A spinal distraction system, according to one aspect, includes an adjustable spinal distraction rod comprising first and second members, the adjustable spinal distraction rod configured for non-invasive elongation of the first and second members. The system includes an anchor rod configured for mounting to a bone of a subject, the anchor rod having one or more spring-biased tabs disposed at one end thereof, and a connector having first end and a second end, the first end having a receiving cup configured for detachable mounting on the anchor rod, wherein the one or more spring-biased tabs are configured to engage with an inner surface of the receiving cup, the connector having a second end operatively coupled to an end of a first member and wherein the second member is configured for mounting to a second bone of a subject.