![Anterior ramus
Transverse process ] of thoracic nerve
Superior costotransverse ligament
Radiate ligament of head of rib
Subcostal1----,-,=
Anterior longitudinal ligament
sels and nerve
inches of intercostal
vessels and nerve
Communicating branches /
(rami communicantes) ~Splanchnic nerve
Anterior View Sympathetic trunk](https://image.slidesharecdn.com/intercostalspaces-avinash-231117185119-d5e64184/85/Intercostal-Spaces-Avinash-pdf-17-320.jpg)
Intercostal Spaces - Avinash.pdf
- 1. Thoracic Wall Coverings • Skin – Thin anteriorly & thick posteriorly, variable hair distribution • Superficial Fascia – More dense posteriorly • Deep Fascia – Thin , ill defined for free movement of chest for breathing • Extrinsic muscles –Upper limb , Back, Abdomen & Head & Neck
- 2. -- -------- ------ ------- Supraclavicular nerves - .... T2 -------·--------- - ----- 3 ---·---- - - (i;:·- - - - - -~ -- -- :' -,- ....:---- ; 5 -- - -- - --------- 6 -- - -----7 8 Lateral - --- cutaneous ------ ~ ----.._ 9 branches of thoracic nerves 10 Go'.)~ Lateral cutaneous _ branches of twelfth ...._ Lateral femoral cutaneous nerve t---- - -++- Femoral branch of genitofemoral nerve ........ .......
- 3. Intercostal Spaces • Eleven (11) intercostal spaces on each side • Last two spaces are open in front Features of Space • Each directed downward & forward • Narrow towards vertebral column & broad towards sternum, widest at costo-chondral junction • Posterior part is inter-osseous while ant part is inter- cartilaginous Contents – Intercostal muscles , vessels & nerves
- 4. Intercostal Spaces Typical I/C space Spaces b/w typical ribs & transversed by nerves & vessels & confined to thoracic wall Boundaries of a typical I/c space – 3rd to 6th • Above – Sharp lower margin of upper rib & its cartilage • Below – Blunt upper margin of lower rib & its cartilage • In front – Lateral border of sternum b/w costal notches • Behind – Body of corresponding thoracic vertebra
- 5. Intercostal muscles Arranged in three sheets from outside inward • External Intercostal • Internal Intercostal • Transverses thoracis – intercostalis intimi Subcostalis sternocostalis Main action Prevent retraction during inspiration & bulging during expiration of the intercostal spaces
- 7. l vessels lntercostal nerve Innermost interrosla/ - ,.,,,.• External intercosta lntercosta J External Intercostal Origin:Lower border of the rib above. Insertion:Outer lip of upper border of rib below. Extent:From costocondral junction anteriorly to tubercle of rib posteriorly. Medial to costochondral junction replaced by external (Ant.) intercostal membrane. Direction of fibres: Downwards and laterally at the back and Downwards, forwards and medially in front.
- 8. l ~ssels lntercostaf nerve Innermost intercosfal fntema, intercostal External intercost lntercosta af INTERNAL INTERCOSTAL MUSCLE Origin: Floor of costal groove of rib above. Insertion: Superior border of rib below (inner to the attachment of external intercostal muscle). Extent:From lateral border of sternum anteriorly to angle of rib posteriorly. Medial to it, replaced by internal(Posterior) intercostal membrane. Direction of fibres: At right angle to the direction of external intercostal.
- 9. vessels lntercostal nerve Innermost inten;ostal External intercostal INNERMOST INTERCOSTAL (Intercostalis Intimi) Origin: Upper margin of subcostal groove of rib above. Insertion: Superior border of rib below (inner to the attachment of internal intercostal muscle), Extent: Present in middle two fourths of the lower intercostal spaces. Poorly developed or even absent in the upper spaces. Direction of fibres: Same as internal intercostal (at right angle to the direction of external intercostal).
- 10. or TI1oracic ~lall Internal 7 Sternocostalis Present on the inner surface of anterior thoracic wall. Origin: Lower 1/3 of posterior surface of body of sternum, Posterior surface of xiphoid & posterior surfaces of costal cartilages of 4th to 7th ribs. Insertion: Lower border and posterior surfaces costal cartilages of 2nd to 6th ribs. Attachments are variable and may even differ on the two sides. Direction of fibres:Lowest fibres are horizontal, become gradually oblique and upper most fibres are directed upwards and laterally.
