Anatomy - Upper Limb (Hand)
During Depuyten Contracture which fingers are affected?
4th or 5th finger at metacarpophalangeal and proxmal IP joints
What are the short muscles of the hand and what compartment is it located?
Lumbricals located in central compartment with long flexor tendons
A patient has a distal interphalangeal joint suddenly being forced into extreme flexion (hyperflexion). What is the diagnose?
Mallet or baseball finger
What 3 septums are the palm divided in?
Medial, lateral and central septums
Fx of metacarpals occurring at one bone at a time tends to be very stable. Why?
Metacarpal bones except the 1st one are closely bond to each other. No active treatment required.
Why is the midpalmar or the thenar space important?
Nothing is in the space however bacteria can grow leading to infection
If the infection is untreated, what can happen?
spread proximally through the carpal tunnel into the forearm, anterior to the pronator quadratus and its fascia
What are some characterstics of palmar aponeurosis?
strong, well defined part part of the deep fascia of the palm, covers the soft tissues and overlies the long flexor tendons
A patient has inflammation of the tendon and synovial sheath occurs, the digit swells and movement becomes painful. What is the diagnose?
tenosynovitis
What is the main symptom of mallet or baseball finger disease?
the person cannot extend the distal interphalangeal joint.
Whats located laterally to the lateral fibrous septum?
thenar compartment containing thenar muscles
What is Depuytren Contracture?
disease of the palmar fascia resulting in progressive shortening, thickening and fibrosis of palmar fascia and aponeurosis
How does fracture of scaphoid occur?
falling directly on abducted hand
How is the direction of the pus determined?
fascial spaces in the hand
Excessive friction of tendons (abductor pollicis longus and extensor pollicis brevis) results in what?
fibrous thickening of sheath and stenosis of osseofibrous tunnel
How does Depuyten Contracture first manifest?
first manifests as painless nodular thickenings of the palmar aponeurosis that adhere to the skin
How can you restore the finger back after fx of phalanges have occurred?
have to open the area and fix it with nail or steel plate because flexor tendons are all attached there
What happens during boxers fracture?
head of the bone rotates over the distal end of shaft producing a flexion deformity
Which compartment is located medially to the medial fibrous septum?
hypothenar compartment containing hypothenar muscles
Where does the interossei lie?
in separate interosseous compartments between the metacarpals
After fracture of scaphoid, where does the pain usually occur?
lateral side of the wrist especially during dorsiflexion and abduction of hand
How do you get decreased grip strength from following a fx of hamate?
ulnar nerve is close to the hook of hamate and the nerve can be injured because of fx
A patient complains that when they flex and extend his fingers, a snap voice is heard. What is the diagnose?
- digital tenovaginitis stenosans (trigger finger or snapping finger)
How can you distinguish Hamate from the rest of the carpal bones?
- distinctive hooked process, the hook of hamte, that extends anterioly
How can you distinguish the 3rd metacarpal bone?
- distinguished by a styloid process on lateral side of its base
There are 5 metacarpal bones, what are each consist of?
- base, shaft and head
What are fibrous digital sheaths?
- cover entire finger - encloses all synovial sheaths with deep and superficial tendons of hand muscles - protective function
How is trapezium articulated?
- 1st and 2nd metacarpals, scaphoid and trapezoid bones
What is a boxers fracture?
- Fracture of 5th metacarpal - occurs when an unskilled person punches someone with a closed fist
Depuyten Contracture, describe its characteristic?
- Gradually, progressive contracture of the longitudinal bands produces raised ridges in the palmar skin - extend from the proximal part of the hand to the base of the 4th and 5th fingers.
What is the origin, insertion, innerv and action of Dorsal Interossei 1st - 4th?
- Proximal attachment Adjacent sides of two metacarpals - Distal attachment Bases of proximal phalanges; extensor expansions of 2nd - 4th fingers - Innervation Deep branch of ulnar nerve (C8, T1) - Main action Abduct 2nd - 4th fingers from axial line; act with lumbricals in flexing metacarpophalangeal joints and extending interphalangeal joints
Thenar compartment What is the origin, insertion, innerv and action of opponens pollicis?
