Tag: external abdominal oblique

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Anatomy Lesson: Sam’s Surface

Greetings all Anatomy Students!

What do I mean by Sam’s surface? I refer to his surface anatomy, also know as topographical anatomy. This branch of anatomy identifies structures from features expressed at the body surface. It does require anatomical knowledge by the user and is non-invasive. 

Over the years, I have received many images of Sam and Jamie from followers asking me to apply arrows and identify structures. This lesson is a compilation of some of these images. I hope you enjoy as much as I do. 😉

So, let’s get started!

Frontalis: Paired muscles of facial expression, frontalis fibers run vertically in the forehead. When they contract, they lift the brows and produce horizontal wrinkles of forehead skin, conveying concentration and concern. Perfect example from model Sam (blue arrows).

Corrugator Supercilii: Paired muscles of  facial expression from the nose side to the middle of each eyebrow. Upon contraction, corrugators draw the brows together and down producing small vertical wrinkles between the brows and a small bulge of skin above the brows. Jamie and Murtagh show  corrugator prowess (red arrows) as they watch the King of France during his a “private” moment (Outlander, episode 202 “Not in Scotland Anymore!” 😱

And, this image from outlander episode 708 “Turning Points,” shows an outstanding example of corrugator supercilii (red arrows) as Jamie realizes he almost shot his son during the second Battle of Saratoga! 🥺

Procerus: Procerus are muscles of facial expression wrinkling the skin over the bridge of the nose and flaring the nostrils. Results? They help create an expression of anger. “Who are you calling a procerus?” threatens Sam (red arrows). 😆

Supercilium: As everyone kens, eyebrows add to facial expression. Anatomically, the eyebrow is the supercilium (super silly, huh?). Sam has naturally thin, beautiful brows (purple arrow). I recall him being asked at during an interview if he plucked them, to which he responded, “Never.”

Vermilion Border: The vermillion border is intersection between facial skin and the rim of lips (turquoise arrow). Sam’s border forms a lovely Cupid’s Bow in the midline.

Moving on to the hands….

Metacarpophalangeal Joint: This joint (green arrow) is formed where the metacarpals of the palm meet the proximal phalange, the first and largest finger bone.

Proximal Interphalangeal Joint: This is the intersection between proximal phalange and middle phalange (red arrow).

Distal Interphalangeal Joint: This joint occurs between middle phalange and distal phalange (blue arrow).

Attention: The wonderful image below is the property of @KayZee. ❤️

Didn’t everyone notice Sam’s beautiful hands as he discusses Claire with Murtagh before the wedding in Outlander Episode 107, “The Wedding.” 😍

Moving on to the torso…

The next image is JAMMF between floggings – Outlander episode 106, “The Garrison Commander!” 😱 Lots of arrows on this one and the list is loooong but so worth it! 

Trapezius: Trapezius (red arrow) is  a massive flat triangular-shaped muscle that is paired. Together, they lift the shoulder joint and pull the shoulder joint back and down.

Clavicle: Commonly known as the collar bone (turquoise arrow), the paired clavicles are 6″ S-shaped bones between sternum and each shoulder joint. Clavicle is also the most commonly fractured bone of the body (one of my grandsons fractured his last year). It holds the shoulder joint away from the sternum allowing for greater mobility of the arm.

Fun Fact: Dogs and cats don’t have clavicles so their shoulder blades shift to lie at sides of the torso; ours lie over our backs. Thus, their front limbs move forward and back whereas, ours can rotate almost 360°. The human shoulder joint is the most movable joint of the human body, all because of the clavicle! 🤩

Sternocleidomastoid: Paired strap-like muscles (green arrow) joining sternum (breast bone) and clavicle to skull behind ear. Acting alone, each muscle flexes the neck toward the shoulder and rotates the chin toward the shoulder. Together, the muscles draw the chin toward the sternum.

