Leg Anatomy: Muscles and Compartments

Which of the following muscles are found in the posterior compartment of the leg?

Which of the following muscles is not an intrinsic muscle of the foot?

Which of the following structures is not found in the popliteal fossa?

Which of the following muscles is an antagonist to the biceps brachii during elbow flexion?

Which of the following muscles is found in the lateral compartment of the leg?

Which of the following muscles forms the calcaneal tendon (Achilles tendon)?

Which of the following muscle groups is the antagonist to the quadriceps femoris during knee extension?

Which of the following is not a good site for intramuscular injections in adults?

Which of the following muscles is responsible for inversion of the foot?

Which of the following muscles is not part of the dorsal group of intrinsic foot muscles?

Muscles of the Lower Limb

Thigh Muscles

Anterior compartment: extensors of the knee muscles
- Quadriceps femoris (4 heads: rectus femoris, vastus medialis, vastus lateralis, vastus intermedius)
  - O.pelvis → In.tibial tuberosity via quadriceps tendon & patellar ligament
  - Extension of the knee (straight leg), stabilize patella, hip flexion
- Sartorius (longest muscle in the body)
  - O.ilium → In.medial tibia
  - Flex knee, flex hip + lat rotation
Medial compartment: adductor muscles
- Adductor longus, brevis, magnus
  - O.pelvis → In.prox femur
  - Aduction of thigh, med rotation, maintenance of posture
- Pectineus
- Gracilis

Leg Muscles

Anterior compartment: dorsi flexors of the foot & digits
- Tibialis anterior
  - O.lat tibia → In.medial foot
  - Dorsi flexion of foot, inversion of foot
- Extensor hallucis longus
- Extensor digitorum
- Peroneus/fibularis tertium
Lateral compartment: evertors of the foot
- Peroneus/fibularis longus
- Fibularis brevis
Posterior compartment: plantar flexors of the foot & digits
- Gastrocnemius (2 heads: med & lat)
  - O.med & lat epicondyle of femur → In.calcaneal tendon (Achilles tendon)
  - Plantar flexion of the foot, flexion of knee
- Soleus
  - O.prox tibia & head fibula → In.calcaneal tendon
  - Plantar flexion of the foot, flexion of knee

Gluteal Compartment

Piriformis
Gemellus inf/sup
Obturator intern/extern
Quadratus femoris

Intrinsic Muscles of the Foot

Dorsal group
- Extensor hallucis brevis
- Extensor digitorum brevis
Plantar group (4 layers: flexors of digits)
- Plantar Aponeurosis: Thickened fascia from calcaneus → 5 toes
  - Longitudinal arch support, protect nerves and vessels

This quiz covers the muscles and compartments of the leg, including the hamstrings, hip extension, knee flexion, and foot dorsiflexors. It also discusses the anterior and lateral compartments of the leg, along with the functions of specific muscles in each compartment.