Lower Limb Anatomy Notes

Lower Limb Anatomy Notes

General Overview

• Instructor: Dr. Tina Chiarelli
• Institution: University of Central Florida, College of Medicine

Palpable Landmarks of the Lower Limb

• Anterior Superior Iliac Spine
• Inguinal Ligament
• Tibial Tuberosity
• Tensor Fascia Lata
• Pectineus
• Adductor Longus
• Rectus Femoris
• Vastus Medialis
• Vastus Lateralis
• Gastrocnemius
• Tibia
• Fibularis Longus
• Tibialis Anterior
• Extensor Hallucis Longus
• Extensor Digitorum Tendons
  

Surface Anatomy Illustrations

• Figure A: Right limb surface anatomy.
• Figure B: Left limb musculature.
• Figure C: Left limb surface anatomy.

Bony Structures of the Pelvic Girdle

• Components:
    - Ilium
    - Pubis
    - Ischium
    - Sacrum
    - Coccyx
• Pelvic Girdle (Os Coxae or Hip Bone) includes:
    - Acetabulum
    - Pelvic Brim
    - Anterior Inferior Iliac Spine
    - Sacral Promontory
    - Iliac Fossa
    - Sacroiliac Joint
    - Pubic Arch

Ligaments of the Hip Joint

• Iliofemoral Ligament
• Ischifemoral Ligament
• Pubofemoral Ligament
• Capsular Ligament
• Labrum
• Transverse Acetabular Ligament
• Ligament of Head of Femur (Ligamentum Teres)

Arteries and Nerves of the Lower Limb

Arterial Supply to the Pelvis

• Aorta
• Common Iliac Artery
• Internal Iliac Artery
• External Iliac Artery
  

Venous Supply

• Veins of the Right Lower Limb and Pelvis:
    - Popliteal Vein
    - Small Saphenous Vein
    - Fibular Vein
    - Anterior Tibial Vein
    - Dorsalis Pedis Vein
    - Femoral Vein
    - Great Saphenous Vein

Lumbar Plexus and Sacral Plexus Nerves

Lumbosacral Plexus Overview

• Major Nerves:
    - Iliohypogastric Nerve (L1)
    - Ilioinguinal Nerve (L1)
    - Genitofemoral Nerve (L1-L2)
    - Obturator Nerve (L2-L4)
    - Femoral Nerve (L2-L4)
    - Lateral Femoral Cutaneous Nerve (L2-L3)
    - Sciatic Nerve

Musculature Innervation

1. Anterior Leg Muscles (e.g., Sartorius, Rectus Femoris) - Innervated by the Femoral Nerve.
2. Medial Thigh Muscles (e.g., Pectineus, Adductor Group) - Primarily Innervated by the Obturator Nerve.
3. Posterior Thigh Muscles (e.g., Hamstrings) - Innervated by the Tibial Branch of the Sciatic Nerve.
      - Common Fibular Nerve provides innervation to some lateral and anterior leg muscles.

Anterior Compartment Muscles of the Thigh

• Function:
    - Primarily Extensors at the Knee.
    - Flexors at the Hip (Sartorius, Rectus Femoris).
• Innervation:
    - Femoral Nerve
• Blood Supply:
    - Femoral Artery
• Muscles Include:
    1. Sartorius
    2. Rectus Femoris
    3. Vastus Group (lateralis, medialis, intermedius)

Medial Compartment Muscles of the Thigh

• Function:
    - Primarily Adductors at the Hip.
• Innervation:
    - Most are innervated by the Obturator Nerve.
• Muscle List Includes:
    1. Pectineus
    2. Adductor Longus
    3. Gracilis

Posterior Compartment Muscles of the Thigh (Hamstrings)

• Functional Roles:
    - Strong Flexors of the Knee.
    - Weak Extensors of the Hip.
• Included Muscles:
    - Biceps Femoris (long and short head)
    - Semitendinosus
    - Semimembranosus

Examining Pathologies of the Hip and Thigh

• Common Issues:
    - Angle of Inclination Affecting Gait.
    - Rickets and Osteomalacia due to Vitamin D/Calcium Deficiency.
    - Hip Fractures: Common in Osteoporosis—Fragility and Risk of Falls.

Ankle and Foot

Joint Structures

• Talocrural (Ankle) Joint
• Subtalar (Talocalcaneal) Joint

Common Ankle Fractures Symptoms

• Immediate Severe Pain
• Bruising and Swelling
• Inability to Bear Weight

Muscles of the Leg

Anterior Compartment

• Innervated by Deep Fibular Nerve
• Muscles include Tibialis Anterior, Extensor Hallucis Longus, Extensor Digitorum Longus.

Posterior Compartment

• Divided into Superficial and Deep Groups; all innervated by the Tibial Nerve.
• Blood Supply: Posterior Tibial Artery

Tendon Sheaths and Retinacula

• Synovial Sheaths provide protection for muscle tendons:
    - Flexor Retinaculum for Plantarflexor Tendons
    - Extensor Retinaculum for Dorsiflexor Tendons

Bones of the Foot

• Metatarsals, Cuneiforms, Navicular, Cuboid.
• Metatarsal Stress Fractures: Commonly occur in the 2nd and 3rd metatarsals due to repetitive forces.

Additional Anatomical Features

• Patella: A sesamoid bone crucial for knee stability and leverage.
• Major Ligaments of the Knee: Including Collateral Ligaments, Cruciate Ligaments, and Patellar Tendon.
• Proximal Leg Bones: Tibia and Fibula; critical for structural integrity and movement.

Conclusion

• Familiarity with the structures, muscles, ligaments, and common injuries affects the clinical understanding of lower limb anatomy, which is essential for diagnosis and treatment in medical practice.