Ulnar Collateral Ligament Injury Flashcards Preview

724: Medical Lectures > Ulnar Collateral Ligament Injury > Flashcards

Flashcards in Ulnar Collateral Ligament Injury Deck (16)

Thumb injuries are ___ in frequency only to knee injuries among skiers



What is usual mechanism for ulnar collateral ligament (UCL) injury?

Forced abduction and hyperextension of the metacarpophalangeal (MCP) joint


How do skiers develop skier's thumb?

When they fall the ski pole becomes fixed in the ground and the momentum of the skier drives the thumb into the pole handle


What are the presenting complaints?

- pain over the MCP joint (early)
- several weeks to months after the injury, pain, weakness, or loss of stability are the usual complaints


What are the 4 diagnostic criteria for UCL injury?

- MCP joint tenderness is localized to the ulnar side of the joint
- Valgus stress testing reveals a loss of integrity of the UCL
- MCP unable to fully flex to 90 degrees
- The strength or holding power (pinch grip) of the thumb and first finger may be compromised


An increase in joint laxity of __ degrees with valgus stress testing is indicative of UCL injury



Why are plain radiographs required?

to rule out the presence of an avulsion fracture


What are the 3 standard imaging views?

- posteroanterior
- lateral
- oblique


If radiographs do not demonstrate suspected laxity what can be performed?

ultrasonographic or fluoroscopic imaging while applying stress to the MCP joint


What imaging technique has a high sensitivity and specificity for ligament rupture



What is diagnosis of UCL injury based on?

A history of thumb injury involving forced abduction, combined with suggestive examination findings, such as local signs of inflammation and laxity of the MCP joint of the thumb with valgus stress


When is surgical intervention required?

- for patients who have a bony fragment on radiograph that is more than 2 mm displaced or involves greater than 10 to 20 percent of the articular surface
- for patients who manifest clinical signs of a complete UCL tear (valgus testing reveals more than 30 degrees of laxity, or laxity 15 to 20 degrees greater than the uninjured thumb)


What is the condition called when the aponeurosis of the adductor pollicis becomes trapped between the ends of the torn UCL?

a “Stener lesion”


When is nonsurgical management suggested?

- patients with normal radiograph or those showing bony fragments that are less than 2 mm displaced
- patients with minimal joint laxity with stress examination


What does nonsurgical treatment involve?

- ice applied to the MCP
- splinting with the MCP fixed to about 20 degrees


How long must the thumb remain completely rested and protected following injury?

3 weeks