a fracture.<ref name="Stiel et al">Stiel I, Wells G, Hoag R, Sivilotti M, Cacciotti T, Verbeek R, Greenway K, McDowell I, Cwinn A, Greenberg G, Nichol G, Michael J. Implementation of the Ottawa knee rule for the use of radiography in acute knee injuries. JAMA; 1997; 278: 2075 - 2079</ref>  
"Plain radiographs of the knee are among the most commonly ordered radiographs in U.S. emergency departments; 60% to 80% of patients with knee pain have a knee film at an estimated annual cost of $1 billion."<ref>Jackson JL, O'Malley PG, Kroenke, K. Evaluation of acute knee pain in primary care. Ann Intern Med. 2003 Oct 7;139(7):575-88. Review.</ref>&nbsp;92% will not have a fracture.<ref name="Stiel et al">Stiel I, Wells G, Hoag R, Sivilotti M, Cacciotti T, Verbeek R, Greenway K, McDowell I, Cwinn A, Greenberg G, Nichol G, Michael J. Implementation of the Ottawa knee rule for the use of radiography in acute knee injuries. JAMA; 1997; 278: 2075 - 2079</ref>  


An estimated 1.3 million patients are seen annually in US emergency departments with acute knee trauma.&nbsp;<ref name="McCaig et al">McCaig LF. national Hospital Ambulatory Medial Care Survey: 1992 emergency department summary. Advance Data. 1994;245:1-12.</ref> <ref name="National Center">National Center for Health Statistics. National Hospital AmbulatoryMedical Care Survey 1992. Hyattsville, MD:National Center for Health Statistics; 1994.</ref>. Although only 6% of these patients have suffered a fracture, the vast majority undergo plain radiography of the knee. <ref name="National Center" /><ref name="Stiell IG">Stiell IG, Wells GA, McDowell I, et al. Use of Radiography in acute knee injuries: need for clinical decision rules. Acad Emerg Med. 1995;2:966-973.</ref><ref name="Gratton et al">Gratton MC, Salomone JA III, Watson WA. Clinically Significant radiograph misinterpretationsat an emergency medicine residency program. Ann Emerg Med. 1990;19:497-502.</ref><ref name="Mcconnochie">McConnochie KM, Roghmann KJ, Pasternack J, Monroe DJ, Monaco LP. Prediction rules for selective radiographic assessment of extremity injuriesin children and adolescents. Pediatrics. 1990;86:45-57.</ref>. More than 92% of these radiographic results are negative for fractures and exemplify the many low cost, but high volume tests that add to health care costs. <ref name="Moloney et al">Moloney TW, Rogers DE. Medical Technology: a different viewof the contentious debate over costs. N Eng J Med. 1979;301:1413-1419.</ref><ref name="Angell">Angell M. Cost containment and the physician. JAMA. 1985;254:1203-1207.</ref>. The Ottawa knee decision rule was developed in an attempt to allow physicians to be more selective with radiography, without missing clinically important fractures<ref name="Stiell and Greenberg">Stiell IG, Greenberg GH, Wells GA, et al. Derivation of a decision rule for the use of radiography in acute knee injuries. Ann Emerg Med. 1995;26:405-413.</ref>. A prospective study by Stiell, et al<ref name="Steill">Stiell IG, McKnight RD, Greenberg GH, McDowell I, Nair RC, Wells GA, Johns C, Worthington JR. Implementation of the Ottawa Ankle Rules. Journal of the American Medical Association 1994; 271:827-832.</ref>&nbsp;found the rules to be 100% sensitive for identifying fractures of the knee with the potential relative reduction in the use of radiography to be estimated at 28%. <br>  
An estimated 1.3 million patients are seen annually in US emergency departments due to acute knee trauma.<ref name="McCaig et al">McCaig LF. national Hospital Ambulatory Medial Care Survey: 1992 emergency department summary. Advance Data. 1994;245:1-12.</ref><ref name="National Center">National Center for Health Statistics. National Hospital Ambulatory Medical Care Survey 1992. Hyattsville, MD:National Center for Health Statistics; 1994.</ref>&nbsp;Although only 6% of these patients have sustained a fracture, the vast majority undergo plain radiography of the knee.<ref name="National Center" /><ref name="Stiell IG">Stiell IG, Wells GA, McDowell I, et al. Use of Radiography in acute knee injuries: need for clinical decision rules. Acad Emerg Med. 1995;2:966-973.</ref><ref name="Gratton et al">Gratton MC, Salomone JA III, Watson WA. Clinically Significant radiograph misinterpretations at an emergency medicine residency program. Ann Emerg Med. 1990;19:497-502.</ref><ref name="Mcconnochie">McConnochie KM, Roghmann KJ, Pasternack J, Monroe DJ, Monaco LP. Prediction rules for selective radiographic assessment of extremity injuries in children and adolescents. Pediatrics. 1990;86:45-57.</ref>&nbsp;More than 92% of these radiographic results are negative for fractures and exemplify the many low cost, but high volume tests, that add to health care costs.<ref name="Moloney et al">Moloney TW, Rogers DE. Medical Technology: a different view of the contentious debate over costs. N Eng J Med. 1979;301:1413-1419.</ref><ref name="Angell">Angell M. Cost containment and the physician. JAMA. 1985;254:1203-1207.</ref>The Ottawa Knee Rules were developed in an attempt to allow physicians to be more selective with radiography, without missing fractures.<ref name="Stiell and Greenberg">Stiell IG, Greenberg GH, Wells GA, et al. Derivation of a decision rule for the use of radiography in acute knee injuries. Ann Emerg Med. 1995;26:405-413.</ref>  
 
