There are 206 bones and approximately 500 muscles in the human body. Most of these are skeletal muscles, which attach from one bone to another bone. One end of the muscle, the origin, attaches to a more stationary bone, while the other end, the insertion, attaches to a more movable bone.
The hamstring muscles attach to the tibia, which is one of the lower leg bones. The popliteus and soleus, both muscles in the calf, also attach to the tibia. Some of the muscles that extend and flex the ankles and toes, such as the tibialis anterior, also attach to this bone.
The other bone in the lower leg is the fibula, to which the hamstring, soleus and peroneus muscles attach. Like the tibia, the fibula is also an attachment site for the muscles that flex and extend the foot.
The femur, the bone in the upper leg, is the attachment site for numerous muscles. The gastrocnemius, one of the calf muscles, attaches here, as do all of the glute muscles. Three of the four quadriceps muscles attach to various points on the femur as well. The adductor muscles, which assist in pulling the leg toward the midline of the body, attach to the femur. Numerous hip muscles attach here as well, including the iliacus, the psoas major and the deep hip rotators.
Many of the muscles that attach to the femur also attach to the pelvis, including the glutes, the adductors, the hamstrings and the deep hip rotators. The rectus femoris, a quadriceps muscle, attaches to the pelvis, as does the sartorius. All of the abdominal muscles, including the obliques and the rectus abdominis, also attach to the pelvis. On the back, both the quadratus lumborum and latissimus dorsi muscles attach to this bone.
Sixteen different muscles attach to the scapula. All four of the rotator cuff muscles attach there, as do the deltoids. Many upper back muscles, such as the trapezius, rhomboids and levator scapula, attach to this bone. The tricep and bicep muscles, which bend and extend the elbow, attach to the scapula on their upper end. Other muscles that attach to the scapula include the serratus anterior, pectoralis minor and teres major.
Many of the muscles that attach to the scapula also attach to the humerus, which is the bone in the upper arm. These include all four rotator cuff muscles, the deltoids, the teres major and the triceps. The pectoralis major also attaches to the humerus, as do many of the muscles of the lower arm such as the brachialis and the brachioradialis.
The biceps brachii, which flexes the elbow, attaches to the radius, one of the lower arm bones. Many of the muscles of the forearm, such as the brachioradialis and pronator teres, attach to the radius, as do some of the thumb muscles.
The thumb extensors attach to the ulna, which is also in the forearm. The flexor and brachialis muscles attach here as well.