The interspinales are a set of deep muscles in the back, usually absent from the thoracic region. These muscles originate from the spinous process of the cervical and lumbar vertebrae.
The fibers ascend and attach to the spinous processes of the vertebrae above, contributing to extension and rotation of the vertebral column, while also stabilizing the vertebrae. The posterior rami of the spinal nerves innervate these muscles, and they receive blood supply from the vertebral, deep cervical, occipital, transverse cervical, and lumbar arteries.
Fig 1 – The lumbar interspinales muscles. The cervical group has a similar arrangement.
The interspinales muscles offer several important functions, including facilitating spinal motion, providing postural support and stability, and transmitting mechanical forces from the upper body to the lower body and vice versa. Thus, they help to maintain proper body alignment and prevent back injuries and pain.
In addition, they are involved in preventing excessive flexion, extension, and rotation of the spine. They also participate in the coordination of trunk movements during physical activity such as running, jumping, and throwing.
The interspinales muscles can be affected by a variety of conditions, which can lead to severe pain and disability. These conditions include infections, muscle strains, and spondylosis. Muscle strains can be caused by factors such as repetitive motions, poor posture, and inadequate stretching.
Infections in the interspinales muscles are usually caused by bacteria, viruses, fungi, or parasites, and can lead to fever, pain, and swelling. Spondylosis, a degenerative spinal condition, is caused by the breakdown of the intervertebral discs.
The main symptoms of interspinales muscle problems include back pain, tenderness, tightness, difficulty moving, and reduced range of motion. Treatment depends on the cause and may include rest, physical therapy, medications, and injections. In severe cases, surgery may be necessary.
In summary, the interspinales muscles are a set of deep back muscles, which provide important functions such as facilitating spinal motion, providing postural support and stability, and transmitting mechanical forces from the upper body to the lower body and vice versa. They can be affected by a variety of conditions, which can cause severe pain and disability, and require appropriate treatment.
