There are a number of potential causes of Hornerâs syndrome, each affecting a different place in the sympathetic chain: 1  First order neuron lesion: brainstem stroke. 2  Second order neuron lesion: apical lung tumor, neck trauma, other. 3  Third order neuron lesion: orbital trauma or inflammation, carotid dissection, other.
In very severe cases where the patella keeps dislocating, the attachment of the patellar tendon may also have to be moved. Once the surgery heals, the patella will track up and down in the patellar groove, reducing pressure on the articular cartilage. 1  Knee Pain: Symptoms, Causes, and Treatments.
After knee replacement surgery, you should not pivot or twist on the involved leg for at least six weeks. Also during this time, when lying in bed, you should keep the involved knee as straight as possible. Kneeling and squatting also should be avoided soon after knee joint replacement surgery.