A prospective study by Stiell et al found the rules to be 100% sensitive for identifying fractures of the knee with the potential relative reduction in the use of radiography to be estimated at 28%.<ref name="Steill">Stiell IG, McKnight RD, Greenberg GH, McDowell I, Nair RC, Wells GA, Johns C, Worthington JR. Implementation of the Ottawa Ankle Rules. Journal of the American Medical Association 1994; 271:827-832.</ref>  


== Intended Population<br>  ==
== Intended Population<br>  ==


'''Ottawa knee rule in adults '''  
'''Ottawa Knee Rules in Adults '''  


There have been several studies in which they examined the effectiveness of the Ottawa knee rule. Each time, the studies gave the same results, namely the Ottawa knee rule led to a decrease in the use of knee radiography with patients with acute knee injury. This rule was also associated with a reduction of waiting times and costs. A worldwide use of this rule would be very important to decrease the health care costs without neglect of the patients.&nbsp;<ref name="Stiel et al">Stiel I, Wells G, Hoag R, Sivilotti M, Cacciotti T, Verbeek R, Greenway K, McDowell I, Cwinn A, Greenberg G, Nichol G, Michael J. Implementation of the Ottawa knee rule for the use of radiography in acute knee injuries. JAMA; 1997; 278: 2075 - 2079</ref>&nbsp;<ref name="Emparanza et al">Emparanza J, Aginaga J. Validation of the Ottawa knee rules. Annals of emergency medicine; 2001; 38: 364 - 368</ref>  
Several studies have examined the effectiveness of the Ottawa Knee Rules, with each reporting the Rules leading to a decrease in the use of knee radiography. The Rules were also associated with a reduction in waiting times and costs. Application of the Ottawa Knee Rules worldwide would be very important an advantageous in decreasing health care costs without risking the quality of patient care.<ref name="Stiel et al">Stiel I, Wells G, Hoag R, Sivilotti M, Cacciotti T, Verbeek R, Greenway K, McDowell I, Cwinn A, Greenberg G, Nichol G, Michael J. Implementation of the Ottawa knee rule for the use of radiography in acute knee injuries. JAMA; 1997; 278: 2075 - 2079</ref><ref name="Emparanza et al">Emparanza J, Aginaga J. Validation of the Ottawa knee rules. Annals of emergency medicine; 2001; 38: 364 - 368</ref>  


'''Ottawa knee rule in children '''  
'''Ottawa Knee Rules in Children '''  


On the use of the Ottawa knee rule in children, there is much doubt. In the past, there have been several studies which have been performed but all those studies had different results each time. There are studies showing that the use of the Ottawa knee rule in children is efficiently&nbsp;<ref name="Bulloch et al">Bulloch B, Neto G, Plint A, Lim R, Lidman P, Reed M, Nijssen-Jordan C, Tenenbein M, Klassen T. Validation of the ottawa knee rule in children: a multicenter study. Annals of Emergency Medicine; 2003; 42: 48 – 55</ref> but there are also studies that say the opposite. Therefore it is safer that the Ottawa knee rule is currently not used in children <ref name="Khine et al">Khine H, Dorfman D, Avner J. Applicability of Ottawa knee rule for knee injury in children. Pediatric emergency care; 2001: 17 (6): 401 - 404</ref>  
With regards to applying the Rules in children, the evidence is conflicting. In the past, several studies have been performed but all have reported varying results. Some have shown the use of the Ottawa Knee Rules in children as being accurate and efficient,<ref name="Bulloch et al">Bulloch B, Neto G, Plint A, Lim R, Lidman P, Reed M, Nijssen-Jordan C, Tenenbein M, Klassen T. Validation of the ottawa knee rule in children: a multicenter study. Annals of Emergency Medicine; 2003; 42: 48 – 55</ref> but many have reported the opposite as being true. Therefore, it is safer that the Ottawa Knee Rules be not used in children under the age of 18.<ref name="Khine et al">Khine H, Dorfman D, Avner J. Applicability of Ottawa knee rule for knee injury in children. Pediatric emergency care; 2001: 17 (6): 401 - 404</ref>  


