Endgames Picture Quiz

A footballer’s finger injury

BMJ 2013; 347 doi: http://dx.doi.org/10.1136/bmj.f5069 (Published 15 August 2013) Cite this as: BMJ 2013;347:f5069
  1. Stephen J Goldie, specialist trainee registrar, plastic surgery12,
  2. Harry W Sargeant, foundation year 2 trainee12,
  3. Karima Medjoub, specialist trainee registrar, plastic surgery12,
  4. Philippa Rust, consultant, orthopaedic hand surgery2,
  5. William Anderson, consultant, plastic surgery12
  1. 1Department of Plastic Surgery, Royal Hospital for Sick Children, Edinburgh EH9 1LF, UK
  2. 2Department of Plastic Surgery, St Johns Hospital, Livingston, UK
  1. Correspondence to: S J Goldie Stephen_goldie{at}hotmail.com

A 12 year old right hand dominant boy sustained an injury to his left middle finger while playing football. On examination, the base of the nail was displaced superficially to the nail fold, with an apparent mallet deformity. The finger was neurovascularly intact. Pain in the finger restricted movement but the flexor and extensor tendons were thought to be intact. Plain lateral and posteroanterior radiographs (fig 1) of the finger were taken in the emergency department.

Figure1

Fig 1 Plain lateral (left) and posteroanterior (right) radiographs of the injured left middle finger

The boy was otherwise well and was taking no regular drugs. He had previously sustained several sporting injuries.

Questions

  • 1 What abnormality do the posteroanterior and lateral radiographs show?

  • 2 How would this injury be classified?

  • 3 How should this injury be managed?

  • 4 What are the potential complications of this injury?

Answers

1 What abnormality do the posteroanterior and lateral radiographs show?

Short answer

The radiographs show a displaced transphyseal fracture of the terminal phalanx of the left middle finger.

Long answer

This fracture was first described by Seymour in 1966 as a juxta-epiphyseal fracture of the terminal phalanx of the finger.1 This was the first time that displaced physeal fractures had been mentioned and guidance given on the appropriate treatment. Seymour reported a series of 20 patients treated with reduction of the fracture and replacement of the nail plate under the nail fold to act as a splint. This management led to a more favourable outcome than K wiring.1 A lateral radiograph clearly shows that the fracture is not a true mallet deformity—it is caused by a physeal fracture rather than disruption of the extensor mechanism. Rupture of the extensor tendon, or avulsion fracture at the insertion of the extensor tendon, is less common in childhood because the physis, or growth plate, is weaker than the tendon. In this case, avulsion of the nail bed suggests that the injury is distal to the insertion of the extensor tendon.

The hand is the most commonly injured part of a child,2 with the little finger and thumb most commonly affected.3 Non-physeal fractures are more common than fractures through the physis, 90% of which are Salter-Harris type II. The mean age for children under 16 years old to sustain a hand fracture (excluding wrist and distal radius) is 11 years—most fractures occur in boys as the result of a sport related injury.4 The mechanism in this case is slightly unusual for a Seymour fracture, which is more typically caused by crush injury in a door. The incidence of Seymour fractures is difficult to estimate because of a lack of data, although a review of 700 000 children with fractures of the phalanges identified four such fractures.5 This fracture may be uncommon, but it can lead to complications and malunion if not treated correctly.

The original description is of an open fracture of the terminal phalanx, with avulsion of the nail bed. This is because the nail root is close to the underlying bone. Traumatic displacement means that the fragile underlying matrix will probably be ruptured, exposing the fracture beneath. Thus, the later literature refers to the fact that a Seymour fracture is by definition open.2

2 How would this injury be classified?

Short answer

It would be classified as a Salter Harris type II fracture (the fracture line is through the physis and it extends out through the metaphysis).

Long answer

In a Seymour fracture, the fracture line passes through the physis of the terminal phalanx with volar angulation of the long axis of the phalanx on the epiphysis (fracture apex dorsal). This relates not only to the force of impact of the injury but the tendon insertion sites and any soft tissue interposition. The flexor digitorum profundus tendon attaches to the metaphysis, whereas the terminal extensor tendon inserts into the epiphysis.6 The fracture separates the pull of these tendons, and the unopposed action of the flexor digitorum profundus tendon on the distal phalanx results in volar angulation of the diaphysis. These fractures are usually Salter-Harris type II fractures, although in adolescents they can be 1-2 mm distal to the physis and therefore not Salter-Harris fractures. In our case, the fracture is through the physis, with a small fragment through the metaphysis, making it a Salter-Harris type II fracture. The metaphyseal fragment of the Salter-Harris type II fracture is called the Thurston-Holland fragment.

3 How should this injury be managed?

Short answer

It is important to recognise that this is an open fracture that needs reduction. The patient should be covered for tetanus and given antibiotics to protect against possible infection. After thorough washout and debridement, the finger should be manipulated under anaesthesia to reduce the fracture. It should then be stabilised by K wiring, followed by repair of the nail bed.

Long answer

Seymour originally described a technique for returning the nail into its proximal nail fold, then applying a gently hyperextension force to reduce the fracture. This can be held with a metal splint. K wire fixation is currently the favoured option because of evidence that non-operative treatment is associated with non-adherence and infection.7 The fracture should be thoroughly washed out through the nail bed wound and debrided. Any interposing soft tissue must be removed from the fracture site before reduction. It can then be fixed by a single pass of a smooth K wire. The nail bed should be carefully repaired, with replacement of the nail. Tetanus cover and administration of antibiotics help protect against possible infection of the open fracture.2

4 What are the potential complications of this injury?

Short answer

Infection, delayed union (sometimes because of infection, but often owing to sterile matrix interposition), and malunion.

Long answer

The complications of infection and ostoemyelitis were illustrated in the original paper, as was volar angulation deformity as a result of malunion.1 Direct injury to the physis can cause premature closure of the growth plate. Treatment after prompt diagnosis with modern techniques should reduce these complications. However, malunion can still cause “pseudoclaw” deformity of the nail, which sometimes requires secondary reduction and internal fixation.7 Nail bed laceration can result in permanent nail deformity, so repair must be performed carefully.

Patient outcome

The patient was taken to theatre for debridement and repair of the wound under general anaesthesia. Local anaesthetic was injected as a ring block to aid postoperative pain relief. The fracture was reduced and a single 1 mm smooth K wire was passed through the physis and joint to keep the finger stable (fig 2). The nail bed was repaired with a 6-0 vicryl rapide suture. The nail was cleaned and replaced to splint the nail bed. A small plaster of Paris splint was fashioned to hold the finger in extension. He continued on broad spectrum oral antibiotics for one week and returned for regular wound checks and dressing changes. After four weeks, a repeat radiograph showed that the fracture was healing in a good position, so the K wire was removed. He was advised to mobilise the finger but to abstain from contact sports for a further six weeks.

Figure2

Fig 2 Lateral (left) and posterioanterior (right) radiographs of the reduced finger fracture. A single K wire can be seen in situ

Notes

Cite this as: BMJ 2013;347:f5069

Footnotes

  • Competing interests: We have read and understood the BMJ Group policy on declaration of interests and declare the following interests: None.

  • Provenance and peer review: Not commissioned; externally peer reviewed.

  • Patient consent obtained.

References