Gross Anatomy Learning Objectives - Limbs

7/28/2019 Gross Anatomy Learning Objectives - Limbs

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Gross Anatomy Learni ng ObjectivesUpper and Lower L imb

Lecture 1Introduction to the Anatomy of the Limbs

Dr. Mike Snow, April 30, 2012

1. Differentiate a fibrous joint from a cartilaginous joint from a synovial joint.

F ibrous joint Cartil aginous joint Synovial join t(see above)Articulating bones joined by

dense CT

No joint cavity

None to very little movement

Ex: Interosseous membrane,

sutures of skull

Found in mid-sagittal plane in

adults and at the ends of

growing long bones in kid

Articulating bones joined by

articular (hyaline) cartilage

or fibrocartilage

No joint space, Limited

movement

Ex: IV disks, growth/ epiphyseal

plate

Most common type of joint, with 5 features:

1. Have a true joint spacehigh degree of movement

2. Weight bearing surfaces covered by articular (hyaline)

cartilage -cushions articular surfaces

3. Bones held together by a capsule of dense CTloss of

SS pain and propioceptive fibers

4. Synovial membrane lines capsule and all non-weight

bearing surfaces

5. Synovial fluids fills joint spacelubricates joint

surfaces and provides nutrients for hyaline cartilage

2. Determine a muscles action(s) by its position relative to a joint axis.

See Right

3. Define the actions possible at the shoulder and hip joints.

See Right4. List the muscles, actions and innervation associated with the dorsal scapular region.

5. List the muscles, actions, and innervation associated with the gluteal region.Muscle Action I nnervation

Glenohumeral Joint Ventral Rami of C5-T1Brachial PlexusSupraspinatus M Abduction Suprascapular nerve

Deltoid M Abduction, Flexion, Medial Rot. Axillary Nerve

Infraspinatus Lateral Rotator Suprascapular nerve

Teres Minor Lateral Rotator Axillary Nerve

Pectoralis Major Medial Rotator, Flexion Medial Pectoral Nerve, Lateral Pectoral N

Subscapularis Medial Rotator

Coracobrachialis Flexion

Anterior Deltoid Flexion

Short head of the biceps FlexionTeres Major Extension, Medial Rotator Branch of the Brachial Plexus

Latissimus dorsi Extension, Medial Rotator

Long head of the triceps Extension

Posterior Deltoid Extension

Hip Joint Ventral Rami of L2-S3Lumbosacral plexusGluteus maximus Inferior Gluteal Nerve

Gluteus medius Abductor Superior Gluteal Nerve

Gluteus minimus Abductor Superior Gluteal Nerve

Tensor fasciae latae Abductor Superior Gluteal Nerve

Piriformis Lateral Rotator

Obturator internus Lateral Rotator

Obturator externus Lateral Rotator

Quadratus femoris Lateral Rotator

Iliopsoas FlexorSartorius Flexor

Rectus Femoris Flexor

Semitendinosus Extension Tibial Nerve

Semimembranosus Extension Tibial Nerve

Biceps femoris, short head Extension Common fibular Nerve

6. Define the concept of collateral circulation based on the dorsal scapularanastomosis

Multiple pathways to each muscle so that muscles are rarely ischemic


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Lecture 2Human Limb Development

Dr. Mike Snow, May 1, 2012

1. State which embryonic germ layer gives rise to skeletal muscle.

Mesoderm

2. List the adult derivatives stemming from the three subdivisions of a somite.Sclerotome: vertebrae around the neural tube and notochord

Dermomyotome: dermis and all muscles of the limb and trunk

3. Describe the embryonic processes by which nerves and muscles appear in the limb bud.

Muscle precursor cells from the myotome region of the somite migrate to three regions to form the deepback, the trunk, and the limb muscles. These cells then migrate into the limb bud to form two groupings a post

axial (posterior division, extensors) and pre-axial (anterior division, flexors).

4. Define the embryonic rationale for the extensor and flexor compartments of the adult.

Muscles on the posterior side will pull a bone to resting position, or extend it, while the opposite is true

or muscles on the anterior side. In the adult, flexors and extensors are on opposite sides. This occurs becausethe upper and lower limbs rotate in opposite directions.

