I was hoping to get a response back from my request for more information from you before answer, but I want you to have an answer.
A stiff legged walk or swaying walk at this age could indicate early hip dysplasia. You will often see a bunny hop type movement when they are running as well. Labs are prone to hip dysplasia as well. I would have a thorough exam done by your vet and have him check for hip issues. Since he is young, it may take time before it can be ruled out completely. Some things that can help if he does seem to be more prone to hip dysplasia is to be sure he gets regular exercise and isn't crated all the time and only let out for brief periods of exercise. Be sure he is fed a good quality puppy food designed for large breeds. It has the proper ratios to help prevent hip dysplasia.
As for pet insurance, some policies are worth the cost and some are not. Many just cover well visits such as vaccinations, parasite checks and heartworm preventative. Others cover illness, accident without genetic issues covered while others cover hereditary issues. Other policies cover both and hereditary problems. If it covers all visits with a low or no deductible, then it might be a good policy. This is why it is a good idea to compare various policies and don't just sign up with the first plan offered. The following site gives you the top 10 rated insurances.
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