The aim of the present study is to find out whether fusion of a sinlge level SPECT/CT positive degenerative disc disease leads to a significant improvement of pain and disability.

Chronic back pain (CBP) is a very common clinical problem. It is dominantly caused by degenerative changes, while specific causes such as tumor, trauma or inflammatory conditions are relatively rare. Back pain may be a concomitant symptom of lumbar disc herniation or spinal canal stenosis and is a typical symptom of spondylolisthesis. Magnetic resonance imaging (MRI) plays a key role in the diagnosis, showing in detail the soft structures, vertebral bodies (Modic changes, MC) or signs of facet arthropathy. On the other hand, it also proves a number of clinically silent findings. Degenerative disc disease (DDD) or facet osteoarthritis are most often considered to be a pain generator. The problem, however, is that both entities are very common in the general population without a painful correlate, and there is still controversy in the literature about their role in the genesis of CBP.

Radionuclide bone scintigraphy with single photon emission computed tomography (SPECT) provides functional imaging and is used to detect microcalcification due to increased osteoblastic activity. In the absence of other pathology the foci of increased osteoblastic activity reflex areas of mechanical stress and degenerative change in the skeleton. There is growing evidence about the relationship between DDD, facet arthropathy, and SPECT positivity. Although these findings have been recently confirmed by surgical studies, the evidence about the effect of surgical treatment of SPECT positive lumbar degeneration is still weak due to the small number of operated patients.

The aim of the present study is to define a possible correlation between degenerative changes of the lumbar spine and positivity on SPECT/CT imaging. Patients with a single level SPECT+ DDD will undergo spinal fusion of the involved segment. Postoperative improvement will be measured by ODI (Oswestry Disability Index) and pain VAS (Visual Analogue Scale) in 6 and 24 months follow-up period.

Inclusion Criteria:

• Lower back pain (in extension +/- pain in buttocks, groin, thigh) without radicular pain
• Symptoms > 6 months after failure of conservative management in the primary care setting
• MRI signs of degenerative disc disease or facet arthropathy
• One-level positivity on lumbar SPECT/CT

Exclusion Criteria:

• Other spinal pathology (tumours, congenital defects, spondylolysis or spondylolisthesis)
• Intolerance of SPECT examination
• Pregnancy

An open prospective cohort study will be performed. Inclusion criteria will be: subjects between 18 and 75 years of age; both genders; with CBP and diagnosis of DDD or facet arthropathy on MRI and increased metabolic activity on bone SPECT/CT imaging in the same level(s) who are undergoing open lumbar interbody fusion. New MRI of the lumbar spine and SPECT/CT will be performed 2 years after the surgical procedure. The patients will complete ODI and VAS questionnaires before surgery and at 6- and 24-months follow-up visits. All patients will sign an informed consent form.