Flexor Tendon Injury at the DIP Joint

Aka: Flexor Tendon Injury at the DIP Joint, Jersey Finger, Flexor Digitorum Profundus Avulsion, FDP Tendon Injury, DIP Flexor Tendon Avulsion

1. Mechanism
   1. Ring finger most commonly affected (75% of cases)
      1. Protrudes further than other fingers on grasping
   2. Forced extension of actively flexed DIP joint
   3. Example
      1. Football player grabs a player's jersey on tackle
      2. Lifting latch on car door
2. Symptoms
   1. Pain and swelling at volar aspect of DIP
   2. Localized tenderness and fullness if tendon retraction
   3. Affected finger more extended at DIP when hand at rest
   4. Inability to flex at affected DIP joint
3. Signs
   1. Do not passively force finger into extension
      1. Avulsed tendon retracts with avascular risk
   2. Assess Profundus
      1. Hold proximal interphalangeal joint (PIP)
      2. Test active flexion of distal Interphalangeal joint
      3. Avulsion results in inability to flex at DIP
      4. FDP Tendon may retract to the palm
   3. Assess for flexor digitorum superficialis rupture
      1. Hold all fingers except affected finger in extension
      2. Test proximal interphalangeal joint (PIP) flexion
4. Radiology: XRay digit (AP, Lateral, Oblique)
   1. Assess for bony avulsion of volar distal phalanx
5. Management: Early surgical repair in all cases
   1. Temporize by Splinting finger in current position
   2. Hand surgeon or orthopedics referral
      1. Best recovery if repaired within 7-10 days of injury
6. Complications
   1. Fibrosis and scarring of tendon sheath
      1. Associated with delayed surgical repair
7. Follow-Up
   1. No sports participation until fully recovered
8. References
   1. Brandenburg (1996) Consultant p.331-340
   2. Calmbach (1996) Lecture in Minneapolis
   3. Dvorak (1996) Lecture in Minneapolis
   4. Lillegard (1996) Lecture in Minneapolis
   5. Wang (2001) Am Fam Physician 63(10):1961-66