Play Video
1
The Acromion Os Acromiale - Everything You Need To Know - Dr. Nabil Ebraheim
The Acromion Os Acromiale - Everything You Need To Know - Dr. Nabil Ebraheim
::2011/04/27::
Play Video
2
Surface Anatomy: Acromion Process
Surface Anatomy: Acromion Process
::2013/09/20::
Play Video
3
acromion
acromion
::2008/03/26::
Play Video
4
clavicula acromion cabeza humeral espina de la escapula  borde inferior y lateral de la escapula
clavicula acromion cabeza humeral espina de la escapula borde inferior y lateral de la escapula
::2012/11/30::
Play Video
5
Glenoid Cavity, Acromion, and Coracoid Process with Skeleton Premium
Glenoid Cavity, Acromion, and Coracoid Process with Skeleton Premium
::2013/02/13::
Play Video
6
Fracture of Acromion Process of the Scapula
Fracture of Acromion Process of the Scapula
::2014/04/25::
Play Video
7
Kines_Shoulder Palpation_David S.
Kines_Shoulder Palpation_David S.
::2008/08/08::
Play Video
8
Deslizamiento clavícula-acromion
Deslizamiento clavícula-acromion
::2013/03/30::
Play Video
9
ACROMION - TSMU FRESHERS PARTY 2012
ACROMION - TSMU FRESHERS PARTY 2012
::2012/11/12::
Play Video
10
Shoulder - Sub Acromion Decompression - Impingement
Shoulder - Sub Acromion Decompression - Impingement
::2013/06/04::
Play Video
11
Blue Star "Acromion" at Marquee Theater AZ
Blue Star "Acromion" at Marquee Theater AZ
::2014/03/31::
Play Video
12
Acromion palpation
Acromion palpation
::2013/01/11::
Play Video
13
Basic surface anatomy of shoulder
Basic surface anatomy of shoulder
::2007/11/06::
Play Video
14
Acro Duo (Acromion) - Turn me on
Acro Duo (Acromion) - Turn me on
::2011/12/11::
Play Video
15
Trailer Makrab Acromion-FKH 47
Trailer Makrab Acromion-FKH 47
::2014/03/07::
Play Video
16
Acromion - Mourner
Acromion - Mourner
::2013/10/26::
Play Video
17
bursal bunching acromion
bursal bunching acromion
::2009/10/08::
Play Video
18
Acromion New Year Party
Acromion New Year Party
::2014/01/02::
Play Video
19
Acromion - RIVIERA - Colors Of Friendship Winter 2011
Acromion - RIVIERA - Colors Of Friendship Winter 2011
::2011/12/29::
Play Video
20
ACROMION - Mistake
ACROMION - Mistake
::2012/08/29::
Play Video
21
Broken shoulder - AC joint - Clavicula - Acromion - Need Help - Surgery
Broken shoulder - AC joint - Clavicula - Acromion - Need Help - Surgery
::2012/03/08::
Play Video
22
Kines_Shoulder_Palpations_Denise
Kines_Shoulder_Palpations_Denise
::2008/08/12::
Play Video
23
10 Degree Decline Acromion Grip Fat Gripz Bench Press
10 Degree Decline Acromion Grip Fat Gripz Bench Press
::2010/01/31::
Play Video
24
Acromion : Bakti Sosial FK UNS 2012
Acromion : Bakti Sosial FK UNS 2012
::2013/06/01::
Play Video
25
Acromion 2010
Acromion 2010
::2014/08/10::
Play Video
26
RIVIERA 2011 - ACROMION
RIVIERA 2011 - ACROMION
::2011/12/29::
Play Video
27
Via Acromion.wmv
Via Acromion.wmv
::2012/05/30::
Play Video
28
Penampilan Acromion FKH 47 Jawa Barat part1
Penampilan Acromion FKH 47 Jawa Barat part1
::2014/07/12::
Play Video
29
1 Acromion claviculair,omo serato claviculair et  le gléno humeral
1 Acromion claviculair,omo serato claviculair et le gléno humeral
::2012/01/24::
Play Video
30
Acromion Grip Barbell Bench Press
Acromion Grip Barbell Bench Press
::2009/12/21::
Play Video
31
acromion in German
acromion in German
::2014/08/13::
Play Video
32
B 057 Schulterdach Verkalkung  - SD PAL /B 057 Shoulder calcification acromion  - SD PAL
B 057 Schulterdach Verkalkung - SD PAL /B 057 Shoulder calcification acromion - SD PAL
::2011/04/18::
Play Video
33
acromion (process) in German
acromion (process) in German
::2014/08/13::
Play Video
34
Acromion New Years Party Teaser
Acromion New Years Party Teaser
::2013/12/31::
Play Video
35
Videogiornale di Ortopedia : attrito acromion omerale (1991)
Videogiornale di Ortopedia : attrito acromion omerale (1991)
::2013/05/29::
Play Video
36
Acromion Photography Club goes to Ulun Danu
Acromion Photography Club goes to Ulun Danu
::2013/06/09::
Play Video
37
Caverna - Acromion
Caverna - Acromion
::2012/06/01::
Play Video
38
"El Acromion" GO Choroy corp. (1 de 2 ) moby films comedy
"El Acromion" GO Choroy corp. (1 de 2 ) moby films comedy
::2007/05/03::
Play Video
39
ACROMION 2010
ACROMION 2010
::2014/03/11::
Play Video
40
Burdeos - Acromion
Burdeos - Acromion
::2011/10/13::
Play Video
41
Definición de acromion
Definición de acromion
::2012/09/10::
Play Video
42
Arthroscopic Subacromial Decompression: Spur Removal
Arthroscopic Subacromial Decompression: Spur Removal
::2012/10/21::
Play Video
43
Medical Advice On Acromion
Medical Advice On Acromion
::2014/08/30::
Play Video
44
Doom 3 BFG Part 1: Acromion-attached semi-directed lux projection apparatus.
Doom 3 BFG Part 1: Acromion-attached semi-directed lux projection apparatus.
::2013/08/14::
Play Video
45
Trailer "El Acromion" GoChoroy Corp.- 2007-
Trailer "El Acromion" GoChoroy Corp.- 2007-
::2007/04/22::
Play Video
46
Acromion, sacrum and subsidence were found out 3
Acromion, sacrum and subsidence were found out 3
::2008/10/01::
Play Video
47
Shoulder acromion: Type I, II, III
Shoulder acromion: Type I, II, III
::2012/10/03::
Play Video
48
Shoulder Impingement syndrome; shoulder motion and acromion change
Shoulder Impingement syndrome; shoulder motion and acromion change
::2012/10/11::
Play Video
49
acromion and scapula orif
acromion and scapula orif
::2013/04/01::
Play Video
50
3era edad: (1) Medición de acromion a acromion
3era edad: (1) Medición de acromion a acromion
::2010/10/15::
NEXT >>
RESULTS [51 .. 101]
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Acromion
Acromion of left scapula01.png
Left scapula. Posterior view. Acromion shown in red.
Acromion of scapula06.png
Latin Acromion
Gray's p.203
Anatomical terms of bone

