Journal of Emergencies, Trauma, and Shock
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 Table of Contents    
REVIEW ARTICLE  
Year : 2021  |  Volume : 14  |  Issue : 4  |  Page : 222-226
Approach to suspected physeal fractures in the emergency department


1 Department of Paediatric Orthopaedics, King George's Medical University, Lucknow, Uttar Pradesh, India
2 Department of Emergency Medicine, Pediatric Emergency Medicine, CS Mott Children's Hospital of Michigan, Ann Arbor, Michigan, Florida State University, Tallahassee, Florida, USA
3 Department of Emergency Medicine, Florida State University College of Medicine, Tallahassee, Florida, USA
4 Department of Emergency Medicine, Florida State University, Sarasota Memorial Hospital, Sarasota, Florida, USA

Click here for correspondence address and email

Date of Submission17-Mar-2021
Date of Acceptance12-Jun-2021
Date of Web Publication24-Dec-2021
 

   Abstract 


Growth plate (physeal) fractures are defined as a disruption in the cartilaginous physis of bone with or without the involvement of epiphysis or metaphysis. These represent around 15-18% of all pediatric fractures. It is important to diagnose physeal injury as early as possible, as misdiagnosis or delay in diagnosis may result in long term complications. Physeal injuries may not be initially obvious in children who present with periarticular trauma, and a high index of suspicion is important for diagnosis. Differential diagnosis for a Salter-Harris fracture includes a ligamentous sprain, acute osteomyelitis, or an extraphyseal fracture such as a Torus fracture. Salter-Harris I & Salter-Harris II growth plate fractures commonly are commonly managed by closed manipulation, reduction & immobilization. These are relatively stable injuries and can be retained by adequate plaster. Salter-Harris III & Salter-Harris IV fractures require anatomical reduction with the maintenance of congruity of joint. Physeal fractures can have many complications such as malunion, bar formation, acceleration of growth of physis, posttraumatic arthritis, ligament laxity and shortening of the bone. The key to well-healing fractures is successful anatomic reduction and patients must have regular follow-up for these injuries.

Keywords: Emergency, fractures, pediatric, physeal

How to cite this article:
Singh A, Mahajan P, Ruffin J, Galwankar S, Kirkland C. Approach to suspected physeal fractures in the emergency department. J Emerg Trauma Shock 2021;14:222-6

How to cite this URL:
Singh A, Mahajan P, Ruffin J, Galwankar S, Kirkland C. Approach to suspected physeal fractures in the emergency department. J Emerg Trauma Shock [serial online] 2021 [cited 2022 May 16];14:222-6. Available from: https://www.onlinejets.org/text.asp?2021/14/4/222/333692





   Introduction Top


Growth plate (physeal) fractures are defined as a disruption in the cartilaginous physis of bone with or without the involvement of epiphysis or metaphysis.[1] These represent around 15%–18% of all pediatric fractures.[2] Other common types of fractures in childhood are torus fractures, greenstick fractures, and plastic deformities.[3]

The ligaments surrounding the growth plates are five times stronger than the growth plate itself, thus making the growth plate more susceptible to disruption which is in contrast to similar injuries in adults. Physeal injuries can be differentiated from sprains or ligament injuries by eliciting point tenderness – physeal tenderness will be present at bone; however, ligamentous tenderness will be present at the joint line.

Physeal fractures are not equal to any other adult articular or periarticular fractures because of acceptability criterion, remodeling potential, different fixation devices, and alignment goals as well as different follow-up protocols.[4] Bone age assessment using Greulich–Pyle atlas and charts can give an idea about growth remaining. If surgery is required, then any delay will worsen the prognosis.


   Burden of Disease Top


The true burden of physeal injury is unknown, and studies reveal that 30% of all fractures involved the physis,[3] with ~44% involving the distal radius.[5] Males are twice more affected than females and consistent with maturity of the bones, females are affected during younger age (11–12 years) than males (12–14 years). Injuries in the upper extremities are more common than the lower extremities, which is the same for both male and female. In children, ligaments are stronger and more compliant than in adults. Therefore, ligaments tolerate mechanical forces better than the physes. Epiphyseal fractures or apophyseal detachments are much more common than ligamentous injuries during childhood.


