The knee is one of the joints most often injured with athletic activity. Hopefully yours will be back to normal in no time! However, there are several different possibilities for what could be causing your pain. The kneecap (or patella) itself could be either subluxed or dislocated. It is possible to develop a patellar fracture
, although that usually involves a direct trauma to the knee. If the patella is not in proper alignment on top of the actual knee joint where the femur (thigh bone) meets the tibia (lower leg bone), it is also possible to develop what is called patello-femoral syndrome as the patella grates on the bones it is supposed to be protecting. Finally, as you suggested, there are several soft tissue structures in the knee that help maintain proper alignment, including the posterior and anterior cruciate ligaments within the knee joint itself as well as the lateral collateral and medial collateral ligaments on each side. A 'funny' landing after a jump could carry enough force to cause an injury
to one or more of these ligaments, also leading to pain.
The best thing to do is set up an appointment with an orthopedic surgeon
. He or she will want to hear more about the accident but, most importantly, will want to examine your knee for evidence of swelling or instability that may suggest what is going on as well as what kind of imaging may be necessary. In the meantime it's probably best to try to stay off the knee as much as possible, but hopefully you'll be back to basketball in no time!