Unit 1 clinical abnormalities-findings

Question 1

Injury to the back region involving lig. only, no dislocation or fx.

Answer 1

back sprain
Results from excessively strong contractions related to movements of the vertebral column such as excessive extension or rotation.

Question 2

Injury to the back involving some degree of tearing or stretching or microscopic tearing of muscle fibers

Answer 2

Back sprain
common injury in those who participate in sports
results from overly strong muscular contraction. Muscle usually involved are those producing lumbar movements of the IV joints, especially he erector spinae If the weight is not properly balanced on the vertebral column, strain is exerted on the m.
using the back as a lever when lifting puts an enormous strain on the vertebral column and lig and m.
Can be minimized by crouching, holding the back as straight as possible, and use of the buttock and lower limbs to assist with lifting.

Question 3

Protective mechanism in the back m. after an injury or in response to inflammation-attended by cramps, pain, interference with function, producing involuntary movement and distortion.

Answer 3

Back spasm

sudden involuntary contraction of one or more muscle groups.

Question 4

A pt experiences lightheadedness, dizziness and other sx when turning the head for prolonged periods, such as when backing up a motor vehicle. What is a possible explanation for their sx

Answer 4

Arteriosclerosis-hardening of the arteries.
the winding course of the vertebral arteries through he foramina transversarii of the transverse processes of the cervical vertebrae and through the sub occipital triangles becomes clinically significant when blood flow through these arteries is reduced, as occurs with arteriosclerosis. When the head is turned for prolonged periods, may cause lightheadedness, dizziness and other sx from the interference with the blood supply to the brainstem.

Question 5

A pt presents with the anterior axillary fold, formed by the skin and fascia overlying the inferior border of the pectoralis major absent on one side. The nipple on this side is also noted to be more inferior than normal. What is a possible explanation?

Answer 5

Absence of the pectoralis major muscle, sternocostal portion.
uncommon, but when it does happen, no disability usually results.
anterior axillary fold and the inferior fascia overlying the inferior border of the pec major are absent on the effected side and the nipple is more inferior than normal.
In Poland syndrome,both the pec major and pec minor are missing; breast hypoplasia and absence of 2-4 rib segments are also present.

Question 6

A pt presents with the medial border of the scapula oriented more laterally and posteriorly away from the thoracic wall than what would be considered normal. This is pronounced when the person leans on their hand or presses the upper limb against a wall when the arm is raised, the medial border and inferior angle of the scapula pull away markedly from the posterior thoracic wall.

Answer 6

Winged scapula 2/2 paralysis of the long thoracic nerve, which innervates the serratus anterior m.
The medial border of the scapula moves away laterally and posteriorly away from the thoracic wall giving the appearance of a wing, pronounced when the person leans on their had or presses the upper limb against a wall.

Question 7

Paralysis of the long thoracic nerve- In addition to the deformity known as winged scapula, which other function up the upper limb may be impacted?

Answer 7

Serratus anterior involved in abduction of the GH joint beyond 90 degrees. The pt would not be able to abduct the upper limb beyond the horizontal

Question 8

You perform a Biceps myotatic reflex on a pt (thumb over the tendon of the biceps, tap hammer over nail, should feel involuntary contraction of the biceps felt as a momentarily tensed tendon with a brief jerk like flexion of the elbow). Instead you get an excessive, diminished or hung (prolonged) response. What could this clinical finding indicate?

Answer 8

Excessive, diminished or prolonged (hung) responses may indicate central or peripheral nervous system disease or metabolic disorders such as thyroid disease. A normal response would confirm the integrity of the musculocutaneous nerve and the C5 and C6 spinal cord segments.

Question 9

Explain the mechanism for biceps tendinitis, who does it most commonly effect?

Answer 9

The tendon of the biceps is enclosed in a synovial sheath and moves back and forth in the intertubercular sulcus (bicitial groove). Wear and tear of this mechanism can cause shoulder pain. Inflammation of the tendon called biceps tendinitis is the result of repetitive microtrauma, such as that which occurs with repetitive movements like throwing a baseball, cricket or using a racquet. A tight, narrow and/or rough intertubercular sulcus may irritate and inflame the tendon producing tenderness and crepitus (crackling sound).

Question 10

Describe the mechanism for dislocation of the tendon of the long head of the biceps brachii.
when does it occur in young persons?
When does it occur in older persons?

Answer 10

Tendon of the long head of the biceps can be partially or completely dislocated from the intertubercular sulcus in the humerus Painful condition may occur in young persons during traumatic separation of the proximal epiphyses of the humerus and the injury occurs in older persons with a hx of biceps tendinitis.
A sensation of popping or catching is felt during arm rotation.

Question 11

Explain the mechanism for Rupture of the tendon of the long head of the biceps brachii
Who is most commonly effected?

Answer 11

usually results from wear and tear of an inflamed tendon as it moves back and forth in the intertubercular sulcus of the humerus.
The tendon is torn from its attachment to the supraglenoid tubercle of the scapula. The reupture is commonly dramatic and is associated with a snap or pop. Te detached muscle belly forms a ball near the center of the distal part of the the anterior aspect of the arm (Popeye deformity).
Rupture of the biceps tendon can result from forceful flexion of the arm against excessive resistance as occurs in weight lifters. However, the tendon ruptures more often as the result of prolonged tendinitis that weakens it. The rupture results from repetitive overhead motions, such as occurs in swimmers and baseball pitchers that tear the weakened tendon in the inter tubercular sulcus.

Occurs in individuals >35 yrs of age.

Question 12

Where is the best place to compress the brachial artery to control hemorrhage (apply hemostasis) and why? What is the anatomical basis? When would occlusion of the brachial artery constitute a surgical emergency?

Answer 12

Medial to the humerus near the middle of the arm because the arterial anastomoses around the elbow will provide a functionally and surgically important collateral circulation. Therefore, the brachial artery can be clamped distal to the origin of the deep artery of the arm without producing tissue damage.
The anatomical basis for this procedure is that the ulnar and radial arteries will still receive sufficient blood through the anastomeses around the elbow.
Although the collateral pathways provide some protection against gradual or temporary and partial occlusion, sudden complete occlusion or laceration of the brachial artery creates a surgical emergency because paralysis of the muscles results from ischemia of the elbow and forearm within a few hours.
Muscles and nerves can tolerate up to 6 hours of ischemia, but after this fibrous scar tissues replaces necrotic tissues and causes the involved musces to shorten permanently, producing a flexion deformity which is called an ischemic compartment syndrome (Volkmann or ischemic contracture). Flexion of the fingers and sometimes the wrist results in loss of hand power as a result of the irreversible necrosis of the forearm flexor m.