- Proximal attachment Flexor retinaculum and tubercles of scaphoid and trapezium - Distal attachment Lateral side of 1st metacarpal - Innervation Recurrent branch of median nerve (C8, T1) - Main action To oppose thumb, it draws 1st metacarpal medially to center of palm and rotates it medially
Thenar Compartment What is the origin, insertion, innerv and action of Abductor pollicis brevis?
- Proximal attachment Flexor retinaculum and tubercles of scaphoid and trapezium - Distal attachment Lateral side of base of proximal phalanx of thumb - Innervation Recurrent branch of median nerve (C8, T1) - Main action Abducts thumb; helps oppose it
Thenar compartment What is the origin, insertion, innerv and action of flexor pollicis longus?
- Proximal attachment Flexor retinaculum and tubercles of scaphoid and trapezium - Distal attachment Lateral side of base of proximal phalanx of thumb - Innervation Recurrent branch of median nerve (C8, T1) - Main action Flexes thumb
Hypothenar Compartment What is the origin, insertion, innerv and action of opponens digiti minimi?
- Proximal attachment Hook of hamate and flexor retinaculum - Distal attachment Medial border of 5th metacarpal - Innervation Deep branch of ulnar nerve (C8, T1) - Main action Draws 5th metacarpal anterior and rotates it, bringing 5th finger into opposition with thumb
Hypothenar Compartment What is the origin, insertion, innerv and action of flexor digiti minimi brevis?
- Proximal attachment Hook of hamate and flexor retinaculum - Distal attachment Medial border of 5th metacarpal - Innervation Deep branch of ulnar nerve (C8, T1) - Main action Flexes proximal phalanx of 5th finger
Adductor Compartment What is the origin, insertion, innerv and action of adductor pollicis?
- Proximal attachment Oblique head: Bases of 2nd and 3rd metacarpals, capitate, adjacent carpals Transverse head: Anterior surface of shaft of 3rd metacarpal - Distal attachment Medial side of base of proximal phalanx of thumb - Innervation Deep branch of ulnar nerve (C8, T1) - Main action Adducts thumb toward lateral border of palm
What is the origin, insertion, innerv and action of palmar interossei 1st - 3rd?
- Proximal attachment Palmar surfaces of 2nd, 4th, and 5th metacarpals - Distal attachment Bases of proximal phalanges; extensor expansions of 2nd, 4th, and 5th fingers - Innervation Deep branch of ulnar nerve (C8, T1) - Main action Adduct 2nd, 4th, and 5th fingers toward axial line; assist lumbricals in flexing metacar-pophalangeal joints and extending interphalangeal joints; extensor expansions of 2nd - 4th fingers
Hypothenar Compartment What is the origin, insertion, innerv and action of abductor digiti minimi?
- Proximal attachment Pisiform - Distal attachment Medial side of base of proximal phalanx of 5th finger - Innervation Deep branch of ulnar nerve (C8, T1) - Main action Abducts 5th finger; assists in flexion of its proximal phalanx
What are the two things can be palpated in the snuffbox?
- Radial styloid process can be palpated proximally - base of the 1st metacarpal can be palpated distally
What is the largest carpal bone in the proximal row and how does it articulate?
- Scaphoid (know for exam and step 1) - articulates proximally with radius - has a prominent scaphoid tubercle
What are the 4 bones in the proximal row of carpals from lateral to medial?
- Scaphoid, Lunate, Triquetrium and Pisiform
From lateral to medial, the four carpal bones of distal row are?
- Trapezium, Trapezoid, Capitate, Hamate
How is triquetrum articulated?
- articulates proximally with articular disc of distal radio ulnar joint
What is the floor of the snuffbox consist of?
