While there are many different medical "wives-tales" out there, this is one that seems to be supported by many patients testimonies throughout history. Classically people think of the 2 old men sitting on their front porch rubbing their aching knees and predicting the upcoming thunderstorm that is approaching. Also people say that they get "sick" more frequently with the changing of the weather (i.e. bring an umbrella or you'll catch a cold...) Weather changes in and of themselves don't actually cause illness
. There is nothing infectious about weather (unless viruses or pathogens are carried in the wind). However, with the change in weather, comes a change in barometric pressure. Your body becomes used to functioning in a certain climate, and at a particular barometric pressure. Mild to moderate changes in the barometric pressure can throw off your equilibrium, and put you at greater risk for some ailments. Usually if the pressure change is constant, your body will equilibrate over time, and you will go back to functioning properly. One good example of this is "altitude sickness". The people that live in high altitudes have equilibrated to that barometric pressure. However visitors (like climbers) are there for a short period of time and as a result they feel "under the weather", or worse... My best guess is that these barometric pressure changes are felt in your knee which has for some reason been sensitized to the changes after having surgery
. If you are at all concerned about the status of, or hardware in, your knee I would recommend making an appointment with an orthopedic surgeon
to be evaluated. I hope that this was helpful and I wish you all the best.