recursal/Fanatic-Fandom huggingface dataset:
Muscle/Group:Forearm: Deep fasciaFlexor Retinaculum

The **flexor retinaculum** is a rectangular-shaped fibrous band located at the ventral aspect of wrist.

On the radial side, it attaches to the scaphoid tubercle and the ridge of the trapezium. On the ulnar side, it attaches to the pisiform and the hook of the hamate.

The flexor retinaculum is the roof of and encloses the carpal tunnel. The ulna aspect of the flexor retinaculum forms the floor of Guyon's canal.

Attachments

* proximally: deep fascia of the forearm
* distally: palmar aponeurosis
* Hypothenar & thenar musculature arise from FR

Relations

* inferiorly: contents of the carpal tunnel
* superiorly
	+ ulnar artery and nerve (in Guyon's canal)
	+ palmar cutaneous branch of the median and ulnar nerves
	+ palmaris longus tendon
	+ superficial palmar branch of the radial artery

Variant anatomy

* radial aspect of the flexor retinaculum may be pierced by the median nerve

Clinical significance:

 In carpal tunnel syndrome, inflammation of one of the nine tendons causing compression of the median nerve in a tight non-flexible flexor retinaculum with pain and tingling of the tips of the hand. The palm is spared due to a palmar branch of the median nerve not tranversing the carpal tunnnel. Carpal tunnel release typically divides FR ulnarly near hook of hamate attachment
1. Bones

Normally 33 spinal vertebrae (varies from 32-35)

* 7 cervical (most constant); 12 thoracic; 5 lumbar
* 5 sacral elements fuse → sacrum
* 4-5 coccygeal elements → coccyx (most variable)

Classic anatomic division into anterior (vertebral body), posterior elements (neural arch)

"Three columns" concept

* Anterior column
	+ Anterior half of vertebral body/disc/annulus
	+ ALL
* Middle column
	+ Posterior half of vertebral body/disc/annulus
	+ PLL
* Posterior column
	+ Posterior elements (pedicles, facet joints, laminae, spinous processes)
	+ Ligamentum flavum
	+ Interconnecting ligaments (interspinous, etc.)

Bones

* Body: Cylindrical ventral bone mass
* Arch: Composed of 2 pedicles, 2 laminae, 7 processes (1 spinous, 2 transverse, 4 articular)
	+ Pedicles: Extend from dorsolateral body to unite with pair of arched, flat laminae
	+ Laminae: Arch over canal, join at midline to dorsal projection (spinous process)
	+ Transverse processes: Arise from sides of arch
	+ Articular processes: Each has superior process (with facet directed dorsally), inferior process (facet directed ventrally), pars interarticularis (between facets)

* Intervertebral disc
	+ Composed of inner nucleus pulposus, outer annulus fibrosus
	+ Adhere to hyaline cartilage of vertebral endplates
	+ Avascular (except in young children and peripheral annular fibers in adults)

Ligaments

* ALL
	+ Fibrous band along entire ventral surface of spine
	+ Skull to sacrum
* PLL
	+ Dorsal surface of vertebral bodies
	+ Skull to sacrum
* Craniocervical ligaments
* Interspinous ligaments

Nerves (31 pairs)

* 8 cervical, 12 thoracic
* 5 lumbar (exit above disc, below pedicle)
* 5 sacral, 1 coccygeal

Meninges

* Single (meningeal) layer of dura
* Arachnoid (continuous with cranial arachnoid, loosely adherent to dura)
* Pia (covers spinal cord, nerves)

Vasculature

* Arteries: Segmental arteries arise as dorsal rami from vertebral, subclavian, intercostal arteries
* Veins: Y-shaped basivertebral veins connect with valveless epidural venous plexus; extensive anastomoses with cavae, azygos/hemiazygos systems
Muscle/Group:Forearm:Flexor compartment superficial layer:Pronator teres

The most lateral of the superficial forearm flexor compartment. Medial nerve lies between the two heads and ulnar artery pass deep to the deep head. The muscle run distally across the front of the forearm.

Origin: common origin from the lower part of the medial supracondylar ridge (smaller head from the coronoid process of the ulnar)

Insertion:middle of the lateral surface of the shaft of the radius

Nerve: muscular branch of the median nerve
Anatomy of the Thorax

Anatomy

Sternum
Typical thoracic vertebral bodies
Scapula  | Clavicle
Manubriosternal joint  | Costochondral joint
Ligamentum arteriosum  | Central tendon of the diaphragm   | Pulmonary ligament
Intercostal muscles
Pectoral muscles
Serratus muscle, anterior  | Scapular muscles
Brachiocephalic artery
Common carotid arteries
Subclavian arteries
Pulmonary arteries
Bronchial arteries
Right and left internal mammary arteries
Coronary arteries
Intercostal arteries, posterior and anterior  | Thyrocervical trunk
Costocervical trunk  | Lateral thoracic artery
Dorsal scapular artery
Brachiocephalic veins
Subclavian veins
Azygous vein
Hemiazygous vein
Pulmonary veins
Coronary veins  | Accessory hemiazygous vein
Superior and supreme intercostal veins
Lateral thoracic vein  | Internal mammary veins
Phrenic nerve
Spinal cord  | Intercostal nerves
Trachea
Heart
Muscle/Group:Shoulder (Pectoral):Pectoralis minor

**Pectoralis minor**is a muscle of the anterior chest wall that inserts into the pectoral girdle. It lies deep to and is completely covered by pectoralis major.

It is an important anatomical landmark in the division of the axillary artery as well as in the distribution of axillary lymph nodes.

