ulnar collateral ligament

noun

plural ulnar collateral ligaments

1

: a triangular ligament of the inner side of the elbow that connects the medial parts of the humerus with the ulna, helps to stabilize the elbow joint, and is often injured in sports (such as baseball) which involve repeated overhand throwing

… the preseason Atlantic Sun pitcher of the year, will miss the rest of the season after suffering ulnar collateral ligament damage on the inside of his throwing elbow.

—Dana Caldwell

called also UCL

2

: a ligament of the wrist on the little-finger side that connects the distal end of the ulna with bones in the wrist and helps to stabilize the wrist joint

Palpate to the end of the ulnar styloid, and notice the gap between it and the carpals. … With the wrist in radial deviation, the ulnar collateral ligament can be felt bridging this gap.

—Management of Common Musculoskeletal Disorders

called also UCL

3

: a ligament of the inner thumb that connects the two bones at the base of the thumb and helps to stabilize the thumb

… skier's thumb, an ulnar collateral ligament sprain or injury to the thumb usually resulting from a fall.

—Heidi Splete

called also UCL

Examples of ulnar collateral ligament in a Sentence

Recent Examples on the Web

Ohtani also made an impact on the mound for LA, making his return to pitching in June after an almost two-year layoff, following two procedures, including one to repair the right ulnar collateral ligament in his elbow and his left shoulder last offseason. —Jacob Lev, CNN Money, 14 Nov. 2025

Keegan Murray, the team’s best forward and one of its only reputable defenders, has yet to play a game after undergoing surgery to repair an ulnar collateral ligament tear in his left thumb. —Jason Anderson, Sacbee.com, 13 Nov. 2025

Garrett missed all of last season after undergoing revision surgery on the ulnar collateral ligament in his left elbow. —Barry Jackson, Miami Herald, 6 Nov. 2025

Shortly into his first season with Texas in 2023, DeGrom underwent the second Tommy John surgery of his career for a tear in his right ulnar collateral ligament. —Lawrence Dow, Fort Worth Star-Telegram, 29 Oct. 2025

Word History

First Known Use

1942, in the meaning defined at sense 1

Medical Definition

ulnar collateral ligament

noun

1

: a triangular ligament of the elbow that connects the medial epicondyle of the humerus with the medial edge of the coronoid process and the olecranon of the ulna, that helps to stabilize the elbow joint, and that is often injured in sports (as baseball) which involve repeated overhand throwing

… the preseason Atlantic Sun pitcher of the year, will miss the rest of the season after suffering ulnar collateral ligament damage on the inside of his throwing elbow.

—Dana Caldwell, The Naples (Florida) Daily News

… McDowell had a torn ulnar collateral ligament and will need Tommy John surgery to repair it …

—David Campbell, The Eagle (Bryan, Texas)

called also medial collateral ligament, UCL

compare radial collateral ligament sense 1

2

: a ligament of the wrist on the little finger side that connects the distal end of the ulna of the arm with the triquetral and pisiform bones and helps to stabilize the wrist joint

Palpate to the end of the ulnar styloid, and notice the gap between it and the carpals. … With the wrist in radial deviation, the ulnar collateral ligament can be felt bridging this gap.

—Management of Common Musculoskeletal Disorders: Physical Therapy Principles

called also UCL

compare radial collateral ligament sense 2

3

: a ligament of the inner middle joint of the thumb that connects the head of the metacarpal bone with the adjacent phalanx

… skier's thumb, an ulnar collateral ligament sprain or injury to the thumb usually resulting from a fall.

—Heidi Splete, Family Practice News

called also UCL

compare radial collateral ligament sense 3