   Pediatric Skeletal Anatomy and Physiology Top


There may be two growth plates present in the immature skeletal, namely horizontal (physis) and spherical growth plate (for epiphyseal growth). The horizontal growth plate is also mentioned as cartilaginous growth plate, physis, or epiphyseal plate. The epiphysis and epiphyseal plates are not synonyms. The area of a bone between the physis and the joint directly adjacent to it is the epiphysis. The epiphyseal plate is part of the metaphysis and is a hyaline cartilage plate where new growth takes place.


   Structure of Physis Top


Basically, there are three zones in every physis: the resting zone or reserve zone, the proliferative zone, and the zone of hypertrophy.

The zone of hypertrophy can further be divided into the maturation zone, the degeneration zone, and the provisional calcification zone.


   Reserve/Resting Zone Top


This zone is immediately next to the epiphysis and consists of irregularly scattered chondrocytes. This layer supplies chondrocytes for proliferation and stores materials like lipid, glycogen, and proteoglycan. Injuries to this layer can cause cessation of growth.


   Proliferative Zone Top


This zone is responsible for the number of chondrocytes. The cells are arranged in well-defined columns and provide a matrix for future growth.


   Hypertrophic Zone Top


This zone is neighboring the metaphysis and subdivided into maturation, degeneration, and provisional calcification. Degeneration of cells releases calcium from matrix vesicles. The metaphyseal blood vessels penetrate this layer which allows for the growth of chondroblasts and osteoblasts. Finally, this leads to bone formation. This zone is the vulnerable part of the physis structure and is typically a source of fractures or adjustments (i.e. widening of physis in rickets).


   Periphery of Physis Top


There are two components of the periphery of physis:

  1. Groove of Ranvier
  2. Peripheral ring (of LaCroix).


Ranvier's groove is the wedged-shaped zone of cells that passes through the epiphysis. It provides the cells to the periphery of physis so that bone can grow in width. The peripheral ring is responsible for the overall stability of physis.[6]

The perichondral artery is the major source of nutrition of the growth plate.


   Biomechanics Top


The physeal fractures occur through various layers which depend upon the type of load applied: [7]

  1. Compression force leads to fractures in the provisional calcification portion of the zone of hypertrophy
  2. Shear force leads to disruption in the zone of hypertrophy
  3. Tension force leads to fractures in the proliferative zone.



   Etiology Top


The causes of physeal injuries include trauma, either acute or overuse injury, infection, burns, tumor, or irradiation.

Among these, traumatic injuries are most common. The prognosis of these fractures is not only dependent on the fracture pattern but also upon the age of the patient, health of surrounding tissues, method and reduction quality, immobilization method and length, and the involvement of physis.[8]


   Classification Top


The most prevalent classification was proposed by Robert Salter and W. Robert Harris (1963), which is commonly known as Salter–Harris Classification.[9] It subdivides the physeal injuries into following:

  1. Type I – In this injury, the fracture line traverses through the hypertrophic layer of physis, separating epiphysis from the metaphysis. These fractures are more common in younger patients, who have a thicker physis.[2] Clinical findings suggesting this injury can be more evident than radiological findings. Soft tissue swelling and tenderness may be the only evidence of injury. Sometimes, enlargement or new bone formation along the anatomical margins will be found in radiographs. The prognosis for these injuries is generally excellent
  2. Type II – In this injury, a fracture will split the physis partially and will include a small piece of the metaphysis. This metaphyseal fragment is known as a Thurston Holland fragment. The fragmentary periosteum is always intact, which makes it easier to reduce. This type of physeal injury is the most common (75%). The prognosis of these injuries is good
  3. Type III – This type of injury demonstrates a fracture line traversing through physis and extending into the joint through the epiphysis. This may lead to articular discontinuity, posttraumatic arthritis, and growth arrest.[2] The most common example of this type of injury is a Tillaux fracture in skeletally immature patients. The prognosis of these injuries is poor unless reduced anatomically
  4. Type IV – This fracture goes obliquely through the metaphysis, passes through the physis, and goes into the joint through the epiphysis. The Thurstan Holland sign (fragment) is also seen in this fracture pattern. Medial malleolus fractures in children are commonly Type IV fractures
  5. Type V – This type of fracture is typically a compression or crush injury to the physis. It is frequently challenging to diagnose this pattern. Follow-up and reexamination may demonstrate asymmetric Park–Harris growth lines showing a portion of physis growing normally; however, the opposite side showing impairment of growth. It is a rare type of injury pattern that has the worst prognosis.


