Bones and Muscles of Thigh and Knee

Anterior thigh muscles

Muscles that flex the thigh at the hip and/or extend the leg at the knee

Iliacus

Flexes the thigh at the hip

Iliacus attachment

Hip bone to lesser trochanter

Psoas major

Flexes the thigh at the hip

Psoas major attachment

Vertebrae to lesser trochanter

Sartorius

Flexes the thigh at the hip and also flexes the leg at the knee

Sartorius attachment

Anterior superior iliac spine to tibia

Sartorius fact

Longest muscle in the body

Quadriceps femoris

Extends the leg at the knee joint

Quadriceps femoris attachment

Attaches via quadriceps tendon, patella, and patellar ligament

Four quadriceps muscles

Rectus femoris, vastus lateralis, vastus intermedius, vastus medialis

Rectus femoris

One of the four quadriceps femoris muscles

Vastus lateralis

Lateral quadriceps muscle

Vastus intermedius

Quadriceps muscle located behind rectus femoris

Vastus medialis

Medial quadriceps muscle

Medial thigh muscles

Adduct and flex the thigh

Adductors

Adductor longus, adductor brevis, and adductor magnus

Adductor longus

Medial thigh muscle that adducts and flexes the thigh

Adductor brevis

Medial thigh muscle that adducts and flexes the thigh

Adductor magnus

Medial thigh muscle that adducts and flexes the thigh

Pectineus

Medial thigh muscle that adducts and flexes the thigh

Gracilis

Adducts/flexes the thigh and also flexes the leg at the knee

Gracilis location

Travels along the medial thigh

Lateral thigh

Contains a single muscle that abducts the thigh at the hip

Tensor fasciae latae

Abducts the thigh and connects to the iliotibial tract

Iliotibial tract (IT band)

Band of connective tissue associated with tensor fasciae latae

Gluteal muscles

Posterior hip muscles

Gluteus maximus

Extends the thigh at the hip joint

Gluteus maximus example action

Used when getting out of a chair to stand

Gluteus medius

Abducts the thigh

Gluteus minimus

Abducts the thigh

Gluteus maximus depth

Most superficial of the three gluteal muscles

Gluteus minimus depth

Deepest of the three gluteal muscles

Hamstrings

Posterior thigh muscles that extend the thigh and flex the leg

Hamstring hip action

Extend the thigh at the hip joint

Hamstring knee action

Flex the leg at the knee joint

Three hamstring muscles

Biceps femoris, semitendinosus, semimembranosus

Biceps femoris

Laterally located hamstring muscle

Semitendinosus

Hamstring muscle

Semimembranosus

Hamstring muscle

Hamstring common attachment

Group has similar attachment from ischial tuberosity toward the leg

Knee joint classification

Synovial hinge joint; diarthrosis

Bones associated with knee

Femur, tibia, and patella

Fibula and knee joint

Fibula does not articulate with the femur

Patella location

Embedded in the quadriceps femoris muscle tendon

Quadriceps tendon

Connects quadriceps femoris toward the patella

Patellar ligament

Continuation from patella to tibia

Patellar ligament attachment

Attaches to the tibial tuberosity

Knee collateral ligaments

Provide stabilization and support to the knee

Fibular collateral ligament

Prevents hyperadduction of the leg

Fibular collateral ligament function

Prevents leg from shifting too far medially from the femur

Tibial collateral ligament

Prevents hyperabduction of the leg

Tibial collateral ligament function

Prevents leg from shifting too far laterally from the femur

Cruciate ligaments

Knee ligaments that cross, forming an X

Anterior cruciate ligament (ACL)

Prevents hyperextension of the knee joint

ACL additional function

Prevents tibia from moving too far anteriorly relative to femur

Posterior cruciate ligament (PCL)

Prevents hyperflexion of the knee joint

PCL additional function

Prevents tibia from shifting posteriorly relative to femur

Menisci

Medial and lateral C-shaped fibrocartilage pads within the knee joint

Medial meniscus

C-shaped fibrocartilage pad on medial side of knee

Lateral meniscus

C-shaped fibrocartilage pad on lateral side of knee

Menisci function

Stabilize and cushion the knee joint

Other example of fibrocartilage

Intervertebral discs

ACL injury causes

Hyperextension and twisting movements

ACL rupture

A popping noise may occur when the ligament ruptures

Sports associated with ACL injuries

Sports involving twists, sudden stops, and changes in direction

Unhappy triad

Knee injury commonly caused by a lateral blow to the knee

Three structures of the unhappy triad

ACL, tibial collateral ligament, and medial meniscus

Unhappy triad — ACL

One of the three structures torn

Unhappy triad — tibial collateral ligament

One of the three structures torn

Unhappy triad — medial meniscus

One of the three structures torn

Anterior thigh general action

flex the thigh, extend the leg

Medial thigh general action

flex and adduct the thigh

Posterior thigh (hamstrings) general action

extend the thigh and/or flex the leg

Lateral Thigh general action

abduct the thigh

Name letter B

Sacrum

Name letter C

Coccyx

Name what top arrow is pointing to

Anterior superior iliac spine

Name what middle arrow is pointing to

Greater trochanter

Name what bottom arrow is pointing to

Lesser trochanter

Name yellow muscle

Sartorius

Name green muscle

Psoas major

Name blue muscle

Iliacus

Name blue muscle

Recuts Femoris

Name green muscle

Vastus Lateralis

Name purple muscle

Vastus medialis

Name purple muscle

Adductors

Name blue muscle

Pectineus

Name green muscle

Gracilis

Name yellow muscle

Tensor fasciae latae

Name green muscle

Gluteus Medius

Name blue muscle

Gluteus maximus

Name purple muscle

Gluteus Minimus

Name blue muscle

Biceps Femoris (laterally placed)

Name green muscle

Semitendinosus

Name yellow muscle

Semimembranosus

name blue outline

Quadriceps tendon

name green outline

Patellar ligament

Name blue label

Fibular collateral ligament

Name green label

Tibial collateral ligament