Within the last decade there has been an increase in the number of surgical procedures for deformities of the spine. This is caused by the increase in the elderly population, improved surgical techniques and an increased number of patients who have undergone previous surgical treatment for degenerative conditions of the spine. Surgical treatment of spinal deformities bears a revision rate between 15 and 30% depending on definition, and one of the primary reasons for revision surgery is implant loosening in the lumbosacral region.

The hypothesis of the study is that a procedure resulting in anterior fusion of the lumbar spine in addition to the usual posterior instrumentation can reduce the revision rate with 50%.

Inclusion Criteria:

• 18 years or more of age
• planned posterior instrumented fusion from thoracic spine to sacrum and/or ilium

Exclusion Criteria:

• malignancy
• infection