A mnemonic “SALTER” has been used to help remember SH Types I–V.(I) S = straight across, (II) A = above, (III) L = lower or below, (IV) T = through, and (V) ER = erasure of growth plate or “crush.”


   Limitations of Salter–Harris Classification Top


Thawrani et al.[10] examined the intra- and interobserver reliability of categorizing distal tibial fractures and establishing varying rates of intraobserver reliability and legitimately robust rates of interobserver reliability. Another limitation to the Salter–Harris classification system is that it cannot be used as an independent predictor of fracture prognosis.[2] Tzavellas et al.[11] observed moderate interobserver reliability that was improved with greater rater's experience. The Type II and Type III fractures were the best scored regardless of the rater's experience. Type I, IV, and V when in doubt require additional imaging.


   Salter Type VI Top


This type is typically not included in Salter–Harris Classification. It describes an injury to peripheral physis. It may lead to peripheral bony bridge formation, further leading to considerable angular deformity. Some authors refer to this type of injury as a Kessel fracture.[12]

Ogden[13] added three more types of fractures to Salter–Harris Classification:

  1. Ogden VII – Epiphyseal fracture that does not involve the physis
  2. Ogden VIII – Metaphyseal fracture affecting later growth
  3. Ogden IX – Periosteal damage affecting later growth.


In an epidemiological study of physeal injuries, Peterson[14] maintains Salter–Harris I to IV as Peterson II to V and further supplements two more types:

  1. Peterson I – Metaphyseal fractures that extend up to physis
  2. Peterson VI – Articular and epiphyseal loss.


Briefly, there is also the AO pediatric comprehensive classification of long bone fractures which defines fractures as simple, wedge, and complex.


   Diagnosis Top


Clinical findings

It is important to diagnose physeal injury as early as possible, as misdiagnosis or delay in diagnosis may result in long-term complications. These children present with point tenderness following traumatic injury. Local swelling may be present, as well as loss of function of the extremity. Ligamentous laxity may not be diagnostic of physeal injury. If the child has localized tenderness at bone or physeal area, this injury can be indicative of physeal injury. If there is ligamentous tenderness or tenderness over the joint line, this may be more suggestive of a sprain.

Radiologic findings

A high degree of clinical suspicion is needed to diagnose physeal injury. In the presence of clinical suspicion, but with negative oblique radiographs or opposite side comparison radiographs, computer tomography (CT) or magnetic resonance imaging (MRI) is indicated for further diagnosis. It is typically recommended to image the joint above and the joint below the fracture to avoid missing associated injuries. In children <6 months of age, high-resolution ultrasound may be used to diagnose physeal disruption. A study of 163 children with suspected fractures found that ultrasound was the most reliable for the detection of simple humeral and femoral diaphyseal fractures.[15] It was also found to be reliable for fracture of the forearm. Ultrasound was found to be less dependable as a study for nondisplaced epiphyseal fractures such as Salter–Harris Type I, fractures of small bones of the hand and foot, and compound injuries. It can also differentiate physeal injury from ligamentous injury. CT may also be indicated to study fracture patterns requiring fixation. Bone scans are not of much help in making the diagnosis of physeal injuries.[16],[17],[18] Advanced imaging (including CT and MRI) shows greater average displacement than plain radiographs.[19]


   Differential Diagnosis Top


Differential diagnosis for a Salter–Harris fracture includes a ligamentous sprain, acute osteomyelitis, or an extraphyseal fracture such as a Torus fracture. A ligamentous sprain may have similar presentation and the patient may be unable to bear weight. However, the patient should not have bony point tenderness. A patient who has osteomyelitis may have other symptoms such as fever, swelling, and elevated laboratories such as a sed rate or C-reactive protein. They should also lack a history of an acute injury. A Torus fracture is a type of extraphyseal fracture that as the name suggests, does not involve the growth plate.


