Written and peer-reviewed by physicians—but use at your own risk. Read our disclaimer.

banner image


Trusted medical answers—in seconds.

Get access to 1,000+ medical articles with instant search
and clinical tools.

Try free for 5 days

Finger injuries

Last updated: September 18, 2020


Finger injuries are very common and because there are many different possible injuries, only some of the more common flexor and extensor tendon as well as ligament injuries will be covered here. Injury is typically caused by lacerations (work place injury, road traffic accidents) or blunt force (e.g., ball sports, falling). For instance, forced extension of the distal interphalangeal joint (DIP) can damage the flexor digitorum profundus (FDP) tendon and lead to a loss of DIP flexion (Jersey finger). Forced flexion of the DIP causes extensor digitorum (ED) tendon injury, which results in a loss of DIP extension (mallet finger). Rupture/slippage of the central band of the ED tendon is primarily due to laceration or blunt injury and results in a hyperextension of the DIP with flexion of the PIP (Boutonniere deformity). Sudden forced hyperextension and abduction of the metacarpophalangeal joint (MCP) of the thumb can tear the ulnar collateral ligament (UCL) and cause laxity (Gamekeeper's thumb). While all flexor tendon injuries need to be surgically repaired, most extensor tendon and some ligament injuries can be managed conservatively with splints. Complete laceration or no response to conservative therapy are indications for surgical repair. Postoperative complications of tendon or ligament injuries include adhesions, joint contractures, and chronic joint deformities (e.g., swan-neck deformity, chronic mallet finger). Early recognition and treatment of injuries and their complications is necessary to prevent permanent disability.



Differential diagnoses

Differential diagnoses of finger injuries

Affected tendon(s) or ligament(s) Condition Mechanism of injury Clinical features Treatment Possible complications
Flexor digitorum profundus tendon Jersey finger
  • Sudden hyperextension of a flexed DIP (forced extension)
  • Avulsion injury/rupture of the FDP tendon from its point of insertion
  • Pain, swelling of the DIP (palmar aspect)
  • Loss of DIP flexion → the affected finger does not flex when making a fist
  • Always surgical
    • Primary repair .
    • Tendon graft
Extensor digitorum tendon Mallet finger
  • Loss of extension of the DIP
  • Conservative: splint in extension position
  • Surgical repair for:
    • Displaced fracture
    • ≥ 45-degree extension deficit
Central band of extensor digitorum tendon Boutonniere deformity
  • Slippage/disruption of the central band of the ED

Ulnar collateral ligament (UCL) of the thumb

Gamekeeper's thumb (Skier's thumb)
  • Hyperextension and sudden forced abduction of the MCP of the thumb (e.g., falling on the thumb; skiing injury) → UCL tears
  • Conservative: Thumb spica (splinting)
  • Surgical repair: for persistent deformities (e.g.: repair of the torn UCL; MCP joint fusion)


The differential diagnoses listed here are not exhaustive.


  1. Clavero JA, Alomar X, Monill JM et al. MR Imaging of Ligament and Tendon Injuries of the Fingers. Radiographics. 2002; 22 (2): p.237–256.
  2. Jersey Finger. http://www.orthobullets.com/TopicView.aspx?id=6015. Updated: January 23, 2017. Accessed: January 23, 2017.
  3. Flexor Tendon Injuries. http://www.orthobullets.com/hand/6031/flexor-tendon-injuries. Updated: January 23, 2017. Accessed: January 23, 2017.
  4. Schöffl V, Heid A, Küpper T. Tendon injuries of the hand. World J Orthop. 2012; 3 (6): p.62-69. doi: 10.5312/wjo.v3.i6.62 . | Open in Read by QxMD
  5. Henry GI. Extensor Tendon Lacerations. In: Molnar JA, Extensor Tendon Lacerations. New York, NY: WebMD. http://emedicine.medscape.com/article/1286225-workup. Updated: February 16, 2016. Accessed: January 23, 2017.
  6. Makkouk AH, Oetgen ME, Swigart CR, Dodds SD. Trigger finger: etiology, evaluation, and treatment. Current Reviews in Musculoskeletal Medicine. 2008; 1 (2): p.92-96. doi: 10.1007/s12178-007-9012-1 . | Open in Read by QxMD
  7. Malone JC, Preston KS, Garner HW, Bestic JM, Wessell DE, Peterson JJ. MRI of the hand and fingers. APPLIED RADIOLOGY. 2016 : p.9-21.
  8. Boutonniere Deformity. http://www.orthobullets.com/hand/6012/boutonniere-deformity. Updated: January 23, 2017. Accessed: January 23, 2017.
  9. Reizner W. Boutonniere Deformity. In: Gellman H, Boutonniere Deformity. New York, NY: WebMD. http://emedicine.medscape.com/article/1238095. Updated: January 11, 2016. Accessed: January 23, 2017.
  10. Gammons M. Ulnar collateral ligament injury (gamekeeper's or skier's thumb). In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/ulnar-collateral-ligament-injury-gamekeepers-or-skiers-thumb.Last updated: December 9, 2016. Accessed: January 23, 2017.
  11. Sourmelis SV. Repair of the ulnar collateral ligament of the thumb: Technique and outcome in 21 patients followed for minimum 1.5 years. Acta Orthop Scand Suppl. 1997; 275 : p.52-54.
  12. Trauma X-ray: Upper limb Hand/fingers. http://www.radiologymasterclass.co.uk/tutorials/musculoskeletal/x-ray_trauma_upper_limb/hand_finger_trauma_x-ray. Updated: January 23, 2017. Accessed: January 23, 2017.