Exam 4: Hand Worksheet Flashcards
Identify/explain the following:
Distal and proximal palmar creases
See the picture
- If there is just one crease (instead of distal and proximal) it is a sign of Down’s Syndrome.
- Usually gives us an estimation of axis of MCP (outward signs of where motions are).
- If I make a splint that is short of these creases, it allows motion.
- If I make a splint past these lines, it limits motion.
- If I make a terrible splint at these lines, it creates skin breakdown and pain.
What attaches skin to bone in the hand?
Cleland and Grayson ligaments
Identify/explain the following:
Thenar crease
where skin is moving for opposition movement (see picture)
- Same significance of hand creases
- If we want to allow opposition, we need to allow room for the size of the thenar eminence and the crease.
- If we want to prevent opposition, we need to go way past the crease.
Identify/explain the following:
Surgical no-man’s land
Portion of the hand where surgery is generally a disaster!
Dr. Bringmand said “Below proximal crease, above distal crease.” (I believe) But this dosen’t make sense.
I think we previously learned it was the distal palmar crease to the crease that goes with the PIP joint (middle finger crease?). Still confused on this one.
Zone II in the picture
Identify/explain the following:
Proximal and distal thumb creases
Finger creases (distal, middle, proximal)
Basicically important for the same reasons as the other creases:
- Must stop short or go well past (just like the other creases). DO NOT STOP RIGHT AT THE CREASE!
(we didn’t discuss thumb creases in class specifically, but this is what he said about finger creases)
Identify/explain the following:
- Wrist Creases
Same principles of the importance of going beyond crease to prevent movement, stopping well short of crease to allow motion, do not stop on crease or it will hurt and cause break down
- Special consideration for wrist is that there is a lot more force involved at the wrist. Make sure splint goes high enough on the forearm to prevent movement
Where do finger flexors form a single sheath?
From Wikipedia:
The common synovial sheath for the flexor tendons or the ulnar bursa[1] is a synovial sheath in the carpal tunnel of the human hand.
It contains tendons of the flexor digitorum superficialis and the flexor digitorum profundus, but not the flexor pollicis longus.[2]
The sheath which surrounds the flexores digitorum extends downward about halfway along the metacarpal bones, where it ends in blind diverticula around the tendons to the index, middle, and ring fingers. It is prolonged on the tendons to the little finger
Identify/explain the following:
- Thenar eminence
- Hypothenar eminence
Find the proximal, distal, and longitudinal arches of the hand (pg 396).
What supports them?
Why are they important?
- Three Arches
- Proximal transverse arch,
- Fixed arch
- made from distal row of carpal bones and taut volar carpal ligament
- Part of the carpal tunnel
- Provides mechanical advantage to the flexors, maximizing grasp function
- distal transverse arch;
- mobile arch
- because of mobile ulnar fourth and fifth CMC joints and highly mobilie thumb CMC.
- located at the level of the metacarpal heads
- allows for optimal grasping abilities
- mobile arch
- longitudinal arch
- spans the length from the metacarpal to the distal phalanx
- disruption of this arch occurs in pts who have sustained an ulnar nerve injury with resulting loss of intrinsic muscle function
- Proximal transverse arch,
- All the arches Allow spherical grasp and normal functioning of the hand
What is okay to use when rehabing spherical grasp?
what is not okay?
- Use a squishy ball (NOT A TENNIS BALL, because it splays the hand)
- Use putty
- The individual digit hand squeezer thing is great (gripmaster) (pictured)
Explain the stiffness/mobility of metacarpals
Remember Stiffness of metacarpals (metacarpals for first finger and second finger stiffest; metacarpals for ring and baby finger very mobile. If this mobility is lost, hand will be stiff and you will not be able to use spherical grasp, so we must rehab it).
Contrast skin on the palmar (volar) side of the hand to skin on the dorsal side of the hand.
Palmar skin is very thick (working side of our hand)
- Protection
- Grip
- Doesn’t move much. Fixed.
- More susceptible to contracture after injury, causes excessive flexion
Dorsal skin
- Thin
- Loose
- Allows motion
- Injury to dorsal skin, can cause contractures too limiting flexion
What are Cleland and Grason Ligaments?
