Hand pt 1

Articulating Surfaces for the 2nd-5th CMC joint

Articulating Surfaces for the 2nd-5th CMC joint

Distal row of carpal bones → Bases of the metacarpal bones

Type of Joint and Movements in the 2nd-4th CMC jt

Flexion-Extension (1DoF)

True/False: The 2nd and 3rd CMC joints are immobile

True

Most flexible joint in the hand

5th CMC; Saddle joint

Movements available in the 5th CMC joint

Flexion-extension

Abduction-Adduction

(2 DOF), with limited opposition

Least Mobile; Central Pillar of the hand

3rd CMC

Loose packed Position of the 2nd-5th CMC joints

Neutral

Articulating Surfaces of the 1st CMC joint

Between the trapezium to Base of Thumb

Which surface of the 1st CMC joint is convex during flexion-extension

Transverse Diameter/Surface of Trapezium

Arthrokinematics of 1st CMC joint during Abduction-Adduction

convex surface of the thumb metacarpal is moving on the fixed concave diameter of trapezium → Opposite Roll and Slide

Arthrokinematics of 1st CMC joint during Flexion-Extension

concave articular surface of the metacarpal moving across the convex diameter of trapezium → Same Roll and Slide

Plane and Axis of 1st CMC Abduction-Adduction

Sagittal Plane - X axis

Plane and Axis of 1st CMC Flexion-Extension

Frontal Plane - z axis

OPP of 1st CMC

Neutral

CPP of First CMC

Full opposition

Articulating Surfaces of MCP jonits

Heads of the metacarpal ones → Bases of the Proximal Phalanges

OPP of MCP joints

Slight flexion, ulnar deviation

CPP of MCP joints

Full flexion, except 1st is full extension

Arthrokinematics of MCP joints during Flexion-Extension

Same direction roll and slide

Arthrokinematics of MCP joints during Abduction-Adduction

Same direction roll and slide

What type of joints are the MCP joints

Synovial condyloid joints = 2DoF

What type of joints are the IP joints

Synovial uniaxial hinged joints

Articulating surfaces of PIP

Heads of proximal phalanges and bases of middle phalanges

Articulating surfaces of DIP

Heads of middle phalanges and bases of distal phalanges

Articulating Surfaces of Thumb IP joint

Head of proximal phalanx and base of distal phalanx

Arthrokinematics of the IP joints

Concave bases → Convex Heads = Same direction roll and slide

Extrinsic Flexors of the Digits

1. FDS

2. FDP

3. FPL

Extrinsic Flexors of the Finfers

1. Extensor Digitorum

2. Extensor Indicis

3. Extensor Digiti Minimi

Extrinsic muscles of the thumb

1. Extensor Pollicis Longus

2. Extensor Pollicis Brevis

3. Abductor Pollicis Longus

Intrinsic Thenar Muscles

1. Abductor Pollicis Brevis

2. Flexor Pollicis Brevis

3. Opponens Pollicis

4. Adductor Pollicis

Intrinsic hypothenar muscles

1. Abductor Digiti Minimi

2. Flexor Digiti Minimi

3. Opponens Digiti Minimi

4. Palmaris Brevis

Innervation of the Flexors of the Digits

Median Nerve

Except for FDP to the ring and little finger → ulnar nerve

Innervation of the extensors

radial nerve

Innervation of the Thenar Muscles

Median nerve

Except Adductor Pollicis → Ulnar nerve

Flexor of MCP joint

Lumbricals

These balance stability and mobility in the hand

Three arches of the hand

Which arch of the hand is rigid

Proximal transverse arch

This arch is formed by the distal row of carpal bones

Proximal Transverse Arch

Keystone of the Proximal Transverse Arch

Capitate

The Distal Transverse arch is AKA _________

Metacarpal arch

The distal transverse arch is formed by what part of the metacarpals?

Metacarpal heads

Keystone of the Distal Transverse Arch

2nd and 3rd MCP joint

This arch follows the shape of the 2nd and 4rd rays

Longitudinal arch

Keystone of the longitudinal arch

2nd and 3rd MCP joint

Contents of the Dorsal Compartment

This pulley lies at the head of the metacarpal

A1

This pulley lies at the volar midshaft of the proximal phalanx

A2

This pulley lies at the distal part of the proximal phalanx

A3

This pulley lies centrally on the middle phalanx

A4

This pulley lies at the distal phalanx

A5

Cruciate pulley located between A2 and A3

C1

Pulley between A3 and A4

C2

Pulley between A4 and A5

C3