Luxating patella is another health issue in the Pomeranian breed.[1] It occurs when, through either malformation or trauma, the ridges forming the patellar groove in the knee are not prominent and are too shallow to allow the patella to properly sit securely. This can cause the patella to "luxate" (jump out of the groove) sideways which will cause the leg to lock up with the foot off the ground.[20] While the muscles are contracted the patella cannot return to the correct position.