Brachydactyly - observation

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.