Posterior triangle of the neck

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The posterior triangle forms the posterior compartment of the neck and is separated from the anterior triangle by the sternocleidomastoid muscle.The triangles of the neck are surgically focussed, first described from early dissection-based anatomical studies which predated cross-sectional anatomical description based on imaging (see deep spaces of the neck).

Boundaries

~~Anterior~~

anterior: ~~Posterior~~posterior border of sternocleidomastoid~~Posterior~~
posterior: ~~Anterior~~anterior border of trapezius~~Inferior~~
inferior: ~~Middle~~middle third of the clavicle~~Roof~~
roof: ~~Skin~~skin, superficial fascia &and the investing layer of deep cervical fascia~~Floor~~
floor: ~~Prevertebral~~prevertebral fascia overlying splenius capitis, semispinalis capitis, levator scapulae, scalenus medius & and scalenus anterior

The inferior belly of the omohyoid that crosses the triangle divides it into an inferior supraclavicular and superior occipital triangles.

~~Clinical significance~~

The posterior triangle contains level 5 lymph node chains. These include spinal accessory and transverse cervical nodes. Depending on the location of the nodes above or below the accessory nerve, they are sub grouped as level 5a (above) or level 5b (below).

-<p>The posterior triangle forms the posterior compartment of the neck and is separated from the anterior triangle by the sternocleidomastoid muscle.</p><h6>Boundaries</h6><p>Anterior: Posterior border of sternocleidomastoid</p><p>Posterior: Anterior border of trapezius</p><p>Inferior: Middle third of the clavicle</p><p>Roof: Skin, superficial fascia & investing layer of deep cervical fascia</p><p>Floor: Prevertebral fascia overlying splenius capitis, semispinalis capitis, levator scapulae, scalenus medius & scalenus anterior</p><p>The inferior belly of the omohyoid that crosses the triangle divides it into an inferior <a href="/articles/supraclavicular-triangle">supraclavicular</a> and superior <a title="Occipital triangle" href="/articles/occipital-triangle">occipital triangles</a>. <!--[if gte mso 9]><xml>
+<p>The <strong>posterior triangle</strong> forms the posterior compartment of the neck and is separated from the <a href="/articles/anterior-triangle-1">anterior triangle</a> by the <a href="/articles/sternocleidomastoid-muscle">sternocleidomastoid muscle</a>. <!--[if gte mso 9]><xml>
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+</xml><![endif]-->The triangles of the neck are surgically focussed, first described from early dissection-based anatomical studies which predated cross-sectional anatomical description based on imaging (see <a href="/articles/deep-spaces-of-the-head-and-neck">deep spaces of the neck</a>).<!--[if gte mso 9]><xml>
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+<![endif]--></p><h4>Boundaries</h4><ul>
+<li>anterior: posterior border of <a href="/articles/sternocleidomastoid-muscle">sternocleidomastoid</a>
+</li>
+<li>posterior: anterior border of <a href="/articles/trapezius-muscle">trapezius</a>
+</li>
+<li>inferior: middle third of the <a href="/articles/clavicle">clavicle</a>
+</li>
+<li>roof: skin, superficial fascia and the investing layer of <a href="/articles/deep-cervical-fascia">deep cervical fascia</a>
+</li>
+<li>floor: <a href="/articles/prevertebral-fascia">prevertebral fascia</a> overlying <a href="/articles/splenius-capitis-muscle">splenius capitis</a>, <a href="/articles/transversospinalis-group">semispinalis capitis</a>, <a href="/articles/levator-scapulae">levator scapulae</a>, <a href="/articles/scalenus-medius-muscle">scalenus medius</a> and <a href="/articles/scalenus-anterior-muscle-1">scalenus anterior</a>
+</li>
+</ul><p>The inferior belly of the <a href="/articles/omohyoid-muscle">omohyoid</a> that crosses the triangle divides it into an inferior <a href="/articles/supraclavicular-triangle">supraclavicular</a> and superior <a href="/articles/occipital-triangle">occipital triangles</a>. <!--[if gte mso 9]><xml>
-<![endif]--> </p><h6>Clinical significance</h6><p>The posterior triangle contains level 5 lymph node chains. These include spinal accessory and transverse cervical nodes. Depending on the location of the nodes above or below the accessory nerve, they are sub grouped as level 5a (above) or level 5b (below). </p><p></p><p></p>
+<![endif]--> </p><h4>Contents</h4><p>The posterior triangle contains level 5 <a href="/articles/lymph-node-levels-of-the-neck">lymph node chains</a>. These include spinal accessory and transverse cervical nodes. Depending on the location of the nodes above or below the accessory nerve, they are sub grouped as level 5a (above) or level 5b (below). </p><p></p><p></p>

References changed:

4. Bari M. Logan, Ralph T. Hutchings. McMinn's Color Atlas of Foot and Ankle Anatomy E-Book. (2011) ISBN: 9780702051647 - <a href="http://books.google.com/books?vid=ISBN9780702051647">Google Books</a>
5. Mcminn. Last's Anatomy. (2003) ISBN: 9780729537520 - <a href="http://books.google.com/books?vid=ISBN9780729537520">Google Books</a>
3. Stephanie Ryan, Michelle McNicholas, Stephen J. Eustace. Anatomy for Diagnostic Imaging. (2011) ISBN: 9780702029714 - <a href="http://books.google.com/books?vid=ISBN9780702029714">Google Books</a>
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Logan BM, Reynolds PA, Hutchings RT. (2004). Head and Neck Anatomy, 3rd edition, London: Elsevier
McMinn RMH. (2011). Last's Anatomy Regional and Applied, 9th edition, London: Elsevier
Ryan S, McNicholas M, Eustace S. (2011). Anatomy for Diagnostic Imaging, 3rd edition, London: Elsevier
Butler P, Mitchell AWM, Healy JC. (2012). Applied Radiological Anatomy, 2nd edition, Cambridge: Cambridge University Press.
Borley NR, Collins P, Crossman AR, Gatzoulis MA, Healy JC, Johnson D, Mahadevan V, Newell RLM, Wigley CB. (2008). Gray's Anatomy, fortieth edition, London: Elsevier.