The serratus posterior superior is a muscle within the intermediate compartment of the back. It is thin and rectangular in shape, and is located deep to the rhomboid muscles in the upper back.
The serratus posterior superior originates from the lower part of the ligamentum nuchae and the cervical and thoracic spines, usually C7-T3. Fibers of the muscle run in an inferolateral direction, attaching to ribs 2-5.
The serratus posterior superior has three primary functions: elevate ribs 2-5, provide innervation from intercostal nerves T2-T5, and supply a blood supply from posterior intercostal arteries.
The anatomy of the serratus posterior superior is relatively simple and straightforward. It is located in the intermediate compartment in the back, deep to the rhomboid muscles.
The muscle fibers originate from the lower part of the ligamentum nuchae and the cervical and thoracic spines, usually C7-T3 and attach to ribs 2-5. The fibers run in an inferolateral direction.
The primary function of the serratus posterior superior is to elevate ribs 2-5. It facilitates the contraction of the rib muscles, which are responsible for lifting the ribs during inspiration. This helps to increase the capacity of the thoracic cavity, leading to an increase in lung volume.
In addition to elevating ribs 2-5, the serratus posterior superior also provides innervation from the intercostal nerves (T2-T5) and a blood supply from the posterior intercostal arteries.
The serratus posterior superior can become weakened and dysfunctional due to a variety of conditions, including trauma, nerve injury, and postural problems. As a result, it can lead to impaired respiration and rib dysfunction. Weakness of this muscle can also contribute to poor scapular movement and positioning, thereby impairing shoulder mobility.
When assessing a patient for a dysfunction of the serratus posterior superior, a healthcare provider must take into account the patient's history, physical examination, and laboratory tests. In particular, an electromyography (EMG) test can be used to detect any nerve damage. Imaging studies such as X-rays and MRIs may also be used to assess the muscle's structure and function.
Treatment for serratus posterior superior dysfunction typically involves physiotherapy exercises to strengthen the weakened muscle. These exercises involve stretching the muscle and improving flexibility, as well as improving posture and scapular positioning. In some cases, bracing or taping may be necessary to improve stability.
The serratus posterior superior is a muscle located in the intermediate compartment of the back. Its primary function is to elevate ribs 2-5, and it also provides innervation from the intercostal nerves and blood supply from the posterior intercostal arteries. Weakness of this muscle can lead to impairments in respiration and shoulder mobility. A patient may require physiotherapy exercises as well as a variety of diagnostic tests in order to properly assess and treat serratus posterior superior dysfunction.