Question 13

A pt sustains a fx to the midhumeral shaft. Which nerve may be injured and why?
What are the consequences of damage to this nerve?

Answer 13

The radial nerve, b/c lies in the radial groove in the humeral shaft.
When this nerve is damaged, the fx is not likely to paralyze the triceps b/c of the high origin of the nerves to 2 of its 3 heads.

Question 14

What may be a potential complication of a supra-epicondylar fx? Explain why/how, what is effected?

Answer 14

A fx of the distal part of the humerus , near the supraepicondylar ridges is called a supraepicondylar fx. The distal bone fragment may be displaced anteriorly or posteriorly, and b/c the actions of the brachialis and triceps tend to pull the distal fragment over the proximal fragment, this shortening the limb, and any of the nerves or branches of the brachial vessels related to the humerus may be injured by a displaced bone fragment.

Question 15

What are the consequences of an injury to the musculocutaneous nerve and how would this injury come about? Clinical signs?

Answer 15

In the axilla, tends to be uncommon when the arm is down due to the protected position. This injury tends to occur when by a weapon such as a knife and results in the paralysis of the coracobrachialis (remember runs through the belly of the coracobrachialis). Weak flexion may occur at the GH jt owing to the injury of the musculocutaneous nerve affecting the long head of the biceps brachii and the coracobrachialis.
consequently, flexion of the elbow jt and supination of the forearm are greatly weakened, but are not lost. Weak flexion and supination are still possible, produced by the brachioradialis and the supinator, both of which are supplied by the radial nerve. Loss of sensation may occur on the lateral surface of the forearm supplied by the lateral antebrachial cutaneous nerve, the continuation of the musculocutaneous nerve.

Question 16

What are the consequences of an injury to the radial nerve, how would this injury come about? Clinical signs?

Answer 16

Injury to the radial nerve superior to the origin of its branches to the triceps brachii results in paralysis of the triceps brachii resulting in paralysis of the triceps, brachioradialis, supinator and extensor muscles of the wrist and fingers. Loss of sensation to the skin supplied by this nerve also occurs

When this nerve is injured in the radial groove, the triceps is usually not completely paralyzed, but only weakned b/c only the medial head is affected. However, the muscles in the psterior compartment of the forearm that are supplied by more dista branches of the nerve are paralyzed.
The characteristic clinical sign is wrist drop- an inability to extend the wrist and the fingers at the metacarpalphalangeal jts. Instead the relaxed wrist assumes a partly flexed position owing to unopposed tonus of the flexor muscles and gravity

Question 17

Why is the median cubital vein chosen typically as a site for venipuncture?

Answer 17

b/c of the prominence and accesibility of the veins.
When the most common pattern of superficial veins is present, the median cubital vein is selected. This vein lies directly on the deep fascia, running diagonally from the cephalic vein to the basilic vein of the arm. It crosses the bicipital aponeurosis separating it from the underlying brachial artery and median nerve and providing some protection to these structures. Aponeurosis previously known as the grace Deux (grace of God)tendon b/c of this protection to underlying structures, prevented arterial hemorrhage in the days of blood letting.
A tourniquet placed around the midarm to distend the veins in the cubtial fossa-vein punctured and then the tourniquet is removed so that the vein will not bleed extensively.
The median cubital vein is also the site of the introduction of cardiac catheters to secure blood samples from the great vessels and chambers of the heart. Veins may also be used for coronary angiography

Question 18

What is important to remember about the variation of the veins in the cubital fossa

Answer 18

The pattern of veins in the cubital fossa varies greatly. In approx 20% of people, a median antebrachial vein (medial vein of the forearm) divides into a median basilic vein which joints the basilic vein of the arm and a median cephalic vein which joins the cephalic vein of the arm. In these cases, a clear M formation is produced by the cubital veins.
Important to observe and remember that either the median cubital vein or the median basilic vein, whichever atter is present, crosses superfiically to the brachial artery, from which it is separated by the bicipital aponeurosis. These veins are good for drawing blood, but not for injecting an irritating drug b/c of the danger of injecting it into the brachial artery.
In obese ppl, a considerable amount of fat may overlie the vein.

Question 19

Explain the mechanism of elbow tendinitis/lateral epicondylitis, what are the signs?

Answer 19

painful musculoskeletal condition that may follow repetitive use of the superficial extensor m. of the forearm.
Pain felt over the lateral epicondyle and radiates down the posterior surface of the forearm. Ppl with elbow tendinitis often feel pain when they open a door or lift a glass
Repeated forceful flexion and extension of the wrist strain the attachment f the common extensor tendon producing inflammation of the periosteum of the lateral epicondyle (lateral epicondylitis)

Question 20

Explain the mechanism for Mallet/baseball finger. What are the clinical signs?

Answer 20

sudden severe tension on a long extensor tendon may avulse part of its attachment to the phalanx. The most common result of the injury is mallet or baseball finger. Deformity results from the distal interphalangeal jt suddenly being forced into extreme flexion (hyperflexion)when, for example, a baseball is miscaught or a finger is jammed into the base pad.
These actions avulse or tear away the attachment of the tendon to the base ofthe distal phalanx As a result the person cannot extend the distal interphalangeal jt and the resultant deformity bears some resemblance to a mallet

Question 21

What is the mechanism for an olecranon fx, why is this fx common?,

Answer 21

common because the olecranon is subcutaneos and protrusive.
Typical mechanism is a fall on the elbow combined with sudden powerful contraction of the triceps brachii.
fx olecranon is pulled away by the active and tonic contraction of the triceps and the injury is often considered to be an avulsion fx. b/c of the traction produced bby the tonus of the triceps on the olecranon fragment, pinning is usually required and a cast must be worn for an extended period of time.

Question 22

Discuss the synovial cyst of the wrist, where does this most commonly appear, clinical signs?

