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Os Acromiale

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Patient-facing topic on os acromiale — failed fusion of an acromial ossification centre that may cause shoulder pain and contribute to subacromial impingement.

Updated Aug 2026
Isang guhit-kamay na ilustrasyon ng isang anatomikal na guhit ng os acromiale, ang acromion na may hiwalay na hindi pa nagkakaisang fragment ng buto.
Os acromiale: ang harapang bahagi ng acromion ay hindi nag-ugnay sa natitirang bahagi ng acromion sa panahon ng paglaki ng balangkas ng katawan. Kieran Hirpara 4.0

Ang pahinang ito ay isinalin ng makina at hindi pa nasusuri ng isang doktor. Ang bersyong Ingles ang siyang opisyal.

Ano ang nararamdaman mo

Maaaring mapansin mo ang sakit sa itaas na bahagi ng iyong balikat. Ang lugar na ito ay nasa direkta sa itaas ng pangunahing ball-and-socket joint. Ang hindi komportableng pakiramdam ay madalas na malalim at nakakaramdam ng sakit. Maaari ring maging matulis ito kapag gumagalaw ka ng iyong braso sa mga partikular na paraan. Maraming tao ang naglalarawan ng pakiramdam ng kawalan ng katatagan o pag-click sa lugar na iyon. Nangyayari ito dahil ang maliit na fragment ng buto ay hindi ganap na nakakonekta sa natitirang bahagi ng scapula.

Ang iyong mga sintomas ay madalas na lumala sa mga gawain sa itaas ng ulo. Ang pag-abot pataas upang kunin ang isang mataas na shelf o ang pag-angat ng mga bagay sa itaas ng iyong ulo ay maaaring mag-trigger ng sakit. Maaari mo ring maramdaman ang hindi komportableng pakiramdam kapag nag-aabot ka sa likod ng iyong likod, tulad ng pag-zip ng bra o pagtutukoy ng isang damit. Ang mga galaw na ito ay humuhuli sa lugar kung saan ang fragment ng buto ay nagtatagpo sa natitirang bahagi ng balikat. Kung mayroon kang rotator cuff tear, na karaniwan sa kondisyong ito, maaaring mas malala ang sakit. Ang abnormal na galaw sa site ng koneksyon ay maaaring mag-irritate sa mga nakapaligid na tissue, na nagdudulot ng pamamaga at karagdagang hindi komportableng pakiramdam.

Ang sakit sa gabi ay isa pang karaniwang reklamo. Maaaring mahirap kang matulog sa apektadong gilid. Ang presyon mula sa paghiga sa iyong balikat ay maaaring mag-aggravate sa inflamed na lugar. May mga tao na gumising na may stiff na balikat sa umaga. Ang sakit ay maaaring bumaba habang gumagalaw ka sa loob ng araw, ngunit madalas itong bumabalik pagkatapos ng matagalang aktibidad. Kung ikaw ay isang propesyonal na tennis player, maaaring payuhan ng iyong surgeon ang pag-iwas sa surgery, dahil ang pahinga at therapy ay madalas na tumutulong sa pamamahala ng mga sintomas. Gayunpaman, kung ang mga conservative na paggamot ay hindi tumutulong, maaaring isaalang-alang ang mga surgical na pagpipilian tulad ng pag-alis ng bahagi ng fragment o pag-aayos nito sa lugar upang bawasan ang iyong sakit at mapabuti ang function.

Ano ang nangyayari talaga

Ang iyong balikat ay isang kumplikadong ball-and-socket joint. Ang acromion ay isang butong arko sa itaas ng iyong scapula. Sa karamihan ng mga tao, nabubuo ang butong ito bilang iisang piraso noong bata pa. Sa ilang mga kaso, nananatiling hindi pagsama ang isang maliit na hiwalay na piraso ng buto, na tinatawag na os acromiale. Nangyayari ito sa humigit-kumulang 2.13% ng mga pasyente na may problema sa balikat na nakakuha ng MRI.