It is important that there are more and clearer studies have to be done to investigate the effectiveness of this rule. Only when these have similar results, there could be made a clear and general conclusion. Until then, the conclusion is that an age under 18 years has been considered as exclusion criteria.<br>  
As such, there is an important need for more concise studies to investigate the effectiveness of the Rules in children. Only when the results become consistent should a clear and general conclusion be made. Until then, the consensus is that under the age of 18 years is considered an exclusion criteria.<br>  


== Criteria  ==
== Criteria  ==


If one of the following&nbsp;is present, radiographs are indicated<ref name="Steill" />:&nbsp;
If one of the following is present, radiographs are indicated:<ref name="Steill" />


#Age&gt;55 years  
#Age &gt;55 years  
#Islolated patellar tenderness without other bone tenderness  
#Islolated patellar tenderness without other bone tenderness  
#Tenderness of the fibular head  
#Tenderness of the fibular head  
#Inability to flex to 90°  
#Inability to flex the knee to 90°  
#Inability to bear weight immediately after injury and in the emergency department (4 steps) regardless of limping.<br>
#Inability to bear weight immediately after injury and in the emergency department (4 steps) regardless of limping<br>


[[Image:Ottawa-Knee.jpg|center|Areas of interest when palpating for the Ottawa Knee Rules]]  
[[Image:Ottawa-Knee.jpg|center|Areas of interest when palpating for the Ottawa Knee Rules]]  


If any of the following findings are present, the Ottawa knee rule may be contraindicated:&nbsp;<ref name="Glynn et al">Glynn P, Weisbach C. Clinical prediction rules: a physical therapy reference manual. Jones Barlett Learning; 2009: 248 pag (43 – 36)</ref>  
If any of the following are present, the Ottawa Knee Rules may be contraindicated:<ref name="Glynn et al">Glynn P, Weisbach C. Clinical prediction rules: a physical therapy reference manual. Jones Barlett Learning; 2009: 248 pag (43 – 36)</ref>  


#younger then 18 year  
#younger then 18 year  
#injuries greater then 7 days old  
#injuries greater then 7 days old  
#3re-evaluation of recent injuries  
#re-evaluation of recent injuries  
#altered levels of consciousness  
#altered levels of consciousness  
#paraplegia (an impairment in motor or sensory function of the lower extremities)
#paraplegia (an impairment in motor or sensory function) of the lower extremities
#multiple injuries or other fractures  
#multiple injuries or other fractures  
#pregnancy  
#pregnancy  
#isolated injuries of the skin without underlaying soft tissue or bone involvement:  
#isolated injuries of the skin without underlying soft tissue or bone involvement:  
#a. superficial lacertations or skin injuries  
**superficial lacerations or skin injuries  
#b. abrasions  
**abrasions  
#c. puntcure wounds  
**puncture wounds  
#d. burns  
**burns  
#referred from outside the hopsital with radiographs
#referred from outside the hospital with radiographs


== How to perform the examination ==
== How to Perform the Examination ==


When the Ottawa Knee Rule is executed the following things will be done: <ref name="Glynn et al">Glynn P, Weisbach C. Clinical prediction rules: a physical therapy reference manual. Jones &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp; Barlett Learning; 2009: 248 pag (43 – 36)</ref>  
When the Ottawa Knee Rule is executed the following things will be done: <ref name="Glynn et al">Glynn P, Weisbach C. Clinical prediction rules: a physical therapy reference manual. Jones &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp; Barlett Learning; 2009: 248 pag (43 – 36)</ref>  


#Check for sensitivity of the proximal fibula  
#Check for sensitivity of the proximal fibula  
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<br>  
<br>  


[[Category:Knee]] [[Category:Musculoskeletal/Orthopaedics|Orthopaedics]][[Category:Knee_Examination]]
[[Category:Knee]] [[Category:Musculoskeletal/Orthopaedics|Orthopaedics]] [[Category:Knee_Examination]]

Revision as of 19:12, 20 May 2016

Original Editor - Stacy Callow

Project Edits - Heather Paulis , Michael Conaway, Erika Van Horebeek as part of the Vrije Universiteit Brussel Evidence-based Practice Project

Top Contributors - Van Horebeek Erika, Admin, Stacy Callow, Evan Thomas, Claire Knott, Heather Paulis, Kim Jackson, Johnathan Fahrner, 127.0.0.1, Rachael Lowe, Selena Horner, Mariam Hashem, Kai A. Sigel and WikiSysop

Purpose[edit | edit source]

A clinical decision rule to help determine the need for x-rays or to rule-out fractures of the knee after acute injury.

