Knee Anatomy: Ligaments and Muscles

• Ligaments connect bone to bone
• Tendons connect muscles to bone

Cruciate Ligaments

• Anterior Cruciate Ligament (ACL)
• Posterior Cruciate Ligament (PCL)

Collateral Ligaments

• Medial Collateral Ligament (MCL)
• Lateral Collateral Ligament (LCL)

Knee/Thigh Muscles

• Muscles of the medial knee/thigh adduct the thigh

Adductor Muscles

• Adductor Magnus originates at the ischial tuberosity, inserts from top to bottom of the femur, adducts and flexes the hip
• Adductor Longus acts only on the femur, inserts on the linea aspera of the femur, adducts and laterally rotates the hip
• Adductor Brevis originates at the inferior ramus of the pubis, inserts on the linea aspera of the femur, abducts and flexes the hip

Anterior Knee/Thigh Muscles

• Quadriceps include the Rectus Femoris, Vastus Lateralis, Vastus Medialis, and Vastus Intermedius
• Rectus Femoris crosses both the hip and knee, originates at the anterior inferior iliac spine and the acetabulum of the os coxae, inserts on the tibial tuberosity via the patella and the patellar ligament, extends the knee and flexes the hip
• Vastus Lateralis originates at the greater trochanter and lateral lip of the linea aspera of the femur, inserts on the tibial tuberosity via the patella and the patellar ligament, extends the knee
• Vastus Medialis (oblique) originates at the medial lip of the linea aspera of the femur, inserts on the tibial tuberosity via the patella and the patellar ligament, extends the knee
• Vastus Intermedius originates at the anterior surface of the shaft of the femur, inserts on the tibial tuberosity via the patella and the patellar ligament, extends the knee

Posterior Knee/Thigh Muscles

• Hamstrings flex the knee and extend the hip
• Biceps Femoris originates at the ischial tuberosity (long head) and lateral lip of the linea aspera (short head), inserts on the lateral surface of the head of the fibula and the lateral condyle of the tibia, flexes the knee and externally rotates
• Semitendinosus originates at the ischial tuberosity, inserts on the medial surface of the proximal end of the tibia, flexes the knee and internally rotates.
• Semimembranosus, the most medial hamstring muscle, originates at the ischial tuberosity, inserts at the medial surface of the proximal end of the tibia, flexes the knee and internally rotates

Hip Muscles

• Psoas Major and Minor originate at the transverse processes and bodies of the last thoracic and all the lumbar vertebrae, insert on the lesser trochanter of the femur, flex the hip and the trunk of the femur
• Gluteus Maximus, Medius, and Minimus all insert onto the greater trochanter

Gluteal Muscles

• Gluteus Maximus originates at the posterior gluteal line of the ilium and the posterior surface of the sacrum and the coccyx, inserts on the gluteal tuberosity of the femur and the iliotibial band, extends and laterally rotates the hip
• Gluteus Medius originates at the outer surface of the ilium between the posterior and the anterior gluteal lines, inserts on the lateral surface of the greater trochanter of the femur, abducts and internally rotates the hip
• Gluteus Minimus (deepest) originates at the outer surface of the ilium between the anterior and the inferior gluteal lines, inserts on the anterior surface of the greater trochanter of the femur, abducts and internally rotates the hip

Regions of the Pelvis

• Innominate bone
• Ilium
• Ischium
• Pubis
• Ala
• Sacrum
• Coccyx
• Femur

Pelvic Landmarks

• Iliac crest
• Anterior superior iliac spine
• Anterior inferior iliac spine
• Posterior superior iliac spine
• Posterior inferior iliac spine
• Ischial body
• Ischial spine
• Ischial tuberosity
• Ischial ramus
• Acetabulum
• Body of pubis
• Inferior ramus of pubis
• Obturator foramen
• Greater sciatic notch
• Sacroiliac joint
• Pelvic surface of the sacrum
• Symphysis pubis
• Labrum

Overview of knee ligaments including cruciate and collateral ligaments, detailing their function in bone-to-bone connection. Exploration of thigh muscles, focusing on adductor muscles, and anterior muscles, including the quadriceps and their role in knee and hip movement.