Answer 22

Sometimes a non tender cystic swelling appears on the hand, most commonly on the dorsum of the wrist. Usually the cyst is the size of a small grape, but it varies and may be as large a s aplum. The thin walled cyst contais clear mucinous flud. The cause of the cust is unknown, but it may result from mucoid degeneraton. Flexion of the wrist makes the cyst enlarge and it may be painful.
Clinically this type of swelling is called a ganglion (swelling or knot). Anatomically, a ganglion reffers to a colection of nerve cell bodies. Synovial cysts are close to and often communucate with the synovial sheaths on the dorsum of the wrist. The distal attachment of the ERCB tendon is another common site for the cyst to appear. A cystic swelling of the common flexore synovial sheath on the anterior aspect of the wrist can enlarge enough to produce compression of the medan nerve by narrowing the carpal tunnel (carpal tunnel syndrome, which produces pain and paresthesia in the sensory distribution of the median nerve and clumsiness of finger movements.

Question 23

What is the difference with the radial and ulnar arteries in a case of high division of the brachial artery, where will they begin?

Answer 23

Sometimes the brachial artery divides at a more proximal level than usual. In this case, the ulnar and radial arteries begin in the superior or middle portion of the arm and the median nerve passes between them, he musculocutaneous and median nerves commonly communicate

Question 24

What are the consequences of an injury to the median nerve, clinical signs? mechanism of injury?

Answer 24

severed in the elbow region, flexion of the proximal interphalangeal jts of the 1-3 digits are lost and flexion f the 4th and 5th digits is weakned. Flexion of the distal interphalangeal kts of the 2nd and 3rd fingers is also lost.
Flexion of the distal interph jts of the 4th and 5th digits is not effected b/c the medial part of the FDP producing these movements is supplied by the ulnar nerve.
The ability to flex the metacarpoph jts of the 2nd adn 3rd digits affected b/c the digital branches of the median nerve supply the 1st and 2nd lumbricals. -When a person attempts to make a fist, the 2nd and 3rd fingers will remain partially extended (hand of benediction).
Thenar muscle function will be lost.
When the anterior interosseous nerve is injured, the thenar m are unaffected, but paresis of the FDPand flexor pollicis longus occurs. When the person atempts to make the ok sign, opposing the tip of the thumb and index finger in a circle, a pinch posture of the hand will result instead owing to the abscence of flexion of the interph jt of the index finger.

Question 25

Explain the mechanism for pronator syndrome

Answer 25

nerve entrapment sndrome, caused by compresion of the median nerve near the elbow. Nerve may be compressed between the heads of the pronator teres as a result of trauma, muscular hypertrophy or fibrous bads
Individuals with this syndrome are first seen clinically with pain and ttp in the proximal aspect of the anterior forearm and hypesthesia (dec senstaion)of palmar aspect of the radial three and half dig and adj palm. sx often follow activities that involve repeated pronation

Question 26

What is clinically important to know about potential communications between the median and ulnar nerves

Answer 26

occasionally, communications occur between the median and the ulnar nerves in teh forearm.
Even with a complete lesion of the median nerve, some muscles may not be paralyzed which may lead to an erroneous conclusion that the median nerve has not been damaged

Question 27

John doe presents with minor weakness with forearm flexion, weakness of supination, and loss of sensation to the posterior corearm and dorsum of hand. Which nerve is likely to be injured?

Answer 27

radial

Question 28

Explain the mechanism for an ulnar nerve injury at the elbow and in the forearm. Common locations to injure the nerve?

Answer 28

injuries usually occur in 4 places:
1. post to the medial epicondyle
2. in the cubital tunnel formed by the tendinous arch connecting the humeral and ulnar heads of the FCU
3. at the wrist
4. in the hand.
Occurs most commonly where the nerve passes post to the medial epicondyle of the humerus. The injury results when the medial part of the elbow hits a hard surface, fx the medial epicondyle (funny bone)
Any lesion superior to the medial epicondyle will produce paresthesia of the median part of the dorsum of the hand.
Compression of the ulnar nerve at the elbow (cubital tunnel syndrome
ulnar nerve injury can result in extensive motor and sensory loss to the hand. An injury to the nerve in the distal part of the forearm denervates most intrinsic hand m. Power of wrist adduction is impaired and when an attempted is made to flex the wrist jt, the hand is drawn to the lateral side by the FCR-which is supplied by the median nerve. in the absence of the balance provided by the FCU. After an ulnar injury, the person has difficulty making a fist b/c in the absence of opposition, the MCP jts become hyperextended and they cannot flex the 4th and 5th digits at the distal IP jts when trying to make a fist.
Furthermore, the person cannot extend the interphalangeal jts when trying to straighten the fingers, This characteristic appearance of the hand resulting from a distal lesion of the ulnar nerve is known as claw hand-results from atrophy of the interosseous m of the hand supplied by the ulnar nerve. the claw is produced by unopposed action of the extensors and FDP.

Question 29

What is the cause for cubital tunnel syndrome, which nerve is effected?

Answer 29

The ulnar nerve becomes compressed in the cubital tunnel formed by the tendinous arch joining the humeral and ulnar heads of attachment of the FCU. The signs and sx of cubital tunnel syndrome are the same as an ulnar nerve lesion in the ulnar groove on the post aspect of the medial epicondyle.

Question 30

Discuss the mechanism for a radial nerve injury in the forearm ( superficial or deep branches)

Answer 30

usually injured by a fx in the humeral shaft
injury is proximal to the motor branches to the long and short extensors of the wrist from the common radial nerve, and so wrist drop is the primary clinical manifestation of an injury at this level
Injury to the deep branch of the radial nerve may occur when wounds of the post forearm are deep and penetrating. Severeance of the deep branch fresults in an inability to extend the thumb and teh MCP jts of the ther digits. Thus the integrit of the deep branch may be tested by asking the person to extend the MP joints while the examiner provides resistance. If the nerve is intact, the long extensor tendons should appera prominently on the dorsum of the hand, confirming that the extension is occurring at the MP joints rather than at the IP jts (movements under the control of other nerves).
Loss of sensation does not occur b/c the deep branch of the radial nerve is entirely muscular and articular in distribution.
When the superficial branch of the radial nerve, a cutaneous nerve, is severed, sensory loss is usually minimal. Commonly, a coin shaped area of anesthesia occurs distal to the bases of the 1st and 2nd metacarpals. The reason the area of sensory loss is less than expected is the result of the considerable overlap from cutaneous branches of the median and ulnar nerves.

Question 31

What is Dupuytren contracture of the palmar fascia? What does this finding indicate?

