Musculoskeletal System Flashcards
(231 cards)
1
Q
What is another name for fossa?
A
Cavity
2
Q
What is another name for sulcus?
A
Groove
3
Q
When is a depression called a sulcus/groove and not a fossa?
A
When a blood vessel/tendon/structure is running through it.
4
Q
What is a notch?
A
U shaped structure
5
Q
What are the true joints in the shoulder?
A
Sternoclavicular joint Acromioclavicular joint Glenohumeral joint (shoulder joint)
6
Q
Where does the deltoid attach on the humerous?
A
Deltoid tuberosity
7
Q
What is the function of rotator cuff muscles?
A
They stabilise glenohumeral joint (shoulder joint)
8
Q
What are the rotator cuff muscles?
A
Supraspinatus
Infraspinatus
Teres Minor
Subscapularis
9
Q
Where does the brachial artery end?
A
Elbow joint
10
Q
Where does the axillary artery end?
A
Below teres major
11
Q
What is the shoulder girdle?
A
Scapula
Clavicle
12
Q
What is the name of the concave depression on the costal side of the scapula?
A
Subscapular fossa
13
Q
To which part of the scapula does the short head of biceps brachii attach?
A
Coracoid process
14
Q
Which fossa of the scapula articulates with the humerus?
A
Glenoid fossa
15
Q
What part of the scapula articulates with the clavicle?
A
Acromion
16
Q
Injury to which nerve causes winging of the scapula and which muscle does this innervate?
A
Long thoracic nerve which innervates the serratus anterior muscle
17
Q
What are the functions of the clavicle?
A
Attaches upper limb to trunk
Protects underlying neurovascular structures
Transmits force from the upper limb to the axial skeleton
18
Q
What attaches to the clavicle at the considered tubercle?
A
Conoid ligament (medial part of the coracoclavicular ligament)
19
Q
What is the most common point of fracture of the clavicle?
A
Between medial 2/3 and lateral 1/3 as this is the weakest point- structure of clavicle changes
20
Q
Which nerve can be damaged in a clavicular fracture?
A
Suprascapular nerves- damaged by upwards movement of medial fragment
21
Q
What is a tubercle?
A
A round nodule on a bone and signifies an attachment site of a muscle or ligament
22
Q
What is a facet?
A
Small smooth area on a bone covered with articular cartilage
23
Q
Which of the rotator cuff muscles does not attach to the greater tubercle of the humerus?
A
Subscapularis- attaches to the lesser tubercle of the humerus anteriorly
24
Q
Which nerve can be damaged in a surgical neck fracture of the humerus?
A
Axillary nerve- very close to the surgical neck
25
What deformity occurs if there is damage to the radial nerve?
Wrist drop
| radial nerve innervates the extensors of the wrist so damage results in unopposed flexion of the wrist
26
Which bone does the trochlea of the humerus articulate with?
Ulna
27
Which fossae are located on the distal humerus?
Radial fossa- anterior humerus
Coronoid fossa- anterior humerus
Olecranon fossa- posterior humerus
28
Which fracture of the humerus can lead to Volkmanns contracture?
Supraepicondylar fracture- transverse fracture spanning between the two epicondyles
Results in interference to the blood supply of the forearm from the brachial artery.
Ischaemia results in uncontrolled flexion of the hand because muscles become fibrotic and short.
29
What area on the ulna articulates with the head of the radius?
Radial notch
30
Which muscle attaches to the tuberosity of the ulna?
Brachialis
31
Which muscle attaches to the anterior shaft of the ulna?
Pronator quadratus
32
Where is the most likely point of fracture on the ulna?
Shaft
33
Which bones does the radius articulate with?
Ulna
Humerus
Scaphoid
Lunate
34
Which muscle attaches to the lateral surface of the radius?
Pronator teres
35
Which landmark on the radius articulates with the distal ulna?
Ulnar notch
36
In a Colles fracture, in which direction is the distal radius displaced?
Posterior
37
What is a sesamoid bone?
A small independent bone or bony nodule developed in a tendon where it passes over an angular structure
38
Where will pain be felt in a scaphoid fracture?
Anatomical snuffbox
39
Which nerve can be damaged in a fracture of the lunate?
Median nerve
40
Which metacarpal is fractured in a Boxers fracture?
Fifth - fracture of this bone often occurs as a result of a clenched fist striking a hard surface in a hammer punch
41
Which digit only contains two phalanges, as opposed to three?