* **origin** - ribs 3-5
* **insertion** - coracoid process of the scapula
* **innervation** - medial and lateral pectoral nerve
* **action**
	+ depresses shoulder
	+ when scapula fixed, elevation of ribs 3-5
Abdomen:Venous:Portal system

**Portal vein** **(PV)**is the main vessel in the portal venous system and drains blood from the gastrointestinal tract and spleen to the liver. The portal vein, usually measures approximately 8 cm in adults

Origin: behind the neck of the pancreas and is usually formed by the confluence of the superior mesenteric and splenic veins

Course:

* It runs vertically upwards in the free edge of the lesser omentum, lying behind the bile duct and hepatic artery.
* Immediately before reaching the liver, the portal vein divides into left portal vein (supplying liver segments II, III, IV) and the right portal vein.
* This subsequently divides further into anterior (supplying liver segments V and VIII) and posterior (supplying liver segments VI and VII) portal veins .
* Left branch receives ligamentum teres - obliterated umbilical vein.
* It ramifies further, forming smaller venous branches and ultimately portal venules.

Relations:

* Posterior: IVC
* Anterior: pancreas and D1 of duodenum.

Each portal venule courses alongside a hepatic arteriole and the two vessels form the vascular components of the portal triad. These vessels ultimately empty into the hepatic sinusoids to supply blood to the liver.

75% of the blood supplied to the liver comes from the portal vein, but it only supplies 50% of the oxygen supply to the liver.

#### Variant anatomy

The overall incidence of portal vein variation is reported to be 25-30%. There is an increased risk of bile duct hilar anatomical variation in the presence of portal vein variants. These anatomical variants should be recognized prior to procedures such as liver transplantation, complex hepatectomy and portal vein embolisation.

Portal vein trifurcation: this is the most common variant. The portal vein divides into three branches; the left portal vein, the right anterior portal vein, the right posterior portal vein.

Right posterior portal vein splits off as the first branch of the portal vein. The right anterior and the left portal veins then originate from a common trunk.

Tributaries:

* Lower third of oesophagus drain into oesophageal veins, to the **left gatric vein**. Upper third drain into the azygos vein. The left gastric, pass along the lesser curvature, in the posterior wall to join the portal vein.
* **Right gastric** run along lesser curvature to the pylorus and enter the portal vein.
* **Short gastric and left gastroepiploic vein** run with arteries to the hilum and spleen and empty into the splenic vein. **The splenic vein** travel with the tail of the pancreas below the splenic artery, in the splenorenal ligament and continues to the right, posterior to the body of the pancreas, lying on the hilum of kidney, left psoas muscle, left sympathetic trunk, left crus of the diaphragm, aorta, SMA, and IVC to terminate in the portal vein. At the left crus it receives the inferior mesenteric vein.
* The **right gastroepiploic vein** join the SMV at the lower border of the neck of the pancreas.
* **Cystic vein** join the right branch of the portal vein.
* **Paraumbilical veins** running with the ligamentum teres join the left branch.
Globe & Contents

Segments

* Anterior segment of globe
	+ Portion of eye in front of anterior margin of vitreous (hyaloid face)
		- Ciliary body, suspensory ligaments and lens
		- Anterior and posterior chambers
		- Iris
		- Cornea
* Posterior segment of globe
	+ Vitreoretinal portion of the eye and its layers
		- Vitreous chamber
		- Retina
		- Choroid
		- Sclera

Chambers

* Anterior chamber
	+ Major chamber of anterior segment
	+ Between cornea and iris
	+ Filled with aqueous humor which provides nutrition and structure
* Posterior chamber
	+ Small potential space posterior to iris and anterior to lens/ligament complex
	+ Contiguous with anterior chamber through pupil
* Vitreous chamber
	+ Large chamber that fills posterior segment
	+ Filled with viscoelastic transparent gel

* Tunicae
	+ Tunica interna (retina)
		- Multilayered sensorineural organ
			* Photoreceptor cells (rods and cones) overlie pigment epithelium at outermost layer
			* Bipolar and ganglion cells form inner layer (next to vitreous), & assemble & convey sensory signals
		- Regions and extent
			* Macula: Central portion, daylight & color vision
			* Fovea: Macular center, highest spatial resolution
			* Peripheral: Outer portion, night vision & motion
			* Ora serrata: Anterior margin of retina
	+ Tunica vasculosa (uvea)
		- Pigmented, vascular loose connective tissue
		- Choroid
			* Layer between retina and sclera
			* Vascular supply to photoreceptor layer
		- Ciliary body
			* Uveal structure anterior to ora serrata
			* Attached to lens via zonule fibers
			* Contractile function provides for lens accommodation
			* Source of aqueous production
		- Iris
			* Thin elastic tissue overlying lens
			* Sphincter muscle provides pupillary response
	+ Tunica fibrosa (sclera)
		- Outer fibrous layer
		- Attachment site for extraocular muscles
		- Contiguous with dura of optic sheath as well as fibrous diaphragm (lamina cribrosa) at nerve head
		- Contiguous with cornea anteriorly
Abdomen:Nerves:Lumbar nerves and plexus

**Lumbar plexuses**

Formed from the anterior rami of the upper four lumbar spina nerve wihin the substance of the psoas muscle. These first supply the psoas and quadratus lumborum then divide into anterior and posterior divisions.