Answer 31

dz of the palmar fascia resulting in progressive shortening, thickening, and fibrosis of the palmar fascia and aponeurosis. pulls the 4th and 5th fingers into partial flexion at the MCP and proximal interphalangeal jts.
Frequently bilateral and is seen in soe men>50 yrs of age
Cause unknown, evidence points to a hereditary predisposition.
dz first manifests as a painless nodular thickening of the palmar aponeurosis that adhers to the skin. Gradually, a progressive contracture of the longitudinal bands produces raised ridges in teh palmar skin that extend from the proximal part of the hand to the base of the 4th and 5th fingers. Treatment involves surgical excision of the fibrotic parts of the palmar fascia to free the fingers

Question 32

Where will hand infections typically appear?

Answer 32

Typically will appear on the dorsum of the hand where the fascia is thinner. Palmar fascia is thick and strong. The potential fascial saces of the palm are important ecause they may become infected. the fascial spaces determine the extend and direction of the spread of pus formed by these infections
Depending on the site of the infection, pus will accumulate in the thenar, hyothenar, midpalmar, or adductor compartments. Abx therapy has made infectijons that spread beyond one of these fascial compartments rare, however, an untreated infection can spread throughout the carpal tunnel and into the forearm, anterior to the pronator quadratus and its fascia.

Question 33

Explain the mechanism for tenosynovitis, clinical signs?

Answer 33

Injuries such as a puncture of a finger by a rusty nail can cause infection of the digital synovial sheaths. When inflammation of the tendon and synovial sheath occurs, known as tenosynovitis, the digit swells and movement becomes painful. b/c the tendons of the 2nd, 3rd, and 4th fingers nearly always have separate synovial sheaths, the infection is usually confined to the infected finger. If the infection is ntreated, howveer, the proximal ends of these sheaths rupture allowing the infection to spread to the midpalmar space.
b/c the synovial sheath of the little finger is usually continuous with the common flexor sheath, tenosynovitis in this finger may spread to the common sheath and this through the palm and carpal tunnel t the anterior forearm, draining into the space between the pronator quadratus and the overlying flexor tendons.

Question 34

For some surgical procedures involving complicated hand surgeries ,it is necessary to compress the brachial artery and its brancehs proximal to the elbow. Why is this needed and what does it prevent?

Answer 34

Needed because the bleeding is profuse from the palmar area when the arterial arches are lacerated-bleeding from both ends. Compress to obtain a bloodless surgical operating field during complicated hand surgeries. Procedure prevents blood from reaching the ulnar and radial arteries through the anastomoses around the elbow

Question 35

Explain the mechanism for carpal tunnel syndrome

Answer 35

results from any lesionn that significantly reduces the size of the carpal tunnel. or increases the size of the nine structures or their coverings that pass through it. (inflammation of the synovial sheaths). Fluid retention, infection and excesive exercise of the fingers (overuse) may cause swelling of the tendons or their synovial sheaths. The median nerve is the most sensitive structure in the tunnel and has 2 sensory branches that supply the skin of the hand (hence paresthesia), hypoasthesia (dec sensation) or anesthesia (absence of sensation) may occur in the lateral 3 digits. Palmar cutaneous branch of the median nerve arises proximal to, and does not pass through, the carpal tunnel; thus senseation in the central palm remains unaffected. Progressive loss of corrdination and strength f the thumb (owing to weakness of the APB and opponens pollicis) may occur if the cause of the compression is not alleviated.
Individuals with carpal tunnel are unable to oppose their thumbs-they have difficulty buttoning a shirt or blouse as well as gripping objects like a comb.
As the condition progresses, sx and sensory changes begin to radiate into the forearm and axilla.
Sx can be reproduced by compression of the median nerve with your finger at the wrist for approx 30 sec.
Surgery-carpal tunnel release may be necessary to cure.

Question 36

What are the consequences of trauma to the median nerve? when is this injury often seen?

Answer 36

Laceration of the wrist-often seen in attempted suicides by wrist slashing.
Results in paralysis of the thenar muscles and first 2 lumbricals.-Opposition of the thumb is not possible, and fne control movements of the 2nd through 3rd diits are impaird. Sensation lost over the thumb and adjacent 2 and half fingers.
The APL and adductor pollicis may imitate opposition, although ineffective.
nerve injury at the elbow from a perforating wound in the elbow region results in loss of felxion of the prix and distal IP jts of the 2nd and 3rd digits. Ability to flex the MCP jts of these fingers is also affected b/c the branches of the median nerve supply the 1st and 2nd lumbricals.

Question 37

Explain Ulnar canal syndrome (Guyon tunnel syndrome)

Answer 37

Compression of the ulnar nerve may ccur at the wrist where it passes between the pisiform and the hook of hamate. the depression between these bones is converted by the pisohamate lig into an osseofibrous tnnel, the ulnar canal (Guyon tunnel). Ulnar canal syndrome is manifest by hypoesthesia in the medial one and half fingersand weakness of the intrinsic muscles of the hand.
Clawing of the 4th and 5th fingers (hyperextensionat the MCP jt with flexion at the prixial IP jointmay occur, but in contradistiction, to proximal ulnar nerve injury, their ability to flex is unaffected and there is no radial deviation of the hand.

Question 38

What is handlebar neuropathy? what does it indicate?

Answer 38

People who ride long distances on bicycles with their hands in an extended position against the had grips put pressure on the hooks of their hamates which compresses their ulnar nerves. This type of nerve compression, which has been called handlebar neuropathy results in snsory loss on the medial side of the had and weakness of the intrinsic hand muscles

Question 39

explain how a radial nerve injury can cause a major hand disability, despite the fact that the radial nerve does ntot itself supply any muscles in the hand.

Answer 39

The characteristic handicap is an inability to extend the wrist resulting from paralysis of the extensor m of the forearm, all of which are innervated by the radial nerve. The hand is flexed at the wrist and lies flaccid, a condition known as wrist drop. The fingers of the relaxd hand also remain in the flexed postion at the MCP jts
The interphalangeal joints can be extended weakly through the action of the iintact lumbricals and interossei, which are supplied by the median and ulnar nerves.
The radial nerve has only a small area of exclusive cuanoeous supply on the hand. thus the extent of anesthesia is minimal, even in serious radial nerve injuryies and is usually confined to a small area on the lateral part of the dorsum of the hand.

Question 40

What are the 3 ways that metastasis of CA can occur?

