The quadrate ligament is a fibrous band in the forearm that connects the ulna to the radius.
It's more specifically defined as:
A fibrous band attached to the inferior border of the radial notch on the ulna and to the neck of the radius. The annular ligament strengthens its borders. Essentially, it's a connective tissue structure that plays a key role in radioulnar joint stability.
Key Features:
- Attachment Points: It originates from the inferior edge of the radial notch (a depression on the ulna where the head of the radius articulates) and inserts onto the neck of the radius.
- Strengthening: Fibers from the upper border of the annular ligament provide additional support to the quadrate ligament.
- Function: Primarily contributes to the stability of the proximal radioulnar joint, helping to prevent excessive rotation or separation of the radius and ulna. It also limits spin during supination and pronation.
In essence, the quadrate ligament is a critical stabilizer of the forearm, facilitating smooth and controlled rotation of the radius around the ulna.