The lumbar lexuses supply the lower lumbs(L2-L4) and the lower anterior abdominal wall (L1), sensory branches to the parietal peritoneum

Branches:

* **Iliohypogastric/Ilioinguinal (anterior):** these two branches are segmental body wall nerves in series with the thoracic nerve and do no fully participate in the plexuses. They supply skin over inguinal region, front of scrotum, and motor supply for the internal oblique and transversus that form the roof of the inguinal canal to the conjoint tendon.
	+ Iliohypogastric n: Traverses internal oblique m. anterior to ASIS, traverses external oblique m. above superficial inguinal ring
	+ Ilioinguinal n: Traverses internal oblique m. adjacent to deep inguinal ring, courses through inguinal canal
* **Genitofemoral (anterior):** has two parts - femora (supply area of skin below the middle inguinal ligament) and genital (abdominal derivatives in the genitals, e.g. spermatic cord).
* **Lateral femoral cutaneous (posterior):** sensory nerve. It emerges from lateral border of psoas and enter the thigh by passing through and under the lateral part of the inguinal ligament. It supplies the iliac fascia and peritoneum of the iliac fossa and lateral of the thigh.
* **Femoral (posterior):** the nerve pass from the lateral border of psoas and crosses the iliac fossa in the gutter between psoas and iliacus, and pass beneath the inguinal ligament lateral to the femoral sheath. It divides into several branches:
	+ main branch supplies the iliacus
	+ nerve to pectineus: runs behind femoral sheath to the muscle
	+ nerve to sartorius: pierce the muscle and continue as intermediate femoral cutaenous nerve
	+ medial femoral cutaneous nerve: supplies the medial side of the thigh and anterior branch reaches the front of the knee.
	+ nerve to rectus femoris: double, with the upper branch supplying the hip joint.
	+ nerve to vastus lateralis - pass down with descending brnach of the lateral feoraml circumflex artery between rectus femoris and vastus intermedis
	+ nerve to vastus intermedius - enter the upper part of the subsartorial canal and sinks into the muscle.
	+ saphenous nerve: terminal branch - crosses the femoral artery and emerge behind the posterir border of the sartorius. It pierces the fascia lata between sartorius and gracilis and descends to skin over the tibia.

All three vasti muscle supply the knee joint.

* **Obturator (anterior):** medial to the psoas, lies on the ala of sacrum, between the angle of the external and internal iliac vessels, it runs through the obturator foramen and divide into anterior and posterior branches (demarcated by adductor brevis).
	+ Posterior branch supplies obturator externus and runs down on adductor magnus and accompanies the femoral artery into popliteal fossa.
	+ Anterior branch runs deep to pectineus/adductor longus and supplies the medial compartment.
National CrowdFunding Bank Account

Bureaucracy is inefficient. Bureaucrats usually are not the best experts in the field to make the decisions they have to make. Bureaucrats decide where the tax payers money go. Could it be that the time has come to automate their jobs?

Governments give all kind of subsidies for different reasons and for different businesses. This money is allocated in the budgets. Instead of filling the application papers for regular government subsidies, it would be more effective if the business would have to create a CrowdFunding project:

* This way, the business would have to market their ideas for the customers before the subsidies.
* If customers would be CrowdFunding an idea it is a strong signal for the government that this business deserves to get subsidies.
* The discussion around the CrowdFunding could lure in some experts, important contacts and people who can market the ideas.
* People should have control and say about where the government is investing!

The Minimum Viable Product to test the idea could be that government would host CrowdFunding projects and would give grants for the most successful ones. Later this idea could be expanded towards a system, where every Finnish citizen would have their own CrowdFunding accounts, which they could invest to government approved CrowdFunding projects (minor legistlation might be required, not sure though, minimal approach is important).

**This page is not-protected, plese feel free to edit this page if you have ideas!**

**The status of this article is first-draft; if you find these ideas useful, give me feedback and help me improve the reading experience for the next reader.**
Arterial structure:AxillarySubscapular artery

The **subscapular artery** is the largest branch of the axillary artery.

The subscapular artery originates from the  medial surface of the third-part of theaxillary artery. It passes along the inferior border of the subscapularis muscle and it divides into two branches

1. **Thoracodorsal artery**: courses downwards along the serratus anterior muscle and posterior to the lateral thoracic artery supplying the intercostal muscles, serratus anterior and lattismus dorsi muscles as well as the skin of the lateral surface of the thorax.
2. **Circumflex scapular artery** (scapular circumflex artery, dorsalis scapulae artery): divides into three branches to supply the pectoral girdle.

Supply

* subscapularis, supraspinatus and infraspinatus muscles
* latissimus dorsi muscle
* serratus anterior muscle

Variant anatomy

The subscapular artery is quite stable with ~85% demonstrating classical anatomy as described above

* arises from second-part of axillary artery (~15%)
* absent in ~3% - thoracodorsal and circumflex scapular arteries arise separately from the axillary artery
* posterior humeral circumflex artery arising from the subscapular or thoracodorsal arteries
* lateral thoracic artery arising from the subscapular artery
Bone:Clavicle, scapula and humerus:Articular surfaces

CLAVICLE

At the sternal end, there is a facet for the articulation with the sternum and the first costal cartilage.

At the acromion end, there is facet which faces laterally and downwards for articulation with acromion.

SCAPULA:

Acromion articulate with the clavicle

The glenoid fossa articulate with head of the humerus
Abdomen:Solid viscus:Suprarenal glands

The **adrenal (suprarenal) glands** lie antesuperior to the kidneys. They are paired organs of the endocrine system with a cortex and medulla. Both adrenals are quite asymmetric in shape.

Each gland is enclosed in the perirenal fascia and each have a body and two limbs -medial and lateral. However, the right adrenal gland is pyramidal in shape while the left adrenal gland is crescenteric.

The adrenal gland weighs on average 4-6g and measures 4-6cm long and 2-3cm wide. Each limb normally measures ≤ 5mm in width and the body should measure ≤ 8-10mm in width.

The adrenal gland has a thick outer cortex and a thin inner medulla surrounded by a fibrous capsule

Relations: located at the level of L1.