Isipin ang hindi pagsamang pirasong ito bilang isang maluwag na bato sa sapatos. Nasa tamang posisyon ito kung saan dapat itong bahagi ng pangunahing buto, ngunit gumagalaw ito nang kaunti pa sa dapat. Ang karagdagang galaw na ito ay maaaring mag-irita sa mga tissue sa paligid nito. Ang synchondrosis ay ang fibrous na koneksyon sa pagitan ng piraso at ng pangunahing buto. Habang karaniwang matatag ang koneksyong ito, maaari itong masaktan sa pamamagitan ng trauma sa bihirang mga kaso.

Ang abnormal na galaw na ito ay madalas na nagdudulot ng isang sekundaryong problema: impingement. Ang impingement ay nangyayari kapag ang mga buto o tissue ay nagkukuskos sa isa’t isa sa isang makitid na espasyo. Habang gumagalaw ang iyong braso, maaaring mahuli o mahimpit ng maluwag na piraso ang mga malambot na tissue sa ilalim nito. Ang paghimpit na ito ay isang karaniwang sanhi ng sakit at pamamaga sa balikat.

Ang rotator cuff ay isang grupo ng mga tendon na nagpapatibay sa iyong balikat. Ang mga tendon na ito ay gumagana tulad ng mga lubid na humahawak sa ulo ng upper arm bone sa loob ng socket. Dahil ang os acromiale ay nasa direkta sa itaas ng mga tendon na ito, maaaring masira o magkasuot ang mga ito dahil sa abnormal na galaw. Ipinapakita ng mga pag-aaral na madalas na nauugnay ang os acromiale sa mga sugat sa rotator cuff. Ang paghimpit mula sa maluwag na piraso ay maaaring mag-ambag sa mga putol sa mga kritikal na hibla ng tendon.

Kung mayroon kang kondisyong ito, maaaring maranasan mo ang sakit kapag itinataas ang iyong braso sa itaas. Ang hindi komportableng pakiramdam ay galing sa friction at pressure sa maingay na espasyo sa itaas ng iyong balikat. Ang pag-unawa sa mekanikal na isyung ito ay tumutulong upang maipaliwanag kung bakit minsan hindi sapat ang simpleng pahinga. Ang pisikal na iritasyon mula sa gumagalaw na piraso ng buto ay madalas na nangangailangan ng target na paggamot upang matugunan ang mga sintomas.

Ano ang maaari naming gawin dito

Ang ginagamit na pamamaraan ni Dr. Kieran Hirpara, isang surgyon sa itaas na ekstremitas sa Mater Private Hospital Rockhampton, ay sumasalamin sa paraan ng pamamahala namin sa kondisyong ito sa aming klinika. Dumating ang mga pasyente sa aming alaga sa pamamagitan ng referral mula sa isang GP o physiotherapist. Simulan namin ang isang komprehensibong pagsusuri, kasama ang kasaysayan, pagsusuri, at imahen kung kinakailangan, upang kumpirmahin ang diagnosis. Para sa mga matagal nang o degenerative na isyu, karaniwang nagsisimula kami sa non-operative na paggamot. Kasama nito ang pagbabago sa iyong mga gawain, physiotherapy o hand therapy, paggamit ng splint, at mga injeksyon. Isasama namin ang operasyon lamang kung hindi nagbibigay ng sapat na pagpapabuti ang mga hakbang na ito. Para sa mga acute na structural na problema, maaaring irekomenda agad ang operasyon.