Thumb
42
What is the innervation of pectoralis major?
Medial and lateral pectoral nerves
43
What action does the clavicular head of pectoralis major perform on the shoulder?
Flexion
| Also helped by some anterior fibres of the deltoid muscle
44
Where is pectoralis minor located in comparison to pectoralis major?
Posterior
45
Where on the scapula does pectoralis minor attach?
Corocoid process
46
Which wall of the axilla does serratus anterior form?
Medial- serratus anterior is found on the outer aspect of the rib cage
47
What is the main action of serratus anterior?
Rotating the scapula- allows the arm to be raised over 90 degrees
48
Injury to which nerve can cause winging of the scapula?
Long thoracic nerve- supplies serratus anterior which holds the scapula against the rib cage
49
What is the quadrangular space?
Gap that the axillary nerve and posterior circumflex humeral artery pass through to reach the posterior scapula region
50
Which nerve innervates the deltoid muscles?
Axillary nerve
51
What is the action of the anterior fibres of the deltoid?
Flexes the shoulder
52
Which nerve innervates teres major?
Lower subscapular nerve
53
What are the actions of teres major?
Medial rotation of the arm
| Adduction of shoulder
54
Which nerve innervates supraspinatus?
Suprascapular nerve
55
What is the action of infraspinatus?
Lateral rotation of the arm
56
Which nerve innervates teres minor?
Axillary nerve
57
Which muscle is typically affected in rotator cuff tendinitis?
Supraspinatus
58
What forms the medial wall of the axilla?
Serratus anterior and thoracic wall
59
The subscapularis muscle forms which border of the axilla?
Posterior wall
60
What structure enters the axilla through the clavipectoral triangle?
Cephalic vein
61
Which muscles travel through the axilla?
Short head of biceps brachii
| Coracobrachialis
62
What can be biopsied in suspected breast cancer?
Axillary lymph nodes as these are the nodes to which 75% of lymph fluid from the breast drains first.
63
Which nerve innervates the trapezius muscle?
Accessory nerve
64
What is the action of the middle fibres of the trapezius?
Retract the scapula
65
Which nerve innervates latissimus dorsi?
Thoracodorsal nerve
66
What is the action of levator scapulae?
Elevates the scapula
67
Which nerve innervates the rhomboids?
Dorsal scapular nerve
68
What is the action of the rhomboid?
Retract and rotate the scapula
69
Which nerve innervates the anterior compartment of the upper arm?
Musculocutaneous nerve
70
Where does the long head of the biceps brachial originate?
Supraglenoid tubercle
71
What is the main function of biceps brachii?
Supination of the forearm
72
What is the action of coracobrachialis?
Flex and adduct arm
73
What is the action of triceps brachii?
Extension of the elbow
74
Where do the superficial muscles of the anterior forearm originate?
Medial epicondyle of the humerus
75
Which nerve innervates flexor carpi ulnaris?
Ulnar nerve
All muscles in anterior forearm are innervated by median nerve except:
Flexor carpi ulnaris
Medial half of flexor digitorum profundus (innervates ring finger and little finger)
76
Which nerve innervates flexor carpi radialis?
Median nerve
77
What is the action of pronator teres?
Pronation of the forearm
78
Which of the following joints does flexor digitorum superficialis not act on?
- wrist
- metacarpophalangeal joints
- distal interphalangeal joints
- proximal interphalangeal joints
Distal interphalangeal joints - only acted on by flexor digitorum profundus
79
Which nerve innervates the lateral half of flexor digitorum profundus and which fingers does this innervate?
Median nerve- middle finger and index finger
80
Where does flexor pollicis longus lie in relation to flexor digitorum profundus?
Lateral
81
What is the action of pronator quadratus?
Pronation of the forearm
82
What is the action of the brachioradialis?
Flexion of the elbow
83
What nerve innervates all the muscles in the posterior forearm?
Radial nerve
84
What is the main action of extensor digiti minimi?
Extension of the little finger
85
What is the action of anconeus?
Abducts the ulna in pronation
| Extends at elbow joint
86
What is the common site of origin for posterior forearm muscles?
Lateral epicondyle
87
Which muscle tendons contribute to the borders of the anatomical snuffbox?
Abductor pollicis longus = lateral border
Extensor pollicis brevis = lateral border
Extensor pollicis longus = medial border
88
Which border of the anatomical snuffbox does the tendon of extensor pollicis longus form?
