Abdominal muscles are an important part of human connective tissue, including rectus abdominis, oblique abdominis, oblique abdominis and transverse abdominis. When they contract, they can bend and rotate the trunk to prevent the pelvis from leaning forward. Abdominal muscles also play an important role in the activity and stability of lumbar spine, and can also control the activity of pelvis and spine. Abdominal muscle weakness may lead to pelvic forward tilt and increase the physiological curvature of lumbar spine, increasing the chance of low back pain.
Anterolateral group
The anterolateral group constitutes the anterolateral wall of abdominal cavity, including external oblique muscle, internal oblique muscle, transverse abdominal muscle and rectus abdominis muscle.
obliquus externus abdominis
Located in the superficial layer of the ventral anterolateral wall muscle, it is platysma, with eight muscle teeth starting from the lateral side of the lower eight ribs and intersecting with the muscle teeth of serratus anterior and latissimus dorsi. The muscle bundle inclines from the outer upper side to the inner lower side, and the posterior lower muscle bundle stops in front of the iliac valley. The rest of the muscle bundles move inward to form aponeurosis, which passes through the front of rectus abdominis, participates in the front layer of rectus abdominis sheath, and finally reaches the white line of the abdominal midline. The lower edge of the aponeurosis of the external oblique abdomen is thickened and curled, connecting between the anterior superior iliac spine and the pubic tubercle, which is called inguinal ligament. There is a small bundle of tendon fibers at the inner end of inguinal ligament, which is called lacunar ligament, and the part of lacunar ligament extending and attaching to pubic comb is called pubic comb ligament (Cooper ligament). Inguinal ligament and pubic comb ligament are both important structures for strengthening inguinal canal wall in inguinal hernia repair. Above the pubic tubercle, the aponeurosis of the trapezius abdominis forms a triangular hole, which is the superficial (subcutaneous) ring of the inguinal canal.
obliquus internus abdominis
Located in the deep layer of the abdominal external oblique muscle. From thoracolumbar fascia, Iliac Valley and lateral inguinal ligament 1/2, the muscle bundle is fan-shaped, and the posterior muscle bundle rises almost vertically to the lower three ribs. Most of the muscle bundles extend to the aponeurosis, and the anterior and posterior layers wrap the rectus abdominis at the lateral edge, forming the anterior and posterior layers of the rectus abdominis sheath, and finally reaching the white line of the abdominal midline. The muscle bundle at the lower part of the internal oblique muscle goes forward and downward, crosses the front of the spermatic cord, continues to the aponeurosis, and merges with the aponeurosis of the transverse abdominis muscle to form the inguinal falx, or symphysis tendon, which ends at the inner end of the pubic comb and is close to the pubic tubercle. The lowest part of the internal oblique muscle is divided into some small and scattered muscle bundles, which are wrapped around the spermatic cord and testis together with the lowest part of the transverse abdominis muscle, and are called the cremaster muscle, which can support the testis when contracting.
transversus abdominis muscle
Located in the deep surface of the internal oblique muscle, it starts from the inner surface of the inferior six costal cartilage, the thoracolumbar fascia, the iliac crest and the outer side of the inguinal ligament, and the muscle bundle extends laterally forward to form aponeurosis, and passes through the back of the rectus abdominis to form the posterior layer of the rectus abdominis sheath, ending at the white line. The lowest muscle bundle of transverse abdominis muscle and the inner side of the lower edge of aponeurosis participate in the formation of cremaster and inguinal falx respectively.
Rectus abdominis
Located on both sides of the midline of the anterior abdominal wall, in the sheath of rectus abdominis, the upper part is wide and the lower part is narrow, starting from the pubic symphysis and pubic protuberance, and the muscle bundle ends in front of the sternal xiphoid process and the 5 th and 7 th costal cartilage. The whole length of the muscle is divided into several muscle ventrals by 3 or 4 transverse tendons. The tendon is closely combined with the anterior layer of rectus abdominis sheath, but the tendon behind rectus abdominis muscle is not obvious and does not heal with the posterior layer of rectus abdominis sheath, so the rectus abdominis muscle is free behind.
Rectus abdominis
The sheath covers rectus abdominis and is divided into two layers. The anterior layer consists of the anterior layer of the outer oblique aponeurosis and the anterior layer of the inner oblique aponeurosis, and the posterior layer consists of the posterior layer of the inner oblique aponeurosis and the transverse abdominis aponeurosis. At 4 and 5cm below the umbilicus, the aponeurosis of the posterior layer of rectus abdominis sheath completely transferred to the front of rectus abdominis sheath to form the anterior layer of sheath, which made the posterior layer missing. Therefore, the posterior layer of rectus abdominis sheath is interrupted by aponeurosis, forming an upward convex arc-shaped dividing line, which is called arch line or semicircle line.
white line
Located in the midline of the anterior abdominal wall, between the left and right rectus sheath, it consists of three layers of flat aponeurosis fibers on both sides. The upper part starts from xiphoid process and the lower part ends at pubic symphysis. The white line is tough and lacks blood vessels, and the upper part is wide, narrowing into a line from below the navel. At the midpoint of the white line, there is an umbilical ring, which is the weak point of the abdominal wall. If the abdominal organ bulges through this point, it is called umbilical hernia.
Hou qun
The latter group includes psoas major and quadratus lumborum, and psoas major will be described in lower limb muscles. Quadratulumburum, Quadratulumburum, is located in the posterior abdominal wall, on both sides of the spine, including psoas major, with erector spinae in the back. It starts at the back of iliac crest and ends at 12 rib and 1 4 lumbar transverse process, which is used to lower and fix 12 rib and make the spine scoliosis.
Extended data
canalis inguinalis
The inguinal canal is a fissure located between the platysma muscle and tendon of the anterolateral abdominal wall, located at the lower part of the anterolateral abdominal wall and above the medial half of the inguinal ligament, with a length of about 4-5cm, through which the spermatic cord of men or the round ligament of uterus of women passes.
The inguinal canal has two mouths and four walls. It is said that the deep (abdominal) ring of the inguinal canal is about 1 5cm above the midpoint of the inguinal ligament, with the transverse fascia of the abdomen protruding outwards and the inferior epigastric artery inside. The superficial (subcutaneous) ring of the external orifice, that is, the superficial inguinal ring, has aponeurosis of the external oblique muscle and the internal oblique muscle in the front wall, transverse fascia and inguinal falx in the rear wall, arcuate lower edges of the internal oblique muscle and transverse abdominal muscle in the upper wall and inguinal ligament in the lower wall. Inguinal canal is the weak area of abdominal wall and the prone site of hernia.
Inguinal triangle
The inguinal triangle is a triangle surrounded by the lateral edge of rectus abdominis, inguinal ligament and inferior epigastric artery, which is located in the lower part of the anterior abdominal wall.
Abdominal fascia
Abdominal fascia includes superficial fascia, deep fascia and intra-abdominal fascia.
1, the superficial fascia is one layer in the upper abdomen, and it is divided into shallow and deep layers below the navel. The superficial layer contains fat, called the deep layer of Kanpa fascia, and contains elastic fibers, called Scappa fascia, which continue downward with the fascia lata of thigh and inward downward with the superficial fascia of perineum and scrotum.
2. The deep fascia can be divided into several layers, covering the superficial and deep layers of the muscles of the anterolateral group respectively.
3. Intra-abdominal fascia is attached to the inner surface of abdominal cavity walls. Most of the fascia names are the same as the covered muscles, such as subphrenic fascia, lumbar fascia, iliopsoas fascia, pelvic fascia and transverse fascia.
reference data
Abdominal muscles-Baidu encyclopedia