5. Flexor Forearm and Hand

Question 1

describe the boundaries of carpal tunnel
what are the contents: which muscles in which bursas

what enters superficial to the retinaculum?

Answer 1

roof : flexor retinaculum
3 bony walls formed by carpals: trapezium, trapezoid, and hamate

contents:
tendons of superficial and deep digital flexors in ulnar bursa
-tendon of flexor pollicis longus in radial bursa
-medial nerve

superficial to the retinaculum is the ulnar nerve and vessel. they enter through the canal of guy on which is a separate fibrous compartment

Question 2

describe the superficial palmar arch

where does it lay in relation to the flexors?

Answer 2

formed the by ulnar artery in the hand. it is superficial to the flexor tendons and goes through guyon’s tunnel.

-arch branches to the common palmar digital for the palm and then the proper digital for digits 2, 3,4, and 5 but only the medial part of (away from thumb) 2

joins the radial’s deep palmar arch at the dorsal palmar arch

Question 3

describe the dorsal carpal arch

Answer 3

formed by a branch of the radial artery in the anatomic snuffbox. it is combination of superficial and deep palmar arches

Question 4

where does the deep palmar arch enter the palm?

Answer 4

through the 1st dorsal interosseous

Question 5

describe the venous drainage of the hand

Answer 5

• paired radial and ulna veins from brachial veins in cubital fossa
• dorsal veins of hand drain into cephalic and basilic
• then median cubital over the cubital fossa joins cephalic and basilic
• cephalic drains lateral aspect of the forearm and joins axillary vein
• basilic drains medial aspect of forearm and joins brachial in arm (think b-b)

Question 6

describe the hypothenar eminencies, their blood supply and innervation

Answer 6

the hypothenar eminence is the muscles on the pinky side of the palm

abductor, flexor, and opponens minimi

abductor: lower so origin at the scaphoid and inserts at the proximal fx: adduction of MIP pinky
flexor: origin at hamate and inserts at the proximal. fx: flexion of PIP
opponens: same origin as flexor so origin at hamate and inserts throughout the pinky. opposes the pinky

innervation is the ulnar nerve since its the ulnar side.
*blood from SUPERFICIAL PALMAR ARCH

Question 7

describe the thenar eminencies, their blood supply and innervation

Answer 7

thenar eminencies are on the thumb side.

they are also abductor, flexor, and oppenens

abductor: origin at the bottom so the scaphoid and inserts to lateral side of 1st phalanx of thumb. fx: abduction of thumb
flexor: above the abductor so trapezium bone origin and inserts at base of proximal. does MIP (no pip for thumb) and has SUPERFICIAL AND DEEP PART
opponens: deep and does opposition of thumb.

nerve: is going to be MEDIAN RECURRENT BRANCH
BLOOD: ???

Question 8

where are the ulnar bursa
where do they begin
where do they end

Answer 8

around each digital flexor

begin proximal to flexor retinaculum and end in midpalmar compartment

except sheath to 5th digit continues to digit

Question 9

where are the radial bursa?

Answer 9

sheath for flexor pollicus longus extends into first digit

Question 10

what are the interossei and how are they numbered?

Answer 10

interossei help flex MCP while extending PIP, DIP

dorsal: 4 of them remember DAP so dorsal abduct
have btwn 2, 3, 4, remember that the midlien is the middle finger

then you have 3 on the palmar side:
on the side that moves towards the middle finger
PAD- adduct towards the middle finger (on the ventral side)

Question 11

what are the lumbricals and how many are there

what are their innervations?

Answer 11

there are 4 lumbricals that serve fingers 2 through 5

they originate from the radial side of the flexor digitorum profundus (FDP) and insert on the radial side of these fingers

-flex MCP while extending PIP and MIP like when making an L

actually relax FDP tendon when flexed

remember Median recurrent branch is LOAF so it does lumbricals I and II while the ulnar nerve does 3 and 4

Question 12

what does the median nerve recurrent branch innervate

Answer 12

Lumbricals I and II
O- opponens pollicis
A- abductor pollicis brevis
F- flexor policcis brevis

Question 13

what does the deep branch of the ulnar innervate?

Answer 13

deep part of the FOB - flexor pollicis brevis
all interossei
lumbricals 3 and 4
adductor pollicis
palmaris brevis 
hypothenar muscles

Question 14

what are the 8 bones of the wrist and what are the rows?

which bones articulate with distal radius

Answer 14

Some lovers try positions that they cannot handle:

Scaphoid, Lunate, Triquetrum, Pisiform
Trapzeium, trapezoid, capitate, hamate

scaphoid and lunate articulate with distal radius

Question 15

which bones form the radio carpal joint? what type of joint is this?

what are the movements

Answer 15

syonvial joint btwn radius and
scaphoid, lunate

mvmts: sagitall flexion/ extension and frontal adduction/abduction and cicumduction with both planes combined

Question 16

what type of joint is the MCP and which digits and what movements

Answer 16

synovial joint
digits 2, 3, 4, 5,
mvmts are flexion/extension and abduction/adduction

Question 17

what type of joints are the PIP and DIP and what are the movements?

Answer 17

synovial and flexion/extension

Question 18

what kind of joint is the 1st carpometacarpal joint? what movements

what bones?

Answer 18

saddle joint
btwn trapezium and first metacarpal

flexion/extnsion
abduction/adduction and opposition (ok sign)
and circumduction

Question 19

what are the joints btwn carpals?

Answer 19

midcarpal (different rows) and intercarpal joints (same row) plane joints
and intermetacarpal joint

Question 20

list and describe the origin insertion and action of the flexor compartment superficial muscles

Answer 20

all from medial epicondyle and innervated by median and ulnar n (ulnot median )

-all flex the elbow

pronator teres: pronation. inserts at coronoid process

• flexor carpi radialis: inserts at the 2nd metacarpal like the extensor does and flexes the wrist, abducts wrist, and flexes the elbow
• palmaris longus: inserts in palmar aponeurosis and the flexor retinaculum . fx is to felx forearm and wrist and hand joint
• flexor carpi ulnaris flexes hand and adducts wrist an flexes forearm. inserts at pisiform/hook of hamate /5th metacarpal
• flexor digitorum superficialis: inserts in shafts of medial 4 digits and does flexion of PIP, MIP

Question 21

list and describe the origin insertion and action of the flexor compartment superficial muscles

Answer 21

• flexor digitorum profundus (gets some ulna innervation) proximal attachment is the bases of distal phalanges. fx is to flex the MIP, PIP, DIP and wrist
• flexor pollicus long: fx is to flex the thumb IP and MCP joint. also ABDUCTS the radius

pronator quadratus function is to pronate

Question 22

how do you make the OK sign

Answer 22

flexor pollicus longus and flexor digitorum profundus

-need to flex PIP

Question 23

what are the proximal distal and middle radioulnar joints

what are the movements?

type of joints?

Answer 23

proximal: head of radius and ulna in radial notch of ulna. held by annular ligament
pivot joint

middle: interosseous membrane is fibrous joint and transmits force
distal: head of ulna and radius in ulnar notch of radius.

movements: rotation of radius around its longitudinal axis,
supination- palm faces anteriorly
pronation- palm faces down