5. Explain the embryonic rationale for the dermatome patterns seen inthe limbs.

At first, the limb bud is innervated in the same belt-like fashion

of the trunk. As the limb bud elongates, the middle dermatomes are carried distally to the hand.Lower limb dermatomes reflect the medial rotation that occurs during embryonic development

6. Describe the steps by which a muscle fiber develops from a precursor cell (myoblast).

MyoblastMyotube Muscle Fiber

7. Categorize the more common limb malformations.

Reduction Defects: meromelia (part of limb), Amelia (entire limb)

Duplication Defects: polydactyl (extra digit), supermumery (extra limb)Fusion of Digits: syndactyly (simple or complex)

Lecture 3Innervation Patterns of LimbsDr. Mike Snow, May 2, 2012

1. Describe the innervation patterns within the compartments of the upper and lower limbs.

2. Define the brachial plexus in terms of its roots, trunks, divisions, cords and terminal branches.

3. Describe the concept of how axons from a given spinal cord segment are found in multiple nerves.Spinal nerves can take all exits from its initial root, but cannot go backwards, and thus will not be able

to reach all parts of the brachial plexus.

4. List the nerves affected with an upper or a lower brachial plexus lesion. Describe the symptoms associated

with upper and lower brachial plexus injuries.

Musculocutaneous: C5, CAxillary is only C5, C6

Radial N.: C5-T1Medial N: C5-T1

Ulnar N: C8, T1


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Upper Brachial Plexus Injury (Erb-Duschenne Palsy): Tearing, stretching or avulsion of the C5, C6 ventral

rami or upper trunk. Occur with a strong force causing excessive stretching of neck relative to fixed shoulder.1. Suprascapular (all)loss of abduction at shoulder joint (limb adducted), loss of infraspinatus2. Axillary (all)loss of abduction at shoulder joint (limb adducted), waiters tip deformity3. Musculocutaneous (most)loss of elbow flexors (elbow slightly extended)4. Radial (some)weakness of wrist extension (slight flexion)

Lower Brachial Plexus Injury (Klumpkes Palsy): Can occur with any strong foreces causing excessive

stretching of the upper limb relative to the trunk1. Primarily affects ulnar nervereduced function of the hand, claw hand

5. Define a dermatome and indicate the locations for clinically testing the dermatomes of the

upper/lower limbs.Dermatomes are all SS axons from a single spinal nerve which innervate a specific area of

the skin of the upper limb.L4 over knee cap and big toe C6 on thumb

L5 on middle toes C7 on middle finger

S1 on little toe C8 on pinkie finger

6. Differentiate a dermatome from a peripheral cutaneous nerve.

Cutaneous nerves are SS axons that are distributed to the skin of the upper limb via cutaneous branches of

the terminal branches of the brachial plexus. Absence or reduced sensation in any of the fields shown in the

diagram indicates damage to either the terminal nerve or its cutaneous branch.Femoral n: anterior thigh A: axillary n

Obturator n: medial thigh R: radial n

Common fibular n: MC: Musculocutaneous n

Superficial: ant shin, dorsum of middle toes M: median n

Deep: dorsal webbing between big and second toes U: ulnar n

Lecture 4Gross Structure and Function of Muscle, Part 1

Dr. Gene Albrecht, May 3, 2012

1. Define and apply the terms, principles and concepts shown in bold italic typeMuscular system

Skeletal muscles

Cardiac and smooth muscleEndomysium

Muscle fibers

Motor End plate (NMJ)

Muscles fascicles (bundles)

Perimysium

Epimysium

Motor nerve: SS, SM, Symp/post

Motor unit

Shoulder Position

Glenohumeral joint

Concentric contraction (shorten)

Isometric contractionEccentric contraction (lengthen)

Parallel fibered muscles

Pennate muscles

Tendons + parallel muscles

Tendons + pinnate muscles

Prime mover

Antagonist

Fixator (stabilizer)

Synergist

Gravity

Electromyography (EMG)

Anatomical Inspection

What to know about skeletal m:

Name

Form, shape, disposition

Attachments

Innervation

Anatomical Action

Muscle Function

Relationships

2. Contrast the basic features of skeletal muscle compared to cardiac and smooth muscleSkeletal M Cardiac M Smooth M

Cell Structure Striated, v. long, cylindrical, parallel,multinucleated muscle fiber, electricallyisolated from neighboring muscle fibers

