Gould (1942) described the condition in grandfather, father and son, i.e., males of 3 generations. X-rays were not described. Exostosis of the heel, possibly of the same type, is a manifestation of the Reiter syndrome, a rheumatic disorder that shows a high order of association with a specific HLA type (142800), namely B27 (Brewerton et al., 1973; McClusky et al., 1984; Woodrow et al., 1974). Thus might familial aggregation be accounted for.
Brewerton, D. A., Nicholls, A., Oates, J. K., Caffrey, M., Walters, D., James, D. C. O. Reiter's disease and HL-A 27. Lancet 302: 996-998, 1973. Note: Originally Volume II. [PubMed: 4127280] [Full Text: https://doi.org/10.1016/s0140-6736(73)91091-x]
Gould, E. A. Three generations of exostoses of the heel. Inherited from father to son. J. Hered. 33: 228 only, 1942.
McClusky, O. E., Lordon, R. E., Arnett, F. C. HL-A 27 in Reiter's syndrome and psoriatic arthritis: a genetic factor in disease susceptibility and expression. J. Rheum. 11: 571 only, 1984. [PubMed: 6334736]
Woodrow, J. C., Treanor, B., Usher, N. The HL-A system in Reiter's syndrome. Tissue Antigens 4: 533-540, 1974.