Answer 40

1. Direct seeding of serous membranes of body cavities
2. lymphogenous spread (via lymph vessels)
3. hematogenous spread (via blood vessels

Question 41

explain the mechanism for lymphogenous spread of CA

Answer 41

most common route for dissemination of carcinomas, the most common type of CA. Cells loosened from the primary CA site eenter and travel via lymphatics. The lymph-borne cells are filtered through and trapped by lymph nodes which thus become secondary (metastatic)CA sites
The pattern of cancerous lymph node involvement follows the natural routes of lymph drainage- when removing a potential metastatic tumor, surgeons stage the metastasis, determine the degree to which CA has spread- by removing and examining lymph nodes that receive lymph from the organ or region in the order the lymph usually passes through them.
Critical to known backwards and forwards what nodes are affected when a tumor is identified in a certain site or organ and the order in which they receive lymph and also to determine likely sites of promaryCA sites (sources of metastasis when an elarged node is detected.
Cancerous nodes enlarge the tumor cells within them increase; however, unlike swollen infected nodes, cancerous nodes are not usually painful when compressed

Question 42

Explain the mechanism of hematogenous spread of CA (via blood vessels)

Answer 42

Hematogenous spread of CA is the most common route for the metastasis of the less common (but more malignant) sarcomas )connective tissue cancers. Because veins are more abundant and have thinener walls that offer less resistance, metastasis occurs more often by venous than arterial routes. Since the blood borne cells follow venous flow, the liver and lungs are the most common sites of secondary sarcomas. Typically, the treatment or removal of a primary tumor is not difficult, but the treatment or removal of all the affected lymph nodes or other secondary (metastatic) tumors may be impossible to remove,

Question 43

what occurs in lymphangitis and lymphadenitis

Answer 43

secondary inflammations of lymphatic vessels and lymph nodes that may occur when the lymphoid system is involved in chemical or bacterial transport after severe injury or infection. The lymphatic vessels, not normally evident, may become painfully enlarged
The condition is potentially dangerous b/c the uncontained infection may lead to septicemia (blood poisoning).

Question 44

What occurs in lymphedema

Answer 44

Lymphedema is a localized type of edema which occurs when lymph does not drain from an area of the body. For example, if CA lymph nodes are surgically removed from the axilla, (compartment) superior to the armpit), lymphedema of the limb may occur. Solid cell growths may permeate lymphatic vessels and form minute cellular emoboli (plugs), which may break free and pass to regional lymph nodes. In this way, further lymphogenous spread to other tissues and organs may occur.

Question 45

Why is understanding the lymphatic drainage of the breast important? What is the path of drainage/which lymph nodes does it drain into first?

Answer 45

Significant practical importance in predicting the metastases of dispersal of carcinomas, which are malignant , usually adenocarcinomas (glandular CA)arising from the epithelial cells of the lactiferous ducts in the mammary gland lobules. Metastatic CA cells that enter a lymphatic vessel usually pass through two or 3 groups of lymph nodes before entering the venous system. Cells lodge in the nodes roduccing nests of tumor cells (metastases). Abundant communication between lymphatic pathways and among axillary, cervical and parasternal nodes may also cause metastases from the breast to develop in teh supraclavicular lymph nodes, the opposite breast or the abdomen. b/c most of lymphatic drainage of the breast is to the axillary lymph nodes, they are the most common site of metastasis from a breast CA. Enlargement of these palpable nodes suggests the possibility f rest CA and may be key to early detection, however the absence of enlarged axillary lymph nodes is no guarantee that metastasis from a breast CA has not occurred. The malignant cells may have passed to other nodes, such as the infraclavicular and supraclavicular nodes.

Question 46

What causes the peau de orange sign? what does this indicate?

Answer 46

Interference with the lymphatic drainage by CA may cause lymphedema, (edema or excess fluid in the subcutaneous tissue) which in turn may result in a deviation of the nipple and a thickened leather like appearance of the skin. Prominent puffy skin between dimpled ports gives it an orange peel apperance- peau de orange sign. Larger dimples that are fingertip size or bigger, result from cancerous invasion of the glandular tissue adn fibrosis (firbrous degeneration

Question 47

How can breast CA travel through the veins and what structures are at risk? Specifically the posterior intercostal veins

Answer 47

The posterior ntercostal veins drain into the azygos/hemi-azygos system of veins alongside the bodies of the vetebrae- and communicate with teh internal vertebral venous plexus surrounding the spinal cord. CA cells can also spread from the breast by these venous routes to the vertebrae and from there to the cranium and the brain.

Question 48

What structures are at risk with the spread of CA to adjacent tissues?

Answer 48

CA also spreads by contiguity(invasion of the adj tissue). When breast CA invades the retromammary space attach to or invade the pectoral fascia overlying the pectoralis major or metastasize to the interpectoral nodes, the breast elevates when the muscle contracts. This movement is a clinical sign of advanced CA of the breast and to observe this upward movement, the physician will have the pt place her hands on her hips and press while pulling the elbows forward to tense the pectoral muscles.

Question 49

Where are surgical incisions typically made on the breast and why?

Answer 49

typically made in teh inferior reast quadrants when possible because these quadrants are less vascular than the superior ones and the transition between the thoracic wall and the breast is most abrupt inferiorly, producing a line, crease or deep skin fold- the inferior cutaneous crease. Incisions made along this crease will be less evident and may be hidden by overlap of the breast. Incisions that must be made near the areola or on the breast itself are usually directed radially to either side of the nipple (larger tension lines run transversely here or circumferentially).
The mastectomy is not as common as it once was as a treatment for breast CA. In a simple mastectomy, the breast is removed down to the retromammary space.
Radical mastectomy- a more extensive surgcal procedure involving the removal of the breast, pec muscles, fast, fascia and as many lymph nodes as possible in the axilla and pectoral region.
In current practice often only the tumor and surrounding tissues are removed- a lumpectomy or quadrantectomy

Question 50

What is polymastia?

Answer 50

Suernumary breasts
Consist of only a rudimentary nipple and areola which may be mistaken for a mole/nevus until they change pigmentation with normal nipples during pregnancy. Glandular tissue may also be present and further develop with lactation.
These small supernumary breasts may appear anywhere along a line extending from the axilla to the groin. The location of embryonic mammary crest(milk line) from which the breasts develop in animals with multiple breasts. There may be no breast development (amastia) or there may be a nipple with no glandular tissue.

