Intro to the Hand ppt 1
How many IP joints does the thumb have?
1
How many thumb flexor extrinisc muscles are there?
1
How many DOF does the IP joint have? What motions does it perform?
1 DOF- flexion and extension
The 1st MCP joint of the thumb has how many DOF? What motions are performed?
1 DOF- performs flexion/ extension
How are the IP joints broken up/ into section?
1 IP in thumb 4 PIP joint in digits 2-5 4 DIP joints in digits 2-5
How many phalangeal bones are in a hand?
14 total
The hand is made up of ___ bones, ___ joints, multiple ligaments, and _____ different muscle groups
19, 19, and 7
What is the stable link in the thumb chain>
1st MCP joint because of the high mobility of the 1st CMC joint
How many finger flexor extrinsic muscles are there?
2
Extrinsic thumb tendons have ____ extensors, ___ abductor, and ____ flexor
2, 1, 1
How many IP joints do digits 2-5 have?
2- Proximal and Distal (PIP&DIP)
How many bones are found in the wrist and hand?
29 bones
How many extrinsic thumb muscles do we have?
3
How many finger extensor extrinsic muscles are there?
3
How many thumb extensor/abductor extrinsic muscles are there?
3
How many DOF does the thumb CMC joint have? To perform what motions?
3 DOFs to perform flexion, extension, abduction, adduction, opposition, reoposition
How many middle phalanges are in a hand?
4
How many CMC joints in the hand are there?
5
How many MCP joints in the hand are there?
5
How many distal phalanges are there in a hand?
5
How many metacarpal bones are in a hand?
5
How many proximal phalanges are in a hand?
5
How many collateral ligaments does each finger have?
6
Within the long finger flexors, there are 2 muscle bellies that control ____ long tendons that cause flexion of ____ and ____ joints of digits 2-5
8, DIP and PIP joints
How many IP joints in the hand are there?
9
How many muscles act on the thumb?
9
What extrinsic muscle abducts and extends the 1st CMC joint and assists with wrist extension or radial or deviation?
APL
What extrinsic muscle extends the CMC joint of the thumb?
APL and EPB and EPL
Volar plates help stabilize joints against ______________ and increase the range of motion for ________
Against hyperextension; Increase range of flexion
What type of joint is the CMC? with what type of capsule?
Basal/ Saddle joint; it has a thick, loose packed capsule
Where is the IP joint found?
Between the thumb's distal and proximal phalanx.
What does CMC stand for?
Carpometacarpal joint
At the MCP joints, are metacarpals convex or concave? What does this mean?
Convex- thus the metacarpals turn within the concave phalanges at the MCP joint
The FDP has 4 different tendons of the ____ in each digit
DIP
What is another name for the posterior extrinsic muscles? What are they all?
Digit Extensors; (6): EDC, EI, EDM, EPL, EPB, and APL
What is another name for anterior extrinisc muscles? What are they all?
Digit Flexors; (3) FDS, FDP, and FPL
Where is the distal end of the bone of the distal phalanx found?
Directly under the fingernail
What does DIP stand for?
Distal Interphalangeal Joint
Put the Phalanges/Joints in order from distal (found under finger nail) to the wrist (proximal) PIP joint, CMC joint, MCP joint, DIP joint, IP joint, Carpals, Distal phalanx, middle phalanx, metacarpal, proximal phalanx
Distal Phalanx DIP Joint Middle Phalanx (not on thumb) PIP Joint Proximal Phalanx IP Joint- (just at thumb) MCP Joint Metacarpal CMC Joint Carpals
What extrinsic muscles assist with wrist extension?
EDC, EDP, APL, EPB, and EPL
What are the names of EDC, EI, EDM, EPL, EPB, and APL? What do they stand for?
EDC= Extensor digitorium communis EI= Extensor indicis EDM= Extensor digitorium minimi EPL= Extensor pollicis longus EPB= Extensor pollicis brevis APL= Abductor pollicis longus
What extrinsic muscle extends the MCP, PIP, and DIP of the 5th digit only?