Objective[edit | edit source]

The Ottawa Knee Rules are decision rules used to determine the need for radiographs in acute knee injuries. It was developed because of the need for a rapid and accurate way to avoid unnecessary imaging.

"Plain radiographs of the knee are among the most commonly ordered radiographs in U.S. emergency departments; 60% to 80% of patients with knee pain have a knee film at an estimated annual cost of $1 billion."[1] 92% will not have a fracture.[2]

An estimated 1.3 million patients are seen annually in US emergency departments due to acute knee trauma.[3][4] Although only 6% of these patients have sustained a fracture, the vast majority undergo plain radiography of the knee.[4][5][6][7] More than 92% of these radiographic results are negative for fractures and exemplify the many low cost, but high volume tests, that add to health care costs.[8][9]The Ottawa Knee Rules were developed in an attempt to allow physicians to be more selective with radiography, without missing fractures.[10]

A prospective study by Stiell et al found the rules to be 100% sensitive for identifying fractures of the knee with the potential relative reduction in the use of radiography to be estimated at 28%.[11]

Intended Population
[edit | edit source]

Ottawa Knee Rules in Adults

Several studies have examined the effectiveness of the Ottawa Knee Rules, with each reporting the Rules leading to a decrease in the use of knee radiography. The Rules were also associated with a reduction in waiting times and costs. Application of the Ottawa Knee Rules worldwide would be very important an advantageous in decreasing health care costs without risking the quality of patient care.[2][12]

Ottawa Knee Rules in Children

With regards to applying the Rules in children, the evidence is conflicting. In the past, several studies have been performed but all have reported varying results. Some have shown the use of the Ottawa Knee Rules in children as being accurate and efficient,[13] but many have reported the opposite as being true. Therefore, it is safer that the Ottawa Knee Rules be not used in children under the age of 18.[14]

As such, there is an important need for more concise studies to investigate the effectiveness of the Rules in children. Only when the results become consistent should a clear and general conclusion be made. Until then, the consensus is that under the age of 18 years is considered an exclusion criteria.

Criteria[edit | edit source]

If one of the following is present, radiographs are indicated:[11]

  1. Age >55 years
  2. Islolated patellar tenderness without other bone tenderness
  3. Tenderness of the fibular head
  4. Inability to flex the knee to 90°
  5. Inability to bear weight immediately after injury and in the emergency department (4 steps) regardless of limping
Areas of interest when palpating for the Ottawa Knee Rules

If any of the following are present, the Ottawa Knee Rules may be contraindicated:[15]

  1. younger then 18 year
  2. injuries greater then 7 days old
  3. re-evaluation of recent injuries
  4. altered levels of consciousness
  5. paraplegia (an impairment in motor or sensory function) of the lower extremities
  6. multiple injuries or other fractures
  7. pregnancy
  8. isolated injuries of the skin without underlying soft tissue or bone involvement:
    • superficial lacerations or skin injuries
    • abrasions
    • puncture wounds
    • burns
  1. referred from outside the hospital with radiographs

How to Perform the Examination[edit | edit source]

When the Ottawa Knee Rule is executed the following things will be done: [15]

  1. Check for sensitivity of the proximal fibula
  2. Check for sensitivity of the patella. Only examine the patella not the surrounding tissues
  3. Is the patient able to flex the knee to 90 degrees. This will be measured with a goniometer as follows:
    a. the axis of the goniometer is placed on the lateral epicondyl of the femur
    b. the stationary arm is placed on the femur and points towards the greater trochanter
    c. the moving arm is placed on the fibula and points towards the lateral malleolus
  4. Examine if the patient is able to bear weight. First, we will ask the patient if they were able to weight bear (to make 4 steps) immediately after the injury. Then ask the patient to make four steps. If the patient is unable to do this due the pain, we can conclude that this part of the examination is positive. If the patient is able to make at least four steps in the affected leg (without a limp), we can conclude that this part of the examination is negative.