Medial
89
Which joint does extensor pollicis brevity act on?
Metacarpophalangeal joints of the thumb
| Carpometacarpal joints of the thumb
90
Injury to which nerve results in wrist drop?
Radial nerve
91
Where are the common sites of injury that result in wrist drop and how?
Axilla - injured via humeral dislocations or fractures of proximal humerus
Radial groove of humerus- injured via humeral shaft fracture
DAMAGES RADIAL NERVE
92
What is the action of opponens pollicis?
Opposition of the thumb
93
Which nerve innervates flexor pollicis brevis?
Median nerve innervates the thenar eminence
94
Which nerve innervates opponents digiti minimi?
Ulnar nerve innervates the hypothenar eminence
95
What is the action of abductor digiti minimise?
Abduction of the little finger
96
Which nerve innervates the medial two lumbricals?
Ulnar nerve
97
What action does the lumbricals have on the metacarpophalangeal joints?
Flexion
98
What is the action of the dorsal interossei?
Abduction of the fingers
99
What is the action of palmaris brevis?
Deeps the curvature of the hand to improve grip
100
What are the extrinsic muscles of the hand?
Muscles in the anterior and posterior compartments of the forearm that control crude movements and produce a forceful grip
101
What are the ligaments of the shoulder joint? (4)
Glenohumeral ligaments x3
Transverse humeral ligament
Coracohumeral ligament
Coracoacromial ligament
102
Which artery supplies the shoulder joint?
Suprascapular artery
103
Which nerves supply innervation to the shoulder joint?
Axillary nerves
Suprascapular nerve
Lateral pectoral nerve
104
What contributes to the stability of the shoulder joint?
Ligaments
Glenoid labrum
Rotator cuff muscles
105
What is the most common direction of dislocation of the shoulder joint?
Anterior
106
What are the articulating surfaces of the elbow joint?
Trochlear notch of the ulna and the trochlear of the humerus
Head of the radius and the capitulum of the humerus
107
Which muscles contribute to flexion of the elbow joint?
Brachialis
Biceps brachii
Brachioradialis
108
What are the clinically important bursae of the elbow joint?
Intratendinous - located within the tendon of the triceps brachii
Subtendinous - between the olecranon and the tendon of the triceps brachii, reducing friction between the two structures during flexion and extension of the arm
Subcutaneous- between the olecranon and overlying connective tissue
109
What area becomes inflamed in tennis elbow?
Lateral epicondyle- main site of attachment of extensor tendons
Caused by overuse strain on tendons
110
What nerves are at risk of damage in a supraepicondyle fracture?
Medial, ulnar or radial nerves
111
Which bones form the articulatory surfaces of the wrist joint?
Distal end of the radius and articular disk
| Proximal row of the carpal bones- scaphoid, lunate, triquetrum (except pisiform)
112
Which type of joint is the wrist?
Ellipsoid synovial joint = allows movement along two axis ie. flexion/extension AND abduction/adduction
113
Which bone in the hand when fractured is most likely to result in avascular necrosis and why?
Scaphoid- the bone has distal to proximal blood supply and this may be disrupted
114
Which nerves provide innervation to the wrist joint?
Median nerve
Radial nerve
Ulnar nerve
115
Which artery accompanies the axillary nerve when exiting the axilla in the quadrangular space?
Posterior humeral circumflex artery
116
What forms the inferior border of the quadrangular space?
Teres major
117
Which muscles does the axillary nerve innervate?
Deltoid
| Teres minor
118
What area does the axillary nerve provide sensory innervation to?
Regimental badge area
119
Which muscle rapidly atrophies following damage to the axillary nerve?
Deltoid
120
Which nerve roots contribute to the musculocutaneous nerve?
C5 C6 C7
121
Which cord of the brachial plexus gives rise to the musculocutaneous nerve?
Lateral
122
What is the name of the sensory branch of the musculocutaneous nerve?
Lateral cutaneous branch- provides sensory innervation to the skin of the lateral forearm
123
Which muscles does the muscle does the musculocutaneous nerve innervate?
Biceps brachii
Brachialis
Coracobrachialis
124
Which area does the musculocutaneous nerve provide sensory innervation to?
Lateral forearm
125
The median nerve innervates all muscles in the anterior forearm except...
Flexor carpi ulnaris - ulnar nerve
| Medial half of flexor digitorum profundus - ulnar nerve
126
The ulnar nerve provides motor innervation to all muscles in the hand except...
