Anatomy 2 Muscle groups of the Lower Limb
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Status: v103 Time: 2025-04-02 Tags: lecturenotes MSK Anatomy Links: The Lower Limb
tasks:
Content:
flashcarding directives muscles of the lower leg action of the muscles of the lower leg compartments of the lower leg origins and insertions of the muscles of the lower leg locations of the muscles of the lower leg
Objectives:
Understand the organisation of fascia and compartments of the thigh and leg discuss the muscles acting on the lower limb joints and their functions
- hip joint
- knee Joint
- ankle joint
- subtalar joint
- interphalangeal joints Understand the organisation of these muscles in the associated compartments
Rambles: Tissue layers
- Skin
- Superficial fascia
- Deep fascia
- Muscle
- Bone
Fascia is like silverskin Deep fascia decreases friction aids venous return and forms the intermuscular septa for compartments
Compartments of the thigh and leg
the fascia lata surrounds the whole thigh like a stocking
thigh:
thigh deep fascia is called fascia lata Anterior posterior and medial compartments
anterior is divided from the medial and posterior via the lateral and medial intermuscular septa
the posterior is divided from the medial via the posterior intermuscular fascia
lateral fascia lata is thickened into the iliotibial band certain muscles attach
Anterior muscles
Posterior muscles
Medial muscles
Leg
the crural fascia surrounds the leg like a stocking
the leg has anterior lateral and posterior compartments most of the space is taken up by the posterior. the interosseous membrane separates the anterior and posterior compartments and the anterior and posterior intermuscular septa separate the lateral compartment from the other 2
the leg also has the retinaculum (pleural retinacula) which is a thickening of the deep fascia which surrounds the leg like a stocking
the retinacula are:
- extensor retinaculum (dorsiflexive)?
- superior
- inferior
- fibular retinaculum (eversive?)
- superior
- inferior
- flexor retinaculum (plantarflexive)?
these act to stabilise the position of the tendons and allow smooth gliding of the tendons
Muscles of the hip joint:
Flexion:
Psoas major Origin: T12-L5 vertebra Insertion: Lesser Trochanter Iliacus Origin: Iliac fossa Insertion: lesser trochanter
Psoas minor (if present) Origin: Insertion:
Rectus femoris
Pectineus
Sartorius
Tensor fascia latae
Extension:
Gluteus maximus Origin: Gluteal surface of the ilium Insertion: Iliotibial tract and the gluteal tuberosity
multijoint: Semitendinosus Semimembranosus Biceps femoris
- long and short head
Adduction:
Pectineus Adductor brevis Adductor longus Adduction magnus adductor hiatus Gracilis
Abduction:
Gluteus Medius Origin: posterior iliac ridge (gluteal surface) Insertion: greater trochanter Gluteus minimus Origin:gluteal surface Insertion: greater trochanter gluteus minimus and medius prevents hip drop when walking. trendelbergs sign is over compensation with spine to walk
rotation:
Internal rotation (turning your palms inward from an anatomical position) gluteus medius and minimus assisted by most adductors and the TFL(very minimally)
External rotation Piriformis Gemellus superior Obturator internus Gemellus inferior
Obturator externus quadratus femoris
Muscles of the knee joint:
Flexion: (posterior compartment)
semimembranosus semitendonosus biceps femoris
sartorius is in the anterior compartment but also flexes knee
Extension: (Anterior compartment/ thigh group)
Rectus Femoris (also flexion of the hip) vastus Medialis vastus Intermedius vastus Lateralis
Rotation:
Medial rotation: Semitendinosus Semimembranosus
Lateral rotation: Biceps femoris
Muscles of the ankle complex:
Dorsiflexion: (Anterior compartment)
tibialis anterior tibial tuberosity to inferior medial cuneiform and metatarsal I extensor hallucis longus extensor digitorum longus
Plantarflexion: posterior compartment
gastrocnemius soleus plantaris (if present) Tibialis posterior flexor digitorum longus flexor hallucis longus
Eversion: lateral compartment
fibularis/peroneus longus and brevis
Inversion: these two are in both anterior and posterior compartment
tibialis anterior tibialis posterior