Fun Fact: Sternocleidomastoid muscles are one of over  20 pair of muscles acting on the neck! 🤓

Suprasternal Notch: This bony landmark (purple arrow) indicates the top of the sternum. Intrathoracic pressure can be measured via the soft tissues above this landmark.

Sternum: The sternum (yellow arrow) is an unpaired bone which forms the front of the chest. It provides attachments for clavicles and first seven pair of ribs. It also supports and protects vital organs such as heart and lungs.

Rectus abdominis: This paired muscle (orange arrow) forms the belly on either side of the midline. Each muscle is long and flat, extending from sternum and ribs to pubic bone. Acting together, they bend head toward pelvis. 

Deltoid: The deltoid (white arrow) is shaped like an inverted triangle and overlies the shoulder joint, giving the shoulder its rounded contour. It helps raise the arm forward, to the side and backward. It is subdivided into anterior (front), middle, and posterior (back) sections.

Pectoralis Major: The term pectoralis is derived from the Latin meaning “breast.” Gyms refer to them as ‘pecs.” Pec major is paired and the largest muscle (black arrow) of the chest They draw the clavicle downward. They also raise the arm forward, pull arm against torso, or rotate arm toward sternum.

Biceps Brachii: The biceps (pink arrow) are the large muscles at the front of the arm. They create the fabulous bulge that Popeye made famous. In Latin, biceps means “two heads,” so named because the muscle originates from two different parts of the scapula. Biceps flexes the elbow joint and rotates the palm forward/upward. It also flexes the shoulder joint and draws the humerus (arm bone) against the torso.

Fun Fact: Contrary to popular opinion, biceps is not the prime mover of the elbow joint! A deeper lying muscle, brachialis, is the prime mover. 💪🏻

Latissimus Dorsi: Latissimus dorsi (aqua arrow) is a large flat muscle of the back. It inserts on the humerus pulling it backwards, against the body, and towards the sternum. Sam’s latissimus is massive! 🥳

and

The previous image of Sam as Jamie reminds me of “The Wound Man,” a surgical diagram that appeared in European medical texts of the fourteenth and fifteenth centuries, up until the 1700s. It showed various battle injuries and diseases that a medical practitioner might encounter. Cures were listed on nearby pages. A horrifying image, for sure! 😳

Next, Sam’s back is a marvelous roadmap of topographical anatomy.

Infraspinatus: This muscle (yellow arrows) extends from scapula (shoulder blade) to humerus (arm bone). It externally rotates and stabilizes the shoulder joint. Along with three other muscles, it helps form the rotator cuff of the shoulder joint.

Triceps Brachii: The triceps (orange arrow) derives its name from Latin meaning three heads because it takes origin from the scapula and two different areas of the humerus. It ends on a forearm bone, the ulna. It extends (straightens) the elbow joint.

Brachioradialis: This muscle (aqua arrow) attaches humerus to radius, a forearm bone. It helps flex the elbow joint.

Extensor Carpi Radialis Longus: This forearm muscle (violet arrow) reaches from humerus to second metacarpal bone. It extends (straightens) wrist and abducts hand (moves hand toward thumb).

Extensor Digitorum: Extensor digitorum lies next to extensor carpi radialis longus (blue arrow). It extends all four fingers (not thumb). Straighten your bent fingers. Extensor digitorum did that!

Extensor Carpi Ulnaris: This forearm muscle (green arrow) reaches from humerus to fifth metacarpal bone.  It extends the wrist and adducts the hand (moves hand away from thumb).

Posterior Deltoid: The deltoid  was explained above but now we add a caveat. Sam’s posterior deltoid (black arrow) is unusual because a distinct groove separates it from  middle deltoid (white star). Most people do not exhibit this distinct separation.

Erector Spinae: This massive muscle  (red arrow) is paired; it has several parts based on origin and insertion of the muscle fibers. Working together, erector spinae straightens the back; working alone, it rotates the back.

