Bones of the Upper Limb

Humerus

Only bone of the arm (brachium)

Proximal epiphysis has a ball-shaped Head that articulates with the glenoid cavity to form the shoulder joint

Anatomical Neck surrounds the head

Greater and Lesser Tubercles are separated by the Intertubercular Sulcus (Bicipital Groove)

Surgical Neck is between the proximal epiphysis and the diaphysis

Diaphysis includes the Deltoid Tuberosity on the lateral side and the Radial Groove on the posterior side

Distal epiphysis has the Medial and Lateral Epicondyles, a lateral Capitulum, a medial Trochlea, and 3 fossae

A lateral Radial Fossa, a medial Coronoid Fossa, and a posterior Olecranon Fossa

Forearm (Antebrachium)

Consists of a lateral Radius and a medial Ulna held together by an Interosseous Membrane

Articulate with the humerus at the proximal ends

Articulate with the carpals at the distal ends

Articulate with each other at radioulnar Joints

Radius

Proximal epiphysis is the Radial Head that articulates with the capitulum as part of the elbow joint and with the ulna to form the proximal radioulnar joint

Radial Neck ends in the Radial Tuberosity

Distal epiphysis indents to the Ulnar Notch, the site of the distal radioulnar joint

Radial Styloid Process forms the lateral boundary of the wrist

Ulna

Proximal epiphysis includes the Trochlear Notch which articulates with the trochlea, the knoblike Olecranon, the Coronoid Process, which articulates with the coronoid fossa, and the Radial Notch, which articulates with the radial head

Distal epiphysis has the Ulnar Head and the Styloid Process

• The proximal radius and ulna fit with the distal humerus to form the elbow joint

Carpals (Wrist)

Consists of eight short bones arranged in two rows

has proximal bones and distal bones

mnemonic for carpal bones:

Some Lunchers Try Peppers That They Can’t Handle

Scaphoid, Lunate, Triquetrum, Pisiform, Trapezium, Trapezoid, Capitate, Hamate

Try reminds you about the triquetrum

The trapeziUM is by the thUMb

Proximal Carpal Bones (lateral to medial)

Scaphoid—Articulates with radius

Lunate—Articulates with radius and contacts ulna

Triquetrum—Articulates with ulna

Pisiform—Articulates with triquetrum (anteriorly)

Distal Bones (lateral to medial)

Trapezium—Articulates with scaphoid proximally

Trapezoid—Articulates with scaphoid proximally

Capitate—Articulates with scaphoid and lunate proximally

Hamate—Articulates with triquetrum proximall

Wrist Fractures

Usually occurs from direct trauma or an attempt to stop a fail with an outstretched arm

• Commonly involve the distal radius and ulna and possibly the carpals, particularly the scaphoid

• Fracture to the right is a Colles fracture of the distal radius

• Common in children and adults ages 60–69

• Incidence declines with advanced age while incidence of other fractures, such as hip fractures, increases; May result when people fail to catch themselves

• Present with pain and swelling over the injured area

• Common misconception is that an individual with a fractured bone will be unable to move the affected part (however, this is only the case if the bone is dislocated)

• Some wrist fractures are treated with simple casting while others require surgical intervention

Bones of the Hands and Fingers

manus, metacarpals, phalanges

Manus (hand)

Includes the metacarpals that articulate with the distal carpal bones proximally and the bones of the fingers (phalanges) distally

Metacarpals

numbered I-V from lateral to medial

Proximal epiphysis is the Base, the diaphysis is the Body, the distal epiphysis is the Head (form the “knuckles”)

Fingers (phalanges)

includes 14 phalanges

Fingers each have a Proximal, Middle (Intermediate), and Distal Phalanx, with Bases, Bodies, and Heads

Thumb (Pollex) only has Proximal and Distal Phalanges