Right adrenal gland

* medial: right inferior phrenic artery, vertebral column
* lateral: right lobe (bare area) of the liver
* anterior: inferior vena cava (IVC)
* posterior: right kidney, right crus of the diaphragm
* inferior: right kidney

Left adrenal gland

* medial: left inferior phrenic artery, vertebral column
* anteromedial: diaphragm
* anterior: lesser sac, stomach, splenic artery, pancreas
* posterior: left kidney, left crus of the diaphragm
* inferior: left kidney

Blood supply

* arterial supply
	+ superior suprarenal artery (from inferior phrenic artery)
	+ middle suprarenal artery (from abdominal aorta)
	+ inferior suprarenal artery (from renal artery)
* venous drainage: does not run with the artery.
	+ suprarenal veins drain emerge from the hilum and drain to
		- left renal vein (left adrenal gland)
		- IVC (right adrenal gland)

Nerve supply

* plexus formed at the medial border of the gland
* sympathetic from splanchnic nerves (T5-T9) via the coeliac and renal plexuses
* Presynaptic sympathetic fibres form paravertebral ganglion to medulla

Lymphatic drainage

* lymphatics are contained within the capsule and drain para-aortic nodes and coeliac nodes.

Variant anatomy

* horseshoe adrenal gland
* pancake adrenal gland
	+ takes on a flattened appearance
	+ often in the presence of a pelvic kidney or renal agenesis
* adrenal gland hypoplasia/agenesis
* accessory adrenal nests
	+ often near adrenal glands but may be found anywhere in the abdomen, pelvis or scrotum
Muscle/Group:Shoulder (Pectoral):Supraspinatus

**Supraspinatus muscle**

* Origin: Supraspinatus fossa of scapula
* Insertion: Superior facet (horizontal orientation) and portion of middle facet of greater tuberosity
* Nerve supply: Suprascapular nerve
* Blood supply: Suprascapular artery (off thyrocervical) and circumflex scapular branches of subscapular artery
* Action: Abduction of humerus
* Anterior and posterior muscle bellies
	+ Anterior belly is larger, has central tendon and is more likely to tear
	+ Posterior belly is strap-like & has terminal tendon
* Most commonly injured rotator cuff muscle
Larynx:Intrinsic muscles

**Transverse arytenoid:** attach opposite posterior surface of the arytenoid cartilage. It draws arythenoid nearer to each other and adduct the vocal folds.

**Oblique arytenoid:** pass from muscular process of one to the apex of the opposite arytenoid. Crosses each other on the posterior surface of the transverse arythenoid. It has the same action as the transverse. Some fibres continue from the arytenoid to the epiglottis which is the aryepiglottic muscle.

**Posterior cricoarytenoid:** arise from concavity on the back of the cricoid lamina, and pass to the back of the muscular process of the arytenoid. It moves the artenoid laterally and rotate the vocal process outside thus opening the vocal folds.

**Lateral cricoarytenoid:** arise from the upper border of the cricoid arch and pass upwards and back to the muscular process of thearythenoid. Drwas the msucular process fowards and rates the vocal process inwards and closes the glottis.

**Thyroarytenoid:** extends backwards and laterlly from the angle of the thyroid to the anterolateral surface of the arytenoid and lateral surface of its vocal proess. It shortens and relaxes the vocal ligament thereby altering the pitch of the voice. Part of the muscle fibres arise from the vocal ligament, and form the vocalis muscle.

**Thyroepiglottic muscle:** thyroarytenoid fibres that pass up to the aryeglottic fold and open the laryngal inlet by abductig the aryepiglottic fold.

**Cricothyroid:** fan shaped muscle on the outer surface of the larynx, and arise from the lateral aspect of the cricoid arch and attach to the inferior horn of the thyroid lamina. Contraction tilt the thyroid forward, and lengthen the vocal ligament.
Deep DCF:Perivertebral space

The **perivertebral space** is one of the deep compartments of the head and neck.

The perivertebral space is a cylinder of soft tissue lying posterior to the retropharyngeal space and danger space surrounded by the deep cervical fascia and extends from the skull base to the upper mediastinum.

The deep fascia sends a deep slip to the to the transverse process which subdivides the space into:

* **prevertebral portion**: located anterior to transverse process
* **paraspinal portion**: located posterior to transverse process

Contents

* prevertebral portion
	+ cervical vertebral body and disc
	+ prevertebral muscles
	+ scalene muscles
	+ vertebral artery and vein
	+ phrenic nerve
	+ brachial plexus (proximal aspect)
* paraspinal portion
	+ posterior elements of cervical vertebrae
	+ paraspinal muscles
	+ levator scapulae

Boundaries

* anterior: danger space and retropharyngeal space
* posterior: fascia attaches to spinous process and ligamentum nuchae
* lateral: surrounded by posterior cervical space
* superior: base of skull
* inferior: the perivertebral space is usually defined from the skull base to superior mediastinum (clavicles) but can be extended to the level of the coccyx
Abdomen:Radiological spaces:Renal fasciae and spaces

The **retroperitoneum** is the part of the abdominal cavity that lies between the posterior parietal peritoneum and anterior to the transversalis fascia.

It is divided into three spaces by the perirenal fascia. These are dense, elastic connective tissue sheath that envelops each kidney and adrenal gland together with a layer of surrounding perirenal fat.

The fascia is a multi-laminated structure which is fused posteromedially with the muscular fascia of the psoas and quadratus lumborum muscles. It extends anterolaterally toward the kidney as a bileaved layer, which then divides into two perirenal fasciae that surrounds it.

* **Gerota fascia:** a thin lamina that passes around the front of the kidney and variably interweaves with the opposite anterior fascia
* **Zuckerkandl fascia:**a thicker posterior fascia which continues anterolaterally as the lateroconal fascia and fuses with the parietal peritoneum
* These fascia planes can be called interfascial planes, and communicate at the juncture of the lateroconal and renal fascia. They communicate across the abdominal midline.

