Lower Limb

Question 1

What Roots Make up the Lumbar Plexus?

How many major peripheral nerves does it give off?

And where is it located?

Answer 1

T12-L4

Gives off 6 major peripheral nerves -

iliohypogastric,

ilioinguinal,

genitofemoral,

lateral cutaneous nerve of the thigh,

obturator nerve,

femoral nerve

Located within the psoas major muscle and anterior to the transvers processes of the lumbar vertebrae

Question 2

What roots does the iliohypogastric nerve contain?

What is its course?

and what is its motor and sensory function?

Answer 2

Roots: T12, L1

Path: Runs to the iliac crest, across the quadratus lumborum muscle of the posterior abdominal wall then perforates transferse abdominis and divides into terminal branches

Motor:

Innervates internal oblique and transverse abdominis

Sensory: innervates posterolateral gluteal skin in the pubic region

Question 3

What root does the ilioinguinal nerve contain?

What is its course?

and what is its motor and sensory function?

Answer 3

L1

Path is same as iliohypogastric nerve. In anterior abdominal wall, lies between internal oblique and transversus abdominis. Peirves internal oblique and passes under external oblique through the superficial inguinal ring

Motor Function:

Innervates internal oblique and transversus abdominis (Same as iliohypogastric n.)

Sensation:

Innervates upper middle thigh,

Males: the root of penis and anterior 1/3 scrotum

Females - mons pubis and labia majora

Question 4

What roots does the genitofemoral nerve contain?

What is its course?

and what is its motor and sensory function?

Answer 4

Roots: L1,L2

Path: After leaving the psoas major muscle, it divides into:

i) genital branch - enters spermatic cord, doesnt go to skin
ii) femoral branch (L1 only) - runs down external iliac artery. Passes beneath the inguinal ligament into the femoral sheath and passes anteriorly through it to supply the femoral triangle skin

Motor:

Genital Branch enters spermatic cords and inervats cremasteric reflex and doesnt reach skin

Sensory:

Femoral branch innervates the skin on the upper anterior thigh

Question 5

What roots does the Lateral Cutaneous Nerve of the Thigh contain?

What is its course?

and what is its motor and sensory function?

Answer 5

Roots: L2,3

Path: Lateral border of the psoas, incorporated within iliac fascia, lites in a firbous tunned a cm medial to the ASIS. Enters thigh at lateral aspect of the inguinal ligament, where it provides cutaneous innervation to the skin. Enters thigh deep to fascia lata and divides into anterior (L3) and posterior (L2) branches.

No motor function

Sensation: innervates the anterior and lateral thigh down to the level of the knee

Question 6

What roots does the Obturator Nerve contain?

What is its course?

and what is its motor and sensory function?

Answer 6

Roots: Anterior divisions of anterior rami L2,3,4

Path: Emerges at medial border of psoas, runs posterior to iliac arteries and laterally to the obturator foramen. It then enters the thigh through the obturator canal and splits into anterior and posterior divisions

Anterior division descends between adductor longus and brevis then pierces the fascia latal to become the cutaneous branch of the obturator nerve

The postrior division descends through the obturator externis muscle before passing anteriorly to adductor magnus and the capsule of the knee joint

Motor:

Innervates the obturator externus, pectineus, adductor longus, adductor brevis, adductor magnus, gracilis

Sensory:

Innervates the skin over the medial thigh

Question 7

What roots does the femoral nerve contain?

What is its course?

and what is its motor and sensory function?

Answer 7

Roots: L2,3,4

Path:

Descends through psoas major muscle. Lies in the fossa between the psoas and illiacus. The nerve then travels underneath the inguinal ligament into the thigh to the femoral triangle where it is lateral to the femoral vessels.

4cm below the inguinal ligament it divides into anterior and posterior divisions:

• Anterior

Medial femoral cutaneous nerve L2,3 (supply medial thigh)

Intermediate femoral cutaneous nerve L2,3 (Supply anterior thigh)

branch to sartorius, branch to pectineus

• Posterior

(Saphenous nerve, branches to quadriceps femoris).

The terminal branch is the saphenous nerve which continues, with the femoral atery and vein

Motor:

Anterior thigh muscles - iliacus, pectineus, sartorius, rectus femoris, vastus lateralis, vastus medialis, vastus intermedius

Sensory:

Skin of the anterior thigh (anterior cutaneous branch) and medial leg (saphenous nerve)

Question 8

What forms the patellar plexus

Answer 8

Network of nerves near the patellar

Formed by the terminal branches of the medial and intermediate femoral cutaneous nerves of the femoral nerve, the lateral femoral cutaneous nerve and the infrapatellar branch of the saphenous nerve

Question 9

What nerve roots form the sacral plexus?

What nerves arise from it?

Answer 9

Roots: L4,L5, S1-S4

Located on the surface of the posterior pelvic wall, anterior to the piriformis muscle. The nerve roots have one of two destinations:

i) Remain in the pelvis
ii) Leave pelvis via the greater sciatic foramen

Gives rise to:

1. Superior Gluteal Nerve
2. Inferior gluteal nerve
3. Sciatic Nerve
4. Posterior femoral nerve
5. Pudendal nerve

Question 10

Sacral plexus:

What roots does the Superior gluteal nerve contain?