Maaari kang magsimula sa pamamagitan ng pagbabago sa iyong pang-araw-araw na mga gawain upang maiwasan ang mga galaw na nagdudulot ng sakit. Layunin ng physiotherapy na palakasin ang mga kalamnan sa paligid ng iyong balikat upang bawasan ang stress sa os acromiale. Ito ay isang karagdagang piraso ng buto sa iyong scapula na maaaring magdulot ng iritasyon. Karaniwang inirerekomenda namin na bigyan mo ang konservatibong pamamaraang ito ng makatarungang pagsubok bago isaalang-alang ang ibang mga opsyon. Kung patuloy ang sakit, maaaring talakayin namin ang medikal na pamamahala. Maaaring kasama nito ang gamot pang-sakit at anti-inflammatory na mga gamot upang matulungan ang pagkontrol sa mga sintomas. Maaaring mag-alok ng mga injeksyon, tulad ng cortisone, upang bawasan ang pamamaga at magbigay ng pansamantalang ginhawa. Ang mga tratamientong ito ay tumutulong sa pamamahala ng hindi komportableng pakiramdam ngunit hindi nagbabago sa pangunahing istruktura ng buto.

Isasama ang operasyon kapag naabot na ng konservatibong paggamot ang hangganan nito at patuloy na malaki ang iyong mga sintomas. Talakayin namin ito bilang isang shared na desisyon, binibigyang-balansyo ang mga potensyal na benepisyo laban sa mga panganib. Ang layunin ay bawasan ang sakit at ibalik ang function kapag hindi na epektibo ang mga non-surgical na paraan. Gabayin ka namin ng aming koponan sa mga susunod na hakbat batay sa iyong partikular na pangangailangan at sa mga natuklasan mula sa iyong pagsusuri.

Ano ang inaasahan

Ang os acromiale ay isang karagdagang piraso ng buto sa iyong scapula. Ito ay apektado ng humigit-kumulang 1 sa 50 na tao na may mga isyu sa balikat. Maaari kang magkaroon ng sakit sa magkabilang panig, dahil ito ay bilateral sa 62% ng mga kaso. Ang pirasong ito ay maaaring magkuskos sa ibang mga buto, na nagdudulot ng iritasyon o mga luha sa rotator cuff.

Kung mayroon kang mga sintomas, malamang na sisimulan ng iyong surgeon ang non-surgical na paggamot. Kasama rito ang pahinga at anti-inflammatory na gamot. Para sa karamihan ng mga tao, ang paraang ito ay tumutulong sa pamamahala ng sakit. Kung hindi gumana ang mga hakbang na ito, maaaring isaalang-alang ang operasyon upang alisin o ayusin ang piraso. Karaniwang nagdudulot ito ng pagbaba ng mga sintomas at mas mahusay na pag-andar ng balikat.

Ang paggaling mula sa operasyon ay kinabibilangan ng isang panahon ng lokal na pagkadura sa site. Isa sa apat na pasyente ang nakakaranas nito. Ang magandang balita ay ang pagkadurang ito ay natatapos sa sarili nito sa paglipas ng panahon para sa karamihan ng mga pasyente. Inaasahan mo ang unti-unting pagbabalik sa normal na mga gawain habang ang lugar ay gumagaling.

Kung mayroon kang reverse shoulder replacement, ang pagkakaroon ng os acromiale ay hindi negatibong apektado ang iyong resulta. Ang prosedurang ito ay nananatiling isang ligtas at epektibong opsyon para sa iyo. Siguraduhin ng iyong surgeon na gumana ang joint replacement nang maayos kahit may karagdagang piraso ng buto.

Para sa mga propesyonal na manlalaro ng tennis, karaniwang hindi inirerekomenda ang operasyon. Ang mga hinihingi ng isport ay maaaring lumampas sa mga benepisyo ng pag-aayos ng piraso. Sa mga kasing ito, ang pamamahala ng mga sintomas nang walang operasyon ay madalas na ang piniling landas.

Sa kabuuan, ang pananaw ay positibo para sa mga nangangailangan ng paggamot. Karamihan sa mga tao ay nakakahanap ng ginhawa mula sa sakit at pagpapabuti ng galaw. Gabay ng iyong surgeon ang iyong sa pinakamainam na opsyon para sa iyong partikular na sitwasyon. Inaasahan mo ang patuloy na pagpapabuti sa kaginhawaan ng iyong balikat sa loob ng mga linggo hanggang buwan.

