Musculoskeletal-Anatomy part

Question 1

Arm abduction muscles mnemonic?

Answer 1

Stop Doing this SarAh!
Stop—> Supraspinatus- Suprascapular Nerve
Doing–> Deltoid- Axillary
This–> Trapezius- Accessory
Sarah–> Serratus anterior- Long thoracic.

Their nerve supply mnemonic is SAXAC-LT.

Question 2

Internal and external rotators of the arm?

Answer 2

Instagram per sub latte hein, per external duniya mein sab inferior aur minor.
Internal rotation–> subscapularis, lattismus dorsi
External rotation–> Infraspinatus, Teres Minor.

Question 3

For nerves, first do axillary, then Radial, then Ulnar!

Answer 3

Axillary—> It is axillarating to do surgery of neck, at anterior location and deal Abdullah.
(Means axillary nerve can be damaged at surgical neck of humerus, anterior dislocation of shoulder joint and innervates deltoid which is responsible for 15-90 abduction)

So for axillary, you need to remember that it is a branch of the posterior cord of the brachial plexus (C5,C6)—> It moves underneath subscapularis and then goes below the glenohumeral joint (That’s why damaged in anterior dislocation of shoulder joint), enters the quadrangle space (The square formed between teres major, teres minor, Triceps, humerus bone)–> uss space sey yeh humerus ki srugical neck kay around chipak ker arm kay anterior comparment mein chali jaati hai. (Hence, surgical neck of humerus fracture causes axillary nerve damage)

—> Axillary innervates deltoid and gives cutenous innervation to skin of deltoid and a small patch on upper lateral arm.

Question 4

After, axillary nerve, do Radial nerve!

Answer 4

For radial nerve–> remember!!—-> Radiating nurse extends from posterior hospital door, but mid-shift drops her crutches, and finds a screwdriver on tri-step supinator chair.

Radiating Nurse–> Radial Nerve
Posterior hospital door–> in posterior compartment of the arm, provides cutenous innervation to posterior skin of the arm. and door–>upper cutaneous innervation to dorsum of hand.

Crutches, Screwdriver, Saturday night palsy–> These can damage radial nerve—–> Axillary compression and Mid-shift–> mid-shaft fractures damage radial nerve!
Screwdriver–>Repetitive pronation/supination of forearm can damage radial nerve.
supples cuteneous innervation to dorsum of hand.

DROPS crutches—> wrist drop when radial nerve is damaged. wrist drop ki waja sey decreased grip strength of hands too.

Radial Nerve if damaged at axilla—> pt will come with flexed elbow!!!! (Because extension impaireddd)

screwdriver on tri-step supinator chair–> repetitive supination/pronation or dislocation of radial head will damage the supinator, and the supinator is where the deep branch of radial nerve enters to supply the muscles of finger and thumb extension, AND NORMAL TRICEP reflex–> For people, whose nerve is damage at this point or due to screwdriver–> sensation and triceps reflex will be normal, there will be just finger and thumb drop.

Question 5

After axillary, radial.

Now do Ulnar Nerve.

Answer 5

For ulnar nerve–> Remember little ullu claws using epic mediocre hammer that deviates to opposite intermittently.

Little–> remember that ulnar side is the side of the little finger/Also called medial most finger.
Ullu–> ulnar nerve
epic Mediocre hammar–> Ulnar nerve can be damage at medial epicondyle, and hook of hamate fracture!
Deviates to opposite side–> Radial deviation of wrist upon flexion (proximal lesion)
intermittently—-> Palmar and dorsal INTROSSEI are innervated by ulnar nerve (Asked in NBME20)–> It said, that the person cannot keep paper between fingers (Froment test)–> introssei are responsible for abduction and adduction.
Supplies Lumbricals of 4,5th digit–> responsible to make L’s of these fingers—so claw hand seen on extention.

Question 6

Now do Median Nerve.

Answer 6

With a the ape’s and pope’s blessing–> Lunatic Superhero is asked to flex his powers, go through the tunnel and face the opponent police in front of all the calling media.
Media–> Median Nerve
Flex his powers–> innervates flexors!
Lunatic superhero to go through tunnel–> Median nerve can be damaged proximally at superacondylar fracture of humerus (sirf iss lesion mein cutaneous sensation ka loss hota hai), it can be damaged in lunate bone fracture which causes carpal tunnel syndrome and also in colle’s fracture (calling media).

Opponent police—> innervates oppenens pollicis which is important for writing!–> lunate dislocation impairing median nerve also causes IMPAIRED THUMB ABDUCTION (asked in uworld)
Also supplies lumbricals of middle and index finger (L bnaatay hein lumbricals upon contraction)

CATCH–> Agar thenar emenance aur hand muscles affect ho rahay hein, per sensation intact hai hand ki—> Recurrent brand of Median Nerve is damaged.
(This happens when there is a superficial laceration in palm)

CATCH2–>median nerve injury can present as 2 sensory defect—>

1) only sensation of 3.5 digits lost–> compression at carpal tunnel.
2) Sensation is lost of lateral palm+ thenar eminence+ 3.5 digits–> Nerve is damaged between 2 heads of pronator teres/Flexor digitorum superficialis and flexor digitorum profundus.