Striated, cylindrical, short,branching, mononucleated,

electrically coupled

Nonstriated, fusiform, short,mononucleated, electrically coupled

Function Move bones and other structures to whichmuscles attach, acts as venous and

lymphatic pump

Constrict heart to pump blood

through chambers

Constricts lumen size of vessels, move

contents through ducts and organs via

peristalsis, skin hairs

Type ofContraction

All-or-nothing of all muscle fibers

innervated by a single motor unit

Rapid, continuous, spreading Slow, sustained, and spreading; may

contract in waves

Control Voluntary, except reflex and unconsciousCNS influence

Involuntary with inherent

rhythm

Involuntary

Innervation Motor neuron with cell body in CNS(anterior horn of SC and brain stem)

ANS with preganglionic neuron in CNS and posts in symp or parasymp

ganglia of PNS


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3. Describe the hierarchical structure of muscle from molecules to whole muscle,

including its CT layer.See Left

4. Discuss how you would determine if a muscle is specialized for movement asopposed to power in terms of fiber length, cross-sectional area, and fiber architecture.

Force generated by a muscles is proportional to the cross-sectional area of itsmuscle fibers (not weight) and movement is proportional to the length (and

orientation) of its muscle fibers, which can shorten by about 30%.5. Discuss the meaning of the phrase muscles spared when ligaments suffice relativeto muscle tone and posture using examples from the upper limb.

Muscles are generally silent at rest. Ligaments hold the bones in their resting

position. In some cases, ligaments are not enough and some minimal contraction of a

muscle might be needed at rest, as is the case of the upper trapezius in the shoulderjoint. Resting position is maintained with mechanisms that maintain joints against the

downward pull due to the weight of the limb.

6. Define shortening (concentric), isometric, and lengthening (eccentric) contraction of

muscle and give several examples of each.

Concentric contraction occurs when a muscle becomes shorter during contraction. The muscle as a whole isdoing active work by generating more force than any external forces there may be (gravity, inertia, etc).

Isometric contraction occurs when a muscle remains the same length during contraction. The muscular

force and external forces are balanced to keep the two attachments of the muscle the same distance apart.Eccentric contraction occurs when a muscle becomes longer while contracting. The muscular force is less

than the external forces of the muscle stretched despite active contraction.

7. Discuss the role of tendons as part of the MSK system

Tendons are 100-200 times stronger than muscles. They have the architectural advantage of small size

where muscles cross joints and the physiological advantage of providing required length at low metabolic cost.Tendons in parallel muscles reduce movement but not force, and reduce force but not movement in pennate m.

8. Define prime mover (agonist), antagonist, fixator (stabilizer), and synergist relative to muscle function.

Prime mover: main muscle for a motion

Antagonist: opposes action of a prime mover

Fixator: stabilizes joint positionSynergist: eliminates and controls unwanted movements (fist flexors + extensors)

9. Discuss the importance of gravity and inertia in movement and muscle function.

Gravity and inertia are often the prime movers. Muscles often function as antagonists to resist and/or

control gravity and inertia acting on body parts

10. Differentiate anatomical action from muscle function when discussing what a muscle does.

Anatomical Action refers to motions at a joint produced by the shortening contraction of a muscle acting alone.Muscle function is the way a muscle functions in everyday life in a coordinated effort with other muscles.

Lecture 5Gross Structure and Function of Muscle, Part 2Dr. Gene Albrecht, May 3, 2012

1. Describe the anatomical actions of the deltoid muscle relative to each axis for movement that occur at the

shoulder joint.

Anterior Part: flexion around transverse axis of humeral head and medial rotation around longitudinal

axis, most anterior fibers produce adductionLateral Part: abduction, pinnate arrangement of lateral fibers

Posterior part: extension around transverse axis, lateral rotation around longitudinal axis, adduction


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2. List the anatomical actions of the biceps brachii muscle and explain its role as an antagonist to gravity during

extension at the elbow.Flexes arm at shoulder joint, flexes forearm at elbow joint, and supinate forearm. When extending the

elbow, the biceps act as an antagonist to gravity, contracting eccentrically to control extension.