Thenar muscles - median nerve
| Lateral two lumbricals (middle and index finger) - median nerve
127
Which nerve roots contribute to the median nerve?
C6 C7 C8 T1
128
Which artery does the median nerve cross in the arm?
Brachial artery
129
Which group of muscles atrophied in carpal tunnel syndrome?
Thenar eminence
130
Which deformity occurs when the median nerve is damaged at the elbow?
Hand of Benediction
131
Which landmark of the humerus marks the course of the radial nerve?
Radial groove- small depression on the posterior aspect of the humerus
132
Which group of muscles does the radial nerve innervate?
Posterior arm
133
How many cutaneous branches does the radial nerve give off?
Four
134
What deformity occurs if there is damage to the radial nerve in the axilla?
Wrist drop
135
Which muscles are affected if the superficial branch of the radial nerve is damaged?
None- this is a sensory nerve
136
At what bony landmark of the humerus is the ulnar nerve vulnerable to damage?
Medial epicondyle
137
Which muscle does the ulnar nerve pierce in the forearm?
Flexor carpi ulnaris-passes between the two heads
138
Which fingers does the ulnar nerve provide cutaneous innervation to?
Medial one and a half fingers
139
What deformity occurs if the ulnar nerve is injured at the wrist?
Ulnar claw
140
Which vessel does the left subclavian artery arise from?
Arch of the aorta
141
What muscle does the axillary artery pass beneath?
Pectoralis minor
142
What is the name of the deep artery of the arm?
Profunda brachii
143
What clinical sign indicates ischaemia of the forearm?
Volkmann's contracture- scar tissue results in muscle shortening
144
Which arteries directly supplies blood to the hand?
Superficial and deep palmar arches
145
What is the superficial palmar arch found deep to?
Palmar aponeurosis
146
At what point does the basilica vein move deep in the arm?
Border of teres major
147
Which vein does the cephalic vein drain into?
Axillary vein
148
What are the deep veins of the arm situated beneath?
Deep fascia
149
What name is given to the arrangement of accompanying veins around an artery?
Vena comitantes
150
What are the superficial veins in the upper limb
Basilic vein
Cephalic vein
Both drain into axillary vein
151
What forms the medial border of the cubital fossa?
Lateral border of pronator teres
152
What forms the floor of the cubical fossa?
Brachialis and supinator
153
Name the structures in the cubical fossa, lateral to medial.
Radial nerve
Biceps tendon
Brachial artery
Median nerve
154
Where can you feel the for the brachial pulse?
Medial to the biceps tendon
155
What vein is commonly used for venepuncture?
Median cubical vein - superficial and easily accessible
156
What forms the medial border of the anatomical snuffbox?
Tendon of extensor pollicis longus
157
What bones form part of the floor of the anatomical snuffbox?
Scaphoid and trapezium
158
Which artery passes through the anatomical snuffbox?
Radial artery
159
Which vein passes through the anatomical snuffbox?
Cephalic vein
160
What causes tenderness in the anatomical snuffbox?
Scaphoid fracture- vulnerable to avascular necrosis as blood flow is lateral to medial
161
On which side of the leg is the fibula found?
Lateral aspect
162
Which key nerve of the leg wraps around the neck of the fibula?
Common fibula- after wrapping around the neck of the fibula, the common fibula nerve gives rise to the superficial and deep fibula nerves
163
Which movement of the ankle can lead to a spiral fracture of the fibula?
Lateral rotation - the force of the talus against the lateral malleolus of the fibula causes a spiral fracture
164
What is the name of the flat surface at the superior end of the tibia, formed by the condyles?
Tibial plateau
165
Which structure articulates with the intercondylar fossa of the femur?
Intercondylar eminence of the tibia - combination of intercondylar tubercles and area of roughened bone between them
166
Which structure of the anterior tibia is damaged to cause bruising?
Tibial tuberosity- marks the anterior surface of the tibia where the periosteal covering is particularly open to damage
167
Which two bony structures are implicated in a spiral fracture of the tibia and how?
Medial malleolus and talus- over inversion of the ankle joint, the talus is forced into the medial malleolus causing a spiral fracture
168
What type of bone is the patella?
Sesamoid
169
What attaches to the base of the patella?
Quadriceps tendon - provides attachment of the quadriceps (3 vastus muscles and rectus femoris)
170
What attaches to the apex of the patella?
Patellar ligament- connects the patella to the tibial tuberosity
171
In what direction is the patella most likely to dislocate?