Next is Sam in a full plank position with elevated feet. This one has a number of repeated structures, but is still delightful to view. 🤩

Trapezius: Yellow arrow – see above

Deltoid: Blue arrow – see above

Pectoralis Major: Pink arrow – see above

Biceps Brachii: Violet arrow – see above

Latissimus Dorsi: Aqua arrow – see above

Rectus Abdominis: Orange arrow – see above

External Abdominal Oblique: The EAO is the largest flat abdominal muscle found at front and side of abdomen. It is also paired. It attaches to ribs above and pelvic bones below. Its fibers run from the sides downwards like your hands tucked into jean pockets. Acting alone, the EAO rotates the torso; acting together EAO pulls chest toward pelvis (as in curl ups). It also compresses the abdominal cavity. This muscle is important for posture and torso movements.

Brachioradialis:  red arrow- see above

Cephalic Vein: A vein of the arm – see below

This image of Sam in a sprint position is awesome because it shows:

Posterior Deltoid: Already described above, the white arrow indicates the unusual and distinct groove between middle deltoid and posterior deltoid.

Extensor Digitorum: Green arrow – see above

Extensor Digiti Minimi: This wee muscle (red arrow) isn’t prominent unless the forearm is highly muscular and subcutaneous fat is low. EDM reaches from humerus to wee finger and extends (lifts) it.

Some X followers already have seen my tweet of this image of Michelangelo’s “Moses” sculpture. But, for those who haven’t, it shows the master’s  attention to wee extensor digiti minimi! 🥰

Next is a full body view of Sam’s surface anatomy. This one shows a few arms veins that is a phlebotomist’s dream!

Just a note that venous pattern throughout the body is extremely varied so much so that hand vein patterns can be used to identify a person.

Median Antebrachial Vein: The median antebrachial vein (gold arrow) and its tributaries gather blood from hand and forearm and return it to the basilic vein (not shown).

Cephalic Vein: This large vein (red arrow) gathers blood from hand and forearm and returns it to a large vein (axillary vein) deep to the collar bone. Its name means “head” in Latin because its path through the arm points toward the head.

Deltopectoral Groove: Cephalic vein is traced through the deltopectoral groove (white arrow), a groove between anterior deltoid and pectoralis major muscles. 

Median Cubital Vein: This vein (orange arrow) located in the cubital fossa (elbow hollow) forms a bridge connecting cephalic and basilic veins.

Fun Fact: Median cubital vein is the preferred site for blood draws because it is large and doesn’t tend to roll or move when a needle is inserted. The area also has fewer pain endings.

Moving to the lower limb! 🤗

Just So You Know: Anatomists define the thigh as that part of the lower limb between hip and knee and the part between knee and foot is the leg.

Vastus Lateralis: Aptly named, vastus lateralis (blue arrow) is vast on Sam-our-Man! Vastus lateralis is part of the quadraceps group of four (some say five) thigh muscles. It arises from the femur and inserts on the patella. It then joins the other quad tendons to form a common tendon that inserts on the tibia (largest leg bone). It is the largest and most powerful muscle of the quadraceps group. Together with the other quadraceps muscles, it extends (straightens) the knee joint and keeps patella in proper alignment.

Fun Fact: The vastus lateralis is the recommended site for intramuscular injection of infants under 7 months old and those unable to walk or with loss of muscle tone and mass.

Vastus Medialis: Also a member of quadraceps, this muscle (black arrow) arises from the femur and inserts on the patella and then, tibia. It has the same function as vastus medialis (see above).

Patella: Also known as the knee cap, patella (purple arrow) is the largest sesamoid bone in the body, meaning it is enclosed in ligament or tendon.

Gastrocnemius: Gastrocnemius has two heads arising from different parts of the femur. These join together to help form Achilles tendon which inserts into the calcaneus (heel bone). Sam’s medial head (green arrow) is very apparent in this image. It is a powerful muscle that plantar flexes (points) the foot and flexes the knee joint.

