Ulnar Collateral Ligament Injury Flashcards
Thumb injuries are ___ in frequency only to knee injuries among skiers
second
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
30
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
MRI
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
