A herniated disc can be divided into two types, supra-shoulder and axillary, in terms of the relationship between the disc and the nerve. Different relationships of herniation lead to different signs. If the herniated disc is lateral to the nerve (supra-shoulder type), the patient has no pain when the spine is bent to the healthy side, but the pain radiates to the lower leg if the patient is bent to the diseased side; if the herniated disc is medial to the nerve root (axillary type), the patient has radiating pain when the patient is bent to the healthy side, but no pain if the patient is bent to the diseased side; if the herniated disc is up against the nerve root, or if there is adhesion between the two, there is pain whether the patient is bent to the diseased side or to the healthy side.