In human anatomy, the acromion (from Greek: akros, "highest", ōmos, "shoulder", plural: acromia) is a bony process on the scapula (shoulder blade). Together with the coracoid process it extends laterally over the shoulder joint. The acromion is a continuation of the scapular spine, and hooks over anteriorly. It articulates with the clavicle (collar bone) to form the acromioclavicular joint.

Structure[edit]

The acromion forms the summit of the shoulder, and is a large, somewhat triangular or oblong process, flattened from behind forward, projecting at first lateralward, and then curving forward and upward, so as to overhang the glenoid cavity.[1]

Surfaces[edit]

Its superior surface, directed upward, backward, and lateralward, is convex, rough, and gives attachment to some fibers of the deltoideus, and in the rest of its extent is subcutaneous. Its inferior surface is smooth and concave.[1]

Borders[edit]

Its lateral border is thick and irregular, and presents three or four tubercles for the tendinous origins of the deltoid. Its medial border, shorter than the lateral, is concave, gives attachment to a portion of the trapezius, and presents about its center a small oval surface for articulation with the acromial end of the clavicle.[1]

Variation[edit]

There are three morphologically distinct types of acromia and a correlation between these morphologies and rotator cuff tear:[2]

Type Prevalence Angle of
anterior slope
Rotator
cuff tear
Flat 17.1% 13.18 3.0%
Curved 42.9% 29.98 24.2%
Hooked 39.3% 26.98 69.8%

Os acromiale[edit]