Kailan pumunta sa doktor

Kumonsulta sa iyong doktor kung mayroon kang patuloy na sakit sa balikat na hindi gumagaling kahit magpahinga. Humingi ng pagsusuri ng espesyalista kung mapansin mo ang kahinaan, kawalan ng katatagan, o pakiramdam ng pagkakasara o pagbagsak ng balikat. Ang mga sintomas na nakakaapekto sa iyong tulog o trabaho ay dapat ding pansinin. Ang biglaang paglala ng sakit ay dapat agad suriin.

Ang os acromiale ay isang karagdagang piraso ng buto sa balikat. Ito ay nangyayari sa humigit-kumulang 2% ng mga tao na may problema sa balikat. Madalas itong nauugnay sa mga sugat sa rotator cuff, na mga sugat sa mga kalamnan ng balikat. Maaaring mangyari ang mga sugat na ito dahil ang karagdagang buto ay nagdudulot ng hindi normal na galaw at panghihiganti. Ang maagang pagsusuri ay tumutulong upang kumpirmahin ang diagnosis at gabayan ang iyong plano ng paggamot.

Reviewed by Dr Kieran Hirpara · 7 August 2026.

Want the clinical detail? Read the clinician version.

Talk to your treating clinician for advice specific to you.

For an appointment with the CQ Hand + Upper Limb team, ask your GP about a referral or visit www.cqupperlimb.com.

Evidence & references

This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.

Overview

  • In Thai patients with shoulder problems requiring MRI evaluation, the prevalence of os acromiale was 2.13% [1].
  • Os acromiale is associated with rotator cuff injuries [5].
  • A multicenter study aimed to determine the prevalence of and factors associated with os acromiale in the Japanese population [6].
  • Operative management of a symptomatic os acromiale that has failed initial nonoperative treatment leads to decreased symptoms and improvement in clinical outcomes [2].
  • Surgical options for symptomatic os acromiale include arthroscopic sub-total excision [16].
  • Surgical options for symptomatic os acromiale include arthroscopic subacromial decompression of stable fragments [16].
  • Surgical options for symptomatic os acromiale include open reduction and internal fixation of unstable fragments [16].
  • Surgical treatment is usually not indicated for os acromiale in the professional tennis player [7].
  • Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate [12].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients after reverse total shoulder arthroplasty [3].
  • Postoperative local tenderness at the os acromiale resolves spontaneously over time in the majority of patients after reverse total shoulder arthroplasty [3].
  • The presence of os acromiale does not appear to have a negative impact on clinical outcomes after reverse total shoulder arthroplasty [4].
  • The outcome of reverse total shoulder arthroplasty does not seem to be negatively affected by the presence of an os acromiale [9].

Anatomy & Pathophysiology

  • The prevalence of os acromiale in Thai patients with shoulder problems requiring MRI evaluation is 2.13% [1].
  • A tear of the rotator cuff may often be associated with os acromiale, likely due to impingement from abnormal motion at the fibrous union site [8].
  • Fused os acromiale, which has not been described previously, might be mistaken for a free ossicle in the clinical setting [10].
  • Awareness of the os acromiale in the young athlete is crucial to confirm diagnosis through appropriate clinical examination and image studies [11].
  • The synchondrosis of an os acromiale can be injured following trauma, though rarely [13].
  • Postoperative local tenderness at the os acromiale resolves spontaneously over time in the majority of patients [3].
  • Reverse shoulder arthroplasty improves range of motion, decreases pain, and increases patient satisfaction in patients with os acromiale and cuff tear arthropathy [24].