We have a positive test when one (or more) of the following indications is the case:

  • when the patient indicates pain during palpation
  • when there is an increased sensitivity of the fibula
  • when the patient is unable to bring the knee in 90°flexion
  • when the patient in unable to care his own bodyweight (stepping is not possible)
  • when acute blunt injuries of the knee are present, regardless of mechanism of injury

Resources[edit | edit source]

http://www.ohri.ca/emerg/cdr/docs/cdr_knee_card.pdf

Evidence [edit | edit source]

26.4% reduction in adult patients referred for radiographs and lower medical charges when Ottawa Rules applied.[11]

46% of patients aged 3 to 18 years would not require radiograph with 92% of fracutures being identified.[16]

A systematic review by Buchmann et al found a negative result on the Ottawa knee rule test is associated with a fracture probability of less than 1.5% in an adult population.[17]

Adult Population: Sensitivity: 1.0 Specificity: .49-.56 +LR: 1.9-2.3 -LR: 0[11]

Pediatric Population:  Sensitivity:  1.0  Specificity:  .43  +LR:  1.8  -LR:  0[11]


Recent Related Research (from Pubmed)[edit | edit source]

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References[edit | edit source]

  1. ↑ Jackson JL, O'Malley PG, Kroenke, K. Evaluation of acute knee pain in primary care. Ann Intern Med. 2003 Oct 7;139(7):575-88. Review.
  2. ↑ 2.0 2.1 Stiel I, Wells G, Hoag R, Sivilotti M, Cacciotti T, Verbeek R, Greenway K, McDowell I, Cwinn A, Greenberg G, Nichol G, Michael J. Implementation of the Ottawa knee rule for the use of radiography in acute knee injuries. JAMA; 1997; 278: 2075 - 2079
  3. ↑ McCaig LF. national Hospital Ambulatory Medial Care Survey: 1992 emergency department summary. Advance Data. 1994;245:1-12.
  4. ↑ 4.0 4.1 National Center for Health Statistics. National Hospital Ambulatory Medical Care Survey 1992. Hyattsville, MD:National Center for Health Statistics; 1994.
  5. ↑ Stiell IG, Wells GA, McDowell I, et al. Use of Radiography in acute knee injuries: need for clinical decision rules. Acad Emerg Med. 1995;2:966-973.
  6. ↑ Gratton MC, Salomone JA III, Watson WA. Clinically Significant radiograph misinterpretations at an emergency medicine residency program. Ann Emerg Med. 1990;19:497-502.
  7. ↑ McConnochie KM, Roghmann KJ, Pasternack J, Monroe DJ, Monaco LP. Prediction rules for selective radiographic assessment of extremity injuries in children and adolescents. Pediatrics. 1990;86:45-57.
  8. ↑ Moloney TW, Rogers DE. Medical Technology: a different view of the contentious debate over costs. N Eng J Med. 1979;301:1413-1419.
  9. ↑ Angell M. Cost containment and the physician. JAMA. 1985;254:1203-1207.
  10. ↑ Stiell IG, Greenberg GH, Wells GA, et al. Derivation of a decision rule for the use of radiography in acute knee injuries. Ann Emerg Med. 1995;26:405-413.
  11. ↑ 11.0 11.1 11.2 11.3 11.4 Stiell IG, McKnight RD, Greenberg GH, McDowell I, Nair RC, Wells GA, Johns C, Worthington JR. Implementation of the Ottawa Ankle Rules. Journal of the American Medical Association 1994; 271:827-832.
  12. ↑ Emparanza J, Aginaga J. Validation of the Ottawa knee rules. Annals of emergency medicine; 2001; 38: 364 - 368
  13. ↑ Bulloch B, Neto G, Plint A, Lim R, Lidman P, Reed M, Nijssen-Jordan C, Tenenbein M, Klassen T. Validation of the ottawa knee rule in children: a multicenter study. Annals of Emergency Medicine; 2003; 42: 48 – 55
  14. ↑ Khine H, Dorfman D, Avner J. Applicability of Ottawa knee rule for knee injury in children. Pediatric emergency care; 2001: 17 (6): 401 - 404
  15. ↑ 15.0 15.1 Glynn P, Weisbach C. Clinical prediction rules: a physical therapy reference manual. Jones Barlett Learning; 2009: 248 pag (43 – 36) Cite error: Invalid <ref> tag; name "Glynn et al" defined multiple times with different content
  16. ↑ Khine H, Dorfman DH, Avner JR.Applicability of Ottawa knee rule for knee injury in children. PEDIATRIC EMERGENCY CARE.Vol. 17, No. 6
  17. ↑ Bachmann LM, Haberzeth S, Steurer J, ter Riet, G. The accuracy of the Ottawa knee rule to rule out knee fractures:fckLRa systematic review. Ann Intern Med. 2004 Jan 20;140(2):121-4. Review.


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