• >30° radial instability indicates complete ligamentous injury and generally requires surgery.
  • Compare laxity to the uninjured side.
  • Stable bony UCL avulsion injuries heal well with immobilization.
  • A Stener Lesion occurs when the UCL tendon tears and then flips over the aponeurosis of the adductor pollicis muscle. This disrupts the ability of the tendon to heal without surgery.