Laterally- the medial collateral ligament is weaker than the lateral collateral ligament making it more susceptible to injury and lateral patellar dislocation more likely
172
To which part of the femur do the lateral rotators of the lower limb attach to?
Greater trochanter- this is the lateral aspect of the hip joint so the lateral rotators attach here
173
Which strong ligament attaches to the intertrochanteric line?
Iliofemoral ligament
174
On which part of the femur can you find the intertrochanteric crest?
Posterior aspect
175
What happens to the position of the lower limb after neck of femur fracture?
Laterally rotated and superiorly displaced (shortened)
176
What is the name of the structure to which adductor magnus attaches?
Adductor tubercle
177
Which two structures at the distal end of the femur articulate with the tibia to create the knee joint?
Condyles
178
How many bones make up the tarsals?
Seven:
| Calcaneus, navicular, talus, cuboid, three cuneiforms
179
Which bones articulate with the talus?
Tibia and Fibula (ankle joint)
Calcaneus
Navicular
180
To which bone of the foot does tibialis posterior inset into?
Tibialis posterior inserts into the navicular after passing through the tarsal tunnel to produce inversion
181
Which is the most lateral bone in the distal row of the tarsals?
Cuboid
182
Why do fractures of the talus have minimal displacement?
The talus is found firmly supported within the malleoli and this prevents them from displacing
183
A strain of which muscle can lead to an allusion fracture of the 5th metatarsal?
Fibularis brevis- attaches to 5th metatarsal and can cause avulsion fractures especially in forced inversion
184
What is the insertion of the gluteus maximum?
Gluteus tuberosity- lateral ridge of the linea aspera
185
Which nerve innervates the gluteus maximum?
Inferior gluteal
186
Damage to which nerve causes a pelvic drop?
Superior gluteal
Loss of gluteus medium and minimus activation
These muscles contract when the contralateral leg is raised, preventing the pelvis from dropping on that side
187
Which muscle lies between the gemilli?
Obturator internis
188
Which muscle of the quadriceps crosses both the hip and knee joint?
Rectus femoris - flexes hip joint, extends knee joint
189
What is the innervation of psoas major?
Anterior rami L1-L3
190
Describe the function of sartorius at the hip.
Flexion, abduction, lateral rotation
191
Damage to which nerve root would affect the function of the femoral nerve?
L3
192
From which nerve plexus does the obturator nerve arise?
Lumbar plexus
193
Which two nerves innervate adductor magnus?
Tibial nerve supplies hamstring part
| Obturator nerve supplies adductor part
194
Which muscle is the most superior muscle of the medial thigh?
Obturator externus
195
What are the hamstrings?
Muscles in the posterior compartment of the thigh:
Biceps femoris
Semitendinous
Semimembranosus
They extend at the hip and flex at the knee
196
What innervates the short head of biceps femoris?
Common fibular part of sciatic nerve
197
Which is the most medial muscle of the hamstrings?
Semimembranosus
198
What is the correct function of all the hamstrings at the knee?
Flexion- they attach to the posterior aspect and reduce the angle found at the joint
199
Which muscle of the hamstrings causes lateral rotation at the hip and knee?
Biceps femoris - located on the lateral aspect of the knee joint
200
Which of the four muscles in the anterior compartment of the leg cause eversion at the ankle?
Fibularis tertius
201
What are the nerve roots of the deep fibula nerve?
L4-L5
202
Which muscle attaches to the base of the first metatarsal?
Tibialis anterior
203
What causes a foot drop?
Damage to the common fibula nerve causing loss of dorsiflexion
204
Which is the most superficial of the muscles of the anterior leg?
Tibialis anterior
205
In which direction does the sole of the foot turn to face during eversion?
Laterally
206
Which nerve innervates both muscles of the lateral leg?
Superficial fibular nerve
207
What is a function of fibularis longus that is not shared by fibularis brevity?
Plantarflexion
208
Which nerve roots does the calcaneal reflex assess?
S1-S2
209
Which muscle flexes at the knee and plantarflex at the ankle?
Gastrocnemius
210
Which movement places the calcaneal tendon most at risk?
Forceful jumping
211
In which direction does the femur move to unlock the knee?
Rotates laterally
212
What is the function of tibialis posterior?
Plantar flexion and inversion
213
Which muscle passes closest to the medial malleolus from the deep muscles of the leg?
Tibialis posterior
214
How can you tell whether you are looking at the left or right humerus?
