TRANSIENT LAXITY OF AN ANTERIOR CRUCIATE LIGAMENT-RECONSTRUCTED KNEE RELATED TO PREGNANCY

Transient laxity was documented around the end of pregnancy in a woman who had undergone anterior cruciate ligament (ACL) reconstruction 2 m onths before conception. This temporary laxity in the 3rd trimester an d a few months postpartum corresponded to a time when substantial remo deling from large diameter to small diameter collagen fibers has been noted in the ACL graft ligamentization process. This is also a time of high levels of the hormone relaxin (member of the family of insulin-l ike growth factors), whose action in animals leads to dissociation of large collagen fibrils to smaller disorganized fibrils. The temporary laxity resolved. Careful observation of women who become pregnant in t he first few months after ACL reconstruction is recommended.