   Management Top


Primary management

All patients must be assessed in emergency department as per or Advanced Trauma Life Support Protocol. In the secondary survey, one must try to rule out physeal injury in all pediatric injured patients.

Conservative

Very frequently, physeal fractures can be treated nonoperatively. The factors affecting decisions about modalities are the following: [20]

  1. Age of patient
  2. Site of injury
  3. Mechanism of injury
  4. Fracture pattern
  5. Growth potential of involved physis
  6. Plane of deformity
  7. Condition of surrounding soft tissue.


SH I and SH II growth plate fractures are commonly used to manage closed manipulation, reduction, and immobilization. These are relatively stable injuries and can be retained by adequate plaster. Often, periosteal flaps and soft tissue covering the fracture can also interfere, making it challenging to reduce absolutely. This condition may require surgical intervention. To assess the efficacy of the reduction, these injuries must be reevaluated within seven to 10 days.[21]

Manipulation with closed reduction and traction must be made very carefully and gently in a fully relaxed patient to avoid any iatrogenic secondary injury. Repeated reduction attempts that can damage the germinal physis layer are preferable, however, to less than adequate reductions. More emphasis should be on traction rather than a forceful reduction to avoid crushing of physis. Absolute contraindications for reduction of displaced growth plate fractures are few. Relative contraindications for growth plate fracture reduction would be Salter–Harris I and II fractures with clinically insignificant displacement. Furthermore, fractures with greater displacement with late presentation (more than 1 week) should not be manipulated.[19] SH III and SH IV fractures require anatomical reduction with the maintenance of congruity of joint. Any malreduction may lead to malunion resulting in the disruption of the biomechanics of joint.

More serious injuries, particularly with intra-articular fractures, involve anatomical management with open reduction and internal fixation, which may avoid the physis crossover. If surgery is required, the treating surgeon must be aware of the remodeling potential of fracture, different surgical approaches for children than adults, need to use smooth K-wires in place of screws, and the appropriate times required for healing.[4] Preferably smooth pins should be parallel to physis in epiphysis and metaphysis. The oblique wires should only be passed if stability is compromised. Periosteal stripping should be avoided. Forceful manipulation must be avoided.


   Prognosis Top


The prognosis of physeal injury depends on:

  1. Physeal damage severity
  2. Skeletal patient age (as per SH)
  3. Fracture site.


Children still growing with the potential for remodeling have a better prognosis. If the deformity is along the line of movements of joints, then the remodeling will be better. The site of fracture also influences remodeling. The distal femoral, proximal femoral, and proximal tibial physeal injuries have a greater rate of complications (as high as 40%).


   Recent Advances Top


Tissue engineering

Many cartilage regeneration studies have been focused on joint cartilage, but some of these studies may also refer to cartilage plate growth. Some strategies such as implantation of chondrogenic cells may be a viable option for physeal injury. The future promises unique intracellular signaling solutions to posttraumatic growth plate disturbances.

Growth plate transplantations

Several materials (fat, fascia, silicon, bone cement) have been used to fill the gaps in physis after bar excision, but cartilage may prove ideal for this purpose.[22] Experiments have been conducted to evaluate its efficacy in physeal injury cases.

Physis distractions

Some studies are being conducted to study the role of physeal distraction to stimulate physis in physeal fractures.[23]


   Complications Top


There can be several complications related to physeal injury. Some of these are:

  1. Physeal fractures may lead to bar formation or malunion if not treated well. This may result in growth discrepancy or angular deformities. Barmada et al. found that the incidence of premature physis closure (PPC) occurred on SH I and II fractures with a physitic residual gapping of more than 3 mm following reduction was 60%; however, the incidence of a PPC in the gap of <3 mm was 17%. When residual gapping was reduced visibly, in most cases, the periosteum was kept within the physis. Another study, Rohmiller et al. found that the rate of PPC in distal tibial fractures varied based on the mechanism of injury. In supination-external-rotation type injury, the rate of PPC was 35% compared to 54% rate of PPC in pronation-abduction type injuries.[24] A study done by Cottalorda et al. showed that 48 children who had Type III or Type IV distal tibial and medial malleolus fractures underwent arthrotomy to achieve anatomical reduction if the displacement was >1 mm, and they had no ankle stiffness at follow-up[25]
  2. In a small percentage of patients, there can be an acceleration of growth of physis resulting in apparent lengthening[25]
  3. Hardware-related complications
  4. Iatrogenic damage of physis
  5. Arthrofibrosis resulting in stiffness of joint
  6. Secondary posttraumatic arthritis of the joint can occur, especially from Salter–Harris Type III fractures if left untreated[26]
  7. Possible shortening of the bone and ligament laxity can occur. A study by Torg et al. demonstrated two patients with Salter–Harris Type III fractures of the medial femoral condyle with minimal femoral shortening and anterior cruciate ligament laxity status post fracture reduction.[27]