What is its course?

and what is its motor and sensory function?

Answer 10

L4,L5,S1

Path:

Leaves pelvis via greater sciatic foramen, entering gluteal region superiorly to the piriformis muscle (accompanied by the superior gluteal artery and vein)

Motor function:

innervates gluteus minimus, gluteus medias and tensor fascia lata

No sensory function

Question 11

Sacral plexus:

What roots does the Inferior gluteal nerve contain?

What is its course?

and what is its motor and sensory function?

Answer 11

L5,S1,S2

Path: Leaves pelvis via greater sciatic foramen, intering gluteal region inferiorly to piriformis (accompanies inferior gluteal artery and vein)

Motor: Gluteus maximus

No sensory function

Question 12

Sacral plexus:

What roots does the Sciatic nerve contain?

What is its course?

and what is its motor and sensory function?

Answer 12

L4,L5, S1, S2,S3

Path: Leaves pelvis via greater sciatic foramen into gluteal region. Emerges inferiorly to the piriformis muscle. Crosses posterior to obturator internus. Enters posterior thigh by passing deep to long head of bicep femoris.

Motor:

Innervates muscles of posterior compartment of thigh + hamstring component of adductor magnus (apart from short head of biceps femoris)

*Nerve gives off tibial and common fibular nerve

Question 13

The tibial nerve.

What is its course?

and what is its motor and sensory function?

Answer 13

Path:

Tibial nerve is a branch of the sciatic nerve, and arises at the apex of the popliteal fossa

Travels posterior leg, between heads of gastrocnemius, deep to soleus, supplying posterior leg muscles and sural nerve (sensory lateral post. leg)

At foot it passes posteriorly and inferiorly to the medial malleoulus through the tarsal tunnel

Terminates by dividing into 3 sensory branches (Medial calcaneal, medial plantal and lateral plantar nerve)

Motor:

• Posterior compartment of leg and muscles in the sole of the foot
• Deep (Popliteus, flexor hallucis longus, flexor digitorum longus, tibialis posterior)
• Superficial (Plantaris, Soleus, gastrocnemius)

Sensory:

• Posterolateral leg (sural nerve) and posterolateral + medial surfaces of the foot and sole of foot (medial calcaneal branch, lateral and medial plantar nerve)

Question 14

The common peroneal nerve

What is its course?

and what is its motor and sensory function?

Answer 14

Path:

From sciatic nerve. Begins at apex of popliteal fossa, where sciatic nerve bifurcates

Follows medial border of biceps femoris, running in a lateral, inferior direction over lateral head of gastrocnemius and fibular origin of soleus

Here it gives of two cutaneous branches

i) Peroneal communicating nerve (combines with sural nerve from tibial n.)
ii) lateral cutaneous nerve
iii) Superior and inferior genicular nerves
iv) recurrent genicular nerve

The nerve wraps around the neck of the fibula, passing between the attachments of the fibularis longus muscle.

Here the nerve terminates into a superfiical peroneal and deep peroneal nerve

i) superficial peroneal nerve - innervates muscles of the lateral compartment of leg (acting to evert the foot) and dorsal foot, anterolateral leg
ii) Deep fibular nerve - innervates the muscles of the anterior compartment of the leg (acting to dorsiflex the foot, extend digits) and dorsal foot

Summary:

Motor - All muscles in anterior and lateral compartments

Sensory - skin on anterolateral surface of the leg and dorsal aspect of the foot

Question 15

Sacral plexus:

What roots does the Posterior Femoral Cutaneous Nerve contain?

What is its course?

and what is its motor and sensory function?

Answer 15

Roots: S1,2,3

Path:

Leaves pelvis via greater sciatic foramen, entering gluteal region inferiorly to piriformis muscle

Descends deep to gluteus maximus and runs down back of thigh to knee

No Motor Function

Sensory: Innervates skin of the posterior surface of the thigh and perineum

Question 16

What roots does the Pudendal nerve contain?

What is its course?

and what is its motor and sensory function?

Answer 16

Roots S2,3,4

Leaves pelvis via greater sciatic foramen then re-enters via the lesser sciatic foramen

Moves anteriosuperiorly along the lateral wall of the ischiorectal fossa, and terminates dividing into several branches

(Nerve to piriformis, obturator internus, quadratus femoris)

Motor:

Innervates skeletal muscles in peroneum, external urethral sphincter, external anal sphincter, levator ani

Sensory:

Penis/ clitoris

Question 17

Describe the femoral artery, its course and branches

Answer 17

FEMORAL ARTERY

External iliac artery becomes the femoral artery when it crosses under the inguinal ligament at the mid-point between the ASIS and pubic symphysis

On top of the psoas muscle

Emerges from femoral sheath and continues down anterior surface of thigh under sartorius, via adductor canal (which ends at the opening of adductor magnus - called the adductor hiatus). Femoral a. moves through this opening and enters the posterior thigh. Proximal to entering the posterior knee it becomes the POPLITEAL ARTERY,

Branches:

Gives off profunda femoris in femoral triangle

It gives off 3 main superficial arteries just below the inguinal ligament

1 Superficial iliac circumflex aryery

2 Extenral pudendal artery

3 profunda femoris

PROFUNDA FEMORIS

Given off in In the femoral triangle 4cm below inguinal ligament. Then spirals deep to adductor longus. The profunda femoris artery arises from the posterolateral aspect of the femoral artery. This gives off 3 branches:

i) Medial femoral circumflex artery (post. femur, suppyling neck and head. It can be easily damaged ina NOF)
ii) Lateral femoral circumflex artery
a) Ascending branch (runs up vastus lateralis - gives branch to trochanteric anastaomosis then goes to ASIS and anastomoses with circumflex iliac arteries) Must be careful in anterior approach to THR going between sartorius and tensor fascia lata not to hit this.
b) Transverse branch - winds around femur
c) Descending branch
iii) Perforating branches –> muscles in posterior/ medial thigh

Question 18

Describe the internal iliac arteries supply of the leg and its branches

Answer 18

Internal iliac arterty gives off:

1) Gluteal region supplied by superior and inferior gluteal arteries (passes under and over piriformis with corresponding nerve)
2) Obturator artery - which breaks into a posterior and anterior branch
i) anterior - pectineus, obturator externus, adductor muscles, gracilis
ii) posterior - deep gluteal muscles

Question 19

Describe the Popliteal artery course and its branches

Answer 19

Popliteal artery descends posterior thigh, through popliteal fossa, exits between gastrocnemius and popliteus muscles.

Gives off the sural arteries that supply heads of gastrocnemius and the genicular arteries which supply the knee.

At the border of the popliteus it divides into anterior and posterior tibial arteries

i) Anterior tibial artery which travels through the interosseous membrane of tibia and fibula then becomes dorsalis pedis artery
ii) Posterior tibial artery is accompanied by tibial nerve, deep to the soleus, and enters sole of foot via the tarsal tunnel. Gives off a fibular artey branch in the leg that supplies the lateral compartment of the leg.

Question 20

Describe the arterial system in the foot

Answer 20

Posterior tibial artery enters through tarsal tunnel and splits into lateral and medial plantar arteries which suply plantar foot

Anterior tibial artery becomes the dorsalis pedis (felt between extensor hallus longus and brevis) which anastamoses with the lateral plantar artery to form the deep plantar arch

Dorsalis pedis also gives off branches of dorsum off foot - namely lateral tarsal a. and arcuate a.

Question 21

Describe the deep veins of the leg

Answer 21

Deep veins accompany major arteries

Dorsal venous arch –> anterior tibial vein

Medial and lateral plantar veins –> posterior tibial and fibular veins

anterior tibial, posterior tibial and fibular veins units to form popliteal vein

popliteal vein –> enters thigh via adductor cannal –> femoral vein

The Profunda femoris vein joins the femoral vein, which then leaves the thigh under the inguinal ligament, at which point it is the external iliac vein

Question 22

What are the superficial veins of the leg

Answer 22

Superficial veins found in the subcutaneous tissue

i) Great saphenous vein
- Formed by dorsal venous arch of foot and dorsal vein of great toe.
- Ascends medial side of leg, passing anterior to medial malleoulus of ankle and posterior of medial condyle of knee
- drains into femoral vein immediately inferior to inguinal ligament
- contains 20 valves, mainly below knee
ii) Small saphenous vein
- Formes by dorsal venous arch
- Moves up posterior side of leg, passing poasteriorly to lateral malleolus, along lateral border of calcaneal tendon
- Moves through two heads of gastrocnemius and empties into popliteal vein in the popliteal fossa

Question 23

Superficial arteries of the thigh (4 cutaneous branches of the femoral)

Answer 23

4 branches just below the inguinal ligament

i) superficial circumflex iliac artery (anastamoses near ASIS)
ii) superficial epigastric artery (lower abdo wall)
iii) superficial external pudendal artery (scrotum)
iv) deep external pudendal artery (scotum)

Question 24

Lymph Nodes of lower limb

Answer 24

Lymph atcs accompany the great saphenous vein

Superficial inguinal nodes (In the subcutanous fat of femoral triangle - has 3 groups

i) vertical - deep fascia and everything superficial of lower limb
ii) Lateral- buttock, flank, back below waist
ii) medial - below umbilicus and medial to ASIS

The efferent lymphatics from these groups pass through the cribriform fascia to enter the deep inguinal nodes

Question 25

What is the fascia lata What two muscles does it enclose fully?

Answer 25

Fascia lata is the deep fascia that encloses the thigh Imaging a stocking - form the top it attaches from ASIS, around external lip of iliac crest (as far back as the posterior gluteal line, where it splits to enclose the gluteus maximus and attaches on the origin on the ilium and sacrum that the gluteus maximus has. It then traces around the ischial tuberosity, ischiopubic ramus and body of the pubic bone The fascia lata is attached below to the patella and inferior margins of the tibial condyles and head of fibula The fascia lata encloses two muscles - the gluteus maximus and the tensor fasciae lata

Question 26

What is the saphenous opening and what structures go through the saphenous opening

Answer 26

Saphenous opening is an opening in the fascia lata it occurs approx 3.5cm inferior/lateral to the pubic tubercle The lymphatic vessels and greater saphenous vein go through the opening it is overlied by **cribriform fascia**