The three retroperitoneal spaces are:

* **anterior pararenal space**
* **perirenal space:** the largest of the three areas in the retroperitoneum.
	+ Content: kidneys, renal vessels and proximal collecting systems, adrenal glands and fat.
	+ Relations: The space is surrounded by the perirenal fascia.
	+ It abuts the bare area of the liver on the right and the subphrenic space on the left; there is mediastinal communication via the various diaphragmatic hiatus. The space is usually closed inferiorly, preventing pelvic spread of infection.
* **posterior pararenal space:** smallest portion of the retroperitoneum.
	+ Content: fat, blood vessels and lymphatics, but contains no major organs.
	+ Relations: posteriorly bound by transversalis fascia, anteriorly bound by posterior perirenal fascia (Zackerandl's fascia), medially bound by fusion of the posterior perirenal and transversalis fasciae with muscular fasciae, cranial extent is determined by the fusion of psoas and quadratus lumborum with the inferior phrenic fascia and inferiorly opens into the pelvis.

A fourth space, the great vessel space, is defined in the recent literature but perhaps not considered one of the three classically described spaces above.
Cranial nerve systems:Vestibulocochlear nerve & spiral ganglion

Sensory nerve originating from the pons, consisting of two parts

* Vestibular part: Balance
* Cochlear part: Hearing

Cochlear Nerve

* Origin: the spiral ganglion within modiolus of cochlea
	+ Peripheral fibers pass to organ of Corti in cochlear duct (scala media) within cochlea
	+ Central fibers coalesce & pass as auditory component of CN8 (cochlear nerve) to brainstem
* Course:
	+ pass from modiolus through cochlear aperture into internal auditory canal (IAC)
	+ Cochlear nerve joins together with superior & inferior vestibular nerves to form vestibulocochlear nerve (CN8)

Vestibular Nerve

* Origin: vestibular (Scarpa) ganglion located within vestibular nerve in fundal portion of IAC
	+ Peripheral fibers pass to sensory epithelium of utricle, saccule & semicircular canals
		- Traverse multiple foramina in cribriform plate in lateral wall of IAC fundus
	+ Central fibers coalesce to form superior & inferior vestibular nerves that pass medially to brainstem
* Course:
	+ Superior & inferior vestibular nerves pass medially from IAC fundus and joins the cochlear nerve to form vestibulocochlear nerve (CN8).

Vestibulocochlear nerve

* crosses CPA cistern posterior to facial nerve
* Enters lateral brainstem at junction pons & medulla
* Cochlear nerve fibers bifurcate, ending in dorsal & ventral cochlear nuclei
	+ Cochlear nuclei found on lateral surface of inferior cerebellar peduncle (restiform body)
* Vestibular nerve fibers divide into ascending & descending branches which mainly terminate in vestibular nuclear complex
	+ Vestibular nuclear complex
		- Four nuclei (lateral, superior, medial & inferior)
		- Located beneath lateral recess along floor of fourth ventricle (rhomboid fossa) in lower pons
		- Complex connections exist between vestibular nuclei, cerebellum, spinal cord (vestibulospinal tract) & nuclei controlling eye movement
Muscle/Group:Shoulder (Pectoral):Subscapularis

**Subscapularis muscle**

* Origin: Subscapular fossa of scapula
* Insertion: Lesser tuberosity and up to 40% may insert at surgical neck
* Nerve supply: Subscapular nerve, upper and lower
* Blood supply: Subscapularis artery
* Action: Internal rotation of humerus, also adduction, extension, depression and flexion
* 4-6 tendon slips converge into main tendon; multipennate morphology increases strength
Abdomen:Visceral arteries:Gonadals

The **gonadal arteries** arise from the front of the aorta, below the renal arteries but above the IMA.

* They slope downwards over the psoas and genitofemoral nerve and crossing the ureter.
* The left artery crossed by IMV. The right is crossed by the duodenum and root of the mesentery. Both reach the pelvic brim.
* The testicular artery run along the pelvic brim above the external iliac artery and enters the deep inguinal ring.
* The ovarian artery crosses the pelvic brim and the external iliac vessels and enters the suspensory ligament
Arterial structures:Pelvis:Obturator artery

The **obturator artery** is a anterior branch of the internal iliac artery that passes antero-inferiorly on the lateral wall of the pelvis, to the upper part of the obturator foramen, and, escaping from the pelvic cavity through the obturator foramen. It divides into both an anterior and a posterior branch.

Relations:

* Laterally, the obturator fascia
* Medially, the ureter, ductus deferens, and peritoneum
* Inferiorly: obturator nerve.

Branches:

Inside the pelvis the obturator artery gives off

* Iliac branches to the iliac fossa, which supply the bone and the Iliacus, and anastomose with the ilio-lumbar artery
* Vesical branch, which runs backward to supply the bladder; and
* Pubic branch ascends upon the back of the pubis, communicating with similar artery of the opposite side, and the inferior epigastric artery.

After passing through the obturator foramen, the artery divides at the upper margin of the obturator foramen, into an anterior branch and a posterior branch.

* The **anterior branch** is a small artery in the thigh, curves downward along the anterior margin of the obturator foramen. It distributes branches to the obturator externus, pectineus, adductors, and gracilis muscle, and anastomoses with the posterior branch and with the medial femoral circumflex artery.
* The **posterior branch** is a small artery in the thigh and follows the posterior margin of the foramen and turns forward on the inferior ramus of the ischium, where it anastomoses with the anterior branch.

