Ossification of the posterior longitudinal ligament. Autosomal recessive trait.

STUDY DESIGN

This study analyzed the mode of inheritance of ossification of the posterior longitudinal ligament (OPLL) from the pedigree of a family.

OBJECTIVES

The results were correlated to provide a new mode of inheritance of OPLL.

SUMMARY OF BACKGROUND DATA

Although a nation-wide multicenter survey of OPLL has been carried out in 347 subjects and 1030 relatives in Japan since 1981, no parental consanguinity has been reported.

METHODS

In the family, three siblings and one other member of a family underwent operations for OPLL in our department, and the clinical information regarding other family members was obtained from interviews with these four patients or relatives.

RESULTS

The parents of three affected siblings and another unaffected sister were first cousins, and the father was suspected to be affected as well.

CONCLUSION

Transmission of OPLL as an autosomal recessive trait in this family, which has not been reported, is suspected; although, the possibility that it is a dominant trait can not be excluded.