Question 27

Iliotibial tract

Answer 27

Origin: Thickening of the fascia lata that commences at the level of the greater trochanter where 3/4 of the gluteus maximus and tensor fasciae lata are inserted into it Insertion: Anterior surface of lateral condyle of tibia Function: When the knee is straight the tract passes in fron of the axis of flexion thus maintains the knee in hyperextended position (Not an extensor of the flexed knee) Important in walking with a minimally flexed knee and extending knee when standing up Also similar to gluteus medius and minimus - abducting and medially rotating hip Note the lateral intermuscular septum attaches to the tract which in turn connects it to the linea aspera of the femur Surface Anatomy: The bulge of vastus lateralis is seen anterior to the iliotibial tract

Question 28

Tensor Fascia Lata - Origin - Attachment - Innervation - Function

Answer 28

Origin: - External lip of iliac creast between the ASIS and tubercle of the crest Insertion: iliotibial tract Innervation: Superior gluteal nerve (L4,5,S1) Action: Pull upon iliotibial tract which by extending knee joint, stablisation

Question 29

Femoral Triangle - Borders - Contents

Answer 29

_Borders:_ Superior - Inguinal Ligament - Lateral - Sartorius - Medial - Adductor Longus - Roof - Fascia Lata - Floor - Pectineus, iliopsoas _Contents_ (Lateral to medial) - Femoral nerve - Femoral artery - Femoral Vein - Femoral canal (Contains deep lymph nodes and vessels) \*The femoral artery, vein and canal are in a femoral sheath

Question 30

What is the femoral sheath and its contents? And what is crifriform fascia?

Answer 30

Prolongation of the extraperitoneak fascia derived from the transversalis fascia and psoas fascia Contains the femoral artery and vein There is a small space **medial to the vein** in the sheath - called the femoral canal which transmits lymphatic vessels and allows the femoral vein to expand The canal contains the lymph node of Cloquet which drains the clitoris/ penis The anterior wall is peirced by the femoral branch of the genitofemoral nerve

Question 31

In regards to pectineus muscle. How to the following structures relate to it: Adductor brevis Obturator nerve Femoral Vein Femoral Canal

Answer 31

Deep to pectineus: Adductor brevis, Obturator nerve inbetween adductor brevis and behind pectineus Superficial: Femoral canal and vein

Question 32

What is the femoral ring and whats a femoral hernia

Answer 32

The femoral ring is the opening of the femoral canal at its abdominal end 4 boundaries: Anterior - Medial inguinal ligament Medial - Crescenteric edge of lacunar ligament Posterior - pectineal ligament and pectineus Lateral - femoral vein it is usually closed by the femoral septum (fusion of iliopectineal fascia and transversalis fascia), however... Significance: a femoral hernia enters the canal through this ring (the lacunar ligament may have to be incised to release a stangulated hernia) It then inters the groing and passes through the saphenous opening... thus the hernia is covered in fascia of the femoral seeptum and cribiform fascia and fat (which can make cough impulse test less obvious)

Question 33

Potential Complications of femoral artery cannulation

Answer 33

Retroperitoneal haemorrhage Perforation of gut Arteriovenous fistula (with the femoral and external iliac vein)

Question 34

Anterior Thigh Muscles - Origin - Attachment - Innervation - Function

Answer 34

Question 35

Adductor cannal - Border - Contents

Answer 35

Borders - Anterior - Sartorius - Lateral - Vastus medialis - Medial - Adductor longus (above) and magnus (below) Contents: - Saphenous Nerve - Nerve to vastus medialis - Femoral Artery and vein (as they leave the canal they become the popliteal vein and artery) \*Skin overlying is supplied by the subsartorial plexus (Fibres from intermediate cutaneous nerve of thigh, saphenous nerve, anterior division of obturator nerve)

Question 36

What is the medial and lateral intermuscular septum of the thigh

Answer 36

The medial intermuscular septum divides the Medial and anterior compartment of the thigh The medial intermuscular septum of thigh is a fold of deep fascia in the thigh. It is between the vastus medialis, and the adductors and pectineus. It is thinner than the lateral septum

Question 37

Medial (Adductor) compartment of thigh - origins - attachment - innervation - function

Answer 37

Question 38

Cutaneous nervve supply to gluteal regions

Answer 38

cluneal nerve - derived from posterior rami of L1-3 and S1-5 Then the anterior rami of Also iliohypogastric nerve on lateral side and lateral femoral cutaneous nerve

Question 39

Superficial gluteal muscles - origin - attachment - innervation - function

Answer 39

Question 40

What is the greater sciatic foramen?