The acromion has four ossification centers called (from tip to base) pre-acromion, meso-acromion, meta-acromion, and basi-acromion. In most cases, the first three fuse at 15–18 years, whereas the base part fuses to the scapular spine at 12 years. However, in between 1% and 15% of cases, this osseous union fails and the acromion remains a separate bone. This condition is referred to as os acromiale, but rarely causes pain. Earlier estimates of its prevalence were as low as 1.4%, and this higher estimate was made by Sammarco in the year 2000, based on radiographic and anatomical studies.[3][4]

Four types of os acromiale can be distinguished:[5]

  • A non-union between the meso- and meta-acromia, the most common or typical os acromiale
  • A non-union between the pre- and meso-acromia
  • A non-union between the pre- and meso-acromia; and between the meso- and meta-acromia, atypical
  • A non-union between the pre- and meso-acromia; between the pre- and meso-acromia; and between the meta- and basi-acromia

This feature was common in skeletons recovered from the Mary Rose shipwreck: it is thought that in those men, much archery practice from childhood on with the mediaeval war bow (which needs a pull three times as strong as the modern standard Olympic bow) pulled at the acromion so much that it prevented bony fusion of the acromion with the scapula.

Although historically regarded as an incidental finding, the os acromiale may occasionally produce symptoms from subacromial impingement or instability at the site of non-union.[6] Dynamic US evaluation may demonstrate hypermobility of the non-union during shoulder motion or graded compression with the probe in symptomatic individuals.[7]

In other animals[edit]

The acromion process of bats (Mammalia: Chiroptera) is particularly elongated compared to that of humans.

Turtles have an acromion that forms the anterior part of the triradiate pectoral girdle (together with the coracoid and scapula). In this highly specialized endoskeletal structure, the scapula is a dorsal (directed upwards) process attached to the first rib; the coracoid is a posteroventral (directed backward and down) process; and the acromion is a medioventral (directed inwards and down) process (also known as the prescapular process) located at the base of the scapula. This had led to some controversy regarding the evolutionary origin of turtles, because in both pareiasaurs and non-mammalian therapsids the acromion is located at the dorsal tip of the scapula. [8]

In modern turtles, the acromion projects ventrally and articulates with the plastron (the flat lower part of the shell), but it evolved in a common ancestor of pareiasaurs and turtles long before the plastron. In these primitive ancestors, the acromion projected forward to form a strong and flexible articulation between the shoulder girdle and the clavicle. Notwithstanding these changes, the acromion of turtles retains its original function, to support the shoulder girdle and increase stride length. [9]

Additional images[edit]

Notes[edit]

This article incorporates text from a public domain edition of Gray's Anatomy.

  1. ^ a b c Gray's Anatomy 1918, see infobox
  2. ^ Habermeyer, Magosch & Lichtenberg 2006, pp. 1–3
  3. ^ Warner, Beim & Higgins 1998, Introduction
  4. ^ Sammarco, VJ (March 2000). "Os acromiale: frequency, anatomy, and clinical implications". J Bone Joint Surg Am 82 (3): 394–400. PMID 10724231. Retrieved March 2, 2013. 
  5. ^ Habermeyer, Magosch & Lichtenberg 2006, p. 4
  6. ^ Kurtz CA, Humble BJ, Rodosky MW, Sekiya JK. Symptomatic os acromiale. J Am Acad Orthop Surg 2006; 14:12-9.
  7. ^ Arend CF. Ultrasound of the Shoulder. Master Medical Books, 2013. Chapter on os acromiale available at ShoulderUS.com
  8. ^ Rieppel & Reisz 1999
  9. ^ Lee 1996, Abstract
  • Habermeyer, Peter; Magosch, Petra; Lichtenberg, Sven (2006). Classifications and Scores of the Shoulder. Heidelberg: Springer. ISBN 978-3-540-24350-2. 
  • Lee, Michael S. Y. (January 22, 1996). "The Homologies and Early Evolution of the Shoulder Girdle in Turtles". Proc. R. Soc. Lond. B 263 (1366): 111–117. doi:10.1098/rspb.1996.0018. 
  • Rieppel, Olivier; Reisz, Robert R. (1999). "The Origin and Early Evolution of Turtles". Annual Review of Ecology and Systematics 30: 1–22. doi:10.1146/annurev.ecolsys.30.1.1. 
  • Warner, Jon J.P.; Beim, Gloria M.; Higgins, Laurence (September 1998). "The Treatment of Symptomatic Os Acromiale". The Journal of Bone and Joint Surgery 80: 1320–6. 

External links[edit]

Wikipedia content is licensed under the GFDL License
Powered by YouTube
LEGAL
  • Mashpedia © 2014