They attach skin to bone
Name the proximal carpal bones (and palpate them)
- scaphoid (navicular)
- lunate,
- triquetrium
- pisiform
Name the distal carpal bones (and palpate them)
- trapezium
- trapezoid
- capitate
- hamate
What is the pneumonic that will help with remembering the carpal bones?
(and how do you use it?)
- Some (scaphoid)
- Lovers (Lunate)
- Try (Triquitrum)
- Positions (Pisiform)
- That (Trapezium)
- They (Trapezoid)
- Can’t (Capitate)
- Handle (Hamate)
Look at palmar side of hand. Start next to the thumb on the proximal row of carpals and and go across towards pinky finger as you name them.
After P, go back next to thumb, this time start at the distal row and go across again towards pinky finger as you name them.
What is the closest metacarpal to the capitate?
The third metacarpal
What bones form the CMC of the thumb?
Is there another common name for that joint?
Trapezium and first Metatarsal
trapeziometacarpal joint (TMC)
(It is unique because it is a saddle joint)
What defines the anatomic snuffbox? (upper and lower borders and floor)
Ulnar (medial) border: Tendon of the extensor pollicis longus.
Radial (lateral) border: Tendons of the abductor pollicis longus and extensor pollicis brevis. (the APL is the most radial, the EPB is longer and
Proximal border: Styloid process of the radius.
Floor: Carpal bones; scaphoid and trapezium.
Roof: Skin
What other structures can be found in the anatomical snuff box (besides the upper and lower borders and floor)?
- Cephalic Vein
- Radial Artery
- Superficial Radial Nerve
Where is the ulnar syloid?
Styloid process of ulna
where is the radial syloid?
styloid process of radius
Where is lister’s tubercle?
What does it do?
at wrist, Lister’s tubercle is palpable on dorsum of radius;
- it serves as a pulley for the EPL;
Where is the tunnel of Guyon?
What is its significance (what does it contain)?
- depression between pisiform & hook of hamate is converted into fibrosseous tunnel, the tunnel of Guyon, by pisohamate ligament;
- the ulnar nerve bifurcates within the canal into superficial and deep branches
- deep branch of the ulnar nerve (more radial) and superficial branch more ulnar
- depression between pisiform & hook of hamate is converted into fibrosseous tunnel, the tunnel of Guyon, by pisohamate ligament;
- tunnel of Guyon is clinically significant because it contains ulnar nerve and artery & is site for compression injury;
- ulnar artery is immediately adjacent and radial to the ulnar nerve;
- tunnel of Guyon is clinically significant because it contains ulnar nerve and artery & is site for compression injury;
More detail from Orthobulltes.com:
Guyon’s Canal, formed by
- roof - superficial palmar carpal ligament
- floor - deep flexor retinaculum, hypothenar muscles
- ulnar border - pisiform and pisohamate ligament
- radial border - hook of hamate
How do you find/palpate the hook of the hamate?
Put DIP of one thumb on the pisiform of the other hand, then lay the thumb down on palm in the direction of the index finger. The hook of the hamate should be palpable close to the tip of the thumb in this position.
Carpal tunnel: Location and significance (what is in it?)
Bordered by flexor retinaculum and carpal bones (trapezium, Trapezoid, Capitate, and Hamate)
Contains the median nerve and 9 flexor tendons (the tendons of the Flexor digitorum profundus [4 deepest], Flexor digitorum superficialis [two sets of two more superficial], and FPL tendon)
Can get carpal tunnel syndrome from pinching the median nerve in the carpal tunnel.
**Ulnar nerve, ulnar artery, and palmaris longus tendon run outside of carpal tunnel on palmar side.
**radial artery runs outside of carpal tunnel on dorsum of hand
**The flexor retinaculum is attached radially to the scaphoid tubercle and the ridge of trapezium, and on the ulna side to the pisiform and hook of hamate
What is the difference in function of the 2nd and 3rd metacarpals as opposed to the 4th and 5th?
2nd and 3rth mtacarpals are more stable
4th and 5th metacarpals are more flexible
This allows spherical grasp and stability in the hand
What is the most commonly fractured carpal bone?
Scaphoid
What tendon inserts on the base of the 3rd metacarpal?
