Lab 04 - Posterior Arm and Hand Anatomy Notes

Lab \#4 ======= Upper Extremity: Posterior Forearm & Hand ========================================= A. Bones: --------- **Review** **1. Ulna** -- medial bone of forearm a. olecranon process\* b. coronoid process c. trochlear (semilunar) notch d. radial notch e. ulnar tuberosity f. in...

Lab \#4 ======= Upper Extremity: Posterior Forearm & Hand ========================================= A. Bones: --------- **Review** **1. Ulna** -- medial bone of forearm a. olecranon process\* b. coronoid process c. trochlear (semilunar) notch d. radial notch e. ulnar tuberosity f. interosseous border g. posterior border h. styloid process\* i. head **2. Radius** -- lateral bone of forearm a. head b. neck c. radial tuberosity d. interosseous border e. dorsal tubercle f. ulnar notch g. styloid process\* ***\*Surface Anatomy* -- using surface anatomy identify as many features of the bones as possible** In the wrist region, there are eight short bones, which are collectively called the carpal bones. Each one has their own name as seen in the list below. There are two rows, composed of four bones each. The first four bones listed are in the proximal row (first to fifth digit), and the next four are in the distal rows (first to fifth digit). Overall, the carpal bones enable the range of motion of the wrist. **3) Carpal bones** a. scaphoid ("boat") b. lunate ("crescent moon") c. triquetrum (three articular surfaces) d. pisiform ("pea-shaped") e. trapezium (four sided) f. trapezoid (four-sided) g. capitate ("head" -- the largest bone) h. hamate ("hooked") **The palm is composed of the five long bones called the metacarpals. These bones make joints between the carpals and the digits. Each one of these bones has a base, a shaft and a head. Notice that the head of each metacarpal has a round articulating surface, which aids in the movement of the digits at the metacarpal-phalangeal joint.** **4) Metacarpus** The palm of the hand is composed of **5 metacarpal bones** a. base b. shaft c. head **The phalanges are the long bones that make up the five digits. Digits two through five will have three phalanges a proximal, middle and distal. The first digit, the pollex (thumb), only has a proximal phalanx and a distal phalanx. Notice that difference between the head of the phalanges and the metacarpals, the phalanges have a flat head that only permits for flexion and extension.** **5) Phalanges** d. base e. shaft f. head **\* *Surface Anatomy*** -- Identify these segments using surface anatomy B. Joints of the Hand --------------------- **The joints of the hand permit for the dexterity that we enjoy. The radiocarpal joint permits for the flexion, extension, adduction, abduction, and circumduction of the manual region. The intercarpal joints will slide with each other to help with mobility. The Carpometacarpal (CMC) joints of digits two to five permits for a limited variety of movement, however this is not true for the first digit. The first CMC is the only saddle joint within the body and permits for the movements of the thumb. The maneuverability of the digits two through five is through the metacarpal-phalangeal joint instead. Please look at each joint and note the articulating surfaces, overall structural, overall functional, synovial function, and synovial structural classifications.** **Fill in the articulating surfaces by studying the available images** +-----------------+-----------------+-----------------+-----------------+ | **JOINT NAME** | **ARTICULATING | **STRUCTURAL | **MOVEMENT(S)** | | | SURFACES** | CLASSIFICATION* | | | | | * | | +=================+=================+=================+=================+ | **Carpometacarp | | Saddle | flexion | | al** | | | | | | | | extension | | **(CMC) of | | | | | thumb** | | | abduction | | | | | | | | | | adduction | | | | | | | | | | circumduction | | | | | | | | | | opposition | +-----------------+-----------------+-----------------+-----------------+ | **Carpometacarp | | Plane | Gliding for | | al | | | digits 2 to 5 | | (CMC) of | | | | | fingers** | | | | +-----------------+-----------------+-----------------+-----------------+ | **Metacarpalpha | | Condyloid | flexion | | langeal | | | | | (MCP)** | | | extension | | | | | | | | | | abduction | | | | | | | | | | adduction | | | | | | | | | | circumduction | +-----------------+-----------------+-----------------+-----------------+ | **Interphalange | | Hinge | flexion | | al | | | | | (IP)** | | | extension | | | | | | | **(proximal + | | | | | distal)** | | | | +-----------------+-----------------+-----------------+-----------------+ **\**Surface Anatomy*** -- Identify these joints using surface anatomy C. Blood Vessels ---------------- Identify the following blood vessels on the readings available and program. ### Arteries **Radial --** **Ulnar --** **Interosseous (common, anterior, posterior) arteries --** **Superficial palmar arch --** **Deep palmar arch --** ### Veins **Median cubital vein --** **Median antebrachial vein --** D. Muscles ---------- **The posterior compartment of the antebrachial region is composed of predominately extensors and supinators. This compartment can be broken into three groups -- muscles that move the wrist, muscles that move the digits, or muscles that move the pollex. The names of the muscles will indicate actions or region insertion.** **The muscles of the hand are in three locations, the thenar region, (act on the pollex), the hypothenar (act on the fifth digit), and the palm region (the short muscles of the hand). The short muscles of the hand include the lumbricals, which have no boney origin, and the interossei. The interossei are also named for being in between the metacarpals. A handy tip to remember the actions of the interossei is PAD and DAB, where the palmar interossei will adduct the digits, and the dorsal interossei will abduct the digits.** Information in the below tables has come from chapter 3 of your text ### Posterior Forearm Muscles +-----------+-----------+-----------+-----------+-----------+-----------+ | **Muscle* | **Proxima | **Distal | **Innerva | **Blood | **Main | | * | l | Attachmen | tion** | Supply** | Action(s) | | | Attachmen | t** | | | ** | | | t** | | | | | | | | **(Insert | | | | | | **(Origin | ion)** | | | | | | )** | | | | | +===========+===========+===========+===========+===========+===========+ | Anconeus | Lateral | Olecranon | Radial | Deep | Extension | | | epicondyl | process, | nerve | brachial | at elbow | | | e | posterior | | artery, | | | | of | , | | recurrent | | | | humerus | proximal | | interosse | | | | | portion | | ous | | | | | of ulna | | artery | | +-----------+-----------+-----------+-----------+-----------+-----------+ | Extensor | Lateral | Base of | Radial | Radial | Extension | | carpi | supracond | metacarpa | nerve | Artery | , | | radialis | ylar | l | | | and | | longus | ridge of | 2 | | | abduction | | | humerus | | | | of hand | +-----------+-----------+-----------+-----------+-----------+-----------+ | Extensor | Lateral | Base of | Radial | Radial | Extension | | carpi | epicondyl | metacarpa | nerve | artery | , | | radialis | e | l | | | and | | brevis | of | 3 | | | abduction | | | humerus | | | | of hand | +-----------+-----------+-----------+-----------+-----------+-----------+ | Extensor | Lateral | Bases of | Radial | Posterior | Extension | | digitorum | epicondyl | middle | nerve | interosse | at | | | e | and | | ous | metacarpo | | | of | distal | | artery | phalangea | | | humerus | phalanges | | | l | | | | of digits | | | and | | | | 2 to 4 | | | interphal | | | | | | | angeal | | | | | | | joints, | | | | | | | extension | | | | | | | of hand | +-----------+-----------+-----------+-----------+-----------+-----------+ | Extensor | Lateral | Extensor | Radial | Posterior | Extension | | digiti | epicondyl | expansion | nerve | interosse | at | | minimi | e | of digit | | ous | metacarpo | | | of | 5 | | artery | phalangea | | | humerus | | | | l | | | | | | | and | | | | | | | interphal | | | | | | | angeal | | | | | | | joints | | | | | | | for digit | | | | | | | 5 | +-----------+-----------+-----------+-----------+-----------+-----------+ | Extensor | Lateral | Base of | Radial | Ulnar | Extension | | carpi | epicondyl | metacarpa | nerve | artery | and | | ulnaris | e | l | | | adduction | | | of | 5 | | | of hand | | | humerus | | | | | +-----------+-----------+-----------+-----------+-----------+-----------+ | **Deep | | | | | | | muscles** | | | | | | +-----------+-----------+-----------+-----------+-----------+-----------+ | Supinator | Lateral | Anterior, | Radial | Radial | Supinatio | | | epicondyl | lateral | nerve | recurrent | n | | | e, | surface | | artery | of | | | radial | of | | | forearm | | | collatera | proximal | | | | | | l, | third of | | | | | | annular | radius | | | | | | ligaments | | | | | | | , | | | | | | | supinator | | | | | | | crest of | | | | | | | ulna | | | | | +-----------+-----------+-----------+-----------+-----------+-----------+ | Extensor | Posterior | Tendon of | Radial | Posterior | Extension | | indicis | surface | the | nerve | interosse | of digit | | | of distal | extensor | | ous | 2, | | | ulna, | digitorum | | artery | adduction | | | interosse | at level | | | of digit | | | ous | of the | | | 2, | | | membrane | second | | | extension | | | | metacarpa | | | at wrist | | | | l | | | | +-----------+-----------+-----------+-----------+-----------+-----------+ | Abductor | Posterior | Base of | Radial | Posterior | Abduction | | pollicis | surface | metacarpa | nerve | interosse | and | | longus | of ulna, | l | | ous | extension | | | radius, | 1 | | artery | of digit | | | interosse | | | | 1, | | | ous | | | | abduction | | | membrane | | | | of hand | +-----------+-----------+-----------+-----------+-----------+-----------+ | Extensor | Posterior | Base of | Radial | Posterior | Extension | | pollicis | surface | distal | nerve | interosse | of digit | | longus | of ulna, | phalanx | | ous | 1 at | | | and | of digit | | artery | interphal | | | interosse | 1 | | | angeal | | | ous | | | | joint, | | | membrane | | | | | | | | | | | extension | | | | | | | of digit | | | | | | | 1, | | | | | | | abduction | | | | | | | of hand | +-----------+-----------+-----------+-----------+-----------+-----------+ | Extensor | Posterior | Base of | Radial | Posterior | Extension | | pollicis | surface | proximal | nerve | interosse | of digit | | brevis | of radius | phalanx | | ous | 1, | | | and | of digit | | artery | abduction | | | interosse | 1 | | | of hand | | | ous | | | | | | | membrane | | | | | +-----------+-----------+-----------+-----------+-----------+-----------+ \* ***Surface Anatomy*** -- Identify as many tendons as possible using surface anatomy ### Intrinsic Muscles of the Hand These muscles, which originate on the carpal and metacarpal bones, provide fine motor control of the hand. #### I. Muscles that act on the 1^st^ digit (Thumb) called Thenar muscles +-----------+-----------+-----------+-----------+-----------+-----------+ | **Muscle* | **Proxima | **Distal | **Innerva | **Blood | **Main | | * | l | Attachmen | tion** | Supply** | Action(s) | | | Attachmen | t** | | | ** | | | t** | | | | | | | | **(Insert | | | | | | **(Origin | ion)** | | | | | | )** | | | | | +===========+===========+===========+===========+===========+===========+ | Flexor | Flexor | Base of | Medan and | Radial | Flexion | | pollicis | retinacul | proximal | ulnar | artery | of first | | brevis | um, | phalanx | nerves | | digit, | | | trapezium | of digit | | | aids in | | | , | 1 | | | oppositio | | | trapezoid | | | | n | | | , | | | | of digit | | | capitate | | | | 1 | +-----------+-----------+-----------+-----------+-----------+-----------+ | Abductor | Flexor | Base of | Median | Radial | Abduction | | pollicis | retinacul | proximal | nerve | artery | of first | | brevis | um, | phalanx | | | digit, | | | scaphoid, | of digit | | | aids in | | | and | 1 | | | oppositio | | | trapezium | | | | n | | | | | | | of digit | | | | | | | 1 | +-----------+-----------+-----------+-----------+-----------+-----------+ | Adductor | Capitate, | Base of | Ulnar | Deep | Adduction | | pollicis | second | proximal | nerve | palmar | of first | | | and third | phalanx | | arch | digit, | | | metacarpa | of digit | | | assists | | | ls | 1 | | | on | | | | | | | flexion | | | | | | | of digit | | | | | | | 1 | +-----------+-----------+-----------+-----------+-----------+-----------+ | Opponens | Flexor | Lateral | Median | Radial | Oppositio | | pollicis | retinacul | side of | nerve | artery | n | | | um, | metacarpa | | | of digit | | | trapezium | l | | | 1 | | | | 1 | | | | +-----------+-----------+-----------+-----------+-----------+-----------+ \* ***Surface Anatomy*** -- Identify as many tendons and muscles as possible using surface anatomy **Keep in mind that the actions of the thumb will be at 90^o^ to the rest of the digits.