The Case

A grade schooler had a finger on his left hand awkwardly slammed in the car door on accident when his sibling was rushing to get into the house first. There is a laceration across the base of the nail, and he is in a lot of pain. The X-Rays show the following (image courtesy of Radiopedia).

Case courtesy of Dr Abdelrashed Abdelmoez Elmelegy Seleem, Radiopaedia.org. From the case rID: 41965

The Diagnosis

The combination of the displaced physical injury of the distal phalanx and the nailed laceration is what is known as a Seymour fracture. On exam you will note a mallet deformity as well as bruising and swelling. The nail plate will be superficial to the eponcyhial fold and soft tissue can be “pulled into” the plane of the fracture. Here is a diagram of what that might look like.

Courtesy: Prof Nabil Ebraheim, University of Toledo, Ohio, USA

Mallet finger is also on the differential. In contrast to the Salter Harris II (or sometimes SH I) fracture that transverses the physis in the Seymour fracture a mallet finger is usually a Salter Harris III or IV avulsion fracture that enters the DIP joint. There are also no nailbed lacerations to contend with.

Obviously you will need X-Rays to make the diagnosis. The PA can look more “normal” but the lateral will show the marked displacement. The middle finger is the most common.

Management

This is one where calling a hand surgeon is a very good idea. Make sure the patient has adequate analgesia and that their tetanus status is up to date. Management of the Seymour fracture is often operative. In general the hand surgeon will make the following distinction when moving forward.

  • Closed reduction and splinting for the minimally displaced closed fracture with no interposition of soft tissue at the fracture site
  • Closed reduction and pinning in the minimally displaced closed fracture with no soft tissue interposed at the fracture site
  • Open reduction and pinning + nailbed repair for the open fracture. The latter one definitely gets antibiotics. Cephalexin, clindamycin, or amoxicillin/clavulanate.

Overall most Seymour Fractures can be dealt with in the Emergency Department – but you should consult hand if you are unsure how to proceed.

References

Abzug JM, Kozin SH. Seymour fractures. J Hand Surg Am. 2013;38:2267–2270. 

Knipe. Seymour Fracture – Radiopedia.org. Accessed, August 13, 2020.

Krusche-Mandl I, Kottstorfer J, Thalhammer G et. Al. Seymour fractures: retrospective analysis and therapeutic considerations. J Hand Surg Am. 2013 Feb;38(2):258-64. doi: 10.1016/j.jhsa.2012.11.015.

Watts. Seymour Fracture. Ortho Bullets. Accessed, August 13, 2020.