Classification

  • Awareness of the os acromiale in the young athlete, appropriate clinical examination, and image studies are crucial to confirm diagnosis [11].
  • Meta-os acromiale is the rarest subtype of os acromiale [15].

Clinical Presentation

  • The prevalence of os acromiale in Thai patients with shoulder problems requiring MRI evaluation was 2.13% [1].
  • The presence of os acromiale does not appear to have a negative impact on clinical outcomes after reverse total shoulder arthroplasty (rTSA) [4].
  • The outcome of reverse total shoulder arthroplasty (RTSA) does not seem to be negatively affected by the presence of an os acromiale [9].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients following rTSA [3].
  • Surgical treatment is usually not indicated for os acromiale in professional tennis players [7].
  • Awareness of the os acromiale, appropriate clinical examination, and image studies are crucial to confirm diagnosis in young athletes [11].
  • Liberson reviewed 1800 shoulder girdles and identified an incidence of os acromiale of 1.4% [14].
  • The lesion of os acromiale is bilateral in 62% of patients according to Liberson's review [14].

Investigations

  • Appropriate radiographic investigation for os acromiale injury includes axillary views [13].

Treatment

  • Surgical options for symptomatic os acromiale include arthroscopic sub-total excision, arthroscopic subacromial decompression of stable fragments, and open reduction and internal fixation of unstable fragments [16].
  • Open reduction and internal fixation using cannulated screws or tension band wiring have superior outcomes in the literature in the treatment of symptomatic os acromiale [19].
  • A new arthroscopic technique of fixation of os acromiale with absorbable screws provides promising clinical, cosmetic, and radiologic results with high patient satisfaction [17].
  • A symptomatic os acromiale in a competitive female fastball pitcher was treated successfully with open reduction and internal fixation [21].
  • Special consideration must be given to the type of tension-band construct used to achieve adequate compression and fixation for meta-os acromiale, the rarest subtype of os acromiale [15].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients but resolves spontaneously over time in the majority of patients [3].
  • The presence of os acromiale does not appear to have a negative impact on the clinical outcomes after reverse total shoulder arthroplasty (rTSA) [4].

Complications

  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients following reverse total shoulder arthroplasty [3].
  • Reverse total shoulder arthroplasty remains a safe and effective treatment option in the presence of os acromiale [4].
  • The incidence of os acromiale identified by Liberson was 1.4% [14].
  • The lesion of os acromiale was bilateral in 62% of patients in Liberson's review [14].

Recovery

  • Reverse total shoulder arthroplasty (rTSA) remains a safe and effective treatment option in patients with os acromiale [4].

