Degenerative Disc Disease ICD-9
Degenerative Disc Disease Etiology / Epidemiology / Natural History
- 90% of people >60y/o have disc degeneration, most are asymptomatic (Boden SD, JBJS 1990;72A:1178).
- There is no set definition of DDD, with aging degenerative disc disease begins with disc loss of proteoglycans and dehydration, tear formation within the annulus fibrosis and progressive fraying and dehydration of the nucleus pulposes with eventual loss of disc height etc. As degeneration advances load transmission is shifted to the posterior elements causing facet overload/arthritis/osteophytes.
- Disc degeneration procedes through 3 stages: temporary dysfunction, unstable, stabilization. Procedes over 20-30 years (Kirkaldy-Willis WH, CORR 1982;165:110).
- Risk Factors: age, family history, smoking, chronic vibration (prolonged driving), heavy repetitive loading of the spine(jackhammer/machine tools), diabetes.
Degenerative Disc Disease Anatomy
- Anulus fibrosus = type 1 collagen oriented at 30 angles from the long axis of the spine.
- Nucleus pulposus = proteoglycan rich matrix with randomly oriented primarily type II collagen.
- Lumbar spinal canal is divided into 3 regions:
-Central Zone: region between the lateral margins of the dura.
-Lateral Recess: between the lateral magin of the dura and the medial border of the pedicle.
-Foraminal Zone:between the medial and lateral margins of the pedicle. Contains the intervertbral foramen.
Degenerative Disc Disease Clinical Evaluation
- Typically transverse low back pain with radiation into the sacroiliac region.
- May have lower extremity claudication in concomitant lumbar stenosis is present.
- Radicular pain indicates disk herniation or foraminal stenosis.
- Pain often worsened with flexion and improved with extension. Pain with extension indicates facet joint arthritis.
- Straight leg raise generally negative.
- Due abdominal exam to rule out intraabdominal pathology. See differential diagnosis.
Degenerative Disc Disease Xray / Diagnositc Tests
- A/P and lateral lumbar spine views +/- flexion-extension views if concerned for spondylolisthesis. Eval for: osteophytes, foraminal narrowing, end-plate sclerosis, disk space narrowing, vacuum phenomenon within the disk
- MRI: Evaluate disk height, annular tears, degeneration(decreased signal on T2-images), end plate changes. 30% of aysmptomatic individuals have changes on MRI (Boden SD, JBJS 1990;72A:403).
- Modic Changes (Modic MT, Radiology 1988;168:177)
-Type I: decreased signal intensity on T1-images, increased signal on T2-images
-Type II: increased signal intensity on T1-images and isointense or slightly increased signal on T2 images.
-Type III: decreased signal on both T1- and T2-images
- Discography: patient's pain must be reproduced at low pressure/volume injection at the concordant disc. Dye extravasation through the anulus further validates the exam. Exam should include injection pressure monitoring and postinjection pressure 25% false postive results for chronic low back pain patients (Carragee EJ, Spine 2006;31:505).
Degenerative Disc Disease Classification / Treatment
- Observation: 90% of patients with low back pain resolves within 3 months with or without treatment (Andersson GB, Lancet 1999;354:581).
- Physical therapy: core strengthening, body mechanics education
-McKenzie method: highly effective (May S, Spine J 2008;8:134).
- Chiropractic manipulation: equivalent to physical therapy for acute pain (Cherkin DC, N Engl J Med 1998;339:1021). Manipulation not helpful for chonic pain.
- Back schools (Heymans MW, Spine 2006;31:1075) (Heymans MW, Spine 2005;30:2153).
- NSAIDs effective for short term symptoms. Muscle relaxants, tricyclic and tetracyclic antidepressants somewhat effective but with high side-effect profiles.
- IDET: no better than placebo (Freeman BJ, Spine 2005;30:2369).
- Lumbar arthrodesis: historically had 68% patient satisfaction (Turner JA, JAMA 1992;268:907). More recently has shown superior outcomes compared to nonsurgical care (Fritzell P, Spine 2001;26:2521).
- Total Disc Replacement:
Degenerative Disc Disease Associated Injuries / Differential Diagnosis
- Intraabdominal pathology: kidney stones, aortic aneursym, pancreatic disease, tumors.
- Lumbar spinal stenosis
- Facet arthrosis
Degenerative Disc Disease Complications
Degenerative Disc Disease Follow-up Care
Degenerative Disc Disease Review References
- Madigan L, JAAOS 2009;17:102