Kyynelpintojen

Kyynelpintojen (elbow surfaces) is a Finnish term referring to the articular surfaces that form the elbow joint. The elbow comprises three articulations: humeroulnar, humeroradial, and proximal radioulnar joints. The main joint surfaces include the trochlea of the humerus articulating with the trochlear notch of the ulna, the capitulum of the humerus articulating with the head of the radius, and the radial head articulating with the ulna at the proximal radioulnar joint. These surfaces are covered by hyaline cartilage and enclosed by a fibrous joint capsule reinforced by ligaments, including the collateral ligaments and the annular ligament that stabilizes the proximal radioulnar joint.

Function and biomechanics: The elbow surfaces enable flexion and extension primarily through the humeroulnar articulation, while forearm rotation (pronation and supination) is achieved through the proximal radioulnar and radiocapitellar articulations. The joint surfaces are arranged to distribute load during lifting and pushing and to accommodate the range of motion required for daily activities.

Clinical relevance: Kyynelpintojen can be affected by traumatic injuries such as fractures of the distal humerus, olecranon, or radial head, as well as elbow dislocations. Degenerative conditions like osteoarthritis and inflammatory arthritides can alter the condition of the articular surfaces, leading to pain and stiffness.

Imaging and evaluation: Plain radiographs are typically first-line for suspected elbow injuries; CT provides detailed bone anatomy for complex fractures; MRI assesses soft tissues, cartilage, and ligaments around the joint. Understanding kyynelpintojen is fundamental to the evaluation and management of elbow pathology.