Hand Surgery Source

Brachydactyly - observation

Test, Exam and Signs

Historical Overview

  • Brachydactyly derives from the Greek words “brachy,” short, and “daktylos,” digit.1
  • Brachydactyly is the first reported human condition found to follow Mendelian laws of inheritance.2

Description

  • Brachydactyly is diagnosed primarily through the observation of shortening of the digits. It can be divided into 3 groups: simple shortening of the digits, ankylosis of the bones of the digit, and partial loss of bone.
  • Brachydactyly Type C may cause ulnar deviation of the index finger and digital scissoring.3
  • Brachydactyly can occur as an isolated event or as part of a complex malformation syndrome.1 Associated syndromes include Down’s syndrome and Cushing’s syndrome. Prenatal diagnosis may be useful for syndromic forms of brachydactyly.1

Pathophysiology

  • Brachydactyly usually occurs as an autosomal dominant gene with variable expression.

Instructions

  1. Obtain an accurate and complete patient history, including a family history. If possible, a clinical evaluation of first-degree relatives would also aid in diagnosis.
  2. Ask the parent or guardian if the patient experiences any loss of function in the hands.
  3. Examine both the hands and feet of the patient for shortening of the digits.
  4. Check for broad thumbs and nail deformity.

Variations

  • Determine whether bone loss is involved in the shortening of the digits. Radiographs are useful to determine what bones are affected.4

Related Signs and Tests

  • Range of motion (ROM), active
  • ROM, passive
  • Grip strength
  • Joint exam
  • Pinch strength
  • Radiographs

Diagnostic Performance Characteristics

  • Use other physical tests and radiographs to improve reliability.
Presentation Photos and Related Diagrams
Bilateral Ring Finger Brachydactyly
  • Bilateral Ring Finger Brachydactyly (arrows) secondary to shortened ring metacarpals
    Bilateral Ring Finger Brachydactyly (arrows) secondary to shortened ring metacarpals
Definition of Positive Result
  • A positive result occurs when shortening or ankylosing of digits are observed.
Definition of Negative Result
  • A negative result occurs when digits appear normal without shortening or ankylosing.
Comments and Pearls
  • In some cases, hand function may be improved by physical therapy and ergotherapy.1 
  • Be vigilant when choosing operative treatment for brachydactyly; surgical treatment may cause additional shortening of the fingers. 
  • Brachydactyly Type C can be treated with corrective osteoplasty.3

Differential Diagnoses

  • Clinodactyly
  • Camptodactyly
  • Symphalangism
  • Kirner’s deformity
  • Pseudohypoparathyroidism
Diagnoses Associated with Tests, Exams and Signs
References
  1. Temtamy SA, Aglan MS. Brachydactyly.Orphanet J Rare Dis2008;3:15. PMID: 18554391
  2. Marshall R. Note on a family with brachydactyly. Arch Dis Child1929;4(24):385-8. PMID: 21031787
  3. Burgess RC. Brachydactyly type C. J Hand Surg Am2001;26(1):31-9. PMID: 11172365
  4. David A, et al. Isolated and syndromic brachydactylies: diagnostic value of hand x-rays. Diagn Interv Imaging2015;96(5):443-8. PMID: 25758756