Normal variant

Origin from:

* post division of internal iliac
* SGA
* EIA
* Replaced by pubic branch of inferior epigastric artery
Anatomy of the Abdomen

Anatomy

Parietal branches
Common iliacs
Common hepatic
SMA
IMA
Renals  | Adrenals
Gonadals
Splenic
Genital  | Duodenal
Pancreatic
Gastric
Lesser sac
Right mesenteric space
Left mesenteric space
Supramesocolic
Inframesocolic
Right and left paracolic
Inguinal canal
Thoracoabdominal and subcostal nerves in abdominal wall
Sympathetic trunk and ganglia  | Greater, lesser, least splanchnics
Stomach
Duodenum
Jejunum
Ileum
Caecum
Appendix
Colon
Renal pelves and ureters
Gallbladder
IVC and tributaries
Portal system
Portosystemic anastomoses  | Gonadal veins
Anterolateral abdominal muscles and aponeuroses
Paraaortic nodes
Preaortic nodes
Portal, portocaval nodes
Peripancreatic nodes
*Couinaud segments*
*Venous anatomy*
Spleen
Suprarenal glands
Kidneys
Pancreas
Muscle/Group:Shoulder (Pectoral):Teres minor

Teres minor muscle

* Origin: Lateral scapular border, middle half
* Insertion: Inferior facet (vertical orientation) of humerus greater tuberosity
* Nerve supply: Axillary nerve
* Blood supply: Posterior circumflex humeral artery & circumflex scapular branches of subscapular artery
* Action: External rotation of humerus
* Least commonly injured rotator cuff muscle
Facial bones:Maxilla

The **maxillae** bones are one of the facial bones, forming the upper jaw and palate of the mouth. The two halves are fused at the intermaxillary suture to form the upper jaw.

Each maxillae consists of:

* The body of the maxilla
* Four processes
	+ The zygomatic process
	+ The frontal process of maxilla (orbital and lateral wall of nasal cavity)
	+ The alveolar process: holds the upper teeth, and is referred to as the maxillary arch.
	+ The palatine process (floor of nasal cavity)
* Infraorbital foramen
* The maxillary sinus: a pyramid-shaped paranasal sinus which drains into the middle meatus of the nose. It is the largest of the paranasal sinuses.

Articulations: each maxilla articulates with nine bones:

* two of the cranium: the frontal and ethmoid
* seven of the face: the nasal, zygomatic, lacrimal, inferior nasal concha, palatine, vomer, and the adjacent fused maxilla.

Development: The maxilla is ossified from two centers only, one for the maxilla proper and one for the premaxilla.

These centers appear during the sixth week of fetal life and unite in the beginning of the third month, but the suture between the two portions persists on the palate until nearly middle life. Mall states that the frontal process is developed from both centers.

Each maxilla also enters into the formation of two fossae: the infratemporal and pterygopalatine, and two fissures, the inferior orbital and pterygomaxillary.

**Maxillary sinus**

The space with the body of the maxilla. This sinus is pyramidal in shape with the apex in the zygomatic process of the maxilla and base at the lateral wall of the nose.

- roof: floor of the orbit. A ridge projects downwards, houses the passage of the intraorbital nerve within its canal.

- floor: the alveolar process of the maxilla

- posterior wall - infratemporal and pterygopalatine fossae

- anterior wall: cheek

It is present at birth but as a slit on the medial side of the floor of the orbit, and it begin to develop until around the age of 14 years. The body of the neonatal maxilla lateral to this is full of developing teeth. The sinus increase in size, and after the second dentition, the floor of the sinus is level with the floor of the nose. Rapid growth of the sinus occurs after puberty.

Drainage: ostium of the sinus is superior and posterior on its medial wall. Its 2-4mm, and opens at the posteriior part of the infundibulum in the middle meatus of the lateral wall of the nose. An accessory ostium may open anterior to posterior to the lower part of the uncinate process

Blood supply:

- arterial: small arteries from the facial, maxillary, infraoribtal and greater palatine

- venous: accompany arteries to the facial vein and pterygoid plexus

Lymph drainage:

- submandibular nodes

Nerve supply:

- infraorbital and superior alveolar branches of the maxillary nerve. The alveolar nerves run down to the teeth in the walls of the sinus, and these minute branches pierce the bone to supply the mucous membrane of the sinus.
Muscles:Anterior compartment of the thigh:Vastus lateralis

* Vastus lateralis
	+ O: Superior intertrochanteric line femur, anterior & inferior greater trochanter, gluteal tuberosity, lateral lip linea aspera, lateral intermuscular septum
	+ I: Lateral tibial condyle (lateral patellar retinaculum) superolateral patella (quadriceps tendon)
	+ Largest quadriceps muscle
Cranial vault: Bones:Occipital

The occipital bone is a trapezoid skull bone that contributes to the posteroinferior part of the cranial vault. It is pierced by the foramen magnum, permitting communication from the cranial cavity to the vertebral canal

#### Gross anatomy

The occipital bone is composed of four parts:

* squamous part: external/internal surfaces
* basilar part (basiocciput): lower/upper surfaces
* lateral (jugular) parts (two): under/upper surfaces

The squamous part is the curved, expanded plate located behind the foramen magnum.

The external surface of the squamous part features:

* external occipital protuberance
* highest nuchal line
* superior nuchal line: occipitalis, trapezius, sternocleidomastoid, splenius capitis
* inferior nuchal line: rectus capitis posterior major and minor
* median nuchal line: attachment of ligamentum nuchae
* attachment of posterior atlanto-occipital membrane

The internal surface of the squamous part features:

* cruciate eminence divide region into four fossa; the upper two contain the occipital lobes while the lower two contain the cerebellar hemispheres
* internal occipital tuberosity at intersection
* sagittal sulcus for superior sagittal sulcus, falx cerebri attaches to margins
* internal occipital crest gives attachment to falx cerebelli
* transverse grooves hold transverse sinuses

The basilar part is the quadrilateral piece in front of the foramen magnum.