Question 51

What is polythelia?

Answer 51

Accessory nipples which may occur superior or inferior to the normal paif, occasionally deveoping in the axillary fossa or anterior abd wall.

Question 52

How does breast CA typically present in males

Answer 52

Approx 1.5% of breast CA occur in men. As in women, the CA usually metastasizes to axillary lymph nodes but also to the bone, pleura, lung, liver and skin. Affects approx 1000 men per yr in the US. A visible and or palpable subareolar mass or secretion from a nipple may indicate a malignant tumor. Breast CA in males tends to infiltrate the pectoral fascia, pec maj and apical lymph nodes in the axilla. Although uncommon, the consequences are serious because they are frequently not detected until extensive metastases have occurred.

Question 53

What is gynecomastia

Answer 53

Slight temporary enlargment of the breasts is a normal occurence in males at puberty from ages 10-12. Breast hypertrophy in males after puberty is relatively rare and may be age or drug related.
For example, after treatment with dethylstilbestrol for prostate CA. Can result from an imbalance between estrogenic and androgenic hormones or from a change in the metabolism of sex hormones or from a change in the metabolism of sex hormones by the liver. Thus a finding of gynecomastia should be regarded as a sx and an evaluation must be initiated to rule out important potential causes sych as suprarenal or testicular CA. Approx 40% of post-pubertal males with Klinefelter’s XXY trisomy have gynecomastia.

Question 54

Discuss the arterial anastamoses around the scapula and the importance of this feature

Answer 54

Many arterial anastomoses occur around the scapula. several vessels join to form networks on the anterior and posterior surfaces of the scapula. the dorsal scapular, suprascapular and (via the circumflex scapular) subscapular arteries. The importance of having these collateral circulation routes is made apparent when ligation of a lacerated subclavian or axillary artery is necessary. For example, the axilllary artery may have to be ligated between the 1st rib and subscaular artery and in ther cases the vascular stenosis of the axillary artery ma result from an atherosclerotic lesion that causes reduced blood flow. In either case, the direction of blood flow in the subscapular artery is reversed enabling blood flow to reach the third part of the axillary aertery. Note that the subscapular artery receives blood through several anastomoses with the suprascapular artery, dorsal scapular artery and intercostal arteries. Slow occlusion of the axillary artery (resting from dz or trauma) often enables sufficient collateral circulation to develop, preventing ischemia (loss of blood supply). Sudden occlusion usually does not allow sufficient time for adequate collateral circulation to develop and as a result, there is an inadequate supply of blood to the arm, forearm and hand. While potential collateral pathways (peri-articular anastomoses) exist around the shoulder joint proximally, and the elbow joint distally, surgical ligation of the axillary artery between the origins of the subscapular artery and the profunda brachii artery will cut off the blood supply to the arm because the collateral circulation is inadequate

Question 55

What is the consequence of compression of the axillary artery?

Answer 55

The axillary artery can be palpated in the inferior part of the lateral wall of the axilla. Compression of the third part of this artery against the humerus may be necessary when profuse bleeding occurs- resulting from a stab or bullet-wound in the axilla. If compression is required at a more proximal site, the axillary artery can be compressed at its origin ( as the subclavian artery crosses the first rib) by exerting downward pressure in the angle between the clavicle and the inferior attachment of the sternocleidomastoid.

Question 56

What is the consequence of an aneurysm to the axillary artery and how does this often occur?

Answer 56

The first part of the axillary artery may enlarge and compress the trunks of the brachial plexus casing pain and anesthesia (loss of sensation) in the areas of the skin supplied by the affected nerves. Aneursym of the axillary artery may occur in baseball pitchers and football quarterbacks because of their rapid and forceful arm movements.

Question 57

What is the consequence of an injury to the axillary vein? Why is the vein at risk?

Answer 57

Wounds int the axilla often involve the axillary vein because of its large size and exposed position. When the arm is fully abducted, the axillary vein overlaps the axillary artery anteriorly. A wound in the proximal part of the axillary artery anteriorly. A wound in the proximal part of the axillary vein is particularly dangerous, not only because of profuse bleeding, but also because of the risk of air entering it and producing air emboli in the blood.

Question 58

What is the role of the axillary vein in the subclavian vein puncture

Answer 58

Subclavian vein puncture, in which a catheter is placed into the subclavian vein has become a common clinical procedure. The axillary vein becomes the subclavian vein as the first rib is crossed. Because the needle is advanced mediallyto enter the vein as it crosses the rib, the vein actually punctured (the point of entry)in a subclavian vein puncture is the terminal part of the axillary vein. However the needle tip proceeds into the lumen of the subclavian vein almost immediately. Thus it is clinically significant that the axillary vein lies anterior and inferior (superficial) to the axillary artery and the parts of the brachial plexus that surround the artery at this point.

Question 59

What are potential causes of axillary lymph node enargement?

Answer 59

1. an infection in the upper limb can cause the axilllary nodes to enlarge and become tender and inflamed- a condition called lymphangitis (inflammation of the lymphatic vessels). The humeral group of nodes is usually the first to be involved.
   Lymphangitis is characterized by the development of a warm, red tender streak of the skin of the limb. Infections in the pectoral region and breast, including the superior part of the abdomen, can also produce enlargement of the axillary nodes. In metastatic CA of the apical group, the nodes often adhere to the axillary vein, which may necessitate excision of part of this vessel. Enlargement of the apical nodes may obstruct the cephalic vein superior to the pectoralis minor.

Question 60

Which 2 nerves are at risk during an axillary node dissection?

Answer 60

During surgery, the long thoracic nerve to the serratus anterior is identified and maintained against the thoracic wall. - if cut=winged scapula.
If the thoracodorsal nerve to the latissimus dorsi is cut, medial rotation and adduction of the arm area weakened, but deformity does not result.
sometimes if the nodes around this nerve are obviously malignant, sometimes the nerve has to be sacrified as he nodes are resected to increase the likelihood of complete removal of all malignant cells.

