Posterior compartment of leg
| Posterior compartment of leg | |
|---|---|
| Details | |
| Artery | posterior tibial artery |
| Nerve | tibial nerve |
| Identifiers | |
| Latin | compartimentum cruris posterius |
| TA98 | A04.7.01.006 |
| TA2 | 2654 |
| FMA | 45167 |
| Anatomical terminology | |
The posterior compartment of the leg is one of the fascial compartments of the leg and is divided further into deep and superficial compartments.
Structure
Muscles
Deep posterior compartment
| Muscle | Origin | Insertion | Innervation | Main Action |
|---|---|---|---|---|
| Flexor hallucis longus | Inferior two-thirds of posterior surface of fibula; inferior part of interosseous membrane | Base of distal phalanx of big toe (hallux) | Tibial nerve (S1, S2) |
Flexes big toe at all joints; weakly plantarflexes ankle; supports medial longitudinal arch of foot |
| Flexor digitorum longus | Medial part of posterior surface of tibia; by a broad tendon to fibula | Bases of distal phalanges of lateral four digits | Flexes lateral four digits; plantarflexes ankle; supports longitudinal arches of foot | |
| Tibialis posterior | Interosseous membrane; posterior surface of tibia inferior to soleal line; posterior surface of fibula | Tuberosity of navicular, cuneiform, cuboid, and sustentaculum tali of calcaneus; bases of 2nd, 3rd, and 4th metatarsals | (L4, L5) |
Plantarflexes ankle; inverts foot |
| Popliteus | Lateral surface of lateral condyle of femur and lateral meniscus | Posterior surface of tibia, superior to soleal line | (L4, L5, S1) |
Weakly flexes knee and unlocks it by rotating femur 5 deg on fixed tibia; medially rotates tibia of unplanted limb |
Superficial posterior compartment
| Muscle | Origin | Insertion | Innervation | Main Action |
|---|---|---|---|---|
| Gastrocnemius | Lateral head: lateral aspect of lateral condyle of femur Medial head: popliteal surface of femur; superior to medial condyle |
Posterior surface of calcaneus via calcaneal tendon | Tibial nerve (S1, S2) |
Plantarflexes ankle when knee is extended; raises heel during walking; flexes leg at knee joint |
| Soleus | Posterior aspect of head and superior quarter of posterior surface of fibula; soleal line and middle third of medial border of tibia; and tendinous arch extending between the bony attachments | Plantarflexes ankle independent of position of knee; steadies leg on foot | ||
| Plantaris | Inferior end of lateral supracondylar line of femur; oblique popliteal ligament | Weakly assists gastrocnemius in plantarflexing ankle |
Blood supply
Innervation
The posterior compartment of the leg is supplied by the tibial nerve.
Function
- It contains the plantar flexors:[4]
References
- ^ Moore, Dally, and Agur (2014). Moore Clinically-Oriented Anatomy, Table 5.13.II, p 598.
- ^ https://www.msu.edu/user/vosskurt/Miscellaneous%20pages/musloc.htm
- ^ Moore, Dally and Agur (2014). Moore Clinically-Oriented Anatomy, Table 5.13.I, p 597.
- ^ postleg at The Anatomy Lesson by Wesley Norman (Georgetown University)