3. Define protonation and supination, explain how the radius rotates relative to the

ulna and identify the muscles responsible for these movements

Supination: rotate forearm so palms face up

Protonation: rotate forearm so palms face downThe radius rotates over the ulna in pronation

Pronator quatrausn Pronator teres: pronation

Supinator, biceps brachii:supination (biceps if elbow flexed, force)

4. Discuss the role of the biceps brachii, supinator, triceps, and shoulder muscles in supinationMuscles Role Slow unresisted

supination

Fast supination

with elbow flexed

Fast supination with

elbow extended

Supination against

resistance

Supinator Prime Mover + + + +Biceps Prime Mover - + - +Triceps Synergist - + - +Shoulder muscles Stabilizers - + - +

5. Describe the structure and function of the sternoclavicular, acromioclavicular, and Scapulothoracic joints.

Sternoclavicular joint: Extremely strong, articular disc acts as a ligament that tethers the

clavicle to the sternum, considerable ball-and-socket like mobility, elevated up to 60 andmove forward/back up to 30

Acromioclavicular: strength provided by coracoclavicular ligament which causes the

scapula to be pulled along with any movement of the clavicle and vice versa;Dislocation=shoulder separation

Scapulothoracic joint: no bone-to-bone articulation but there is considerable movement

of the scapula on the body wall, the scapula is held in place by the muscles of the shoulder

girdle that pass from the body wall (pec minor, trap, serratus ant, rhomboids, and levatorscapulae)

6. Discuss the role of each muscle involved in abducting the arm above the head.

Trapezius: Upper fibers elevate clavicle (and scapula), and retract, middle

fibers retract scapula, lower fibers depress scapula and rotate glenoid fossaupwards, and retract

Serratus Anterior: Protract scapula, lower fibers rotate glenoid fossa

upwards

Deltoid and supraspinatus abduct the humerus ~90

Lecture 6Human Gait

Dr. Mike Snow, May 8, 2012

1. Define the gait cycle, including 4 of its parts (heel-strike, mid stance, toe-off, and swing).Heel str ike: the instant the heel touches the ground;

"loading response"

Foot Flat: entire plantar surface of the foot incontact with the ground

Mid-stance: body directly over stance limb

Heel-Off: heel leaves ground.Pre-swing:big toe leaves the ground; toe-off

Earl y Swing:immed. After toe leaves the ground.Late Swing:just prior to heel touching ground.


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2. Draw the vertical line of gravity relative to the sacral promontory, and hip, knee & ankle joints.

Pass posterior to hip joint, tendency to extend trunk at hipresist by tautness of iliofemoralligament in front of hip joint capsule

Pass anterior to knee, tendency to extendresist by tautness of cruciate ligaments & joint capsule

Pass anterior to ankle, tendency to dorsiflexresist by contraction of soleus

3. Describe how excessive pelvic tilt is controlled during gait and the muscles involved.

Pelvic tilt is controlled by isometric contraction of the gluteus medius and minimus.

4. Indicate the muscles, or muscle groups, that are active during parts of the gait cycle, and indicate ifeach muscle is acting by an eccentric or a concentric contraction.Phase Muscles Contr action Acti on

Heel-Strike

Gluteus Maximus & Hamstring Isometric Hip Extensors, prevent trunk from pitching forward

Gluteus Medius and Minimus Isometric Prevent pelvis from tilting to swing side

Ankle dorsiflexors Eccentric Offset gravity and set foot on ground in controlled fashion

Foot Flat

Gluteus Medius and Minimus Isometric Prevent pelvis from tilting to swing side

Quadriceps EccentricKeep knee from buckling as entire body weight transferred to

stance limb

Mid-StanceGluteus Medius and Minimus Isometric Keep pelvis from tilting to side of swing leg

Plantar flexors Eccentric Prevent unwanted dorsiflexion at ankle

Heel-OffGluteus Medius and Minimus Isometric Prevent pelvic tilt toward swinging limb

Plantar flexors (calf) Concentric Lift heel off ground and contribute to forward thrust

Pre-SwingPlantar flexors Concentric Provide forward thrustHip flexors Concentric Stop extension at hip, initiate forward movement of limb

Early Swing

Ankle dorsiflexors Concentric Lift toes, prevent from stubbing on ground

Iliopsoas and hip flexors Concentric Accelerate forward motion of limb

Quadriceps Isometric Prevent Unwanted excessive flexion at knee

Late SwingHamstring Eccentric

Slow forward momentum of thigh/leg in preparation for setting

heel on ground

Dorsiflexors Isometric Hold toes up in readiness for heel strike

5. Describe abnormal gaits associated with nerve lesions to muscles of the lower limb.Lesion Deficit Gait

Superior Gluteal n. Gluteus medius and minimus Throwing upper body to side of lesion

Iliopsoas m paralysis Iliopsoas paralyzed Impossible to walk, cannot bring limb forwardHip extensor paralysis Gluteus maximus or hamstrings Leaning backward at heel-strike to keep from

pitching forward at waist

Tibial Nerve Calf muscles (plantar flexors)inability to raise the

heel off the ground

Small steps and dragging the limb forward

Deep Fibular

(peroneal) Nerve

Ankle dorsiflexorsfoot cant decelerated after heel-

strike, toes cant clear ground in swing phase

High stepping gait

Obturator Nerve Adductors of the upper leg Limb deviating laterally during swing phase