Key Evidence

  • [L3] In Thai patients with shoulder problems who required MRI evaluation, the prevalence of os acromiale was 2.13%. [1] (10.1177/23259671221078806)
  • [L4] Operative management of a symptomatic os acromiale that has failed initial nonoperative treatment leads to decreased symptoms and improvement in clinical outcomes. [2] (10.1016/j.jse.2019.05.047)
  • [L3] Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients but resolves spontaneously over time in the majority of patients. [3] (10.1177/2325967120965131)
  • [L4] The presence of os acromiale does not appear to have a negative impact on the clinical outcomes after surgery and rTSA remains a safe and effective treatment option. [4] (10.1016/j.xrrt.2025.01.002)
  • [L3] The study supports previous findings that os acromiale is associated with rotator cuff injuries. [5] (10.1016/j.jseint.2025.05.015)
  • [L3] This multicenter study aimed to determine the prevalence of and factors associated with os acromiale in the Japanese population. [6] (10.1016/j.jse.2025.01.008)
  • [L4] Surgical treatment is usually not indicated for os acromiale in the professional tennis player. [7] (10.1177/2325967118773723)
  • [L4] A tear of the rotator cuff may often be associated with os acromiale, likely due to impingement from abnormal motion at the fibrous union site. [8] (10.2106/00004623-198466080-00029)
  • [L4] The outcome of RTSA does not seem to be negatively affected by the presence of an os acromiale. [9] (10.1016/j.jse.2017.02.012)
  • [L4] An anatomical study showed that fused os acromiale, which has not been described previously, might be mistaken for a free ossicle in the clinical setting. [10] (10.2106/00004623-200003000-00010)
  • [L4] Awareness of the os acromiale in the young athlete, appropriate clinical examination, and image studies are crucial to confirm diagnosis. [11] (10.1016/j.jseint.2020.02.008)
  • [L4] Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate. [12] (10.1186/s12891-021-04841-1)
  • [L4] This case highlights that the synchondrosis of an os acromiale can be injured following trauma, though rarely, and emphasizes the need for appropriate radiographic investigation including axillary views and a flexible surgical approach. [13] (10.1016/j.jse.2008.02.012)
  • [L4] Meta–os acromiale is the rarest subtype of os acromiale, and special consideration must be given to the type of tension-band construct used to achieve adequate compression and fixation. [15] (10.1177/03635465211028238)
  • [L5] Surgical options for symptomatic os acromiale include arthroscopic sub-total excision, arthroscopic subacromial decompression of stable fragments, and open reduction and internal fixation of unstable fragments. [16] (10.5435/jaaos-d-17-00011)
  • [L4] This new arthroscopic technique of fixation of os acromiale with absorbable screws provides promising clinical, cosmetic, and radiologic results with high patient satisfaction. [17] (10.1016/j.jse.2011.12.011)
  • [L4] Open reduction and internal fixation using cannulated screws, or tension band wiring have superior outcomes in the literature in the treatment of symptomatic os acromiale. [19] (10.1302/2058-5241.4.180100)
  • [L4] A symptomatic os acromiale in a competitive female fastball pitcher was treated successfully with open reduction and internal fixation. [21] (10.1177/0363546506288305)
  • [L4] Reverse shoulder arthroplasty improved ROM, decreased pain, and increased patient satisfaction in patients with os acromiale and cuff tear arthropathy. [24] (10.5397/cise.2019.00409)

References

[1] Prevalence of Os Acromiale in Thai Patients With Shoulder Problems: A Magnetic Resonance Imaging Study. Orthopaedic Journal of Sports Medicine. 2022. DOI: 10.1177/23259671221078806

[2] Os acromiale: systematic review of surgical outcomes. Journal of Shoulder and Elbow Surgery. 2020. DOI: 10.1016/j.jse.2019.05.047

[3] Os Acromiale in Reverse Total Shoulder Arthroplasty: A Cohort Study. Orthopaedic Journal of Sports Medicine. 2020. DOI: 10.1177/2325967120965131

[4] Clinical implications of reverse total shoulder arthroplasty with an os acromiale: a systematic review. JSES Reviews, Reports, and Techniques. 2025. DOI: 10.1016/j.xrrt.2025.01.002

[5] Prevalence and factors associated with os acromiale: a multicenter study. JSES International. 2025. DOI: 10.1016/j.jseint.2025.05.015

[6] The prevalence and associated factors of os acromiale: a multicenter study. Journal of Shoulder and Elbow Surgery. 2025. DOI: 10.1016/j.jse.2025.01.008

[7] Os Acromiale in Professional Tennis Players. Orthopaedic Journal of Sports Medicine. 2018. DOI: 10.1177/2325967118773723

[8] Rotator cuff tears associated with os acromiale.. The Journal of Bone & Joint Surgery. 1984. DOI: 10.2106/00004623-198466080-00029

[9] Reverse shoulder arthroplasty in patients with os acromiale. Journal of Shoulder and Elbow Surgery. 2017. DOI: 10.1016/j.jse.2017.02.012

[10] Os Acromiale: Frequency, Anatomy, and Clinical Implications. The Journal of Bone and Joint Surgery-American Volume*. 2000. DOI: 10.2106/00004623-200003000-00010

[11] The unstable os acromiale: a cause of pain in the young athlete. JSES International. 2020. DOI: 10.1016/j.jseint.2020.02.008

[12] Os acromiale may be a contraindication of the clavicle hook plate: case reports and literature review. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04841-1

[13] Fracture of an os acromiale with associated rupture of the coracoclavicular ligaments. Journal of Shoulder and Elbow Surgery. 2008. DOI: 10.1016/j.jse.2008.02.012

[14] Types of os acromiale according to Liberson. 2006.

