Kirner's deformity

A Kirner deformity, also known as dystelephalangy, is characterized by a curvature of the distal phalanx of the 5 digit in both a palmar and radial direction.

Epidemiology

The deformity typically presents in late childhood to early adolescence, although a mild deformity may be present at birth. Both sexes are affected, although there is a predominance of cases in women reported, perhaps indicating a gender predilection .

Inheritance has been described as autosomal dominant with variable penetrance, however many cases appear sporadic .

Associations

Associations may include:

• Down syndrome
• pes cavus
• absence of the flexor digitorum superficialis tendon in the 5digit
• myositis ossificans
• Turner syndrome
• Silver syndrome
• Cornelia de Lange syndrome
• congenital cardiac abnormalities
  • ventricular septal defect (VSD)
  • patent ductus arteriosus (PDA)
  • atrial septal defect (ASD)
  • pulmonary artery stenosis

Clinical presentation

Although the presentation is usually with deformity, in some patients swelling and erythema may be present .

Radiographic features

Radiographic changes affect the terminal phalanx of the 5 digit, in most cases bilaterally, and are characterized as:

• palmar and radial deviation
• radiolucent nidus (1-2 mm) within the terminal tuft
• shortened diaphysis
• sclerosis of the diaphysis
• metadiaphyseal defect

Treatment and prognosis

As this is purely a cosmetic problem (unless fine motor skills are required) medical treatment is optional. It is unclear whether splints alter the degree of deformity .  Osteotomy is an option if treatment is deemed necessary.

History and etymology

It was first described by J Kirner in 1927 .

Differential diagnosis

Consider

• clinodactyly: radial deviation at the DIP joint
• camptodactyly: flexion deformity at the PIP joint
• frostbite

Siehe auch:

• Klinodaktylie
• Kamptodaktylie