Answer 40

An opening in the posterior pelvis. It is formed by the sacrotuberous (Sacrum --\> ischial tuberosity) and Sacrospinous (Sacrum --\> Ischial spine) Ligaments The piriformin muscle passes through and occupies most its volume What passes through it? i) Passing over the piriformis is the superior gluteal nerve and vessels ii) Passing below the piriformis is: a) he inferior gluteal nerve and vessels b) the pudendal nerve and vessels c) the nerve to obturator internus d) and the sciatic nerve with the posterior femoral cutaneous nerve on its surface and the nerve to quadratus femoris deep to it

Question 41

Whats the lesser sciaitic foramen

Answer 41

between the sacrospinous and sacrotuberous ligaments, and below the greater sciatic foraemen the obturator internus passes through this as it wraps aorund to insert on the greater trochanter

Question 42

Deep muscles in gluteal region - origin - attachment - innervation - function

Answer 42

Question 43

Hip Joint - Ligaments - Neurovasc

Answer 43

Synoial joint between femur and acetabulum (deepened by acetabular labrum made of fibrocartilage then continues as transverse ligament) Capsule is attached circumfrentially around labrum and transverse ligament, attaching to neck of femur Ligaments: Intracapsular - ligament of head of femur (Acetabular fossa to fovea of femur, enclosing a branch of the obturator artery) Extracapsular i) Iliofemoral (AIIS - tranchanteric line of femur) ii) Pubofemoral (Superior pubic fami - intertrochanteric line of femur) iii) Ischiofemoral (Ischium - greater trochanter) Vasc: - Mainly **Medial** and some lateral circumflex femoral arteries (Fromprofunda femoris) - Inferior/superior gluteal arteries + obturator artery through ligament of head of femur (usually closes age 7) provide some additional supply Neves (hiltons law) - femoral, sciatic, obturator

Question 44

Muscles involved in flexion at the hip

Answer 44

Mainly: Psoas Illiacus Assistance from - rectus femoris, tensor fasciae lata, sartorius, pectineus

Question 45

Muscles involved in extention of the hip

Answer 45

Gluteus maximus (at extremities) Hamstrings (immediate stage)

Question 46

Muscles involved in adduction of leg

Answer 46

Gracilis Adductor brevis, longus, magnus Pectineus

Question 47

Muscles involved in abduction of the hip

Answer 47

Gluteus medius, minimis piriformis

Question 48

What causes lateral and medial rotation of hip

Answer 48

Lateral (muscles that attach behind hip) - piriformis, obturator interus, gemelli, quatratus femoris, obturator externus, glut maximus Medial rotation: - gluteus medius, minimus - assisted by adductors and tensor fascaie lata

Question 49

Posterior componant of thigh - origin - attachment - innervation - action

Answer 49

Question 50

Popliteal fossa - border - contents

Answer 50

Borders - Superiomedial - Semimembranous and semitendinous - Superiolateral - Biceps femoris - Inframedial and lateral - heads of the gastrocnemius - roof - fascia lata (peirced by small saphenous vein and posterior femoral cutaneous nerve) - Floor - popliteal surface of femur and capsule of knee joint and popliteus Contents - Popliteal artery (deepest structure) - Popliteal vein (small saphenous vein empties in here) - Tibial nerve - Common fibular nerve (follows biceps femoris tendon, running lateral margin of fossa) - popliteal lymph nodes

Question 51

What two structures enter the posterior joint capsule of the knee?

Answer 51

Middle genicular artery --\> supplies cruciate ligaments genicular branch of obturator nerve

Question 52

What are the two main gaps in the knee capsule

Answer 52

one allowing popliteus tendon to enter, the other communicating with the suprapatellar bursa

Question 53

Describe the ligamenture of the knee

Answer 53

**Extracapsular Ligaments** _1) Patellar retinacula_ (patella to lower condyles on tibia, fibrous extention of quad tendon) a) Medial patella retinaculm b) Lateral patella retinaculum _2) Collateral Ligaments_ a) Lateral collateral ligament (Lateral epicondyle femur - lateral surface of fibular head. Lies free from capsule and lateral meniscus, seperated by popliteus) b) Medial collateral ligament (medial epicondyle femur - medial surface tibia. Attaches to medial meniscus) _3) Oblique Poplital Ligament_ _4) Arcuate Poplital Ligament_ _5) lateral and medial patellofemoral ligament_ **Intra-articular ligaments:** 1) Anterior Cruciate Ligament (Anterior tibial plateau -\> smooth impression on posterior lateral condyle of femur in the intercondylar notch) 2) Posterior Cruciate Ligament (posterior tibia between condyles --\> passes forward onto a smooth impreeion on the medial epicondyle, well forward of intercondylar notch) 3) Medial and Lateral Menisci (blood supply from periphery) 4) Transverse Ligament (between anterior horns of both menisci) 5) Meniscofemoral ligament (anterior and posterior, associated with lateral meniscus) 6) Lateral and Medial meniscotibial ligaments

Question 54

important Bursae of the knee

Answer 54

1) Suprapatellar bursa (extension of synvial cavity, located between quadriceps femoris and femur) 2) Prepatella burrsa (apex of patella and skin) 3) Infrapatella bursa - between tibia and patella ligament 4) Semimembranous bursa (between semimembranous and medial gastrocnemisu)

Question 55

blood and nerve supply to knee

Answer 55

blood - genicular arteries nerve - femoral, common peroneal, tibial, obturator nerve (Hiltons law) (Cruciate ligements - tibial nerve sensation)

Question 56

What three nerves supply the skin of the (lower) leg?

Answer 56

Lateral half --\> Common perineal nerve (lateral surcral cutaneous nerve) Medial half --\> Femoral nerve (Saphenous nerve) Posterior --\> Tibial nerve (Medial cutaneous nerve)

Question 57

What nerves supply the foots skin?