Question 61

Discuss some possible variation of the brachial plexus that may be encountered

Answer 61

Variations in teh brachial plexus are common. In addition to the 5 anterior rami, that form the roots of the brachial plexus , small contributions may be made by the anterior rami of C4 or T2. When the superior-most root (anterior ramus) of the plexus is C4 and the inferiormost root is C8, it is a prefixed brachial plexus. Alternately when the superior root is C6 and the inferior rootis T2, it is a post fixed brachial plexus. In the latter type, the inferior trunk of the plexus may be compressed the 1st rib, prodycing neurovascular sx in the upper limb. Variations may also occur in the formations of trunks , divisiojns, ,and cords. In the origin and/or combination of branches; and in the relationship to the axillary artery and scalene muscles. For example, the lateral or medial cords may receive fibers from anterior rami inferior or superior to the usual levels respectively. In some individuals, trunk divisions or cord formations may be absent in one or other parts of the plexus, however, the makeup of the terminal branches is unchanged. Because each peripheral nerve is a collection of nerve fibers bond together by connective tissue, it is understandable that the median nerve, for instance may have up to 2 medial roots instead of one(nerve fibers are simply grouped differently) This results from the fibers of the medial cord of the brachial plexus dividing into the three branches, two forming the median nerve and the third forming the ulnar nerve. Sometimes it may be more confusion when the 22 medial roots are completely separate. However, understand that although the median nerve may have two medial roots the components of the nerve are the same(impulses arise from the same place and reach the same destination whether they go through one or two roots.

Question 62

What are common injuries to the brachial plexus? Consequences?

Answer 62

Injuries to the brachial plexus affect movements and cutaneous sensations in the upper limb. Dz, stretching and wounds in the lateral cervical region (posterior triangle) of the neck or in the axilla may produce brachial plexus injuries. Signs and sx depend on the part f the plexus involved.
Injuries can result in paralysis and anesthesia. Testing the person’s ability to perform these movements assesses the the degree of paralysis.
In complete paralysis, no movement is detectable.
In incomplete paralysis, not all m are paralyzed, therefore a person can move, but the movements are weak compared with those on the normal side. Determining the abilityz of the person to feel pain

Question 63

What is the effect of an injury to the superior portion of the superior brachial plexus? Common mechanisms for this injury?

Answer 63

If the superior portion of the brachial plexus is injured (C5 and C6) usually result from an excessive increase in the angle between the neck and shoulder. Can occur in a person who is thrown from a motorcycle or a horse and lands on the shoulder in a way that widely separates the neck and the shoulder. When thrown, a person’s shoulder often hits something and stops, but the head and trunk continue to move. This stretches or ruptures superior parts of the brachial plexus or avulses (tears) the roots of the plexus from the spinal cord.
Injury is apparent by the characteristic position of the limb (waiter’s tip position). in which the limb hangs by the side in medial rotation. Upper brachial plexus injuries also occur in a neonate when excessive stretching of the neck occurs during delivery, paralysis of the muscles of the shoulder and arm supplied by the C5 and C6 spinal nerves occurs: deltoid, biceps, and brachialis.
Usual clinical appearance is an upper limb ith an adducted shoulder, medially rotated arm and extended elbow.
Lateral aspect of the forearm also experiences some loss of sensation.

Question 64

What is acute brachial plexus neuritis?

Answer 64

is a neurological disorder of unknown cause that is characterized by the sudden onset of severe pain, usually around the shoulder. Typically, pain begins at night and is followed by muscle weakness and sometimes muscular atrophy. Inflammation of the brachial plexus is often preceded by some event (URI, vaccination, or non specific trauma).

Question 65

When do injuries typically occur to the inferior brachial plexus

Answer 65

Less common , may occur when the upper limb is suddenly pulled superiorly for example, when a person grasps something to break a fall or a baby’s upper limb is pulled excessively during delivery. These events may avulse the roots of the spinal nerves from the spinal cord. The short muscles of the hand are affected and a claw hand result.

Question 66

What is a brachial plexus block?

Answer 66

Injection of an anesthetic soln into or immediately surrounding the axillary sheath interrupts conduction of impulses of peripheral nerves and produces anesthesia of the structures supplied by the branches of the cord and plexus. Sensation is blocked in al the deep structures of the upper limb and the skin distal to the middle of the arm, Combined with an occlusive tourniqust technique to retain the anesthetic agent, this procedure enables surgeons to operate on the uper limb without using general anesthetic.

Question 67

How is vertebral body osteoporosis detected and what is the cause? Where are the most affected areas

Answer 67

detected during routine radiographic studies. Osteporosis results from a net demineralization of the bones caused by a disruption of the normal balance of CA deposition and resorption. As a result, the quality of bone is reduced and atrohy of the skeletal tissue curs. Most affected areas are the neck and femur, the bodies of the vertebrae and the metacarpals (bones of the hands) and the radius. These bones become weakened and brittle and are subject to fx. Evident as diminished radiodensity of the trabecular (spongy) bone of the vertebral bodies causing the thinned cortical bone to appear relatively prominent. Osteoporosis especially effects the horizontal trabeculae of the trabecular bones of the vertebral body. Consequently, vertical stripping may become apparent, reflecting the loss of the horizontal supporting trabeculae and thickening of the vetical struts.
Occurs in all vertebrae, most common in the T vert and common finding in post menopausal females.

Question 68

What is a laminectomy of the spine and what is it performed.

Answer 68

The surgical exision of one or more spinous processes and the adjacent supporting vertebral laminae in a particular region of the vertebral column is called a laminectomy. The term is also commonly use to denote removal of most of the vertebral arch by transecting the pedicles. Laminectomies are performed surgically (or anatomically in the dissection lab) to gain access to the vertebral canal, providing posterior exposure of the spinal cord (if performed above the L2 level and or the roots of specific spinal nerves. Surgical laminectomy is often performed to relieve pressure on the spinal cord or nerve roots caused by a tumor, herniated IV disc or bony hypertrophy.

Question 69

Why are cervical vertebrae more prone to dislocation

Answer 69

because of their more horizontally oriented articular facets, the c vertebrae are less tightly interlocked than other vertebrae. The cervical vertebrae “stacked like coins”, can be dislocated in neck injuries with less force than is required to fx them Bc of the large vertebral canal in the cervical region, slight dislocation can occur here without damaging the spinal cord. Severe dislocations or dislocations combined with fx injury to the spinal cord. If dislocation does not result in facet jumping with locking of the displacd articular processes, the cervical vertebrae may self reduced (spip back into place)so that a radiograph may not indicate that the cord has been injured. An MRI howveer, would reveal the resulting soft tissue damage.

