Missouri Revised Statutes Title XXX. Domestic Relations § 452.080. Decree for alimony--a lien, when

Upon a decree of divorce, the court may, in its discretion, decree alimony in gross or from year to year.  When alimony is decreed in gross, such decree shall be a general lien on the realty of the party against whom the decree may be rendered, as in the case of other judgments.  When such decree is for alimony from year to year, such decree shall not be a lien on the realty as aforesaid, but an execution in the hands of the proper officer, issued for the purpose of enforcing such decree, shall constitute a lien on the real and personal property of the defendant in such execution, so long as the same shall lawfully remain in the possession of such officer unsatisfied.  In lieu of the lien of such decree for alimony from year to year, it is hereby provided that the party against whom such decree may be rendered shall be required to give security ample and sufficient for such alimony;  but where default has been made in giving such security, the decree for alimony from year to year shall be a lien as in case of general judgments.