Answer 57

Dorsal aspect: - Superficial finular nerve (mainly) - Deep fibular nerve (2nd toe) Plantas aspect: - Tibial branches: Calcaneal, medial plantar and lateral plantar nerves Over the lateral malleolus: - Sural nerve (Combination of the medial sural cutaneous nerve of tibial n. and lateral cutaneous nerve of common peroneal n.)

Question 58

What nerves supply the skin to the thigh

Answer 58

Anterior: Femoral nerve (anterior cutaneous branch) Lateral: Lateral femoral cutaneous nerve Medial: Obturator nerve Posterior: Posterior femoral cutaneous nerve Groin: Genitofemoral nerve (Femoral and genital branch) Ilioinguinal Penis: Pudendal nerve

Question 59

Muscles of the anterior compartment of the leg - origin - attachment - innervation - function

Answer 59

Question 60

Muscles of dorsum of foot - origin - attachment - innervation - function

Answer 60

Question 61

Muscles of lateral compartment of leg - origin - attachment - innervation - function

Answer 61

Question 62

Superficial muscles of posterior leg compartment - Origin - Attachment - Innervation - function

Answer 62

Question 63

Deep muscles of the posterior leg

Answer 63

Question 64

What is the tarsal tunnel, what are its borders and contents?

Answer 64

Borders: - Floor - concave surface formed by medial aspect of tibia, talus and calcaneus - covered by flexor retinaculum (which spans obliquely between the medial malleolus and medial tubercle of calcaneus) Contents (Tom, Dick and A Very Nervous Harry) [anterior to posterior] - Tibialis posterior tendon - Flexor digitorum longus tendon - Posterior tibial Artery and Vein - Tibial nerve - Flexor Hallucis longus tendon

Question 65

Describe the plantar aponeurosis

Answer 65

they originate from the medial and lateral tubercles of the calcaneus and from the back of that bone below the insertion of the tendo calcaneus. It fans out over the sole and is inserted by five slips, into each of the five toes. The digital slips bifurcate for the passage of the flexor tendons and are inserted around the edges of the fibrous flexor sheaths and into the transverse ligaments that bind together the metatarsal heads.

Question 66

First Layer of Muscles on Sole of foot - Origin, attachment, insertion,

Answer 66

Question 67

Second Layer of muscles on sole of foot

Answer 67

Question 68

Bones of the foot

Answer 68

Question 69

Third layer of the foot muscles - origin - attachments - innervation - function

Answer 69

Question 70

Fourth Layer of foot muscles

Answer 70

PAD and DAB

Question 71

The ankle joint ligaments

Answer 71

Two sets of ligaments, originating from each malleolus _Medial malleolus:_ Medial (deltoid) ligament (Consists of 4 ligaments), which fan out from malleolus attaching to talus, calcaneus and navicular bone. and attach to spring ligament. Its Purpose is to resist over-eversion of the foot _Lateral malleolus_ - Anterior talofibular - Posterior talofibular - Calcaneofibular

Question 72

Ankle joint movements, blood and nerve supply

Answer 72

Movements: * Plantarflexion – produced by muscles in the posterior compartment of the leg; gastrocnemius, soleus, plantaris and posterior tibialis * Dorsiflexion – produced by the muscles in the anterior compartment of the leg; tibialis anterior, extensor hallucis longus and extensor digitorum longus \*Inversion, eversion at subtalar joint Blood: posterior and anterior tibial arteries Innervation: deep peroneal and tibial nerves

Question 73

Talocalcaneonavicular joint and its ligaments, movements, blood supply and innervation

Answer 73

_Stability_ The subtalar joint is enclosed by a joint capsule, which is lined internally by synovial membrane and strengthened externally by a fibrous layer. 3 ligaments of talocalcaneal (subtalar)part: * Posterior talocalcaneal ligament * Medial talocalcaneal ligament * Lateral talocalcaneal ligament The interosseous talocalcaneal ligament acts to bind the talus and the calcaneus together, it lies within the sinus tarsi. 3 ligaments of talocalcaneonavicular part: - Plantar calcaneonaviculr ligament (spring ligament) - tibionavicular ligament - half the bifurgate ligament _Movements_ * Eversion and inversion movements produced by the muscles of the lateral compartment of the leg and the tibialis anterior muscle respectively _Neurovascular supply_ * Arterial supply comes from the posterior tibial and fibular arteries * Innervation of plantar aspect supplied by the medial or lateral plantar nerve, the dorsal aspect is supplied by the deep fibular nerve

Question 74

Which joint does inversion/ eversion of the ankle take place? and what muscles perform these actions?

Answer 74

Talocalcaneonavicular joint Inverts: - Tibialis anterior (1) - Tibialis posterior (3) Everts: - Peroneus tertius (2) - Peroneus longus (4) hese four combine in groups of two to produce their common movement and cancel out their opposing movements. Thus result dorsiflexion (1 and 2), inver sion (1 and 3), eversion (2 and 4) and plantarflexion (3 and 4) of the foot as a whole

Question 75

What are the three arches of the foot

Answer 75

1. transverse arch 2. medial longitudinal arch 3. lateral longitudinal arch

Question 76

What are the muscles and ligaments involved in the medial arch of the foot

Answer 76

\*if muscles paralysed, ligaments alone cant maintain arch Muscles: Flexor hallucis longus Abductor hallucis Medial half of flexor digitorum brevis Tibialis anterior and posterior Fibularis longus Ligaments: Plantar aponeurosis most important Spring ligament second most important Plantar ligaments (in particular the long plantar, short plantar and plantar calcaneonavicular ligaments)