Follow-up and Rehabilitation

  1. SH 1 and 2 should be immobilized for 3–6 weeks
  2. SH 3 and 4 should be immobilized for 4–8 weeks.


A patient can start unrestricted physical activities only after 4–6 weeks of implant removal. Follow-up radiographs are done at 6 months and 12 months (which may be done at 2 years as well).


   Special Situations Top


Any fracture in a nonmobile, nonweight-bearing, or nonambulatory child should raise suspicion for child abuse.


   Conclusion Top


Physeal injuries may not be obvious in children presenting with periarticular trauma. A high index of suspicion during evaluation is most important. Successful anatomic reduction is the key to healing. Regular follow-up of these injuries is a must to deal with any long-term complications.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
   References Top

1.
Rang M, editor. The Growth Plate and It's Disorders. Baltimore: Williums and Wikins; 1969.  Back to cited text no. 1
    
2.
Cepela DJ, Tartaglione JP, Dooley TP, Patel PN. Classifications in brief: Salter-Harris classification of pediatric physeal fractures. Clin Orthop Relat Res 2016;474:2531-7.  Back to cited text no. 2
    
3.
Boutis, K. (2020). Pediatric Orthopedic Emergencies. Tintinalli's Emergency Medicine: A Comprehensive Study Guide, 9e, JE Tintinalli, et al, Editors.  Back to cited text no. 3
    
4.
Mann DC, Rajmaria S. Distributiona of physial and nonphyseal fractures in 2,650 long bone fractures in children aged 0-16 years. J Paediatr Orthop 1990;10:713-6.  Back to cited text no. 4
    
5.
Neer CS, Horowitz BS. Fractures of the proximal humeral epiphyseal plate. Clin Orthop Relat Res 1965;41:24-31.  Back to cited text no. 5
    
6.
Langenskiöld A. Role of the ossification groove of ranvier in normal and pathologic bone growth: A review. J Pediatr Orthop 1998;18:173-7.  Back to cited text no. 6
    
7.
Jones C, Wolf M, Herman M. Acute and chronic growth plate injuries. Pediatr Rev 2017;38:129-38.  Back to cited text no. 7
    
8.
Bright RW. Physeal injuries. In: Rockwood CA Jr., Wilkins KE, Beaty JH, editors. Fractures in Children. 3rd ed. Philadelphia:Lipincott-Raven; 1991. p. 87-186.  Back to cited text no. 8
    
9.
Salter RB, Harris WR. Injuries involving the epiphysel plate. J Bone Joint Surg Am 1963;45-A: 587-622.  Back to cited text no. 9
    
10.
Thawrani D, Kuester V, Gabos PG, Kruse RW, Littleton AG, Rogers KJ, et al. Reliability and necessity of computerized tomography in distal tibial physeal injuries. J Pediatr Orthop 2011;31:745-50.  Back to cited text no. 10
    
11.
Tzavellas AN, Kenanidis E, Potoupnis M, Pellios S, Tsiridis E, Sayegh F. Inter-observer and intra-observer reliability of Salter-Harris classification of physel injuries. Hippokratia 2016;2:222-26.  Back to cited text no. 11
    
12.
Havranek P, Pest T. Salter (rang) type-6 physeal injuries. Eur J Paediatr Surg 2010;20:174-77.  Back to cited text no. 12
    
13.
Orden JA. Injuries to nthe growth mechanism of the immuture skeleton. Skeletol Redial 1981;6:237-53.  Back to cited text no. 13
    
