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The prevalence of cervical ribs in a London population

Cervical ribs are an important cause of neurovascular compression at the thoracic outlet. Previous studies have shown the prevalence of cervical ribs to be between 0.05 and 3%, depending on the sex and race of the population studied. We examined 1,352 chest radiographs to determine the prevalence of cervical ribs in a London population of mixed sex and ethnicity. Our study found that the overall prevalence of cervical ribs was 0.74% with a higher rate in females compared with males (1.09 and 0.42%, respectively). Of the 10 individuals with a cervical rib, five were on the left, three were on the right and two were bilateral. The presence of elongated C7 transverse processes (transverse apophysomegaly) was also noted. We found a total of 30 elongated transverse processes with an overall prevalence of 2.21%. They were also more common in females (3.43%) than males (1.13%). Clin. Anat. 22:331–336, 2009. © 2009 Wiley‐Liss, Inc.