Question 7

Wrist–> which two bones can affected/dislocated and what needs to be remembered?

Answer 7

Scaphoid–> most common for fracture, can be felt in the anatomical snuff box!–> Avascular necrosis.

Lunate bone–> causes carpal tunnel syndrome.
But in NBME20 they said, their is a bone fracture upon falling on outstretched hand. The anatomical snuff box in not tender. Which bone is affected?–> It was lunate!!!!!

Question 8

What makes guyon’s canal and what is its clinical significance?

Answer 8

Volar carpal ligament makes the roof, floor is by flexor carpal retinaculam, pisoform bone peechay and hamate thoraa agay.

Cycling can cause guyon’s canal syndrome, because this compressess the hook of hamate and that damages ulnar nerve.

Question 9

Erb’s and Klumpke’s palsy

Answer 9

Erb’s (C5-C6)–> Anterior trunk damaged while lateral force on the neck of the baby during delivery.
Waiter’s tip seen.
Arm is hung by side–> cannot abduct because deltoid affected.
Arm is medially rotates/internally rotated–> infraspinatus which causes external rotation.
Arm is extended and pronated–> biceps brachi is affected and that causes flexion and supination.

Klumpke’s pasly–> posterior trunk damaged (C8-T1) while force on arm during delivery/adults grabbing a tee branch—>TOTAL CLAW HAND.
(Lumbricals jab L nahyin bnaa saktay, woh uska opposite jo kay claw hai bnaa laetay hein)

Question 10

Winged scapula’s clinical significance and its root values?

Answer 10

Sarah has 5 wings of heaven
Sarah–> Serratus anterior affected.
Wing–> winged scapule can’t anchor scapule to thoracic cage.
heaven–> SEVEN–> C5-C7

occurs during mastectomy, axillary LN dissection

Question 11

In thoracic outlet syndrome, the signs/symptoms are due to compression of ___________.

Answer 11

lower trunk and subclavian vessels

Question 12

ACL and PCL come from which femur condyles?

Answer 12

Lateral femoral condyle to anterior tibia: ACL.
Medial femoral condyle to posterior tibia: PCL.
LAMP.

Question 13

In anterior and posterior drawer signs, there’s increased gliding of which bone?

Answer 13

Increased gliding of Tibia relative to femur!

Question 14

MCL injury occurs in?

Answer 14

Vulgar mother-fucking abs.

Increased Lateral/Valgas force–> tears MCL–> causes abnormal ABDUCTION

Question 15

McMurray Test

Answer 15

Popping sensation while external rotation–> medial meniscal tear (ME)

Popping sensation while internal rotation of knee–> Lateral meniscal tear

Question 16

Obturator nerve damage manifests as?

Answer 16

Obturator is MAD.

Decreased medial thigh sensation and
adduction.

Adductor of thigh that the obturator nerve supplies are: obturator externus, adductor longus, adductor
brevis, gracilis, pectineus, adductor magnus. (Every muscle name has a hint that it is an adductor or is supplied by obturator–> except for GRACILIS AND PECTINEUS–> can be asked!!)

Question 17

What lower extremity nerve can be damaged due to pregnancy? How will it manifest?

Answer 17

Lateral femoral cutaneous (L2-L3)—> Supplies anterior and lateral thigh sensation.

ASKED IN UWORLD.
Can be caused due to: tight clothing, obesity, pregnancy, pelvic procedures

Question 18

Which nerve can be damaged in pelvic fracture and how will the condition present?

Answer 18

Flormar at QIPS mall.—> Femoral nerve can be damaged.
AT–> anterior thigh sensation and Mall–> Medial leg sensation are lost.

decreased leg extention, decreased patellar reflex.
Motor—quadriceps, iliacus, pectineus, sartorius

Question 19

Which injury causes urinary incontinence after childbirth?

Answer 19

Pudendal nerve–> S2-S4

Can be damaged–> during childbirth and damage causes decreases perineal sensation (asked so many times for males), urinary and fecal incontinence.

Nerve block—> pudendal nerve can be blocked during childbirth as an anesthetic at ischial spine.

Question 20

Root Values of Obturator, femoral and Pudendal?

Answer 20

Obturator and femoral are same–> L2-L4

Pudendal is–> S2-S4

Question 21

Which muscle is important for elbow extension/triceps reflex and which muscle impairment causes wrist drop?

Answer 21

triceps brachii (responsible for elbow extension and triceps reflex) 
extensor carpi radialis longus (responsible for wrist extension)

Question 22

In ulnar nerve lesion, the patient is most likely to have weakness of which of the following movements?
(uworld)
A) Elbow extension
B) Shoulder abduction
C) Wrist abduction
D) Wrist adduction
E) Wrist extension

Answer 22

Wrist adduction-CORRECT.

The ulnar nerve impairment causes radial deviation of the hand upon flexion—-> and this basically means that the wrist can’t be ADDUCTED.

Question 23

Which muscles are affected in de-quervain tendinopathy?

Answer 23

Thickened tendon sheaths of:
(Police abducted them for long, but they extended bravely)
1) Abductor pollicis longus
2) extensor pollicis brevis

Pain upon writing/pain upon thumb stretching/thumb extension. (Not written in the book, so definitely could be tested)