MSK injuries Flashcards
(34 cards)
What are the shoulder muscles that form the rotator cuff?
-Supraspinatus, Infraspinatus, teres minor, Subscapularis
What muscles are innervated by the suprascapular nerve?
Supraspinatus and infraspinatus
What nerve innervates teres minor?
Axillary nerve
What innervates the subscapularis?
Upper and lower subscapular nerves
What is the most common fracture of the carpal bones? and how?
Scaphoid; due to a fall on an outstretched hand-> avascular necrosis
What can cause acute carpal tunnel syndrome?
Dislocation of the lunate
How are you gonna remember all the wrist bones?
So Long To Pinky, Here Comes The Thumb
Scaphoid, Lunate, Triquetium, Pisiform, Hamate, Capitate, Trapezoid, Trapezium
What is Carpal Tunnel Syndrome associated with?
-Pregnancy, Rheumatoid Arthritis, Hypothyroidism, Diabetes, Dialysis-related amyloidosis; repetitive use
What is Guyon Canal Syndrome?
- Compression of ulnar nerve @ wrist or hand -> in the guyon canal aka Ulnar tunnel syndrome
- Pressure from handlebars
Axillary nerve injury would be caused by? Presentation?
-Fractured surgical neck of humerus; anterior dislocation of humerus
Presentation: Flattened deltoid, loss of arm abduction at shoulder (>15 degrees), Loss of sensation over deltoid muscle and lateral arm
C5-6
Musculocutaneous nerve injury?
(C5-7) -Caused: upper trunk compression Presentation: -Loss of forearm flexion and supination -Loss of sensation over lateral forearm
Radial nerve injury?
Caused: Midshaft fracture of humerus; Compression of axilla; ex: due to crutches or sleeping with arm over chair (“Saturday Night Palsy”)
Presentation: Wrist drop, loss of elbow, wrist and finger extension
-Weakness/ decrease in grip strength (wrist extension necessary for maximal action of flexors)
What are the major flexors of the wrist?
Flexor carpi radialis and flexor carpi ulnaris
-Median and Ulnar nerves
What are the major extensors of the wrist?
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor carpi ulnaris
-Radial nerve
Median nerve injury?
Caused: Supracondylar fracture of humerus (proximal lesion)
- Carpal tunnel syndrome and wrist laceration (distal)
- Ape hand/pope blessing
- loss of wrist flexion, flexion of lateral fingers, thumb opposition, lumbricals of 2nd and 3rd digits
- Loss of sensation over thenar eminence and dorsal and palmar aspects of lateral 3 1/2 fingers with proximal lesion
Ulnar nerve injury?
- Fracture of medial epicondyle of humerus “funny bone” (proximal lesion)
- Fractured hook of hamate (distal lesion)
Presentation: Loss of wrist flexion, flexion of medial fingers, abduction and adduction of fingers (interossei), actions of medial 2 lumbrical muscles
Sensation loss: over medial 1 2/2 fingers including hypothenar eminence
Injury to Recurrent branch of median nerve (C5-T1) ?
- Superficial laceration of palm
- “Ape of hand”
- loss of thenar muscle group: opposition, abduction, and flexion of thumb
- no loss of sensation
What do the lumbricals do?
-Flex at the MCP and flex at the DIP and PIP
Cause and presentation of Obturator nerve?
(L2-L4)
Cause: Pelvic surgery
Presentation: decrease sensation in the medial thigh and decreased adduction because it innervates the adductor longus, adductor brevis, and gracilis muscles
Cause and presentation of Femoral nerve?
(L2-L4)
Cause: Pelvic Fracture
Presentation: Decrease in thigh flexion and leg extension
-innervates the anterior thigh muscles that flex the hip joint and extend the knee
Cause and presentation of Common Peroneal nerve?
-(L4-S2)
Caused: Trauma or compression of lateral aspect of leg, fibular neck fracture
Presentation: Foot drop- inverted and plantarflexed at rest, loss of eversion, and dorsiflexion
“Steppage gait”
-LOSS OF SENSATION ON DORSUM OF FOOT
PED= Peroneal Everts and Dorsiflexes; if injured, foot dropPED
Cause and presentation Tibial nerve?
(L4-S3)
- Knee trauma, Baker cyst (proximal lesion)
- Tarsal Tunnel Syndrome (Distal lesion)
- Inability to curl toes and loss of sensation on sole of foot
- Proximal lesions, foot everted at rest with loss of inversion and plantarflexion
TIP= Tibial Inverts and Plantarflexes; If injured, can’t stand on TIPtoes
Cause of Superior gluteal nerve injury?
-Iatrogenic injury during intramuscular injection to upper medial gluteal region
Presentation of Superior gluteal nerve injury?
- Trendelenburg sign/gait-pelvis tilts because weight-bearing leg cannot maintain alignment of pelvis through hip abduction.
- Lesion is contralateral to the side of the hip that drops, ipsilateral to extremity on which the patient stands