Medial epicondyle is larger and projects further than the lateral epicondyle
215
Which is the biggest carpal bone?
Capitate
216
How does the axillary artery exit the axilla?
| What structure also goes through here?
Quadrangular space
Posterior humeral circumflex artery
217
What are the boundaries of the quadrangular space?
Superior
Subscapularis and teres minor
Inferior
Teres major
Lateral
Surgical neck of humerus
Medial
Long head of triceps brachii
218
What goes through the quadrangular space?
Axillary artery
| Posterior humeral circumflex artery
219
Describe the anatomical course of the axillary nerve.
-formed within the axilla region from the posterior cord of the brachial plexus, posterior to the clavicle
-lies posteriorly to the axillary artery and anteriorly to the subscapularis muscle
-descends to the inferior border of the subscapularis muscle
-exits the axilla via the quadrangular space, with the posterior humeral circumflex artery
-terminates by dividing into 2 branches:
Posterior terminal branch - motor innervation teres minor and sensory innervation to skin over the inferior part of the deltoid (regimental badge area)
Anterior terminal branch - motor innervation to deltoid
220
What would injury to the axillary nerve present as?
Motor functions: paralysis of deltoid and teres minor muscles. Loss of abduction
Sensory functions: posterior terminal branch gives cutaneous innervation to the skin over the lower deltoid (regimental badge area)
Characteristic clinical signs:
Paralysed deltoid muscle rapidly atrophies, greater tuberosity can be palpated
221
Describe the anatomical course of the radial nerve.
Arises in axilla region from the posterior cord
Exits via the triangular interval to the posterior arm with profunda brachii
Descends down the humerus in the radial groove with profound a brachii
Moves anteriorly over the lateral epicondyle through the cubical fossa to enter the forearm
Branches into 2:
-deep branch (motor) - innervates most of the muscles in the posterior compartment of the forearm
-superficial branch (sensory) - contributes to the cutaneous innervation of the hand and fingers
222
What does the profunda brachii supply?
Supplies the posterior compartment of the upper arm
223
The trapezius attaches to the acromion, spine of the scapula and lateral clavicle.
Another muscle originates in the same places, which muscle?
Deltoid
224
All muscles in the anterior forearm are innervated by the median nerve except...
Extensor carpi ulnaris
Medial half of flexor digitorum profundus
Are innervated by the ulnar nerve
225
All muscles in the hand are innervated by the ulnar nerve except...
Thenar muscles
Lateral two lumbricals
Are innervated by the median nerve
226
Describe the anatomical course of the median nerve.
Derived from the medial and lateral cords of the brachial plexus in the axilla
Descends down the arm, initially lateral to the brachial artery
Halfway down the arm, the nerve crosses over the brachial artery and is edible to it
Enters the anterior compartment of the forearm via the cubical fossa
Travels between flexor digitorum profundus and flexor digitorum superficialis
Enters hand via the carpal tunnel and terminates by dividing into:
-recurrent branch - supplies thenar muscles
-palmar digital branch - supplies fingertips of lateral 3 and a half digits and lateral 2 lumbricals
227
Sensory innervation of dorsal lateral 3 and a half digits and associated palm area is by...
Radial nerve
228
Sensory innervation to the fingertips of the lateral 3 and a half digits is by...
Median nerve
229
What is the sensory function of the median nerve in the hand?
Palmar cutaneous branch - palm area of lateral 3 and a half digits
Palmar digital cutaneous branch - anterior lateral 3 digits and fingertips
230
Describe the anatomical course of the ulnar nerve.
Derived from the medial cord of the brachial plexus in the axilla
Descends down the medial side of the upper arm
At the elbow, passes posterior to the medial epicondyle entering the forearm
In the forearm, pierces the two heads of flexor carpi ulnaris and travels alongside the ulnar
Three branches arise:
-muscular branch - medial half of flexor digitorum profundus
-palmar cutaneous branch - medial palm
-dorsal cutaneous branch - anterior and dorsal 1 and a half digits and associated dorsal palm area
231
Describe the anatomical course of the musculocutaneous nerve.
Arises from the lateral cord of the brachial plexus
Leaves the axilla and pierces the coracobrachialis muscle near its point of insertion on the humerus (level of deltoid tuberosity)
Passes down the arm, anterior to the brachialis muscle but deep to biceps brachii
Emerges laterally to the biceps tendon and continues into the forearm as the lateral cutaneous nerve.
