Tubercle of Assaki
Citation, DOI & article data
Tubercle of Assaki (also known as tubercle of Asskay 3) is a small bony protuberance of the central part of glenoid fossa with accompanying thinning of articular cartilage in this location 1.
It is presumably caused by constant pressure of the humeral head exerted on the inferior glenoid fossa 3. It is believed to be closely related to the glenoid bare spot, which is found in the same location. Some authors treat both these entities as practically identical 2.3.
It is a small (about 6 mm of average diameter 2) thickening of subchondral bone of the glenoid fossa, which is overlaid by the area of thinned cartilage known as glenoid bare spot 2.
Like the glenoid bare spot, it is best appreciated using fluid-sensitive sequences like T2 FSE in coronal and axial planes and it should not be mistaken for a cartilage defect 1.
History and etymology
The tubercle was first described by a French anatomist, Asskay 3.
- 1. Rudez J, Rudez ZM, Rudez. Normal anatomy, variants and pitfalls on shoulder MRI. (2008) European journal of radiology. doi:10.1016/j.ejrad.2008.02.028 - Pubmed
- 2. De WL, De BB, De AE, De SG, De VMG, De BE, De. About the variability of the shape of the glenoid cavity. (2004) Surgical and radiologic anatomy : SRA. doi:10.1007/s00276-003-0167-1 - Pubmed
- 3. Warner JJ, Bowen MK, Deng XH, Hannafin JA, Arnoczky SP, Warren RF. Articular contact patterns of the normal glenohumeral joint. J Shoulder Elbow Surg. 1998;7(4):381-388. doi:10.1016/s1058-2746(98)90027-1