14.
Peterson HA. Physeal fractures: Part 2. Two previously unclassified types. J Pediatr Orthop 1994;14:431-8.  Back to cited text no. 14
    
15.
Hübner U, Schlicht W, Outzen S, Barthel M, Halsband H. Ultrasound in the diagnosis of fractures in children. J Bone Joint Surg Br 2000;82:1170-3.  Back to cited text no. 15
    
16.
Boutis K, Plint A, Stimec J, Miller E, Babyn P, Schuh S, et al. Radiograph-negative lateral ankle injuries in children: Occult growth plate fracture or sprain? JAMA Pediatr 2016;170:e154114.  Back to cited text no. 16
    
17.
Ho-Fung VM, Zapala MA, Lee EY. Musculoskeletal traumatic injuries in children: Characteristic imaging findings and mimickers. Radiol Clin North Am 2017;55:785-802.  Back to cited text no. 17
    
18.
Boutis K, Narayanan UG, Dong FF, Mackenzie H, Yan H, Chew D, et al. Magnetic resonance imaging of clinically suspected Salter-Harris I fracture of the distal fibula. Injury 2010;41:852-6.  Back to cited text no. 18
    
19.
Pennock, A. T., Ellis, H. B., Willimon, S. C., Wyatt, C., Broida, S. E., Dennis, M. M., & Bastrom, T. (2017). Intra-articular physeal fractures of the distal femur: a frequently missed diagnosis in adolescent athletes. Orthopaedic journal of sports medicine, 5(10), 2325967117731567.  Back to cited text no. 19
    
20.
Frydoni, M. B., & Esmaeilnejad-Ganji, S. M. (2021). Surgical and nonsurgical treatments for proximal femur fractures: A narrative review. Journal of Medical Sciences, 41(2), 53.  Back to cited text no. 20
    
21.
Nguyen JC, Markhardt BK, Merrow AC, Dwek FR. Imaging of paediatric growth plate disturbances. Musculoskelet Imaging 2017;37:1791-808.  Back to cited text no. 21
    
22.
Tobita M, Ochi M, Uchio Y, Mori R, Iwasa J, Katsube K, et al. Treatment of growth plate injury with autogenous chondrocytes: A study in rabbits. Acta Orthop Scand 2002;73:352-8.  Back to cited text no. 22
    
23.
Barmada A, Gaynor T, Mubarak SJ. Premature physeal closure following distal tibia physeal fractures: A new radiographic predictor. J Pediatr Orthop 2003;23:733-9.  Back to cited text no. 23
    
24.
Rohmiller MT, Gaynor TP, Pawelek J, Mubarak SJ. Salter-Harris I and II fractures of the distal tibia: Does mechanism of injury relate to premature physeal closure? J Pediatr Orthop 2006;26:322-8.  Back to cited text no. 24
    
25.
Cottalorda J, Béranger V, Louahem D, Camilleri JP, Launay F, Diméglio A, et al. Salter-Harris type III and IV medial malleolar fractures: Growth arrest: Is it a fate? A retrospective study of 48 cases with open reduction. J Pediatr Orthop 2008;28:652-5.  Back to cited text no. 25
    
26.
Basener CJ, Mehlman CT, DiPasquale TG. Growth disturbance after distal femoral growth plate fractures in children: A meta-analysis. J Orthop Trauma 2009;23:663-7.  Back to cited text no. 26
    
27.
Torg JS, Pavlov H, Morris VB. Salter-Harris type-III fracture of the medial femoral condyle occurring in the adolescent athlete. J Bone Joint Surg Am 1981;63:586-91.  Back to cited text no. 27
    

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Correspondence Address:
Dr. Courtney Kirkland
2904 Satsuma Dr, Sarasota 34239, Florida
USA
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/JETS.JETS_40_21

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    Abstract
   Introduction
   Burden of Disease
    Pediatric Skelet...
   Structure of Physis
   Reserve/Resting Zone
   Proliferative Zone
   Hypertrophic Zone
   Periphery of Physis
   Biomechanics
   Etiology
   Classification
    Limitations of S...
   Salter Type VI
   Diagnosis
    Differential Dia...
   Management
   Prognosis
   Recent Advances
   Complications
   Special Situations
   Conclusion
    References

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