[15] Rare Symptomatic Meta–Os Acromiale in an Athlete. The American Journal of Sports Medicine. 2021. DOI: 10.1177/03635465211028238

[16] Symptomatic, Unstable Os Acromiale. Journal of the American Academy of Orthopaedic Surgeons. 2018. DOI: 10.5435/jaaos-d-17-00011

[17] Arthroscopically assisted internal fixation of the symptomatic unstable os acromiale with absorbable screws. Journal of Shoulder and Elbow Surgery. 2012. DOI: 10.1016/j.jse.2011.12.011

[19] Os acromiale: a review of its incidence, pathophysiology, and clinical management. EFORT Open Reviews. 2019. DOI: 10.1302/2058-5241.4.180100

[21] Surgical Stabilization of Os Acromiale in a Fast-Pitch Softball Pitcher. The American Journal of Sports Medicine. 2006. DOI: 10.1177/0363546506288305

[24] Reverse shoulder arthroplasty with os acromiale. Clinics in Shoulder and Elbow. 2020. DOI: 10.5397/cise.2019.00409

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c. Copyright and Similar Rights means copyright and/or similar rights closely related to copyright including, without limitation, performance, broadcast, sound recording, and Sui Generis Database Rights, without regard to how the rights are labeled or categorized. For purposes of this Public License, the rights specified in Section 2(b)(1)-(2) are not Copyright and Similar Rights.

d. Effective Technological Measures means those measures that, in the absence of proper authority, may not be circumvented under laws fulfilling obligations under Article 11 of the WIPO Copyright Treaty adopted on December 20, 1996, and/or similar international agreements.

e. Exceptions and Limitations means fair use, fair dealing, and/or any other exception or limitation to Copyright and Similar Rights that applies to Your use of the Licensed Material.

f. Licensed Material means the artistic or literary work, database, or other material to which the Licensor applied this Public License.

g. Licensed Rights means the rights granted to You subject to the terms and conditions of this Public License, which are limited to all Copyright and Similar Rights that apply to Your use of the Licensed Material and that the Licensor has authority to license.

h. Licensor means the individual(s) or entity(ies) granting rights under this Public License.

i. NonCommercial means not primarily intended for or directed towards commercial advantage or monetary compensation. For purposes of this Public License, the exchange of the Licensed Material for other material subject to Copyright and Similar Rights by digital file-sharing or similar means is NonCommercial provided there is no payment of monetary compensation in connection with the exchange.

j. Share means to provide material to the public by any means or process that requires permission under the Licensed Rights, such as reproduction, public display, public performance, distribution, dissemination, communication, or importation, and to make material available to the public including in ways that members of the public may access the material from a place and at a time individually chosen by them.

k. Sui Generis Database Rights means rights other than copyright resulting from Directive 96/9/EC of the European Parliament and of the Council of 11 March 1996 on the legal protection of databases, as amended and/or succeeded, as well as other essentially equivalent rights anywhere in the world.

l. You means the individual or entity exercising the Licensed Rights under this Public License. Your has a corresponding meaning.

Section 2 -- Scope.

a. License grant.

1. Subject to the terms and conditions of this Public License, the Licensor hereby grants You a worldwide, royalty-free, non-sublicensable, non-exclusive, irrevocable license to exercise the Licensed Rights in the Licensed Material to:

a. reproduce and Share the Licensed Material, in whole or in part, for NonCommercial purposes only; and

b. produce, reproduce, and Share Adapted Material for NonCommercial purposes only.

