What Muscles Flex The Hip?

Hip flexors allow you to sit up from a reclined position or raise your legs while lying in bed. These muscles also assist walking, climbing stairs and stepping onto a platform. Sitting for an extended period of time on a regular basis tightens your hip flexors, possibly leading to lower back pain and restricted mobility. Sit ups and leg raises can help stretch overactive flexors. Contact your physician for further information.

Psoas Major

The psoas major is the chief hip flexor. It originates on the transverse processes that stick out on the back and sides of the bony enclosure surrounding the spinal cord, running from T12 of the thoracic to L5 of the lumbar vertebrae. The psoas inserts at the lesser trochanter, or process, of the femur. In addition, the psoas externally rotates the hip, and extends and rotates the lumbar spine.

Iliacus

The iliacus works with the psoas. Together they form the iliopsoas muscle, the strongest of the hip flexors. The iliacus originates on the pelvic crest and inserts at the psoas major, capsule, or membrane, of the hip joint, and lesser trochanter of the femur.

Rectus Femoris

The rectus femoris originates from the ilium, the largest pelvic bone, and inserts at the tibial tuberosity, or protrusion, of the tibia at the knee. In addition to flexing the hip, this muscle extends the knee.

Sartorius

The sartorius originates at the front end of the iliac crest and inserts at the middle of the tibia at the knee. It is the longest muscle in the human body. The sartorius also externally rotates and abducts the hip, and flexes and internally rotates the knee.

Tensor Fascia Latae -- TFL

The TFL muscle originates from the iliac crest and inserts at the iliotibial band about a third of the way down the thigh. This muscle is also involved in hip abduction and internal rotation.

Adductors

The adductors involved in hip flexion are the longus, magnus-anterior fibers, and brevis. Both the adductors longus and brevis originate at the front of the inferior pubic ramus of the pelvis and insert at the femur. The adductor magnus-anterior originates at the ischial ramus of the pelvis and inserts at the femur. All three muscles also participate in hip adduction and internal rotation.

Gracilis

The gracilis originates at the front lower pubis and inserts at the middle of the tibia. This muscle also adducts and internally rotates the hip.

Pectineus

The pectineus originates at the superior pubic ramus of the pelvis and inserts at the back of the femur. This muscle also adducts and internally rotates the hip.