Ulnar Collateral Ligament

Ulnar Collateral Ligament (Medical Collateral Ligament) of the Elbow

  • The ulnar collateral ligament (or UCL) is an important elbow stabilizer
  • Anterior band tightens as elbow is in extension and posterior band tightens with flexion
  • For baseball players (pitchers), the late cocking and acceleration phase of pitching is the trouble spot
    • high level pitchers can hyper externally rotate
ulnar collateral ligament ucl tommy john pitcher mcl elbow baseball

Anterior and Posterior Bands of the UCL

  • The kinetic chain is important
    • Example: Jay “Dizzy” Dean
      • strikeouts were awesome until he broke his toe in the 1937 all star game
      • He had to change his pitching mechanics
      • never enjoyed similar success for the rest of his career
ulnar collateral ligament ucl tommy john pitcher mcl elbow baseball   ulnar collateral ligament ucl tommy john pitcher mcl elbow baseball

From: Sakiko Oyama, Baseball pitching kinematics, joint loads, and injury prevention, Journal of Sport and Health Science, Volume 1, Issue 2, September 2012

  • Physical Exam of suspected elbow injury
    • start from bottom and move your way up
    • foot/ankle/knee/hip
      • single leg squat
    • core
    • shoulder (ex. GIRD)
    • Elbow
      • ROM (remember terminal loss of ext is expected)
      • varus/valgus instability at 30
      • milking
        • kind of a stable moving valgus test
      • moving valgus stress test
        • maximum pain is at elbow extension from 120 to 70 of flexion (start in full flexion)
        • mimics arm movement
        • arm in abduction and external rotation – grab thumb and push their elbow with the back of your elbow (standing behind them)
    • Ulnar n.
      • paresthesias
      • wasting of first dorsal interossei
      • subluxation with flexion
    • Shoulder
      • stabilize scapula
        • can place patient supine or place thumb on the coracoid to stabilize it
      • also examine normal arc of motion because in real life scapula is not stabilized
    • X-rays
      • valgus stress x-ray
        • could see some opening medially (although very slight) or you can see some enthesiophytes etc medially in older patients/chronic problems
    • Ultrasound
      • dynamic ultrasound
    • MRI
      • arthrogram probably better, may be able to get away with regular MR in full thickness tear
      • although we focus on the tension side (medial), also look at the compression side
    • Treatment
      • Need to assess tear characteristics as well as demands (sport, level of competition, position, thrower vs. non-thrower, in season vs. out of season)
        • gymnasts are often overlooked, but they usually need to be fixed most of the time, similar to throwers, depending on where they are in their career
        • they walk on their elbows
      • Nonoperative Treatment
        • Biologics
          • lower grade, partial tears may do well with PRP (platelet rich plasma), etc
        • Bracing
        • Very little data
          • Rettig et al
            • 31 athletes
            • UCL insufficiency
            • no difference between complete and partial tears
            • 42% able to return to sports
          • Retrospective Review by Ford et al.
            • 43 injuries
            • all grade 3 treated operatively
            • non operatively treated tears did fairly well
      • Operative Treatment
        • Reconstruction
          • palmaris longus
        • Repair humeral sided avulsion and internal brace
          • best in acute cases with robust ligament
          • be careful not to overtighten in this case
          • maybe better for non-throwers as well
        • Literature
          • Savoie et al. AJSM 2008
            • good results with repair
          • Reconstruction with good results in 80+ % of patients
          • Mean Return-to-Play (RTP) in MLB is 16.8 months (Makhni et al)
        • Complication rate 18.6%, probably lower now
        • Endobutton and docking technique probably best for “load to failure”