I just had a triplet kid on Wednesday, whose hock joints were flopping the wrong way, and I've had numerous lambs over the years that had wobbly joints when they first came out.
With a bit of time and support, the ligaments strengthen and straighten out, it does often seem long legs, multiple births where they've been twisted funny inside are more prone.
Supporting the lamb to stand will help weight to go through the legs and joints, and doing this several times a day will get them right.
Splinting or vetwrapping the lower end of the leg can be counterproductive as the leg then has a lot more weight swinging the joints around, so may be more difficult for the lamb to get the right way round!
My triplet kid from Wednesday already looks much more normal, so it can turn around quite quickly.
Hope that helps
Suzanne