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Flashcards in MSK Deck (79)
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Valgus/varus stress test

Valgus tests MCL (push laterally)
Varus tests LFL (push medially)


McMurray test

Popping on external rotation: medial meniscus tear
Popping on internal rotation: lateral meniscus tear


Unhappy triad

Occurs due to lateral force applied to planted leg. Classicaly damages ACL, MCL, and medial meniscus


Prepatellar bursitis

Repeted trauma or pressure from extensive kneeling


Baker cyst

Popliteal fluid related to chronic joint disease


Muscles of the rotator cuff

Supraspinatus: abducts arm initially, assessed by empty can test; suprascapular nerve

Infraspinatus: laterall forates the arm; suprascapular nerve

Teres minor: adducts and laterally rotates arm; axillary nerve

Subscapularis: medially roates and adducts; upper and low subscapular nerve


Golfer's elbow

Medial epicondylitis. Repetitive flexion


Tennis elbo

Lateral epicondylitis. Repetic extension


Bones of wrist

Scared lovers try positions that they can't handle



Fractures of wrist

Scaphoid most commonly fractured. Palpated in anatomic snuff box. Prone to avascular necrosis.

Hook of hamate fractured on fall on an outstretched hand. Can cause ulnar nerve injury


Axillary nerve damage

Occurs due to fractured surgical neck of humerus. Presents with loss of arm abductaion and loss of sensation over deltoid and lateral arm


Musculocutaneous nerve damage

Occurs due to upper trunk compreesion. Presents with loss of forearm flexion and supination, loss of sensation over lateral forearm


Radial nerve damage

Occurs due to midshaft fracture of humerus or compression of axilla. Presents with wrist drop, decreased grip strength, loss of sensation over posterior arm/forearm and dorsal hand


Median nerve damage

Occurs due to supracondylar fracture of humerus, carpal tunnel syndrome, wrist laceration. Presents with loss of wrist and lateral finger flexion, loss of opposition of thumb, inability to pronate. Loss of sensation over thenar eminence, lateral 3.5 fingers


Ulnar nerve damage

Occurs due to fracture of the medial epicondyle, fractured hook of hamate. Presents with ulnar claw, radial deviation of wrist, loss of wrist flexion and flexion of medial fingers, loss of ab and adduction of fingers, loss of sensation over medial fingers and hypothenar eminence


Recurrent branch of median nerve damage

Occurs due to superficial laceration of palm. Loss of thenar muscles - opposition, abduction, flexion of thumb. No loss of sensation.


Upper trunk of brachial plexus

Derived from C5, C6. Damaged in Erb palsy (waiter's tip). Seen in infants due to lateral traction on neck during delivery. Deficits in axillary nerve (deltoid), suprascapular nerve (supraspinatus and infraspinatus) and musculocutanous nerve (biceps)


Lower trunk of brachial plexus

Derived from C8, T1. Damaged in Klumpke palsy. Seen in infants due to upward force on arm during delivery. Deficits in median and ulnar nerves resulting in total claw hand


Long thoracic nerve

Derived from C5 through C7. Presents with winged scapula due to loss of function in serratus anterior. Damaged with axillary node dissection after mastectomy and stab wounds.


Thoracic outlet syndrome

Seen in pancoast tumor. Causes compression of lower trunk and subclavian vessels. Presents with atrophy of intrinsic hand muscles and total claw hand plus with ischemia, pain, edema


Presentation of proximal and distal medial and ulnar nerve damage

Distal ulnar: can't extend third and fourth fingers; remain clawed at rest or when extending fingers
Proximal ulnar nerve: ok gesture when trying to make a fist - can't flex fourth and fifith fingers

Distal median nerve: cant extend first and second fingers at rest
Proximal median nerve: can't flex first and second fingers when making a fist


Functions of dorsal and palmar interossei

DAB and PAD: dorsals abduct, palmars adduct


Obturator nerve

L2-L4. Damaged in pelvic surgery. Presents with decreased medial thigh sensation and decreased adduction


Femoral nerve

L2-L4. Damaged in pelvic fracture. Presents with decreased thigh flexion and leg extension.


Common peroneal nerve

L4-S2. Damaged with trauma to lateral leg, fibular neck fracture. Presents with foot drop - inverted and plantarflexed foot at rest. Loss of sensation on dorsum of foot


Tibial nerve

L4-S3. Damaged in knee trauma, Baker cyst, tarsal tunnel syndrome. Presents with inability to curl toes, everted foot, loss of sensation on sole of foot


Superior gluteal nerve

L4-S1. Damaged during IM infection to upper medial gluteus. Innervates gluteus minimus and medius. Presents with trendelenburg sign 0 pelvis tilts to side contralaterla to lesion


Inferior gluteal nerve

L5-S2. Damaged due to posterior hip dislocation. Innervates gluteus maximus. Presents with trouble clmbing stairs and standing up. Loss of hip extension.


Peroneal vs tibial nverve

Peroneal everts and dorsiflex
Tibial inverts and plantarflexes


Sciatic nerve

L4-S3. Innervates posterior thigh