Found this article which seems similar to the theory of a rupture in the sperm ducts potentially causing problems.

1: J Urol. 1986 Dec;136(6):1224-7.
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Diverticula of the ductus epididymis in men.

Nistal M, Iniguez L, Paniagua R, Regadera J.

The histological study of epididymides obtained from autopsies (41 children, 7 young adults and 8 elderly men) and surgical specimens (10 young adults and 3 elderly men) revealed the presence of multiple diverticula in the cauda epididymis in all elderly men and in only 2 young adults (32 and 33 years old). The diverticula appeared as evaginations of the epithelial lining of the duct, disrupting the muscular coat and expanding into the surrounding connective tissue. The formation of epididymal diverticula seems to be an age-related process that might be caused by repeated increases in the intraluminal pressure in the cauda epididymis.

PMID: 3095567 [PubMed - indexed for MEDLINE]