Tibia: Tibia (violet arrow) is also known as the shin bone. It is the larger of the two leg bones. Together with the femur, tibia forms the knee joint and with the fibula (smaller leg bone), it forms the ankle joint.

Next is a famous image of Sam flipping kilt for the “girls” at Emerald City ComicCon, March 6, 2017.  Plenty of thigh muscle on display here! 😜

This amazing image is property of Marcia M Mueller. 👏🏻

Biceps Femoris: Biceps femoris (so named because it has two heads). The long head (red arrow) arises from the ischium (part of pelvic bone) and the short head (green arrow) arises from the femur (thigh bone). Both heads join into a single tendon that inserts on the fibula. Biceps femoris is a powerful flexor of the knee joint.

Not so Fun Fact: Avulsion (tearing away) of the biceps femoris tendon is common in sports that require explosive bending of the knee as seen with sprinting! 😱

Vastus Lateralis:  Blue arrow – See above

Quiz time!

Try to identify the structures in this last image of Sam. Do your best. Answers appear after the image. Good luck!

    • Orange arrow – sternocleidomastoid muscle
    • Violet arrow – pectoralis major muscle
    • Aqua arrow – Biceps brachii muscle
    • Green arrow – Vastus lateralis muscle
    • Red arrow –  Vastus medialis muscle
    • Blue arrow – medial head of gastrocnemius muscle
    • White arrow – Inguinal groove, (aka Adonis belt)  *** Extra credit for this one because we didn’t discuss! 😃

Well done, students! 🏆

The deeply grateful,

Outlander Anatomist

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Photo Creds: Sony/Starz; www.menshealth.com, www.thewrap.com, www.Wikimedia, @marciammueller, @samheughan, @kayzee

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Mini Anatomy Lesson: The Belly Wall

Anatomy Def: The belly wall is known by anatomists as the anterolateral abdominal wall (why use a simple word when a complex one will do?). 😉

Outlander Def: Claire’s Despair – Malva’s Mutilation! 😱

Before we begin this lesson, I have a true story to share…. In 2016, I asked Diana Gabaldon if nominative determinism was involved in her choice of Malva’s name because “mal” is the Latin word root meaning “evil” or “bad,” which clearly could apply here.

Why did I ask this? Think about it…. There’s mal-ware, mal-nutrition, mal-adapted, mal-content, mal-practice, mal-evolent, mal-odorous, and Mal-va! 😳

Diana answered, “No, I got it off a bottle of black malva shampoo!”

Haha. Love it! 😜

OK, anatomy students, let’s get on with our lesson.

Warning: The following images detail the final events of episode 606, “The World Turned Upside Down.” If you couldn’t watch this part of the episode, you might not want to read this lesson! 

Recap: Claire was in her surgery under the influence while someone “stomped through the nasties” with Malva. 

Never dreaming her beloved garden would be the site of a massacre, Claire spies Malva’s lifeless body, throat thoroughly mangled! 😯

Realizing her infant may still be alive, Claire springs into action, slicing open Malva’s gown with her garden knife.

Moving with speed and surety, Claire slices Malva’s belly wall vertically and to the left of her navel, a vertical cesarean section. 

Claire works ruthlessly with such intent and determination that Malva’s lifeless body shutters from her efforts.

Claire releases the infant from the womb and realizing its life is fleeting.  She performs mouth to mouth resuscitation and chest compression using two fingers. But, alas, her efforts fail.

Goodness, this is hard to review, even using still images.

After this episode was over, my husband, who is not a book reader, turned to me and asked, “Is that in the book?” ‘Yes,” I answered. He remarked, “That is going to be hard to explain.” 

He then added, “ Now, they have to figure out who murdered Malva.

”Who do you think it might be,” I asked. 

“Well, I would look to the brother, first,” he said.

Amazed, I asked “Why?” 

His answer: “Because in patriarchal systems, male relatives often kill women who bring shame upon their families.”  (See footnote at end of lesson) 😲 

‘Nuff said!

