Treatment of internal disc derangement by posterior lumbar interbody fusion and posterior instrumentation

Internal disc derangement (IDD) is characterized by chronic low-back pain and referred pain in the legs. This condition is easily misdiagnosed as a disc herniation, resulting in failed back surgery, or it could be ignored by a doctor as malingering or a psychological problem. The indication of surgery has been intractable low-back pain with or without leg pain in spite of conservative treatment over 6 months. Discography was performed before surgery, and painful disc(s) were identified by concordant pain provocation. Subtotal disc excision and posterior lumbar interbody fusion (PLIF) with posterior instrumentation were performed. A successful clinical and radiological result was obtained by these procedures. The cause of IDD and the mechanisms of pain are discussed.