The lower surface of the basilar part features:

* pharyngeal tubercle: attachment to fibrous raphe of pharynx
* either side of middle line: longus capitis, and rectus capitis anterior
* anterior atlanto-occipital membrane

The upper surface of the basilar part features:

* clivus has a broad, shallow groove, for medulla oblongata
* lateral grooves for the inferior petrosal sinus

The under surface of the lateral part features:

* occipital condyles: articulate with atlas, egg shaped, permitting nodding and lateral flexion, but not rotation
* hypoglossal canal: at base of occipital condyles
* condylar fossa: behind condyle, receives posterior margin of superior facet of atlas, can be perforated by condyloid canal which contains an emissary vein from the transverse sinus
* jugular process, excavated in front by jugular notch, forming posterior part of jugular foramen

The upper surface of the lateral part features

* jugular tubercle: overlies hypoglossal canal, sometimes crossed by oblique groove for CN 9, 10, 11

##### Articulations

The occipital bone articulates with 6 bones. Unpaired (one) bones include the sphenoid and atlas. Paired (two) bones include the parietals (lambdoid suture) and temporal (mastoid/petrous parts) bones.
Abdomen:Hollow viscus:Appendix

Appendix is a vermiform, vestigial blind ending tube that opens into the posteromedial wall of the caecum, approximately 2-3 cm inferiorly to the ileocaecal valve. Surface anatomy is the McBurney point.

The three taeniae of the caecuum, converges to form one complete longitudinal muscle for the appendix. It can vary in length from 2-20 cm.

The appendix lies on its own mesentery, the mesoappendix with a small fold of peritoneum (ileocaecal fold) extending from the teriminal ileum.

Location

The tip of the appendix can have a variable position within the abdominal cavity:

* retro-caecal (65-70%)
* pelvic (25-30%)
* pre- or post-ileal (5%)

Blood supply

* arterial: appendicular artery, a branch of the ileocolic artery, that pass behind the terminal ileum to enter to mesoappendix. This is an end artery, and it runs close to the appendicular wall, so in appendicitis, it can get thrombosed and cause ischaemic necrosis.
* venous: similarly named veins draining to the portal venous system

Nerve supply: Same as the caecum

* parasympathetic supply via pelvic splanchnic nerves (from S2 - S4)
* sympathetic supply via superior mesenteric plexus

Lymphatic supply

* from the caecum, lymph pass to the nodes associated with the ileocolic artery

Variant anatomy

* additional arterial supply from accessory appendicular artery
* duplex appendix: very rare
* retrocaecal appendix
* pelvic appendix
* asymptomatic appendicolith
Arterial:Femoral:Anterior tibial

The popliteal artery divides at the distal border of the popliteus muscle into the anterior and tibioperoneal trunk.

While still in the posterior compartment of the leg, the anterior tibial artery gives off the:

* recurrent posterior popliteal artery
* circumflex fibular artery

Subsequently it passes through a gap above the interosseous membrane into the anterior compartment of the leg. Here it lies on the interosseous membrane, lateral to tibialis anterior muscle.

The anterior tibial artery passes in front of the ankle joint and continues as the dorsalis pedis artery onto the dorsum of the foot lateral to the tendon of the extensor hallucis longus and medial to the extensor digitorum longus and deep peroneal nerve.

Branches

* anterior tibial recurrent artery: arises immediately, passes upward in the tibialis anterior muscle to anastomose with lateral genicular branches (of the popliteal artery) at the knee
* muscular branches
* perforating branches: pass behind extensor digitorum longus, piercing the deep fascia and supplying the skin of the anterior leg
* medial malleolar artery: anastomoses with medial malleolar branch of posterior tibial artery
* lateral malleolar artery: anastomoses with perforating branch of the peroneal artery
Grey matter nuclei (non-cranial nerve):Pineal gland

The **pineal gland** is a small, pine-cone shaped structure considered to be part of the epithalamus.

The pineal gland typically measures 7 x 6 x 3 mm in size and is situated in a groove between the laterally placed thalamic bodies in the quadrigeminal cistern.

Structure

* Attached to diencephalon & posterior wall of third ventricle by pineal stalk
* Pineal stalk consists of superior/inferior lamina (form superior & inferior borders of pineal recess of third ventricle)
* Superior/inferior lamina connect habenular/posterior commissures, respectively, to pineal gland

Relations

* anteriorly: third ventricle (pineal recess)
* posteroinferiorly: superior cerebellar cistern
* superiorly: internal cerebral veins, vein of Galen (posteriorly), stria medularis, splenium of the corpus callosum and velum interpositum
* inferiorly: superior colliculi of the midbrain

Vascular supply:

* Artery: medial posterior choroidal artery (lacks blood-brain barrier)
* Vein: drain into the great cerebral vein of Galen.

Functions:

* Secretion of melatonin, thought to regulate sleep/wake cycle in humans
* Regulation of reproductive function, such as onset of puberty in humans

Connections

* Habenular commissure: Connects habenular, amygdaloid nuclei and hippocampi
* Posterior commissure: Connections with dorsal thalamus, superior colliculi, pretectal nuclei and others; medial longitudinal fasciculus fibers also cross here
* Stria medullaris thalami: Fibers connecting both habenular nuclei
* Habenular nuclei: Relay station for olfactory centers, brain stem, and pineal
* Paraventricular nuclei: Connections with hypothalamus, hippocampus, amygdala, brain stem, septal nuclei and stria terminalis
* Superior cervical ganglia sympathetic fibers
* Dorsal tegmentum nonadrenergic tract
Meninges:Falx cerebelli

The **falx cerebelli**is a small infolding of the dura in the sagittal plane over the floor of the posterior cranial fossa. It partially separates the two cerebellar hemispheres.

The **falx cerebelli** is attached posteriorly in the midline to the internal occipital crest of the occipital bone where it contains the occipital sinus. Its anterior edge exists freely between the partially separated cerebellar hemispheres in the posterior cerebellar notch. Superiorly it is attached to the tentorium cerebelli. Inferiorly, it extends to the posterior edge of the foramen magnum. At this point it sometimes divides into two separate parts which extend anteriorly either side of the foramen magnum.

