Shortening of the fourth/fifth metacarpals

Last revised by Rohit Sharma ◉ on 17 Feb 2025

Citation, DOI, disclosures and article data

Citation:

Dawes L, Sharma R, Nicoletti D, et al. Shortening of the fourth/fifth metacarpals. Reference article, Radiopaedia.org (Accessed on 08 Mar 2025) https://doi.org/10.53347/rID-2041

DOI:

https://doi.org/10.53347/rID-2041

Permalink:

https://radiopaedia.org/articles/2041

rID:

2041

Article created:

2 May 2008, Laughlin Dawes

Disclosures:

At the time the article was created Laughlin Dawes had no recorded disclosures.

View Laughlin Dawes's current disclosures

Last revised:

17 Feb 2025, Rohit Sharma ◉

Disclosures:

At the time the article was last revised Rohit Sharma had no financial relationships to ineligible companies to disclose.

View Rohit Sharma's current disclosures

Revisions:

26 times, by 16 contributors - see full revision history and disclosures

Systems:

Musculoskeletal

Sections:

Gamuts

Synonyms:

Short fourth metacarpals
Short fourth metacarpal
Shortened fourth metacarpal
Short 4th and 5th metacarpals
Short 4th / 5th metacarpal
Brachymetacarpia

Shortening of the fourth/fifth metacarpals (brachymetacarpia) and less commonly metatarsals (brachymetatarsia) is seen in a variety of apparently disparate conditions.

Pathology

Etiology

Common causes ²:

idiopathic
post-infective (e.g. osteomyelitis, yaws, tuberculosis dactylitis)
pseudohypoparathyroidism/pseudopseudohypoparathyroidism
post-traumatic (acute or chronic/healed and particularly those involving growth plate)
Turner syndrome

Uncommon causes ²:

basal cell nevus syndrome (Gorlin syndrome)
hereditary multiple exostosis syndrome ⁵
juvenile idiopathic arthritis
sickle cell disease with secondary infarction
homocystinuria
Langer-Giedion syndrome

Isolated shortening of the 5^thmetacarpals has been described in a familial variant of type 1 diabetes mellitus ³.

Radiographic features

Plain radiograph

Hand x-rays readily identify the abnormality and can be assessed by drawing a line along the heads of the 4^th and 5^th metacarpals. If this line intersects the head of the 3^rd metacarpal then shortening is deemed to be present.

Thus, shortened 4^th metacarpal is the key to this finding. It is known as the metacarpal sign. It is important to note that a positive sign can be seen in up to 10% of normal individuals ⁴.