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MSK Answers
1) For each of the following muscles, state their action & innervation
 Biceps femoris – extends hip & flexes knee, tibial & common fibular nerves L5-S2
 Brachioradialis – flexes forearm at elbow, radial nerve C5-C7
 Coracobrachialis – flexion & adduction of arm, musculocutaneous C6-C7
 Gluteus medius – abducts thigh & rotates hip in all directions, superior gluteal nerve
 Gracilis – flexes knee & adducts thigh, obturator nerve L2-L4
 Iliacus – flexes thigh, femoral nerve L2-L4
 Infraspinatus – laterally rotates arm & stabilises shoulder, suprascapular nerve C5-C6
 Palmar interossei – ulnar nerve, C8-T1
 Pectoralis major – flexes, medially rotates & adducts humerus, lateral & medial pectoral nerves,
C5-T1
 Sartorius – flexes & laterally rotates hip & flexes knee, femoral nerve, L2-L4
2) State the borders of the femoral triangle
Superior = inguinal ligament
Lateral = Sartorius
Medial = adductor longus
3) State the contents of the femoral triangle from lateral to medial
Femoral nerve, femoral artery, femoral vein, empty space for venous & lymphatic distension,
lymphatics
NAVEL
4) Describe the muscles of the anterior and medial
muscles of the thigh
5) Describe the blood flow from the descending
aorta to the ankle
6) State the ligaments of the hip joint
-Iliofemoral
-Pubofemoral
-Ischiofemoral
7) Explain the pathology behind a gait with
unilateral pelvic drop
Poor contraction of contralateral gluteus
medius when standing causes excessive pelvic tilt (positive Trendelenburg)
8) List the deep lateral hip rotators from superior to inferior
Piriformis
Gemellus superior
Obturator internus
Gemellus inferior
Obturator externus
Quadratus femoris
9) In which area of the buttock can IM injections be safely administered?
Upper lateral quadrant
10) For each vertebra, state its location in the spine
A
B
C
Thoracic
Lumbar
Cervical
11) Labelled the vertebra below
A – spinous process
B – lamina
C – vertebral foramen
D – body
E – pedicle
F – superior vertebral notch
G – superior articular process
H – transverse process
12)
Name the main ligaments of the knee
Medial & lateral collateral
Anterior & posterior cruciate (PAMs APpLes – Posterior starts
anteriorly on the medial condyle, anterior starts posteriorly on
the lateral condyle of the femur)
13) Describe the muscles of the posterior thigh
14) Describe how cruciate ligament damage is
examined
Anterior & posterior drawer tests
15) List the 3 components of the unhappy triad
Torn ACL, tibial collateral & medial meniscus
16) What is a baker’s cyst?
Abnormal fluid-filled sac of synoial membrane in the
popliteal fossa
17) State the innervation of each compartment of
the thigh and their roots
Anterior – femoral nerve – L2-L4
Posterior – sciatic nerve – L4-S3
Medial – Obturator nerve – L2-L4
18) A driver fractures the proximal end of their right fibula in a car crash and can no longer walk on
their heel. Explain how this has come about
Foot drop – damage to the common fibular nerve near the fracture. This leads to denervation of the
anterior leg and an inability to dorsiflex the foot.
19) Match the leg muscles below with their compartment
 Anterior compartment