Relations

* anteriorly - cerebellum
* posteriorly - occipital bone
* inferiorly - foramen magnum
* superiorly - tentorium cerebelli

Variant anatomy

* duplication of the falx cerebelli
* absence of the falx cerebelli in Chiari II malformation (rare) 4
Abdomen:Lymphatics:Preaortic nodes

Pre-aortic nodes is situated at the origin of the coeliac, SMA and IMA branches and drains lymphatics of structures supplied by these, i.e. alimentary tract, liver, biliary tract, spleen and pancreas.

A small proportion of lymph passes retro-crurally to the medastinal nodes but the majority will form the intestinal lymph trunk and drain into the cisternal chyli.
Grey matter nuclei (non-cranial nerve)::Amygdala

**Amygdala:** large complex of gray nuclei medial to uncus, just in front of temporal horn of lateral ventricle. Tail of caudate nucleus ends in amygdala. Forms by three nuclei:

* basolateral
* corticomedial
* central group

Connections

Output fibres

The output fibers of the amygdala is mainly through two efferent fiber systems:

* stria terminalis
* ventral amygdalofugal pathway

The **stria terminalis** has a semicircular course in the body of the lateral ventricle. The level of the anterior commissure is a very important anatomical landmark because the stria terminalis splits into three parts:

* pre-commissural part
* commissural part
* post-commissural part

The pre-commissural fibers end in the septal region, and the post-commissural fibers end in the nucleus of stria terminalis. The commissural fibers connect the contralateral amygdala via the anterior commissure.

The **ventral amygdalofugal**pathway arises from the dorsomedial aspect of the amygdala, and courses medially through substantia innominata, anterior perforated substance, and fibers spread into the cerebral cortex, brainstem, mediodorsal thalamus, and hypothalamus. Direct efferent fibers project to the entorhinal cortex as well as the hippocampus 2.

Input fibres

The input fibers to the amygdalaare mainly represented by sensory fibers, which transfer information from numerous subcortical regions such as the hypothalamus, basal ganglia, septal region, and autonomic centers in the brainstem. Both the ventral amygdalofugal pathway and the stria terminals carry afferent and efferent fibers together. Some input fibers project to the amygdala along the olfactory stria, and directly from the temporal lobe.

Reciprocal fibres

The basal nucleus of Meynert, and the nucleus of the diagonal band project reciprocally to the amygdala along the ventral amygdalofugal pathway.
Arterial structure:Brachial:Brachial

**Brachial artery** is the continuation of the axillary artery.

Course:

- begins at the inferior margin of the teres major

- Gives off the deep artery of the arm proximally

- courses superficially in the arm, lying immediately deep to the deep fascia of the anteromedial aspect of the arm and between the biceps and the medial cutaneous nerve. Gives off the superior and inferior ulnar collaterals.

- passes in to the cubital fossa and divides into radial and ulnar arteries at the level of the neck of the radius.

Relations:

- the median nerve lies lateral proximally but crosses obliquely in front of the artery at the middle of the arm and lies medially at the distal arm.

- Located in the cubital fossa, medial to the biceps tendon and lateral to to median nerve, deep to the biceps aponeurosis

Branches

- deep artery of the arm: Descends posterolaterally with radial nerve, has branches anterior and posterior to lateral condyle forming an anastomosis

- superior ulnar collateral: arises medially and descends with ulnar nerve posterior to medial condyle, forms an anastomosis with branches of ulnar artery

- inferior ulnar collateral: arises distal to superior ulnar collateral artery, descends anterior to medial condyle, divides into anterior and posterior branches forming an anastomosis with branches of ulnar artery.
Intracranial cavity (extra axial): Posterior cranial fossa:Foramen magnum

The foramen magnum is the largest foramen of the skull and is part of the occipital bone 1. It is oval in shape with a large antero-posterior diameter.

The foramen magnum is found in the most inferior part of the posterior cranial fossa 3.  It is traversed by vital structures including the medulla oblongata 1.

##### Relations

* anteriorly - basilar part of occipital bone
* anterolaterally - occipital condyles, hypoglossal canal, jugular foramen
* posteriorly - squamous part of occipital bone with the internal occipital crest

##### Contents

* medulla oblongata
* meninges
* spinal root of the accessory nerve
* vertebral arteries
* anterior and posterior spinal arteries
* tectorial membrane and alar ligaments 2
Cerebral sulci:Parietooccipital fissure

Demarcate the boundary between occipital and parietal lobe (cuneus and precuneus respectively). Can be partially visualized on the lateral surface.

The medial part of the parieto-occipital sulcus runs downward and forward as a deep cleft on the medial surface of the hemisphere, and joins the calcarine fissure below and behind the posterior end of the corpus callosum.
7. Meninges

The **cerebral meninges** surround the brain and is made up of three layers (from outermost to innermost):

1. dura mater
2. arachnoid mater
3. pia mater

The dura mater can also be known as **pachymeninx**. The arachnoid mater and pia mater are collectively known as the **leptomeninges**3. The spinal meninges are similar but have some important differences.

The meninges function to protect the brain but also provides a framework for blood vessels, nerves, lymphatics and CSF 2.

There are two potential spaces:

* epidural (extradural) space - between the bone of the cranium and outer layer of the dura mater
* subdural space - between the two layers of the dura mater

There is one CSF-containing real space, subarachnoid space, between the arachnoid and pia mater.
Cerebral sulci:Lateral (Sylvian) fissure

The **Sylvian fissure**, also known as the **lateral sulcus**, separates the frontal and parietal lobes superiorly from the temporal lobe inferiorly. The insular cortex is located immediately internal to the Sylvian fissure. Region of the cerebral lobe that surround the lateral sulcus is the **opercula.**

 The middle cerebral artery and its major branches course laterally through the Sylvian fissure.