With this horrific scene as backdrop, let’s talk anatomy of the belly wall.

Abdominal Wall: The abdominal wall is a cylindrical region of the body bounded above by costal cartilages, ribs, and sternum (xiphoid) and below by iliac and pubic bones (green area in image below). 

 

Anatomists typically divide the abdominal wall into anterolateral and posterior parts. The term, anterolateral, means the front (antero-) and sides (-lateral) of the wall. The term, posterior, refers to the back of the wall. 

These regions are best demonstrated in a cross-section (horizontal) through the torso. 

The figure below shows the two regions. The area bound by blue lines is the posterior abdominal wall. The remainder of the large pink oval is the anterolateral abdominal wall. (Psst….Dinna fret about all the names. Will explain below). 

Anterolateral Abdominal Wall (AAW): Succinctly put, the anterolateral abdominal wall is the flexible and expandable part…. a.k.a., the belly. The posterior abdominal wall has limited flexibility and is unable to expand to any significant degree.

The main reason the AAW can expand is because it is made of soft tissue layers (no bones). The layers vary depending on the site. The following image is a cross-section of the AAW above the navel. 

The central area marked as linea alba is a vertical line of connective tissue that unites right and left halves of the AAW. It is a nearly bloodless line and therefore can be cut with little blood loss.

On either side of the linea alba are right and left rectus abdominis muscles. These run vertically. 

Using the image below, at the sides of the AAW, three layers of muscle appear, from outer to inner: 

    • external abdominal oblique (EAO)
    • internal abdominal oblique (IAO) 
    • transversus abdominis (TA). 

The following image shows the muscle pattern  from a frontal (anterior) view. Note the linea alba. Clearly, the belly wall enjoys a good deal of muscular support.

So, how thick is the AAW? Well, that depends on the individual. Moving to the next image, a magnified cross-section through the AAW, we find that the lateral AAW is composed of nine layers (three are muscle layers)! 

    • Skin
    • Fat layer (we accumulate varying amounts of fat in this layer)
    • Superficial fascia
    • EAO
    • IAO
    • TA
    • Transversalis fascia (connective tissue)
    • Extraperitoneal layer (more fat and connective tissue)
    • Peritoneum (membrane lining abdominal cavity

Nearer the midline,  AAW is composed of seven layers because it has only one muscle layer, the rectus abdominis. 

Either way, that is a LOT of layers!

Functions of the AAW: You might ask why is this part of the body designed to be flexible and expandable? Here are some reasons:

    • Maintains upright position
    • Moves the trunk (rotation, flexion, extension, bending sideways)
    • Protects abdominal viscera
    • Absorbs shock (remember BJR punching Claire in stomach in ep 106?)
    • Supports pregnancy
    • Increases intra-abdominal pressure (coughing, vomiting, childbirth, sneezing, defecation)

It is a darn good thing the AAW is flexible, especially for a pregnant woman. The next image shows a fetus during the third trimester. The uterine wall is labelled. The red arrow indicates the muscle layer of the AAW.

It as well as the other layers expand dramatically over the course of a pregnancy. The relatively slow growth of the fetus allows the belly wall to accommodate to the stretching, usually without tears, although these do occur (hernia).  This image is close to Malva’s condition when she was murdered.

So, there we have it in a nutshell, albeit a rather large one. We need an intact AAW to function well in our lives as it serves multiple purposes.

Learn more about the AAW in Anatomy Lesson #16, “The Abdomen.” There is much more to learn about this part of our anatomy – Lesson #16 explores this in greater depth. 

NOTE: The AAW is essentially the same in females and males except the groin region, there we find differences. Lesson #16 explains these.

