Diagnosis
During the physical exam, your doctor will move your leg, and especially your hip joint, around in various positions to check for pain and evaluate your hip's range of motion. He or she may also want to watch you walk.
Imaging scans
A hip labral tear rarely occurs in isolation. In most cases, other structures within the hip joint also have sustained injuries. X-rays are excellent at visualizing bone. They can check for fractures and for structural abnormalities.
Detailed images of your hip's soft tissues can be provided through magnetic resonance imaging (MRI). A contrast material may be injected into the hip joint space to better define a labral tear if one exists.
Anesthesia injection
Hip pain can be caused by problems within the joint or outside the joint. Your doctor may suggest injecting an anesthetic into the joint space. If this relieves your pain, it's likely that your problem is inside your hip joint.
Source: http://www.mayoclinic.com