2. Exceptions and Limitations. For the avoidance of doubt, where Exceptions and Limitations apply to Your use, this Public License does not apply, and You do not need to comply with its terms and conditions.

3. Term. The term of this Public License is specified in Section 6(a).

4. Media and formats; technical modifications allowed. The Licensor authorizes You to exercise the Licensed Rights in all media and formats whether now known or hereafter created, and to make technical modifications necessary to do so. The Licensor waives and/or agrees not to assert any right or authority to forbid You from making technical modifications necessary to exercise the Licensed Rights, including technical modifications necessary to circumvent Effective Technological Measures. For purposes of this Public License, simply making modifications authorized by this Section 2(a) (4) never produces Adapted Material.

5. Downstream recipients.

a. Offer from the Licensor -- Licensed Material. Every recipient of the Licensed Material automatically receives an offer from the Licensor to exercise the Licensed Rights under the terms and conditions of this Public License.

b. No downstream restrictions. You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, the Licensed Material if doing so restricts exercise of the Licensed Rights by any recipient of the Licensed Material.

6. No endorsement. Nothing in this Public License constitutes or may be construed as permission to assert or imply that You are, or that Your use of the Licensed Material is, connected with, or sponsored, endorsed, or granted official status by, the Licensor or others designated to receive attribution as provided in Section 3(a)(1)(A)(i).

b. Other rights.

1. Moral rights, such as the right of integrity, are not licensed under this Public License, nor are publicity, privacy, and/or other similar personality rights; however, to the extent possible, the Licensor waives and/or agrees not to assert any such rights held by the Licensor to the limited extent necessary to allow You to exercise the Licensed Rights, but not otherwise.

2. Patent and trademark rights are not licensed under this Public License.

3. To the extent possible, the Licensor waives any right to collect royalties from You for the exercise of the Licensed Rights, whether directly or through a collecting society under any voluntary or waivable statutory or compulsory licensing scheme. In all other cases the Licensor expressly reserves any right to collect such royalties, including when the Licensed Material is used other than for NonCommercial purposes.

Section 3 -- License Conditions.

Your exercise of the Licensed Rights is expressly made subject to the following conditions.

a. Attribution.

1. If You Share the Licensed Material (including in modified form), You must:

a. retain the following if it is supplied by the Licensor with the Licensed Material:

i. identification of the creator(s) of the Licensed Material and any others designated to receive attribution, in any reasonable manner requested by the Licensor (including by pseudonym if designated);

ii. a copyright notice;

iii. a notice that refers to this Public License;

iv. a notice that refers to the disclaimer of warranties;

v. a URI or hyperlink to the Licensed Material to the extent reasonably practicable;

b. indicate if You modified the Licensed Material and retain an indication of any previous modifications; and

c. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.

2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.

3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.

4. If You Share Adapted Material You produce, the Adapter's License You apply must not prevent recipients of the Adapted Material from complying with this Public License.

Section 4 -- Sui Generis Database Rights.

Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:

a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database for NonCommercial purposes only;

b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and

c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.

For the avoidance of doubt, this Section 4 supplements and does not replace Your obligations under this Public License where the Licensed Rights include other Copyright and Similar Rights.

Section 5 -- Disclaimer of Warranties and Limitation of Liability.

a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU.

b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU.

c. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.

Section 6 -- Term and Termination.

a. This Public License applies for the term of the Copyright and Similar Rights licensed here. However, if You fail to comply with this Public License, then Your rights under this Public License terminate automatically.

b. Where Your right to use the Licensed Material has terminated under Section 6(a), it reinstates:

1. automatically as of the date the violation is cured, provided it is cured within 30 days of Your discovery of the violation; or

2. upon express reinstatement by the Licensor.

For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.

Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

Creative Commons may be contacted at creativecommons.org.