I have come up with two answers:
- Tendon of Adductor Pollicis (Oblique Head)
- Tendon of Extensor Carpi Radialis Brevis
It makes more sense to me that we should remember the Adductor Pollicis Oblque head, since the thumb is a major consideration for creating hand splints.
I emailed Dr. Bringman. Here is what he said:
“You are correct [about thinking the Adductor Pollicis Oblique Head was more important for us to remember]. Extensor carpi radialis brevis is also a prime extensor of the wrist and should be given due credit as well. As this muscle extends it also passive creates finger flexion and is of the utmost importance for individuals that would be using a tenodesis grip.”
I would remember both
How do you perform Finkelstein’s test?
what is it for?
used to diagnose De Quervain’s tenosynovitis
Perform Tinel’s Sign
What does it test?
Tinel’s sign is a way to detect irritated nerves. It is performed by lightly tapping (percussing) over the nerve to elicit a sensation of tingling or “pins and needles” in the distribution of the nerve
For example, in carpal tunnel syndrome where the median nerve is compressed at the wrist, Tinel’s sign is often “positive” causing tingling in the thumb, index, middle finger and the radial half of the fourth digit. (most associated with carpal tunnel syndrome, but can be used to test other nerves)
Perform Phalen’s test
What does it test?
Phalen’s test is a provocative test used in the diagnosis of carpal tunnel syndrome
Press dorsum of hands together (reverse prayer position) and maximally flex wrists for at least 1 minute. Positive is reproduction of symptoms (pain, tingling, etc in the median nerve distribution)
Define Dupuytren’s contracture
a condition in which there is fixed forward curvature of one or more fingers, caused by the development of a fibrous connection between the finger tendons and the skin of the palm.
Define Trigger finger
Trigger finger, also known as stenosing tenosynovitis (stuh-NO-sing ten-o-sin-o-VIE-tis), is a condition in which one of your fingers gets stuck in a bent position. Your finger may straighten with a snap — like a trigger being pulled and released.
Trigger finger occurs when inflammation narrows the space within the sheath that surrounds the tendon in the affected finger. If trigger finger is severe, your finger may become locked in a bent position.
More:
Stenosing tenosynovitis is a condition commonly known as “trigger finger.” It is sometimes also called “trigger thumb.” The tendons that bend the fingers glide easily with the help of pulleys. These pulleys hold the tendons close to the bone. This is similar to how a line is held on a fishing rod (Figure 1). Trigger finger occurs when the pulley becomes too thick, so the tendon cannot glide easily through it (Figure 2).
Purpose of the lumbricals
The lumbricals are intrinsic muscles of the hand that flex the metacarpophalangeal joints and extend the interphalangeal joints.[1]
Swan neck deformity
(PIP joint is hyperextended, DIP is hyperflexed); caused by slippage of the flexors to dorsal side the joint line in PIP
Boutonniere deformity:
PIP is hyperflexed, DIP is hyperextended; caused by slippage of extensors to palmar side of PIP)
Mallet finger
Extensor detaches from distal phalange: forceful flexion of a fully extended finger.
Jersey Finger:
rupture flexor tendon Flexor profundus: Grabs jersey, strong extension and it pops off. Only distal phalange cannot flex. Surgery has a very very poor success rate. Better outcomes if surgery is done early.
Colles fracture
FOOSH onto wrist hyperextension extension with pronated forearm, Distal radius fractures and displaces dorsally. Typically occurs to elderly population
Smith fracture:
Reverse of Colles fracture. FOOSH. Direct blow to dorsum of hand (wrist hyperflexes, and is supinated. Typically from a backwards fall. Typically occur in elderly individuals. Volar displacement.
Bennett’s fracture:
Base of the first metacarpal bone (CMC). Thumb is extended and axial force on thumb causes fracture at CMC joint. Pop someone in helmet, or shoulder pad. Horrible place to have a fracture. Thumb will be going to be out of sync for a while.
Boxer’s fracture:
More common than Bennett’s fracture. Drunk friend punches wall (and hits stud). Breaks head of the metacarpal (most commonly fourth or fifth)
Gamekeeper’s thumb:
pops thumb UCL. Repetative stress. Or skiing. Also called Skier’s thumb. Causes instability and decreased ability to hold on to things.