Lecture 7Functional Anatomy of the Hand

Dr. Thomas McNeil, May 10, 2012

1. Know the basic anatomical movements of the wrist, fingers and thumb.

Radiocarpal: flexion, extension, abduction & adductionCarpometacarpal of the digits 1-5: flexion, extension, abduction, adduction & rotation

Metacarpophalangeal (MP): flexion, extension, abduction, adduction & limited rotation

Interphalangeal (IP) of digits 1-5: flexion & extension onlyThumb itself: Flexion, extension, abduction, adduction & opposition

Carpal bones:

S. Scaphoid L. Lunate

T. Triquetrum P. Pisiform

Tm. Trapezium Td. Trapezoid

C. Capitate H. Hamate (*=hook)


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2. Know the innervation and anatomical functions of the intrinsic muscles of the hand.Muscle I nnervation Anatomical Function

Thenar muscles of thumbAbductor pollicis brevisFlexor pollicis brevis

Opponens pollicis

Median n (recurrentbranch)

Abduct, flex and oppose the thumb

Hypothenal muscles of little fingerAbductor digiti minimi

Flexor digiti minimiOpponens digiti minimi

Ulnar n Abduct, flex and oppose the 5th digit

Interossei Ulnar n DorsalAbduction, Extend IP, Flex MP

PalmarAdduction, Extend IP, Flex MP

Lumbricals 1st, 2ndmedian n

3rd, 4thulnar n

Extend IP joint, Flex MP joint

Adductor pollicis Ulnar n Brings thumb into the palm of the hand

3. Know the cutaneous innervation of the hand and fingers.

4. Know what clinical tests are used to test for median, ulnar and radial nerve injuries.Nerve Lesion Deficit Cli nical Test

Ulnar N-at elbow, fracture of medial

epicondyle or dislocation ofelbow-Klumpkes palsy

Claw hand due to effect on both intrinsic andextrinsic muscles in chronic state

Pt cannot AD or ABduct their fingersLoss of sensory innervation to little finger and

hypothenar eminence

Patient unable to grip or squeeze apiece of paper if placed between

their fingers

Median N

-at wrist in attempted suicide

Ape hand in chronic state

Pt cannot oppose thumb and fingerLoss of sensory innervation to thenar eminence

Pt cant grip an object to pick it up

Radial N-fracture of humerus shaft

Pt cannot extend wristLoss of sensory innervation to dorsal surface of hand

Pt can still extend digits due tolumbricals

Lecture 8The Knee JointDr. Michelle Winfield, May 14, 2012

1. Describe the bones and articular surfaces that form the knee joint, and relate them to the motion at the joint

Hinge:flexion/extension,around transverse axis (140)

Rolling and Gliding: onarticular surfaces

Rotation: around verticalaxis (30-40)


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2. Discuss the morphology and function of the menisci (cartilages)

Morphology: thin, crescent-shaped fibrocartilage positioned on top of the tibial condyles to create slightlymore concave tibial surfaces for receiving the convex femoral condyles. Medial meniscus is C-shaped, Lateral

is circular. Attached by a variety of ligaments to the tibia, both as margins and to intercondylar region.

Function: stabilization, shock absorption, lubrication, and spacing

3. Understand the position, function and importance of the collateral and cruciate ligaments

Lateral/Medial collateral ligaments: vertical, thickened band;

thickening of the joint capsule, MCL attaches to the medialmeniscus, LCL does not attach to the lateral meniscus

Function: Aid in transverse stability of the knee, prevent

hyperextension

Anterior/Posterior cruciate ligaments: strong rounded cords

that cross each other as they span between the intercondylareminence of the tibia and the intercondylar surface of the femur

Function: tense during full flexion and extension, act to control

rotation, ant-post stability

4. Describe the fibrous capsule, synovial membrane and the bursae of the knee

Fibrous capsule closes the knee joint and is reinforced by multiple tendons and ligaments. The synovialmembrane lining the synovial membrane of the knee joint is the moist extensive and complicated in the body. It

connects every point of articulation within the knee.

5. Consider a clinical case of knee injury to illustrate functional anatomy

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Gross Anatomy Learning Objectives - Limbs