** **\ ** #### II. Muscles that act on the 5^th^ digit (little finger) called hypothenar muscles +-----------+-----------+-----------+-----------+-----------+-----------+ | **Muscle* | **Proxima | **Distal | **Innerva | **Blood | **Main | | * | l | Attachmen | tion** | Supply** | Action(s) | | | Attachmen | t** | | | ** | | | t** | | | | | | | | **(Insert | | | | | | **(Origin | ion)** | | | | | | )** | | | | | +===========+===========+===========+===========+===========+===========+ | Flexor | Hook of | Base of | Ulnar | Ulnar | Flexion | | digiti | hamate, | proximal | nerve | artery | of digit | | minimi | flexor | phalanx | | | 5, | | brevis | retinacul | of digit | | | assists | | | um | 5, palmar | | | in | | | | surface | | | oppositio | | | | | | | n | | | | | | | of digit | | | | | | | 5 | +-----------+-----------+-----------+-----------+-----------+-----------+ | Abductor | Pisiform | Base of | Ulnar | Ulnar | Abduction | | digiti | and | proximal | nerve | artery | of digit | | minimi | tendon of | phalanx | | | 5, | | | flexor | of digit | | | assists | | | carpi | 5, ulnar | | | in | | | ulnaris | surface | | | oppositio | | | | | | | n | | | | | | | of digit | | | | | | | 5 | +-----------+-----------+-----------+-----------+-----------+-----------+ | Opponens | Hook of | Shaft of | Ulnar | Ulnar | Oppositio | | digiti | hamate, | metacarpa | nerve | artery | n | | minimi | flexor | l | | | of digit | | | retinacul | 5, ulnar | | | 5 | | | um | surface | | | | +-----------+-----------+-----------+-----------+-----------+-----------+ \* ***Surface Anatomy*** -- Identify as many tendons and muscles as possible using surface anatomy #### III. Muscles that act on digits \#2-4 +-----------+-----------+-----------+-----------+-----------+-----------+ | **Muscle* | **Proxima | **Distal | **Innerva | **Blood | **Main | | * | l | Attachmen | tion** | Supply** | Action(s) | | | Attachmen | t** | | | ** | | | t** | | | | | | | | **(Insert | | | | | | **(Origin | ion)** | | | | | | )** | | | | | +===========+===========+===========+===========+===========+===========+ | Palmar | Base of | Base of | Ulnar | Palmar | Adduction | | interosse | metacarpa | proximal | nerve | metacarpa | of digits | | i | ls | phalanx | | l | 1, 2, 4, | | (1, 2, 3) | 1, 2, 4, | of | | arteries | 5. | | | 5 | related | | | Assists | | | | fingers | | | in | | | | and | | | flexion | | | | extensor | | | at MCP | | | | aponeuros | | | joints, | | | | is | | | extension | | | | | | | at IP | | | | | | | joints | +-----------+-----------+-----------+-----------+-----------+-----------+ | Dorsal | Adjacent | Bases of | Ulnar | Dorsal | Abduction | | interosse | sides of | proximal | nerve | and | of digits | | i | all | phalanges | | palmar | 2 to 4, | | (1, 2, 3, | metacarpa | , | | metacarpa | flexion | | 4) | ls | extensor | | l | at MCP | | | | expansion | | arteries | joints, | | | | of digits | | | and | | | | 2 to 4 | | | extending | | | | | | | IP joints | +-----------+-----------+-----------+-----------+-----------+-----------+ | Lumbrical | Surfaces | Extensor | 1 and 2 | Superfici | Flexion | | s | of flexor | aponeuros | -- median | al | at MCP | | (1, 2, 3, | digitorum | is | nerve | palmar | joints, | | 4) | profundus | on dorsal | | arch, | extension | | | tendons | surface | 3 and 4 | common | at IP | | | | of | -- ulnar | palmar | joints | | | | phalanges | nerve | digital | for | | | | | | arteries, | digits 2 | | | | | | deep | to 5 | | | | | | palmar | | | | | | | arch, | | | | | | | dorsal | | | | | | | digital | | | | | | | artery | | +-----------+-----------+-----------+-----------+-----------+-----------+ **What you should know:** - Blood vessels of the Posterior compartment of forearm and hand - Bony features of the ulna, radius, carpals, metacarpals, phalanges - Bone siding (left or right) of ulna and radius - Joints and articular features of hand - Muscles of the posterior forearm compartment and hand (origins, insertions, innervations, actions and blood supply) Reference --------- Moore, K.L, Agur, A.M.R., Dalley, A.F. (2015) ***Essential Clinical Anatomy, 5^th^Edition**.* Baltimore, United States: Wolters Kleuwer Health Biel, A. (2019). ***Trail Guide to the Body (6th Edition)*.** Boulder, CO, USA: Books of Discovery