Metacarpal, phalanges, scapula, clavicle, pec muscles

Question 1

What are the articulations of the metacarpals?

Answer 1

Articulate proximally with the carpal bones and distally with the proximal phalanges

Question 2

What are the names of the metacarpals

Answer 2

Metacarpal I-thumb Metacarpal II-index Metacarpal III-middle Metacarpal IV-ring Metacarpal V-little

Question 3

What is the shape of the medial and lateral surfaces of the metacarpals

Answer 3

Concave to allow attachment of the interoessei muscles

Question 4

What are the 2 common fractures associated with metacarpals?

Answer 4

Boxer’s fracture-involves fracturing the neck of the fifth metacarpal. Usually occurs when clenched fist strikes a hard object. Causes the distal part of the fracture to be displaced posteriorly leading to a shortening of the affected finger. Bennett’s fracture- fracture of base of first metacarpal, extending into the carpal metacarpal joint. Caused by hyperabduction of the thumb.

Question 5

Parts of the phalanges on the different fingers?

Answer 5

Thumb-proximal and distal phalanx Other fingers- proximal, middle and distal phalanges

Question 6

Articulations of the scapula?

Answer 6

Articulates with the humerus at the glenohumeral joint and the clavicle at the acromioclavicular joint. In doing so, it attaches the upper limb to the trunk.

Question 7

What type of bond is the scapula?

Answer 7

Flat bone

Question 8

What are the names of the different surfaces of the scapula?

Answer 8

Costal-which means anterior Posterior Lateral

Question 9

Label this costal surface of scapula

Answer 9

Question 10

What attaches to posterior surface of scapula

Answer 10

majority of rotator cuff muscles

Question 11

What are the features of the posterior surface of the scapula?

Answer 11

Has a spine that runs transversely across the scapula that divides the scapula into 2. infraspinatous fossa lies below spine and is convex. Infraspinatous muscle originates from here

supraspinatous fossa lies above spine. Convex and smaller than infraspinatous fossa. Supraspinatouscmuscke originates from here

acromion extends from spine and arches over glenohumeral joint and articulates with clavicle

Question 12

What are the features of the lateral surface of the scapula?

Answer 12

Glenoid fossa-articulates with the humerus to form the glenohumeral joint Supraglenoid tubercle-roughening above the glenoid cavity where the long head of the biceps brachii attach

Infraglenoid tubercle-roughening inferior to the glenoid cavity where the long head of the triceps brachii attach

Question 13

Causes of scapula fractures?

Answer 13

High speed road collisions, crushing injuries, sports injuries

Question 14

What causes winging of scapula?

Answer 14

Serratus anterior muscle originates from ribs 2-8 and attaches to costal face of the scapula. It is innervated by the long thoracic nerve. If the nerve becomes damaged, the scapula will protrude from the back when pushing with the arm.This may be caused by repetitive shoulder movements, or inflammation of structures and pressing on the nerves or trauma to the shoulder. Serratus anterior muscle may become paralysed.

Question 15

Where does the clavicle extend from?

Answer 15

Sternum to the acromion of the scapula

Question 16

What are the functions of the clavicle

Answer 16

Attaches the upper limb to the trunk Protects the underlying neurovasculapr structures supplying the upper limb Transmits force from the upper limb to the axial skeleton

Question 17

What are the bony landmarks of the clavicle

Answer 17

Question 18

What is the most commonly fractured bone in the body?

Answer 18

Clavicle

Question 19

How can you fracture clavicle?

Answer 19

Falling on shoulder or outstretched hand

Question 20

What is the common point of fracture on a clavicle

Answer 20

junction at medial 2/3 and lateral 1/3 of the clavicle

Question 21

What happens during a clavicle fracture?

Answer 21

The lateral end is pulled inferiorly by weight of arm and medically by pec major. The medial end is pulled superiorly by the sternocleidomastoid muscle

Question 22

What is the nerve damage associated with clavicle fracture?

Answer 22

Suprascapular nerves (medial, intermedial and lateral nerves) may be damaged by the upwards movement of the medial part of the fracture. These innervate the lateral rotators of the upper limb at the shoulder. So if the nerves are damaged, it will cause unopposed medial rotation of the upper limb (waiter’s tip position)

Question 23

What are the names of the heads of the pec major?

Answer 23

Clavicular head-attaches to the clavicle Sternocostal head-attaches to the sternum and rib. Fibres from both heads insert to the intertubercular groove of the humerus

Question 24

Action of pec major?

Answer 24

the two heads can work together or independently. Together they adduct and medically rotate the humerus at the shoulder. The clavicular head also performs flexion

Question 25

What is the pec major innervated by

Answer 25

pec major innervated by the medial and lateral pectoral nerves, which are derived from the brachial plexus. Clavicular head-c5,c6 Sternocostal head-c7,c8,t1

Question 26

Location of pec minor?

Answer 26

Lies posterior to pec major and originates from ribs 3-5

Question 27

Action and innervation of pec minor?

Answer 27

Contraction of pec minor depresses the shoulder and innervated by medial and lateral pectoral nerve

Question 28

Action and innervation of serratus anterior

Answer 28

Rotates scapula to raise arms above 90 degrees. Also holds the scapula against the rib cage-this is particluarly useful when upper limb reaches anteriorly (e.g.punching) C5,c6,c7

Question 29

What can happen if a breast tumour gets too big?

Answer 29

It can invade pec muscles