FX: Now, how well did Starz FX do with Outlander 606? Pretty darn good if you ask me. Here are some examples:

    • As Claire begins her cut, there is a small stream of blood-tinged fluid which is consistent with the location of the cut, that is, very near the linea alba (see above). There would be little blood flow at this point as the cut is only through the belly wall. 
    • Malva’s navel does not look realistic because it appears largely normal. In late pregnancy, it usually pooches outwards due to increased intra-abdominal pressure.
    • The pink tissue underlying the skin is fat. It is a bit thick for Malva who is a trim young woman.
    • After Claire’s knife pierces the uterine wall and she removes the infant, the C-section now appears dark red because the uterus receives a huge blood supply during pregnancy. Well done. 
    • Malva’s infant is covered with blood-tinged material, the vernix, a waxy coating to protect the infant’s skin. Yay!
    • Malva’s belly is slightly concave after the infant was removed. Horrible, but accurate. 
    • Mouth-to-mouth on such a tiny person should be done with less force than Claire used – third trimester lung volume is calculated at less than 2 tablespoons per lung! This can accommodate a very tiny amount of air.
    • Claire doing two finger chest compression to stimulate the heart is spot on.

Yay, Outlander! Kudos to the FX folks!

Read about Claire’s emergency C-section in Diana’s sixth big book, “A Breath of Snow and Ashes!”

I smelled the blood and saw her in the same instant. She was lying in the salad bed, her skirt flown out like some gigantic, rusty flower blooming amid the young lettuces. 

I was kneeling by her, with no memory of reaching her, and the flesh of her arm was warm when I grasped her wrist—such small, fragile bones—but slack, there was no pulse—Of course not, said the cold small watcher inside, her throat is cut, there’s blood everywhere, but you can see the artery isn’t pumping; she’s dead. 

Malva’s gray eyes were open, blank with surprise, and her cap had fallen off. I clutched her wrist harder, as though I must be able to find the buried pulse, to find some trace of life … and did. The bulge of her belly moved, very slightly, and I dropped the flaccid arm at once and seized my knife, scrabbling for the hem of her skirt. 

I acted without thought, without fear, without doubt—there wasn’t anything but the knife and the pressure, the flesh parting and the faint possibility, the panic of absolute need…

I slit the belly from navel to pubis, pushing hard through slack muscle, nicked the womb but no matter, cut quick but careful through the wall of the womb, dropped the knife, and thrust my hands into the depths of Malva Christie, still blood-warm, and seized the child, cupping, turning, wrenching hard in my frenzy to pull it free, bring it out from sure death, bring it into the air, help it breathe.… Malva’s body flopped and heaved as I jerked, limp limbs flailing with the force of my yanking. 

It came free with the suddenness of birth, and I was swiping blood and mucus from the tiny sealed face, blowing into its lungs, gently, gently, you have to blow gently, the alveoli of the lungs are like cobwebs, so small, compressing its chest, no more than a hand’s span, two fingers pressing, no more, and felt the tiny spring of it, delicate as a watch spring, felt the movement, small squirms, a faint instinctive struggling—and felt it fade, that flicker, that tiny spark of life, cried out in anguish and clutched the tiny, doll-like body to my breast, still warm, still warm. 

“Don’t go,” I said, “don’t go, don’t go, please don’t go.” But the vibrancy faded, a small blue glow that seemed to light the palms of my hands for an instant, then dwindle like a candle flame, to the coal of a smoldering wick, to the faintest trace of brightness—then everything was dark. 

I was still sitting in the brilliant sun, crying and blood-soaked, the body of the little boy in my lap, the butchered corpse of my Malva beside me, when they found me.

Puir Claire! Puir Malva! Puir wee one!

See Claire as she realizes that all is lost. Mother and child are gone – grief, loss, and futility grip the Good Doctor.

The deeply grateful,

Outlander Anatomist

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Photo Credits: Starz; www.aafp.org; www.anatomyqa.com; www.kenhub.com; www.musculoskeletalkey.com; www.quora.com; www.stanfordchildrens.org

Footnote: In 2017, the United Nations Office on Drugs and Crime reported 87,000 killings of women worldwide – 58% were killed  by family members  or intimate partners! Alarming stats!