Commonly injured structures in Wrist: Orthopedics

Commonly injured structures in Wrist: Orthopedics

The scapholunate ligament is the most commonly injured ligament in the wrist, usually the result of a fall on an outstretched hand. The scapholunate ligament is an intrinsic ligament binding the scaphoid and lunate together between the proximal and distal rows of carpal bones. Scapholunate dissociation is diagnosed radiographically with a widening of the scapholunate space greater than 3 mm. This is also known as the Terry Thomas sign. 

Injuries to the triquetrolunate ligament are less common, and usually result from a fall onto an outstretched and dorsiflexed hand. This injury may produce pain on the ulnar aspect of the wrist and can be confused with injury to the triangular fibrocartilage complex. 

The Space of Poirier refers to the area between the two palmar arches at the junction of the capitate and lunate, and is vulnerable to ligamentous disruption.

Laceration of Tendons: Orthopedics

Laceration of Tendons

Mallet finger is the injury resulting from laceration or rupture of the extensor tendon over Zone I, the distal phalanx, or distal interphalangeal joint. This injury causes the distal interphalangeal joint to be flexed at 40 degrees. It is the most common tendon injury in athletes.

Swan neck deformity may result from chronic untreated Mallet finger. 

Boutonniere deformity results from an injury in Zone III over the proximal interphalangeal joint. Injury of the central tendon and disruption of the lateral bands allow flexion as well as the flexor digitorum profundus to function unopposed. There is retraction of the extensor hood and resultant extension of the metacarpophalangeal and distal interphalangeal joints. Gamekeeper’s thumb is the rupture of the ulnar collateral ligament. This occurs as the result of radial deviation of the metacarpophalangeal joint.