Structural points:
A. There is a turning point on the lateral pelvis above the femur, which protrudes to the body side and is called the greater trochanter. Although the greater trochanter bone protrudes, it is due to a concave fossa on the pelvic side, which is called the greater trochanter fossa. This is because the structure is surrounded by developed muscle tissues such as gluteus maximus, gluteus medius, tensor fascia lata and ossicular lateral muscle.
B There are bone points such as lateral femoral condyle, medial tibial condyle, lateral tibial condyle, patella, tibial eminence and fibula around the knee joint.
The medial condyle of C-foot joint is the lower head of tibia and the lateral condyle is the lower head of fibula. The medial malleolus at the lower end of tibia is higher than the lateral malleolus at the lower end of fibula, forming the inclination angle of joint axis.
D the included angle between the long axis of femur and the force axis is 5-10, with an average of 6.
The force axis of the lower limb is consistent with the long axis of the lower limb and forms an angle of 3 with the vertical line of the center of gravity.
The angle between the long axis of femur and the plane line of knee joint is called femoral angle, which is about 75-80. Women are younger than men.
The angle between the plane line of the knee joint and the force axis of the lower limb (the long axis of the lower leg) is called the tibial angle, which is about 85-100, with an average of 93.
Leg muscles
Hip muscles (see trunk structure analysis)
thigh
1. anterior muscle group
Including rectus femoris, lateral femoris and intermediate femoris (below rectus femoris)-collectively referred to as quadriceps femoris.
Starting point: the lower side of the anterior spinous process of ilium, near the greater trochanter of femur.
Stop point: the common knee tendon stops at the tibial eminence.
Function: Lift the thigh to the lower part of the trunk and extend the calf (corresponding to triceps brachii).
Structural points:
A. Looking at the three muscles of the thigh from the side, the rectus femoris is the highest in about two-thirds of the thigh from bottom to top, and gradually becomes a tendon from bottom to top. Looks like it's inserted between the medial thigh muscle and the lateral thigh muscle.
B. From the front of the thigh, the outer thigh muscle and the inner thigh muscle make the inner and outer thighs plump and round. The external high point of lateral femoral muscle and lateral femoral muscle is about 1/2 strands. The outer high points of the inner thigh and the inner thigh muscles are under the thigh and close to the knee joint.
2. Sartorius muscle
Starting point: anterior spinous process of ilium.
Stop point: inside of tibial eminence.
Function: Hip valgus, lift thigh to the front of trunk.
Structural points:
A. The sartorius muscle is not a straight line from the starting point to the stopping point, but turns to the inner thigh.
B. The sartorius muscle divides the thigh obliquely into two pieces, one is the main piece of the thigh: the lower lateral piece; One is the secondary muscle group of the thigh: the upper medial muscle group (the upper body muscle group includes iliopsoas, pubis, adductor longus and gracilis, but they are all inserted under the sartorius muscle on the inner leg, and only one muscle group can be seen on the body surface). From the cross section of thigh, we can see the function of sartorius muscle between these two bodies.
3. Muscles at the back of thigh
Include gracilis, adductor, semimembranous, semitendinosus and biceps femoris.
Starting point: near the hip ischial tubercle (the upper part is inserted under the gluteal muscle).
Stop point: fibula capitulum, lateral upper end of tibia.
Function: The thigh is raised backward toward the trunk, the calf is raised backward, and the calf rotates inside and outside (corresponding to biceps brachii).
Structural points:
A. The upper part of the musculus dorsi femoris group is thick muscle tissue, and the lower part gradually becomes fine tendon, and after separation, it stops at the fibula capitulum and the outer end of tibia, which is similar to triceps brachii. In appearance, it forms a downward arc step between the upper muscle tissue and the lower tendon tissue.
There is an inconspicuous groove between the semitendinosus and the biceps femoris.
C. A deep triangular groove is formed between the two tendons at the lower part of the dorsum femoris muscle group, and the gastrocnemius muscle is inserted into it, which is slightly higher than the frontal bone.
shank
1. gastrocnemius
Starting point: above the medial and lateral condyle of femur.
Stop point: stop at the sole of male tendon.