- 11. r--:=:::.:~~L Tra t/Jo Anterior Vi , "'· ~ - Subcostalis Present on the inner aspect of intercostal spaces posteriorly. Origin:Inner surface of rib above, near its angle. Insertion: Inner surface of second or third rib below. Extent: Confined to post. Part of the lower spaces only Direction of fibres: Same as innermost intercostal.
- 12. View ~~j;,c=:::::::::::....~ ~ ,....Tr:ansversus lfloracis ~em:;{ lntercoslal Internal intercostal Lateral View Serratus posterlor- -n:::v-~ r superior Serratus posterior--;-,,..______,.;;:;:;:;:~ inferior Posterior View _ .;.:,.._.,. External interoostal membrane Body of sternum Internal interoosllll Ribs: Levator costarum Anterior Innermost intercostal
- 13. Actions • Ext. intercostal-Inspiration, moves ribs superiorly • Int. intercostal- Expiration, moves ribs inferiorly • Innermost intercostal-Expiration • Subcostales – depress ribs • S.P.S elevates sup. 4 ribs, raising the sternum and AP diameter • S.P.I. depresses the inf. Ribs, so prevents then to be picked sup. By dia. • Transverse throcis • Lev. Costarum unimportant
- 14. Intercostal vessels • Each space has arteries arranged in two groups – Anterior(2) & posterior (1) • Veins also correspond to arteries & are arranged in two groups – Anterior(2) & posterior(1) • Intercostal nerves are 11 in no. on each side & are the ventral ramus of thoracic nerve
- 15. Intercostal Arteries Post intercostal artery • 11 on each side • One in each space • 1,2 – from superior IC artery (branch of costo-cervical trunk of subclavian • 3 – 11 – from descending thoracic aorta (Aortic intercostal arteries of Rt. Side are longer)
- 17. Anterior ramus Transverse process ] of thoracic nerve Superior costotransverse ligament Radiate ligament of head of rib Subcostal1----,-,= Anterior longitudinal ligament sels and nerve inches of intercostal vessels and nerve Communicating branches / (rami communicantes) ~Splanchnic nerve Anterior View Sympathetic trunk
- 18. Post. Intercostal artery Course Rt. Post IC artery arise from back of aorta Pass backward & laterally in front of Vertebral column & behind oesophagus , thoracic duct & azygos vein & sympathetic trunk Left passes behind Hemiazygos vein & sympathetic trunk In the Space Accompanied by vein & nerve VAN – from above down wards
- 20. Post. Intercostal artery • Each artery passes upward & laterally toward angle of upper rib • Run along the costal groove between 2nd & 3rd layer • Give a collateral branch at angle of rib &main branch continue & anastomose with upper anterior intercostal artery & collateral with lower ant. IC artery at costochondral junction
- 21. Anterior Intercostal artery • Present in all spaces except last two which are open in front 1-6 arise from internal thoracic artery 7-9 from musculophrenic artery Each space has two (upper & lower)
- 22. Venous drainage • Ant.IC Veins (upper 6 space) – internal thoracic V • Rest in musculophrenic vein • Post. IC Vein – one in each space Ist IC space – On Rt. & Lt.brachiocephalic vein 2nd , 3rd & 4th IC space –Form Rt. superior IC vein which drain in Azygos vein On left side form Lt superioor IC vein which drain in Lt brachiocephalic V 5th to 11th (Right) azygos vein 5th to 8th (Left) acc. Hemiazygos 9th to 11th (Left) hemiazygos 12th – subcostal vein
- 23. Typical TI1oracic SpiI1al Ne1,.,.re
- 24. branch Transversus thoracis Internal thoracic artery Lateral branch "' Rami communicantes Sympathetic ganglion Pleura Superior costotransverse ligament Posterior intercostal membrane Subcostalis ~...,,,..t-t-- lntercostal nerve External intercostal (ventral ramus) cutaneous branch Innermost intercostal Anterior cutaneous branch Medial Dorsal ramus