Lower Limb Joint Movements

Movements of the Lower Limb Joints

• Muscles facilitate bone movement around joints.
• The explanation will cover movements from the hip down to the foot.

Hip Joint Movements

• Flexion: Bringing the knee up towards the chest.
• Extension: Moving the leg behind you.
• Abduction: Moving the leg away from the midline.
• Adduction: Bringing the leg back to the midline.
• Medial/Internal Rotation: Rotating the femur inward.
• Lateral/External Rotation: Rotating the femur outward, with a greater range of motion.

Knee Joint Movements

• The knee acts as a hinge joint.
• Flexion: Bending the knee.
• Extension: Straightening the knee, reaching a locked position.

Ankle Joint Movements

• Dorsiflexion: Lifting the dorsum (top) of the foot towards the shin.
• Plantar Flexion: Pushing the plantar surface (sole) of the foot down, like standing on tiptoes.
• Inversion: Twisting the foot so the sole faces inward (medially).
• Eversion: Twisting the foot so the sole faces outward.
• Inversion has a greater range of motion than eversion.
• These movements aren't solely at the ankle joint; they involve sliding of multiple bones in the foot.

Muscles of the Hip

• Psoas Major: A muscle from the low back, a primary hip flexor.
• Iliacus: Attaches to the ilium and also contributes to hip flexion.
• Any muscle crossing the hip joint can act upon it.
• Quadriceps Femoris: A large muscle with four heads; one part, rectus femoris, crosses the hip and aids in hip flexion.
• Sartorius: The Tailor's muscle, crosses both the hip and knee joints, aiding in hip flexion, lateral rotation of the femur, and knee flexion.
• Gluteus Maximus: Large muscle, gives shape to the butt.
• Inserts into the femur and the iliotibial band.
• Contributes to power of hip extension.
• Hamstrings: Three muscles that cross the hip and knee joints.
• They extend the femur at the hip.
• Gluteus Medius and Minimus: Located laterally, these abduct the lower limb away from the midline.
• Stabilize hip during walking by keeping the pelvis level.
• Piriformis, Obturator (internus and externus), Gemellus (superior and inferior), and Quadratus Femoris: Six muscles that laterally rotate the hip.
• Tensor Fasciae Latae: Muscle pulling on the fascia lata, contributing to knee stability via the iliotibial tract.

Thigh Muscles

• Adductors: Located in the medial thigh, these muscles bring the lower limb back towards the midline.
• Help balance the trunk over the leg during walking/running.
• Gracilis: Most superficial adductor muscle.
• Adductor Longus, Brevis, and Magnus, along with Pectineus, comprise the adductor group.

Knee Muscles

• Quadriceps Femoris: Four parts converge at the patella, insert into the tibia, and extend the knee joint.
• Hamstrings: Located posteriorly, these flex the knee joint.
• Biceps Femoris: Located laterally, with two heads, one crossing the hip.
• Semitendinosus and Semimembranosus: Located medially, these two work together.

Calf Muscles

• Gastrocnemius and Soleus make up the bulk of the calf muscle.
• Allows lifting of the body weight, important in locomotion.
• Soleus: Does most of the work during walking and running.
• Gastrocnemius: Larger muscle belly lying over the soleus.
• Plantaris: A small muscle also contributing.
• All 3 merge into the Achilles tendon, inserting into the calcaneus (heel bone).
• Provides Leverage for plantar flexion.
• Popliteus: A deeper muscle which helps with knee joint stability and unlocking the joint for flexion.

Lower Leg and Ankle Muscles

• Flexor Hallucis Longus: Flexes the big toe (hallux) and is important for stability during standing, walking, and running.
• Flexor Digitorum Longus: Flexes all other toes.
• Tibialis Posterior: Runs around the ankle on the medial side and helps invert the foot, which is important for balance on uneven surfaces.
• Tibialis Anterior: Located on the anterior side of the tibia (shin bone), involved in dorsiflexion.
• Extensor Hallucis Longus: Extends the big toe.
• Extensor Digitorum Longus: Extends the other toes.
• Fibularis (Peroneal) Muscles: Located laterally.
• Includes fibularis longus and brevis, cause eversion of the foot.
• Peroneal muscles is another name for fibularis muscles.

Foot Muscles

• Many muscles in the foot, similar in complexity to those in the hand.
• Extensor Digitorum Brevis: Intrinsic muscles in the foot for toe extension.
• Extensor Hallucis Brevis: Short extensor for the big toe.
• Flexor Hallucis Brevis: Flexor for the big toe.
• Abductor Hallucis & Adductor Hallucis: Abduct and adduct the big toe, respectively.
• Interosseous Muscles: Abduct and adduct the toes.
• Lumbricals: Muscles with complex and difficult to describe movements.