Posterior compartment

Lateral compartment












Fibularis longus
Tibialis anterior
Plantaris
Extensor hallucis longus
Soleus
Popliteus
Flexor digitorum longus
Tibialis posterior
Fibularis brevis
Extensor digitorum longus
Flexor hallucis longus
Gastrocnemius
20) List the structures posterior to the medial malleolus from anterior to posterior
Tom, Dick And Very Nervous Harry
Tibialis posterior tendon
Flexor Digitorum longus tendon
Posterior tibial Artery
Posterior tibial Vein
Tibial Nerve
Flexor Hallucis longus tendon
21) Describe Hilton’s Law
Hilton’s Law = the nerve supplying a muscle will also supply the underlying bone
22) Label the tarsals
23) How many cervical, thoracic and lumbar vertebrae are there?
7, 12 and 5 respectively
24) Describe the 3 axial planes of the body
25)
Describe the innervation of shoulder abduction
0-15o = supraspinatus
15-90o = deltoid
90-180o = trapezius and serratus anterior rotate the
scapula laterally
26)
How does long thoracic nerve damage present?
Winged scapula due to lack of impulses to serratus
anterior, which stabilised the scapula against the
ribcage
27) Describe compartment syndrome
If there is a bleed in a space enclosed by fascia of the limbs, pressure builds up and may compress
nerves leading to parathesia (tingling).
28) Draw the brachial plexus from its roots to its branches
29) Describe the 3 parts of the axillary artery
First part – inferior to the clavicle and superior to pec minor
Second part – posterior to pec minor
Third part – inferior to pec minor & continues into the cubital fossa
30) What are the borders of the axilla?
Medial – serratus anterior & thoracic ribs
Anterior – pec major, pec minor & subclavius
Posterior – subscapularis, teres major & latissimus dorsi
31) Which landmark on the developing limb drives its elongation?
Apical ectodermal ridge
32) State the borders of the cubital fossa
Superior – imaginary line between the
epicondyles of the humerus
Medial – lateral border of pronator teres
Lateral - medial border of brachioradialis
33) Name the 4 rotator cuff muscles
Supraspinatus, infraspinatus, teres minor, subscapularis (SITS)
34) List the ligaments of the glenohumeral joint
Intracaspular ligaments: glenohumeral
Extracapsualr ligaments: coracoacromial, coracohumeral, transverse humeral
35) Demonstrate the dermatomes on yourself
Keegan & Garrett Model
Foerster Model
36) Describe the following groups of the anterior compartment of the forearm:
Superior group (medial to lateral): flexor carpi ulnaris, palmaris longus, flexor carpi radialis, pronator
teres
Intermediate group: flexor digitorum superficialis
Deep group: flexor digitorum profundus, flexor pollicis longus & pronator quadratus
37) Briefly describe the muscular areas of the upper limb innervated by each of the following:
Musculocutaneous nerve – arm flexors
Radial nerve – posterior arm & forearm
Median nerve – flexors in the anterior forearm except FCU & FDP. Also innervates thenar muscles,
lateral 2 lumbricals, lateral 2 interossei & lateral half of FDP
Ulnar nerve – FCU, medial half of FDP, medial 2 lumbricals, medial 2 interossei & hypothenar muscles
38) Distinguish between tennis elbow and golfer’s elbow
Tennis elbow = lateral epicondylitis
Golfer’s elbow = medial epicondylitis
39) Which ligament prevents dislocation of the radial head?
Ulnar collateral ligament
40) Describe a Colles’ fracture
-A colles’ fracture traverses the entire width of the radius within 2cm of its distal end
-Usually caused by falling on an oustretched hand
-Leads to a dinnerfork deformity due to posterior displacement of the distal fragment
41) Describe the superficial and deep groups of the posterior compartment of the forearm
42) Which nerve is at risk in a shoulder dislocation and how is this tested?
Axillary nerve – tested at its peripheral nerve territory on the lateral arm in the regimental badge area
43) How does denervation to the medial lumbricals and flexor digitorum profundus present?
Ulnar claw
44) Which tendons pass through the carpal tunnel?
4 tendons of flexor digitorum superficialis
4 tendons of flexor digitorum profundus
1 tendon of palmaris longus
45) Name the test used to diagnose carpal tunnel syndrome and explain how it works
Phalen’s test
Forced flexion of the dorsal wrists against each other. This causes increased pressure in the carpal
tunnel. Positive test = paraesthesia of the median nerve
46) Give 5 causes of carpal tunnel syndrome
Myxoedema
Edema (oedema) premenstrually
Diabetes
Idiopathic
Acromegaly
Neoplasm
Trauma
Rheumatoid arthritis
Amyloidis
Pregnancy
47) List the thenar and hypothenar muscles
Thenar
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
Aductor pollicis longus (originates in forearm)
Hypothenar
Opponens digiti minimi
Abductor digiti minimi
Flexor digiti minimi brevis
48) Demonstrate hand of benediction on yourself and explain
how it comes about
Median nerve damage leads to:
-Loss of flexion at PIP of digits 1-3 due to denervated FDS
-Loss of flexion at PIP of digits 4 & 5 due to denervated FDP
-Loss of flexion at MCP of digits 2-3 due to denervated
lumbricals
49) Which tendons create the anatomical snuffbox and which artery can be palpated here?
Tendons of abductor pollicis longus, extensor pollicis longus & extensor pollicis brevis
Radial artery