- formed by the scaphoid and trapezium bones - crossed by the radial artery as it passes diagonally from the anterior surface of the radius to the dorsal surface of the hand.
Distally palmar aponeurosis forms what and attaches to what?
- forms 4 longtitudinal digital bands - attaches distally to bases of proximal phalanges
Where does lateral fibrous septum extend?
- from lateral border of palmar aponeurosis to 3rd metacarpal
What septum separates the two spaces (midpalmar and thenar spaces) and where is it attached?
- lateral fibrous septum - attached to 3rd metacarpal
Palmar aspect of the hand features a central concavity which separates two eminences. What are they?
- lateral, larger and more prominent thenar eminence at base of the thumb - medial. smaller hypthenar eminence proximal to base of 5th finger
Where is pisiform bone located?
- lies on the palmar surface of the triquetrum
Is Depuyten Contracture painless and what is its treatment?
- painless nodule thickening of palmar aponeurosis - no treatment, must cut fascia to release some fibrous band and to relief patient
How is capitate articulated?
- primarily with 3rd metacarpal distally and with trapezoid, scaphoid, lunate, hamate
How does metacarpal bone articulate?
- proximal bases articulate with carpal bones - distal heads articulate with proximal phalanges and form knuckles
Lunate is located between scaphoid and triquetral bones. How is it articulated?
- proximally with radius
How does fracture of hamate occur?
- result in non-union of the fractured bony parts due to the traction by the attached muscles (particularly flexor carpi ulnaris)
Infection through the little finger can lead all the way to the forearm. Hows that possible?
- synovial sheath of the little finger is usually continuous with the common flexor sheath - may spread to the common sheath and thus through the palm and carpal tunnel to the anterior forearm, draining into the space between the pronator quadratus and the overlying flexor tendons (Parona space).
What are the tendons that comprimise anatomical snuffbox?
- tendons of the abductor pollicis longus and extensor pollicis brevis bound the anatomical snuff box anteriorly - tendon of the extensor pollicis longus bounds it posteriorly.
infection from the thumb can also reach the forearm. Hows the possible?
- via the continuous synovial sheath of the flexor pollicis longus (radial bursa).
Trapezoid resembles Trapezium, How does it articulate?
- with 2nd metacarpal, trapezium, capitate and scaphoid bones
How is hamate bone articulated?
- with 4th and 5th metacarpal, capitate and triquetral bones
Central Compartment What is the origin, insertion, innerv and action of Lumbricals?
1st and 2nd - Proximal attachment Lateral two tendons of flexor digitorum profundus 3rd and 4th - Proximal attachment Medial three tendons of flexor digitorum profundus - Distal attachment Lateral sides of extensor expansions of 2nd - 5th fingers - Innervation 1st and 2nd: Median nerve (C8, T1) 3rd and 4th: Deep branch of ulnar nerve (C8, T1) - Main action Flex metacarpophalangeal joints; extend interphalangeal joints of 2nd - 5th fingers
The wrist is composed of how many carpal bones?
8
When looking up on an xray, how can you detect fx of scaphoid?
A little gap will show up next to the bone
What muscle includes in the adductor compartment?
Adductor pollicis
What therapy has made infections spread beyond these 3 compartments rare?
Antibiotic
How do you get degnerative wrist joint disease?
Avascular necrosis of the proximal fragment of the scaphoid (pathological death of bone resulting from inadequate blood supply)
Sometimes it takes 10-14 days to reveal fx of scaphoid. Why?
Bone resorption
What is the largest carpal bone?
Capitate (know for exam)
What is the cause of Depuyten Contracture?
Its cause is unknown, but evidence points to a hereditary predisposition
Each digit has 3 phalanges inluding thumb. True or False?
False, thumb only has 2 phalanges
Where does the nail bed sit on?
Distal phalanges
Infection is minimal to none during tenosynovitis. True or false?
False infection is at great risk
Depuyten Contracture affects the medial half of the hand and not the lateral. True or False?
