Muscle
Gracilis
Slender medial-thigh muscle reaching the tibia
High-yield
Unlike the main adductors that end on the femur, gracilis crosses both hip and knee. It can therefore bring the thigh inward and also help bend and internally rotate the flexed knee.
Overview
Gracilis descends superficially from the pubis and crosses the inner side of the knee. Its long tendon joins sartorius and semitendinosus at the pes anserinus on the proximal tibia.
Reference facts
- Origin
- Pubic body near the symphysis and adjacent inferior pubic ramus
- Insertion
- Proximal medial tibia as part of the pes anserinus tendon group
- Action
- Adducts the thigh; assists knee flexion and internal rotation of the leg when the knee is flexed
- Innervation
- Anterior branch of the obturator nerve, usually described with L2-L3 roots
- Blood supply
- Variable branches from medial circumflex femoral, profunda femoris, femoral, obturator and descending genicular arteries
Mnemonic
Follow the route across two joints: pubis to inner knee to tibia. Then link the shared tibial attachment to sartorius and semitendinosus.
Clinical correlation
The tendon is used in some knee ligament reconstructions, and a functioning muscle transfer may help restore movement elsewhere, including facial movement. Its anatomy and neurovascular supply guide the choice of reconstruction.
Frequently asked questions
What does the gracilis do?
Adducts the thigh; assists knee flexion and internal rotation of the leg when the knee is flexed.
What nerve innervates the gracilis?
Anterior branch of the obturator nerve, usually described with L2-L3 roots.
Where does the gracilis attach?
The gracilis originates from the pubic body near the symphysis and adjacent inferior pubic ramus and inserts on the proximal medial tibia as part of the pes anserinus tendon group.
What is the blood supply of the gracilis?
The gracilis is supplied by the variable branches from medial circumflex femoral, profunda femoris, femoral, obturator and descending genicular arteries.