Question 70

Mechanism of fx/dislocation of atlas

Answer 70

Because the taller side of the lateral mass is directed laterally, vertical forces (as would result from striking the bottom of a pool in a diving accident) compressing the lateral masses between the occipital condyles and the axis drive them apart fx one or both of the anterior or posterior arches.
If the force is sufficient, rupture of the transverse lig that links them will also occur. Resulting Jefferson or burst fx in itself does not necessarily result in a spinal cord injury, b/c the dimensions of the bony ring actually increase. Spinal cord injury is more likely however, if the transverse lig has also been ruptured.

Question 71

What is the mechanism for fx of C2/axis? What is this fx commonly called?

Answer 71

Fx of the vertebral arch of the axis (C2) are one of the most common injurues of the cervical vertebrae (up to 40%). Usually the fx occurs in the bony column formed by the superior and inferior articular processes of the axis, the pars interarticularis. a fx in this location called a traumatic spondylosis of C2 usually occurs as a result of hyperextension of the head on the neck, rather than combined hyperextension of the head and neck, which may result in whiplash.
Such mechanism was used to execute criminals by hanging- hangman’s fx- knot was placed directly under the chin before the body was suddenly dropped on its length through the gallows floor
In more severe injuries the body of C2 is displaced anteriorly with respect to the body of the C3 vertebrae. With or without such subluxation (incomplete dislocation) of the axis, injury of the spinal cord and/or the brain stem is likely. sometimes resulting in quadriplegia or death.
Fx of the dens is also common in C2 injuries.
which may result from a horizontal blow to the hea or aas a complication of the osteopenia (athological loss of bone mass).

Question 72

Discuss the cause of lumbar spinal stenosis, clinical signs

Answer 72

describes a stenotic (narrow) vertebral foramen in one or more lumbar vertebrae. This condition may be a hereditary anomaly that can make a person more vulnerable to age-related degenerative changes such as IB disc bulging. Lumbar spinal nerves increase in size as the vertebral column descends, but paradoxically, the IV foramina decrease in size. Narrowing is usually maximal at the level of the IV discs. However, stenosis of a lumbar vertebral foramen alone may cause compression of one ore more spinal nerve roots occupying the inferior vertebral canal. Surgical treatment of lumbar stenosis may consist of decompressive laminectomy
When IV disc protrusion occurs in a pt with spinal stenosis, it further compromises a vertebral canal that is already limited as does arthritic proliferation and lig degeneration.

Question 73

Describe the mechanism for an injury to the coccyx

Answer 73

Abrupt fall onto the buttocks may cause a painful subperiosteal bruising or fx of the coccyx, or a fx–dislocation or the sacrococcygeal jt. Displacement is common and surgical removal of the fx bone may be required to relieve the pain. An especially difficult childbirth occasionally injures the mother’s coccyx. A troublesome syndrome, coccygodyna often follows coccygeal trauma; pain relief is commonly difficult

Question 74

What causes spina bifida?

Answer 74

Spina bifida occulta- when the neural arches of L5/S1 fail to develop normally and fuse posterior to the vertebral canal. This bony defect, present in up to 24% of the population occurs in the vertebral arch of L5/S1. This defect is concealed by the overlying skin, but its location is often indicated by a tuft of hair.
Most ppl with spina bifida occulta have no back problems. When examining a newborn, adjacent vertebrae should be palpated in sequence to be certain the vertebral arches are intact and continuous fro the cervical to the sacral regions.
In spina bifida cystica, one or more vertebral arches may fail to develop completely and this is often associated with herniation of the meninges. Neurological sx are usually present in severe cases of meningomyelocele (paralysis of the limbs and disturbances of the bladder and bowel control). Sever forms of spina bifida result from neural tube defefcrts, such as defective closure of the neural tube during the 4th week of embryonic development.

Question 75

What is the mechanism for herniation of IV disc? Which direction does the disc typically herniate?

Answer 75

IV discs in young persons are strong, usually so strong that the vertebrae often fx during a fall before the discs will rupture. Furthermore, the water contect of their nuclei pulposi is high giving them great turgor. However, violent hyperflexion of the vertebral column may rupture a IV disc and fx the adj vertebral bodies.
Flexion of the vertebral column usually produces compression anterioly and stretching or tension posteriorly, squeezing the nucleus pulosus further posteriorly toward the thinnest part of the anulus fibrosis.
If the anulus fibrosis has degenerated, the nucleus pulosus may hernate into the vertebral canal and compress the spinal cord or the nerve roots of the cauda equina.
A herniated IV disc is inappropriately called a slipped disc by some.
herniations usually extend posterolaterally where the anulus firbosus is relatively thin and does not receive support from either the post or the anterior long ligaments. Also more likely to be symptomatic because of the proximity of hte spinal nerves.
Chronic pain resulting from compression of the spinal nerve roots by the herniated disc is usually referred pain perceived as coming from the area(dermatome supplied by that nerve.
Because the I discs are larges in the lumbar and lubosacral region, wehere movements are consequently greater, posterolateral herniations of the nucleus pulposis are most common here.

Question 76

What is the cause for sciatica? How can a test be performed to determine if sciatica is present?

Answer 76

a disc herniation in the lumbar region compressing the L 5, S1 nerve, pain radiating down the lower back and hip into teh back of teh thigh and into the leg.
Any maneuver that stretches the sciatic nerve, such as flexing the thigh with the knee extended (straight leg raise test) may produce or exacerbate sciatic pain.

Question 77

A 3-year-old girl is brought to the emergency room holding her right arm with the elbow flexed and the forearm pronated. She refuses to move her arm and complains her elbow “hurts a lot.” Her mother reports they were holding hands and running in the park when the child tripped. The mother pulled on the child’s hand to prevent her from hitting the ground. Given the nature of this injury and the age of the patient, what structure is most likely damaged?

Answer 77

The anular ligament-
The anular ligament of the radius encircles and holds the head of the radius in the radial notch of the ulna. This ligament enables pronation and supination of the forearm. However, the head of the radius can be pulled distally out of this anular ligament resulting in a subluxation or dislocation of the radial head, which is frequently called “nursemaid’s elbow.” This injury is often seen in children, particularly girls, between the ages of 1 to 3 years old. It occurs when an extended arm is pulled, commonly during a fall, and the individual holding the hand does not let go, as reported in this case. Subluxation and dislocation of the radial head are also seen when the child is swinging while being held by the hands