The preoperative examinations that are necessary for a correct diagnosis include x-rays, dynamic x-rays, magnetic resonance imaging (MRI), facet blocks, and discography.

Plain x-rays demonstrate single- or multiple-level DDD, spondylolisthesis, and spondylolytic problems. Spondylodiscitis, infections, spinal tumors, translational instabilities and retrolisthesis/anterolisthesis are identified on anteroposterior and lateral views. Dynamic x-rays disclose ligamentous hypermobility and anteroposterior slip due to instability.

MRI provides an appreciation of disc degeneration, with or without Modic changes and also detects disc fragment expulsion, disc herniation, discitis, tumors, and fractures.

In cases of radiographic suspicion of osteoporosis and in female patients older than the age of 45 years preoperative dual-energy x-ray absorptiometry (DEXA) is mandatory.

Facet blocks at the involved level can indicate whether the facet joints are the pain generators. If they are, complete pain relief will be obtained after injection of lidocaine. If the pain fails to disappear, it does not originate in the facet joints.

Discography is one of the most important examinations. Through the injection of radio-opaque fluid the pressure in the affected disc is increased. If the disc is pathologic, the pain the patient experiences in daily life can be reproduced. Discography at the level above and below the “black disc” is very important to document that the affected disc actually is the pain source in that particular patient.