Function: Pull the calf to the back of thigh, and pull the foot surface down and perpendicular to the calf.
Structural points:
A. gastrocnemius is divided into two parts.
B. Viewed from the front of the calf, gastrocnemius forms a stretched arc on the inside and outside of the calf, in which the outer arc is smoother than the inner arc, and the protruding point of the outer arc of the calf is higher than the inner arc of the calf.
C. The upper end of gastrocnemius is thick muscle tissue at 2/3 of the calf, with a large lower part and a small upper part. The upper end is inserted into two tendons separated from the back muscles of thigh, forming a depression.
D. The tendon formed by gastrocnemius muscle above calcaneus is called Achilles tendon, which is hard and powerful and forms a prominent structure behind the foot.
2. tibialis anterior
Starting point: lateral condyle of tibia.
Stop point: the inside of the foot.
Function: external rotation foot surface, lifting foot surface.
Key points of structure: tibialis anterior is close to the outside of the tibial line, and it is the thickest at the bottom-up 2/3 of the tibia, where the tibialis anterior is higher than the tibial line, which makes the tibial line form an inward concave structure.
3. extensor digitorum longus
On the outside of tibialis anterior, a structural block is often formed on the body surface and tibialis anterior.
4. Fibula muscle: It consists of anterior fibula muscle and short fibula muscle.
Starting point: the fibular head, the point behind the fibular head.
Stop point: lateral tibia and ankle, lateral calcaneus, stop at the sole of foot.
Function: Lift the foot and lift the outside of the foot.
Structural points: The peroneal muscle is behind tibialis anterior and extensor digitorum longus. When a strong person exercises his calf, the separation of these two muscles is highlighted.
5. soleus muscle
Starting point: tibia of knee joint, posterior end of fibula and head of fibula.
Stop point: Achilles tendon flows into the bottom and stops at the sole of foot.
Function: rotate the foot surface and lift the foot.
Structural points:
Soleus muscle is named for its shape. It is inserted behind the fibula and tibia, under the gastrocnemius muscle and all the way to the inside of the calf. So from the front, it can be seen from the lower side of gastrocnemius muscle inside and outside the calf, and it has a greater effect on body shape at this time.
* The tibialis anterior, the extensor digitorum longus, the fibula and the soleus muscles on the front and lateral sides of the calf can be understood as a whole in structure, so it is often inappropriate to overemphasize them in performance.
Key points of leg structure
A. rhythm: human legs conform to various movement laws and corresponding visual laws. When people stand upright, many Z-shaped folds or S-shaped curves are formed from all angles.
Front: the axis of thigh, inclined from the upper rotor to the inner side of the lower knee; The axis of the knee is inclined from the inner side of the upper knee to the outer side of the lower knee; The axis of the calf inclines from the outside of the upper knee to the inside of the lower ankle.
Comparison of non-Z-shaped broken lines: the high points of the inner and outer edges of the front part connect the inner and outer ankles, and the height of the inner side is lower than that of the outer side; The external protruding points of gastrocnemius muscle are connected, with high external and low internal; The connection line between the internal and external bone points of the knee joint is high outside and low inside; The external protrusion point of the anterior thigh muscle group is connected with the internal protrusion point, which is higher outside and lower inside.
Side: the pelvic axis inclines from the front of the upper body to the rear of the lower body; The thigh axis inclines from the rear side of the upper body to the front side of the lower knee; The axis of the knee joint inclines from the front of the upper knee joint to the rear of the lower knee joint; The axis of the calf inclines from the back of the upper knee joint to the front of the lower foot surface.
Transverse line of lateral structure: the transverse line of ankle joint is high before and low after; The cross-sectional line of knee joint is low in front and high in back; The pelvic floor is connected with the cross section, which is high in the front and low in the back.
B. volume, the concept of cross section should be used to understand volume, so as to transform two-dimensional space into three-dimensional space.
The cross section of the upper and middle thighs is small in front and large in back. The high point in the front is the rectus femoris, and the wide part in the back is the musculus dorsalis femoris. The sartorius muscle divides the thigh into two parts and forms a valley between them. The cross section of the thigh gradually becomes a square with almost the same width before and after reaching the knee.