Question 77

What are the muscles and ligaments involved in the lateral arch

Answer 77

Muscles - fibularis longus - lateral flexor digitorum brevis , flexor digitorum longus - abductor digiti minimi Ligaments - long plantar, short plantar - plantar calcaneonavicular - plantar aponeurosis

Question 78

Transverse arch of foot what forms this

Answer 78

Bones: Cueiform bones Ligaments: plantar ligaments and deep transverse metatarsal ligament, plantar aponeurosis Muscles: peroneus longus and tibialis posteior adductor hallucis muscle

Question 79

Femoral nerve injury presentation

Answer 79

Nerve breaks into branches as soon as it enters thigh so usually subject to damage by penetrating injuries to lower abdomen In a complete lesion - Extension of quadriceps lost - Weakness in hip flexion - Anaesthesia over front of thigh, with lesions that cause pain in the nerve extending potentially to medial side of foot (saphenous branch)

Question 80

how does damage to the lateral femoral cutaneous nerve damage present

Answer 80

No motor function Produces parasthesia (meralgia paraesthetica) to upper lateral thigh

Question 81

How would damage to the obturator nerve present

Answer 81

very rare due to deep position Motor: Loss of adduction. This cannot be noticed when walking, but when sitting the affected limb cant cross over the other Sensation: Parasthesia over medial thigh

Question 82

How does damage to the sciatic nerve present?

Answer 82

commonest cause is by misplaced gluteal injections, then trauma/ hip dislocations Motor There is paralysis of hamstrings and all the muscles of the leg (supplied by tibial and common peroneal nerve) \*Hamstring power can be difficult to assess, but footdrop is obvious Sensory: Parasthesia below knee (but not on medial side of leg as supplied by saphenous nerve)

Question 83

How does damage to the common peroneal nerve present?

Answer 83

Caused by direct trauma or pressure by plaster casts at neck of fibula Motor: - Foot drop (Due to paralysis of extensor muscles by deep peroneal branch). This results in a high step gait - Peroneus longus and brevis also effected (superficial peroneal branch) Sensory: Anaesthesia over lower lateral part of lef and dorsum of foot (But may be little sensory loss)

Question 84

How does damage to the tibial nerve present?

Answer 84

Uncommon Motor: Paralysis of calf muscles (unable to plantarflex). Cant tip toe walk. Sensory: anaesthesia sole of foot

Question 85

Is the acetabulum pointed horizontally?

Answer 85

No, it is directed downwards and slightly backwards

Question 86

Ossification of the hip

Answer 86

The bone develops in cartilage. Three primary centres appear, one for each bone, near the acetabulum. The centre for the weight-bearing ilium appears first, at the second month, followed by the ischium at the third and pubis at the fourth month of fetal life. At birth the acetabulum is wholly cartilage, and while the ilium is a broad blade of bone the ischium and pubis are no more than tiny bars of bone buried in the cartilage. Growth of these three bones causes them later to approximate each other in a Y-shaped cartilage in the acetabulum. The ischial and pubic rami fuse with each other at about 7 years. Around the whole bone there remain strips of hyaline cartilage as follows; the whole length of the iliac crest, anterior inferior iliac spine, body of pubis at the symphysis, ischial tuberosity and sometimes ischial spine. The Y-shaped cartilage begins to ossify at about 12 years, with the appearance within it of two or three small centres of ossification (ossa acetabuli) which enlarge to fuse with each other and the surrounding bones to close the acetabulum soon after puberty (say 15 years). At the same time bony centres appear in the peripheral strips of cartilage. These fuse with the main bone when growth of the whole body ceases (say 25 years).

Question 87

Ossification of femur

Answer 87

The whole femur ossifies in cartilage. A centre in the shaft appears at the eighth week of fetal life. A centre for the lower end appears at the end of the ninth fetal month (at birth) and its presence is accept able medicolegal evidence of maturity. This is the growing end of the bone, and the epiphysis, which bisects the adductor tubercle (Fig. 3.56) unites with the shaft after 20 years. A centre appears in the head at 1 year of age, greater trochanter at 3 and lesser trochanter at 12 years. These upper epiphyses fuse with the shaft at about 18 years of age. Note that the neck of the femur is the upper end of the shaft and ossifies as part of it, not from an epiphysis.

Question 88

ossification of tibia

Answer 88

The shaft ossifies in cartilage from a primary centre that appears in the 8th week of fetal life. The upper epiphysis (the growing end) shows a centre immediately after birth. This joins the shaft at 20 years along the epiphyseal line already noted. A secondary centre for the tuberosity may appear about puberty. The lower epiphysis ossifies at the second year and joins the shaft at 18 years. The epiphyseal line passes a centimetre above the distal end of the shaft and includes the medial malleolus; it is extracapsular.

Question 89

ossification of fibula

Answer 89

The fibula ossifies in cartilage by a centre in\* the shaft which appears in the eighth week. There is an epiphysis at each extremity. The head, the growing end, is exceptional in ossifying later (fourth year) than the lower end (second year). The upper epiphysis fuses with the shaft at 20 years, the lower before this (say 18 years).