False, affects only the medial half and not the lateral half
Fx of phalanges are painless. True or False?
False, extremely painful because of highly developed sensation of fingers
The proximal phalanges are the smallest, the middle ones are intermediate in size, and the distal ones are the longest. True or False?
False, prox phalanges are largest and distal are smallest
Depuyten Contracture is only unilateral. True or False?
False. The contracture is frequently bilateral and is seen in some men more than 50 years of age
Give a common example of fracture of phalanges?
Finger caught in a car door
How does a painful hematoma develop?
From fx of phalanges that usually forms small parts
Depending on the pus, which three compartment will it end up in?
Hypthenar, thenar or adductor compartments
What will cause the patient to unable to extend their finger completely?
If the tendons of the flexor digitorum superficialis and flexor digitorum profundus enlarge proximal to the tunnel
what injuries lead to tenosynovitis?
Injuries such as a puncture of a finger by a rusty nail can cause infection of the digital synovial sheaths
The union of scaphoid may sometimes take up to 3 months to heal. Why?
Poor blood supply in proximal part of the scaphoid
A patient complains he has pain in the wrist that radiates proximally to the forearm and distally toward the thumb. What is the diagnose?
Quervain tenovaginitis stenosans
Fx of metacarpals heal very quickly. Why?
Rich blood supply
What is the most freq fractured carpal bone?
Scaphoid
How does one get multiple metacarpal fracture?
Severe crushing of hand resulting in instability of hand
Between the flexor tendons and the fascia covering the deep palmar muscles are two potential spaces. What are they?
Thenar and midpalmar space
1st metacarpal bone is the thickest and shortest of the other bones. True or False?
True
Each phalanx has a base proximally, a shaft and a head distally. True or False?
True
Hand infection of tenosynovitis can lead to other parts of the hand if not treated. True or False?
True
If patient not treated, necrosis will happen and its very painful. True or False?
True
If too must pus, then fibrous band can rupture and spread to other spaces. True or False?
True
Initial radiographs of fx or scaphoid may not reveal a fracture right away. True or False?
True
The palmar fascia is thin over the thenar and hypothenar eminences, but it is thick centrally where it forms the fibrous palmar aponeurosis and in the fingers where it forms the digital sheaths. True or False?
True
The phalanges of the first digits are stouter than those in other fingers. True or False?
True
The proximal end or apex of the triangular palmar aponeurosis is continuous with the flexor retinaculum and the palmaris longus tendon. True or False?
True
The proximal surfaces of the distal row of carpals articulate with the proximal row of carpals, and their distal surfaces articulate with the metacarpals. True or False?
True
The tendons of the abductor pollicis longus and extensor pollicis brevis are in the same tendinous sheath on the dorsum of the wrist. True or False?
True
What leads to mallet or baseball finger disease?
a baseball is miscaught or a finger is jammed into the base pad
What muscles include in the hypthenar compartment?
abductor digiti minimi, flexor digiti minimi brevis, and opponens digiti minimi.
What muscles include in the thenar compartment?
abductor pollicis brevis, flexor pollicis brevis, and opponens pollicis.
The deepest muscular place of the palm contains what compartment? What does it contain in it?
adductor compartment including adductor pollicis
Between the hypthenar and thenar compartments, there is a central compartment. What does it contain?
all flexor tendon sheaths, digital vessels and nerves, palmar arches including lumbrical muscles
The fascia is continuous with which two fasciaes?
antebrachial fascia and fascia of the dorsum of the hand
The swellings from hand infection usually occur where?
appear on the dorsum of the hand (not on palmar because its very thick), where the fasciae is thinner
Although most fascial compartments end at the joints, the midpalmar space is continuous with the anterior compartment of the forearm via what?
carpal tunnel
Fracture of the proximal and middle phalanges usually result from what?
crushing or hyperextension injuries
Where do medial fibrous septum extend?
deeply from the medial border of the palmar aponeurosis to 5th metacarpal