Lateral Compartment of the Leg Flashcards
(45 cards)
1
Q
Lateral compartment of the leg formed by
A
- Fibula
- Anterior/posterior intermuscular septa
2
Q
Muscles of lateral compartment
A
- Fibularis longus
- Fibularis brevis
- Peroneus (fibularis) quartus
3
Q
Muscles of the lateral compartment attach
A
- Proximally to lateral fibular shaft
4
Q
Lateral compartment tendons are visible at
A
- Lateral ankle
- Posterior to lateral malleolus (retromalleolar groove)
5
Q
Lateral compartment muscles function
A
- Evertors
- Aid in plantarflexion
6
Q
Lateral compartment muscles innervated by
A
- Superficial fibular nerve
7
Q
Blood supply to lateral compartment
A
- Perforating branches from fibular artery and anterior tibial
- Branches pierce the intermuscular septa
- No major artery located in the lateral compartment
8
Q
Fibularis longus origin
A
- Fibular head
- Proximal ½ of lateral fibular shaft
- Crural fascia
9
Q
Fibularis longus insertion
A
- Lateral/plantar aspect of medial cuneiform
- 1st metatarsal (tuberosity)
10
Q
Fibularis longus pathway
A
- Posterior to lateral malleolus within fibular groove
- Deep to superior fibular retinaculum
- Inferior to peroneal (fibular) trochlea, deep to inferior fibular retinaculum
- Fibular sulcus and groove of cuboid (inferior surface), crosses sole of foot to insert on medial side
11
Q
Groove of cuboid
A
- Converted to tunnel by the long plantar ligament
12
Q
Fibularis longus function
A
- Eversion and plantarflexion
- (Pronates subtalar and midtarsal joints)
- Helps support 1st metatarsal during during propulsion
13
Q
Fibularis brevis origin
A
- Distal ½ of lateral fibular shaft and crural fascia
- Originates medial and inferior to fibularis longus
- Anterior to fibularis longus as they pass around the lateral malleolus
14
Q
Fibularis brevis insertion
A
- Styloid process of 5th metatarsal
15
Q
Fibularis brevis pathway
A
- Posterior to lateral malleolus (anterior to fibularis longus tendon)
- Deep to superior fibular retinaculum
- Superior to peroneal trochlea, deep to inferior fibular retinaculum
- Heads anteriorly toward its insertion
16
Q
Fibularis brevis tendon is located
A
- Anterior to fibularis longus tendon at the ankle
17
Q
Fibularis brevis function
A
- Eversion and plantarflexion
- (Pronation of subtalar joint)
18
Q
Peroneus (fibularis) quartus
A
- Common accessory muscle (10-26%)
19
Q
Peroneus (fibularis) quartus origin can be either
A
- The actual muscle belly of fibularis brevis or fibularis longus
- Lateral fibular shaft between origins of the fibularis longus and brevis
20
Q
Peroneus (fibularis) quartus insertion
A
- Retrotrochlear eminence
- Cuboid
- 5th met base
21
Q
Peroneus (fibularis) quartus can cause
A
- Overcrowding of the retromalleolar region/fibular groove
- This can cause degeneration/dislocation of the fibularis brevis
22
Q
Synovial sheaths of lateral compartment muscle tendons
A
- Fibular synovial sheath
- Superior/inferior fibular (peroneal) retinacula
23
Q
Fibular synovial sheath
A
- Begins immediately superior to lateral malleolus (~4cm above)
- Divides at fibular trochlea
- Ends at the level of the cuboid
24
Q
Fibular synovial sheath tendons share
A
- A sheath proximally as they pass posterior to lateral malleolus in the retromalleolar groove
25
Fibular synovial sheath are separated by
- Fascial extensions of the inferior fibular retinaculum that attaches to peroneal trochlea
26
The fibularis longus tendon has a synovial sheath
- As it passes along the plantar foot
| - May or may not communicate with the proximal fibular synovial sheath
27
Fibular (peroneal retinacula)
- Thickening of crural fascia and deep fascia of the foot (pedis fascia)
- Anchor tendons of lateral compartment
28
Superior fibular retinaculum
- Continuous with superior extensor retinaculum (transverse crural ligament)
- Creates pulley for tendons as they pass posterior to lateral malleolus
29
Superior fibular retinaculum attaches
- Posteroinferior lateral malleolus
| - Retrotrochlear eminence
30
Inferior fibular retinaculum
- Continuous with stem (frondiform ligament) of inferior extensor retinaculum
31
Inferior fibular retinaculum attaches
- Sinus tarsi
- Peroneal trochlea
- Lateral calcaneus
32
Lateral compartment blood supply
- Branches from fibular and anterior tibial arteries penetrate through the anterior and posterior intermuscular septa
33
Lateral compartment nerve supply
- Common fibular nerve (L4-S2)
| - Superficial fibular nerve (L4-S1)
34
Common fibular nerve (L4-S2) pathway
- From sciatic nerve
- Passes around fibular neck
- Enters lateral compartment by passing through posterior intermuscular septum
- Pierces through fibularis longus
- Bifurcates
35
Common fibular nerve (L4-S2) bifurcates into terminal branches
- Deep fibular nerve
| - Superficial fibular nerve
36
Superficial fibular nerve (L4-S1) pathway
- Arises from common fibular in the lateral compartment
- Descends between the fibularis muscles
- Pierces anterolateral crural fascia in the distal 1/3 of leg
37
Superficial fibular nerve (L4-S1) supplies
- Lateral compartment muscles
| - Cutaneous innervation to distal anterolateral leg, dorsum of foot
38
Branches of superficial fibular nerve (L4-S1)
- Medial dorsal cutaneous nerve
| - Intermediate dorsal cutaneous
39
Medial dorsal cutaneous nerve supplies
- Dorsomedial midfoot
- Cutaneous to medial hallux and adjacent 2nd and 3rd digit
- Branches will give rise to 3 digital branches
40
Intermediate dorsal cutaneous
| supplies
- Dorsolateral midfoot
- Cutaneous to adjacent 3rd and 4th, 4th and 5th digits
- Branches will give rise to 4 digital branches
41
Branches of medial dorsal cutaneous
- Proper dorsal digital nerve 1 (dorsomedial hallux)
- 1st common dorsal digital nerve (2nd intermetatarsal space)
- 4th proper dorsal digital nerve (dorsolateral 2nd toe)
- 5th proper dorsal digital nerve (dorsomedial 3rd toe)
42
Branches of intermediate dorsal cutaneous nerve
- 2nd common dorsal digital nerve (3rd intermetatarsal space)
- 6th proper dorsal digital nerve (dorsolateral 3rd toe)
- 7th proper dorsal digital nerve (dorsomedial 4th toe)
- 3rd common dorsal digital nerve (4th intermetatarsal space)
- 8th proper dorsal digital nerve (dorsolateral 4th toe)
- 9th proper dorsal digital nerve (dorsomedial 5th toe)
43
Lateral dorsal cutaneous (after lateral malleolus)
- Continuation of sural
| - Supplies lateral foot border
44
Branch of lateral dorsal cutaneous nerve
- 10th proper dorsal digital nerve (dorsolateral 5th toe)
| - Continuation of lateral dorsal cutaneous
45
Saphenous nerve supplies
- Medial midfoot/arch and medial ankle