Question 90

Whats the simple rule of lymph drainage in the limbs

Answer 90

In each limb the rule applies that superficial lymphatics follow veins, while deep lymphatics follow arteries. The lymph is taken to lymph nodes lying in groin and axilla.

Question 91

What muscles laterally rotate the hip

Answer 91

piriformis obturator internus obturator externus Gemeli (superior and inferior) Quadratus femoris Sartorius

Question 92

What muscles adduct the hip

Answer 92

Adductor brevis, longus, magnus Pectineus Gracillis

Question 93

what muscles abduct the hip

Answer 93

gluteus minimus gluteus medius tensor fascia late

Question 94

what muscles flex the hip

Answer 94

Powerful flexors: psoas and iliacus weaker flexors; rectus femoris sartorius pectineus

Question 95

What muscles cause hip extension

Answer 95

Gluteus maximus Biceps femoris (long head) semitendinous semimembranous

Question 96

what muscles extend the knee

Answer 96

vastus lateralis, medius, intermedius Rectus femoris

Question 97

what muscles can rotate the knee

Answer 97

Medial rotation - Semitendinous - Semimembranous Lateral rotation - biceps femoris

Question 98

what are the ligaments that comprise of the distal tibiofibular syndesmosis

Answer 98

anterior- inferior tibiofibular ligament posterior-inferior tibiofubilar ligament interosseous membrane inferior transverse ligament interossoues ligement

Question 99

What is Scarpa's fascia? And why can a femoral hernia not through Scarpa's fascia

Answer 99

The membranous layer of the superficial fascia of the anterior abdominal wall (Scarpa's fascia, p. 241) extends into the upper part of the thigh just below the inguinal ligament. The attachment extends laterally from the pubic tubercle but below the inguinal ligament. It should be noted that the saphenous opening lies below this line, so that a femoral hernia, emerging from the saphenous opening, can never come to lie in the space beneath Scarpa's fascia. The hernia emerges into ordinary subcutaneous fat and can therefore never become very large.

Question 100

Lower limb dermatomes

Answer 100

Question 101

Femeral Hernia Epidemiology: - More common in which gender?

Answer 101

- More common in females (femoral ring and canal wider in females) - Much less common than inguinal hernias \*For most hernias a truss is not reliable

Question 102

Myotomes of lower limbg

Answer 102

(Start with the forward movement) Hip - Flexion: L2,3 - Extension: L4,5 Knee - Extension: L3,4 - Flexion L5,1 Ankle: - Dorsiflexion: L4,5 - Plantarflexion: S1,2 Inversion L4; Eversion L5, S1 Big Toe: Extension: L5,S1 Flexion: S1,S2

Question 103

What is the cruciate anastomosis?

Answer 103

\*Cruciate means cross The transverse branch of the medial circumflex femoral artery meets the transverse branch of the lateral circumflex artery at the lower border of the quadratus femoris. They are joined by an ascending branch of the first perforating artery and the descending branch of the inferior gluteal artery

Question 104

Whats the trochanteric anastamosis ?

Answer 104

Provides main source of blood supply to femoral head Formed by descending branch of superior gluteal arterywith the ascending branches of both lateral and medial circumflex femoral arteries. (inferior gluteal artery usually joints the anastamosis) Branches from the anastamosis are called the retinacular arteries.

Question 105

The synovial membrane of the knee relation to the cruciate ligaments and bursa

Answer 105

- communication with the suprapatellar bursa has already been noted. - A hernia ion of synovial membrane beneath the rounded tendon of popliteus produces the banana-shaped popliteus bursa lying in the gutter between the tibia and the head of the fibula (Fig. 3.32). (Popliteus bursae communicates with the knee) - The bursa beneath the medial head of gastrocnemius always and that beneath the lateral head usually, communicate with the joint. The bursa under the medial head of gastrocnemius usually communicates also with the semimembranosus bursa The synovial membrane passes infront of the cruciate ligaments.

Question 106

ossification of patella

Answer 106

the bone forms in hyaline cartilage by a centre that appears at 3 years; there is sometimes more than one centre. Ossification is complete soon after puberty.

Question 107

Function of ACL

Answer 107

The anterior cruciate ligament prevents backward displacement of the femur on the tibial plateau, but this is unlikely to happen. The anterior cruciate ligament has a much more important role, that of limiting exten sion of the lateral condyle of the femur and of then causing medial rotation of the femur in the 'screw- home' position of full extension. Extension is performed by the quadriceps and is limited by the tension of the anterior cruciate ligament, the oblique popliteal ligament and the collat eral ligaments, but these four ligaments do not tighten simultaneously. As the knee moves into full extension the anterior cruciate ligament is the first to become taut. Extension of the lateral condyle of the femur is thus termi nated. Further extension of the medial condyle is made possible by passive rotation forwards of the lateral condyle around the radius of the taut anterior cruciate ligament. This forces the medial condyle to glide backwards into its own full extension. The medial condyle has a longer and more curved articular surface than the lateral condyle for this very reason

Question 108

What ventral rami are the tibial and common peroneal divisions of the sciatic nerve derived from?

Answer 108

Tibial nerve - L4,5; S1,2,3 ommon Peroneal - L4,5; S1,2