Collision, Left Knee Hit Below Knee Cap, Swelling, Pain, Fever. Treatment ?
From what you describe, what you have seems like a contusion to the knee. What we want to rule out is a tear of a meniscus or a tear of a cruciate ligament or a tear of the medial collateral ligament. If you go to google you can look up where each of these lies in relation to the knee itself and the patella.
Sometimes collision injuries can cause an injury to any of one of those anatomic components of the knee. If you sense any instability of the knee joint or hypermobility if the knee then I would be more concerned about one of those things.
I am hoping that all you have here is a bad bruise. I recommend you be aggressive about applying ice to the injured part of the knee for 20 minute sessions every 2 hours for the next day. Beyond that I would wrap the knee with an ace wrap to maintain stability and help mobilize some of the fluid swelling out of the knee. I would also keep the leg elevated as much as possible when you are not walking. Finally I would recommend you do some warm soaks in a hot tub or bathtub starting tomorrow. This will also help with the swelling.
In addition, I recommend ibuprofen 800 mg three times daily for the next 5 to 7 days for comfort and also to possibly limit swelling. As forth swelling higher up this may be due to a disturbance in flow of lymphatic fluid from the leg. That swelling should stabilize and slowly improve over time as well.
Lastly - indications to go to be seen include worsening pain or swelling, laxity or instability of the knee or loss of sensation in the lower leg. Again I hope this is only a minor bruise but in case it's not I wanted you to be aware of those other potential points of injury.
I thank you again for your query. I hope my answer was both helpful and informative. Should you have additional concerns I would be happy to address them.
Sincerely,
Dr. Galamaga