Sensory Distribution of the Radial Nerve
Basic;
Sensory: Innervates most of the skin of the posterior side of forearm, and the dorsal surface of the lateral side of the palm, and lateral three and a half digits.
Nerve roots: C5-T1.
Detailed:
Sensory Functions
There are four branches of the radial nerve that provide cutaneous innervation to the skin of the upper limb:
- Lower lateral cutaneous nerve of arm – Innervates the lateral aspect of the upper arm, below the deltoid muscle.
- Posterior cutaneous nerve of arm – Innervates the posterior surface of the upper arm.
- Posterior cutaneous nerve of forearm – Innervates a strip of skin down the middle of the posterior forearm.
- Superficial branch of the radial nerve – Innervates the dorsal surface of the lateral three and half digits, and their associated palm area.
Motor distribution of midian nerve
Basic:
Motor functions: Innervates the flexor muscles in the anterior compartment of the forearm (except the flexor carpi ulnaris and part of the flexor digitorum profundus, innervated by the ulnar nerve). Also supplies innervation to the thenar muscles and lateral two lumbricals in the hand.
Detailed:
The median nerve innervates the majority of the muscles in the anterior forearm, and some intrinsic hand muscles.
The Anterior Forearm
In the forearm, the median nerve directly innervates muscles in the superficial and intermediate layers:
- Superficial layer: Pronator teres, flexor carpi radialis and palmaris longus.
- Intermediate layer: Flexor digitorm superficialis.
The median nerve also gives rise to the anterior interosseous nerve, which supplies the deep flexors:
- Deep layer: Flexor pollicis longus, pronator quadratus, and the lateral half of the flexor digitorum profundus (the medial half of the muscle is innervated by the ulnar nerve).
In general these muscles perform pronation of the forearm, flexion of the wrist and flexion of the digits of the hand.
Sensory distribution of median nerve
Basic:
Sensory functions: Gives rise to the palmar cutaneous branch, which innervates the lateral part of the palm, and the digital cutaneous branch, which innervates the lateral three and a half fingers on the anterior (palmar) surface of the hand.
Nerve roots: C5 – T1.
Detailed:
The median nerve is responsible for the cutaneous innervation of part of the hand. This is achieved via two branches:
- Palmar cutaneous branch – Arises in the forearm and travels into the hand. It innervates the lateral aspect of the palm. This nerve does not pass through the carpal tunnel, and is spared in carpal tunnel syndrome.
- Palmar digital cutaneous branch – Arises in the hand. Innervates the palmar surface and fingertips of the lateral three and half digits.
Motor Distribution of the Ulnar Nerve
Basic:
Motor functions: Innervates the muscles of the hand (apart from the thenar muscles and two lateral lumbricals), flexor carpi ulnaris and medial half of flexor digitorum profundus.
Detailed:
The ulnar nerve innervates muscles in the anterior compartment of the forearm, and in the hand.
The Anterior Forearm
In the anterior forearm, the muscular branch of the ulnar nerve supplies two muscles:
- Flexor carpi ulnaris – Flexes and adducts the hand at the wrist.
- Flexor digitorum profundus (medial half ) – Flexes the fingers.
The remaining muscles in the anterior forearm are innervated by the median nerve.
The Hand
The majority of the intrinsic hand muscles are innervated by the deep branch of the ulnar nerve.
The hypothenar muscles (a group of muscles associated with the little finger) are innervated by the ulnar nerve. It also innervates some other muscles of the hand:
- Medial two lumbricals
- Adductor pollicis
- Interossei of the hand
The other muscles in the hand (such as the thenar eminence) are innervated by the median nerve.
Sensory Distribution of Ulnar nerve
Basic:
Sensory functions: Innervates the anterior and posterior surfaces of the medial one and half fingers, and the associated palm area.
Spinal roots: C8-T1.
Detailed:
There are three branches of the ulnar nerve that are responsible for its cutaneous innervation.
Two of these branches arise in the forearm, and travel into the hand:
- Palmar cutaneous branch: Innervates the skin of the medial half of the palm.
- Dorsal cutaneous branch: Innervates the skin of the medial one and a half fingers, and the associated palm area.
The last branch arises in the hand itself:
- Superficial branch – Innervates the palmar surface of the medial one and a half fingers.
Draw the sensory areas of the radial, ulnar, and median nerves on your hand.
