The musculus obliquus internus abdominis, commonly known as the internal oblique muscle, is a deep muscle located in the abdominal region of the human body. Specifically, it is situated on the lateral sides of the abdomen, beneath the external oblique muscle and above the transversus abdominis muscle.
This muscle arises from the thoracolumbar fascia, which is a fibrous tissue layer located in the lower back. It also attaches to the iliac crest, which is the curved ridge of bone on the upper part of the hip bone. From these points of origin, the musculus obliquus internus abdominis extends forward and upward towards the ribcage.
The main function of this muscle is to support the abdominal wall and aid in core stability. It achieves this by helping in flexion and rotation of the trunk, bending the torso from side to side, and compressing the abdominal cavity.
The musculus obliquus internus abdominis receives its innervation from the thoracoabdominal nerves, which originate from the lower spinal cord segments. Additionally, its blood supply comes primarily from the superior and inferior epigastric arteries.
Understanding the musculus obliquus internus abdominis is crucial for medical professionals, fitness experts, and individuals seeking to strengthen their core muscles. Proper engagement and strengthening of the internal oblique muscle is essential for maintaining good posture, preventing lower back pain, and promoting overall abdominal strength and stability.
