Muscles of the Posterior Compartment of the Leg

Authors

Affiliations

Nate Yomogida, B.S., SPT

Doctor of Physical Therapy

B.S. in Kinesiology

Chloë Kerstein, B.S., SPT

Doctor of Physical Therapy

B.A. in Neuroscience

Superficial Flexors

Schematic of Superficial Flexors of the Posterior Compartment of the Leg
1: Gastrocnemius
2: Soleus
3: Plantaris¹

Superficial Flexors of the Posterior Compartment of the Leg¹

Superficial Flexors of the Posterior Compartment of the Leg without the gastrocnemius¹

Table 1: Superficial Flexors of the Posterior Lower Leg

Muscle	Origin	Insertion	Innervation	Action
Gastrocnemius	Superior-posterior aspect of Medial Femoral Condyle Lateral surface of Lateral Femoral Condyle	Calcaneal tuberosity via Achilles' Tendon	Tibial n. S1 - S2	TCJ: PF Knee: Flexion
Plantaris	Lateral epicondyle of Femur	Calcaneal tuberosity	Tibial n. S1 - S2	Knee: *negligble* Flexion TCJ: PF Proprioception: Organ of proprioception for the plantarflexors
Soleus	Posterior Fibula Posterior Tibia	Calcaneal tuberosity via Achilles' Tendon	Tibial n. S1 - S2	TCJ: PF Lower leg: Stabilization

Deep Flexors

Table 2: Deep Flexors of the Posterior Lower Leg

Muscle	Origin	Insertion	Innervation	Action
Flexor digitorum longus	Middle 1/3 of posterior surface of Tibia	Bases of 2-5 Distal Phalanges	Tibial n. L5 - S2	TCJ: PF STJ: Inversion 2nd-5th Toe: MTP Flexion, PIP Flexion, DIP Flexion
Flexor hallucis longus	Posterior distal 2/3 of Fibula IO membrane	Base of 1st Distal Phalanx	Tibial n. L5 - S2	TCJ: PF STJ: Inversion 1st Toe: MTP Flexion, IP Flexion
Popliteus	Lateral Femoral Condyle Posterior horn of Lateral Meniscus	Posterior surface of Tibia	Tibial n. L4 - S1	Knee: Flexion, Unlocks the knee via femoral ER
Tibialis posterior	IO membrane Adjacent Tibia Adjacent Fibula	Cuneiforms 2-4 MT bases	Tibial n. L4 - L5	Knee: *negligble* Flexion TCJ: PF Arch support: Transverse arch, Longitudinal arch

References

1.

Gilroy AM, MacPherson BR, Wikenheiser JC, Voll MM, Wesker K, Schünke M, eds. Atlas of Anatomy. 4th ed. Thieme; 2020.