Manubriosternal joint
Symphysis manubriosternalis
Definition
The manubriosternal joint is an articulation between the manubrium and the body of the sternum.
The manubriosternal joint is first a synchondrosis (bones are joined by fibrocartilage and the joint may be called manubriosternal synchondrosis), and later in life is classified as a symphysis, which is a type of cartilaginous joint where the bones are joined by fibrocartilage.
The joint undergoes age-related changes, including a reduction in thickness and hydration, loss of uniformity and arrangement of collagen fibers, hyalinization, and the presence of focal lesions, which are indicative of a degenerative process. The joint is relatively stable due to its fibrocartilaginous nature, which restricts ossification and fusion, making manubriosternal fusion a rare occurrence.
In terms of anatomical landmarks, the manubriosternal joint is located at the level of the second rib attachment and is often used as a reference point in thoracic imaging and surgical procedures.
References
1.Manubriosternal Joint: Synchondrosis or Symphysis? Analysis of Morphology and Aging in Humans.Sarcinelli JM, Eustáquio-Silva R, da Silva Baptista J.Surgical and Radiologic Anatomy : SRA. 2019;41(3):275-279. doi:10.1007/s00276-018-2154-6.
2.CT Anatomy of the Mediastinal Structures at the Level of the Manubriosternal Angle.Chukwuemeka A, Currie L, Ellis H.Clinical Anatomy (New York, N.Y.). 1997;10(6):405-8. doi:10.1002/(SICI)1098-2353(1997)10:6<405::AID-CA6>3.0.CO;2-N.
3.Postnatal Development of the Human Sternum.O'Neal ML, Dwornik JJ, Ganey TM, Ogden JA.Journal of Pediatric Orthopedics. 1998 May-Jun;18(3):398-405.
