McKee, "Fractures of
capitellum and trochlea," Orthopedic Clinics of North America, vol.
Oppenheim (16) described a peculiar case of concomitant fracture of the trochlea and
capitellum. He suggested that both these fractures occurred due to shear force transmission from the radial head and coronoid to the
capitellum and the trochlea respectively in extended position.
Roofeh, "Herbert screw fixation of a
capitellum fracture.
In the case of OCD, the loose body is usually located near the
capitellum and radial head; for fractures, near the site of injury; for synovial chondromatosis, loose bodies are frequently anterior.
The
capitellum contains thick hyaline cartilage anteriorly that articulates with the proximal radius.
While this might be sufficient for fixation of a simple
capitellum fracture, the coronal shear fracture requires a more extensile exposure of the anterior humeral articular surface.
(3) The radial head fractures are caused by a valgus force on the elbow as the head is driven into the
capitellum. Radial head fractures have been classified into four types according to Mason.
In order to determine the effects of two different headless screw designs on fixation of simulated
capitellum fractures six matched pairs of embalmed humeri had simulated
capitellum fractures created.
The mnemonic "CRITOE" (
Capitellum, Radial head, Internal (medial) epicondyle, Trochlea, Olecranon and External (lateral) epicondyle) can help diagnose certain fractures, particularly those where an ossification center 'appears' out of the expected order.
In addition, proximally, the radius abuts the
capitellum leading to elbow pain and decreased range of motion.
The chronological order of appearance of the elbow ossification centers follows this rule:
capitellum, radial head, medial epicondyle, trochlea, olecranon, and lateral epicondyle.
Combined shear fractures of the trochlea and
capitellum associated with the anterior fracture-dislocation of the elbow.