EDM
What extrinsic muscle extends the 2nd digit MCP, PIP, and DIP?
EIP
What muscle extends the CMC AND MCP joints of the thumb and assists with wrist extension?
EPB
What muscle extends the thumb CMC MCP and IP?
EPL
_____, _____, and ___ are in the extensor compartments of long thumb tendons and have synovial sheaths
EPL, EPB, and APL
What makes up the anatomical snuff box?
EPL, EPB, and APL tendons- form a triangle on the radial side of the hand
We can only full abduct/ adduct the MCP joints when fingers are __________
Extended
What extrinsic muscle extends the MCP, PIP, DIP of digits 2, 3, 4, and 5?
Extensor digitorium communis (EDC)
What extrinsic muscles is a 4 joint muscle that performs DIP joint flexion of digits 2, ,3,4, and 5?
FDP
What muscle assists with PIP, MCP, and wrist flexion?
FDP
What extrinsic muscle(s) has 4 different tendons of the PIP in each of the digits 2,3,4, and 5?
FDS
What extrinsic muscle(s) performs PIP flexion of digits 2-5?
FDS
What extrinsic muscle(s) assist with wrist flexion?
FDS, FDP, and FPL
What extrinsic muscle(s) perform MCP flexion?
FDS, FDP, and FPL
What extrinsic muscle (s) performs thumb IP, MCP, and CMC flexion?
FPL
What are the names of FDS, FDP, FPL? (What do they stand for?
Flexor digitorium superficialis, Flexor digitoirum profundus, Flexor pollicis longus
What type of joint is the IP joint?
Hinge
What do ligaments do?
Hold joints together that have to be loose- they can get damaged
Where is the 1st CMC joint?
In the thumb
Each tendon to individual digits can work _______ of the other tendons from the same muscle
Independently
What does IP stand for?
Interphalangeal joint
What is found surround each joint of the MCP, PIP, and DIPs?
Joint capsules
What does palmar aponeurosis/fascia cover and protect?
Long finger flexor tendons
The medial and lateral collateral ligaments are both taut when __________
MCP or IP are in flexion
What are the ligaments of the digits?
Medial collateral ligament Lateral collateral ligament Transvere metacarpal ligament
What makes a 'Ray'?
Metacarpal+ phalangeals of each digit (So there is a ray for each digit)
Where do the intrinsic muscles originate from?
Metacarpals
What does MCP stand for?
Metacarpophalangeal joint
What does extrininsic mean?
Outside
The FDS has 4 different tendons of the ___ in each digit (one per digit)
PIP
What is the thick, connective tissue that spans from the flexor retinaculum up through the palm?
Palmar aponeurosis
What is another name for palmar aponeurosis?
Palmar fascia
What does PIP stand for?
Proximal Interphalangeal joint
What nerve has a sensory branch in the middle of the snuff box?
Radial nerve
What bones are found at the floor of the snuff box?
Scaphoid and trapezium
In the palm, flexor tendons are covered by a tendon sheath that holds synovial fluid to promote _______
Smooth gliding action
What digit does not have a middle phalange?
Thumb
What digit is #1?
Thumb (I)
What is the most functional and highly used joint of the hand?
Thumb CMC joint
True or False: All IP joints have volar plate systems
True
True/ False- All MCP joints have a volar plate
True
Are IP joints stable or mobile?
Very stable- but small and easily damaged
What are fibrocartilaginous discs that are found on the anterior surface of MCPs, PIPs, and DIPs that stabilize structures of the hand?
Volar plates
When are the medial and lateral ligaments loose?
When digits are in extension
Thumb muscle origins are ______ to finger and wrist muscles
distal
Volar plates slide proximally under ___________ during flexion
metacarpals
FPL is included in the ______ synovial sheath system
palmar
The extensor _______ divides the thumb and finger extensor tendons into 6 different compartments that have ___-____ tendons with independent sheaths
retinaculum; 1-4
The long finger flexors work _______ for composite finger flexors- they can work independently but have significantly less power when they do so
synergistically
