Srdjan Mirkovic

1. Incapacitating discogenic low back pain

2. Spinal stenosis with instability

3. Spondylolisthesis

4. Scoliosis or kyphosis

5. Pseudoarthrosis

6. Instability adjacent to a previous fusion

7. Re-do lumbar discectomy.

1. Spinal stenosis without deformity or known risk for deformity

2. Primary discectomy

3. Low back pain associated with multi-level degenerative disc disease

1. Medical and anesthetic evaluation

2. Anteroposterior (AP), lateral, oblique, and flexion extension X-rays

3. Lumbar imaging (MRI, CT myelography)

4. Consider electrodiagnostic studies.

5. Consider preoperative diagnostic studies (facet blocks, SI blocks, discograms, nerve root blocks).

6. Preoperative neurovascular assessment

7. Attempt to establish realistic expectations.

8. Encourage the patient to discontinue smoking. If possible, cessation of smoking should occur 6 months prior to the fusion.

1. The prone position is used for posterior spinal fusions.

2. Position the hips in neutral or slight extension. This helps maintain lumbar lordosis, which is imperative.

3. All pressure points should be carefully padded. The abdomen and genitalia (in males) should hang free. The arms must be placed in a 90/90 position to avoid brachial plexus traction injury. The ulnar nerve should be protected.

4. The lower extremities are placed in anti-embolic stockings and compression boots.

5. Spinal cord monitoring may be used.

6. X-rays and fluoroscopy should be available for verification of the appropriate level and in the case of instrumentation, to verify appropriate instrumentation placement.

7. If fluoroscopy is to be used, the undersurface of the table should be free to allow C-arm rotation.

8. Use specific instrumentation for planned spinal hardware.

9. In revision fusion surgery, determine prior to surgery which iliac crest(s) were harvested.

11. Surgical instruments include: Cobb elevators, curettes, kerrosens, rongeurs, pituitaries, Penfields, osteotomes, and gauges.

12. Retractors should include: Hibbs, McCullough, Army-Navy, cerebellar, and deep Gulpies.

13. Bone wax, Cottonoids, gelfoam, and Thrombin should be available.

1. Preoperative planning is paramount in determining the extent of fusion and the site for bone graft harvesting.

2. If instrumentation is to be used, preoperative planning allows determination of the levels of instrumentation and the site for purchase (pedicle, lamina, facet). If pedicle screws are planned, the sagittal and transverse orientation of the pedicles and their width, length, and height should be determined.

3. Imaging studies should be evaluated for the presence of any spinal anomalies.

4. The patient should be positioned in spinal lordosis. This is particularly important when long lumbar fusions are planned; it diminishes the possibility of postoperative flat back syndrome and spinal dysfunction.

5. Intravenous antibiotics are administered preoperatively. In the case of instrumentation, broad gram positive and gram-negative spectrum antibiotics are administered.

6. Paravertebral soft tissue dissection should proceed in a caudal-cephalad direction due to the caudal-cephalad orientation of the paravertebral muscle attachments.

7. The facet joint immediately cephalad to the fusion must be preserved to avoid iatrogenic instability.

8. Dissection should extend to the tips of the spinous processes bilaterally and to the lateral aspect of the facet joints. All soft tissue should be denuded to allow maximal surface area for bony fusion.

9. The majority of the decortication is carried out using sharp instruments such as osteotomes, curettes, and rongeurs.

10. Facet joints should be thoroughly cleared of all soft tissues and the intra-articular portion of the joint denuded of cartilage.

11. If a lumbar decompression has been performed prior to the fusion, the exposed dura should be protected with cottonoids to diminish the likelihood of an iatrogenic dural laceration.

1. Avoid prolonged muscle retraction. Self-retaining retractors should be relaxed every hour and the wound re-irrigated. This allows re-perfusion of the paravertebral muscles and diminishes the possibility of infection. If there is excessive tension on the muscles, the incision can be lengthened.

2. Avoid using an inadequate amount of bone graft; occasionally harvesting of both iliac crests may be necessary and/or augmentation with allograft bone may be needed.