Lumbar DDD, Spinal Stenosis

• 1. Dysfunctional phase (4 things) =

[tear, dehydration, conversion, stiffening]

1. tears of annulus,
2. disc dehydration [DDD, spinal stenosis].
3. There is conversion of type 2 collagen to type 1 fibrocartillage ➔ stiffening of the Nucleus pulposus
• 2. Instability - [spondylolisthesis]
• 3. Restabilization = osteophyte formation, buckling of ligamentum flavum

• 3 types of modic changes described by Modic in 1988
• Type 1 = Hypointense on T1 and hyperintense on T2 (bone marrow edema)

• Type 2 Hyperintense on both T1 and T2 = conversion of red hemapoietic bone marrow into yellow fatty marrow due to marrow ischemia.

• Type 3 = Both T1 and T2 hypointense. = subchondral sclerosis

• Type 1 - found to have more LBP
• Type 1 found to have higher incidence of segmental hypermobility, unstable lesions

• Aseptic gas collection e.g. nitrogen, oxygen or CO2 within the disc
• Closely associated with intervertebral disc degeneration, modic changes and subchondral sclerosis

Intradiscal vacuum phenomenon and spinal degeneration: a cross-sectional analysis of 219 subjects - PubMed

1 Department of Neurosurgery, School of Medicine, Acıbadem Mehmet Ali Aydınlar University, Istanbul, Turkey. 2 Department of Physical Medicine and Rehabilitation, School of Medicine, Bahçeşehir University, Istanbul, Turkey. 3 School of Medicine, Acıbadem Mehmet Ali Aydınlar University, Istanbul, Turkey. 4 School of Nursing, Acıbadem Mehmet Ali Aydınlar University, Istanbul, Turkey.

pubmed.ncbi.nlm.nih.gov

• Red flags
• Neurogenic vs vascular claudication - 3 points
• Bench to bench vs lamp to lamp
• Pain relieved in dependant position
• Neurogenic better when climbing stairs
• Cauda Equina!

• 2 pathophysiology = ischemia and mechanical compression
• Ischemia
• Increased compression leads to reduced spinal canal volume ➔ venous congestion ➔ diminished arterial flow to nerves
• Walking exacerbates oxygen demand
• Mechanical compression
• Direct nerve root compression
• Worse when spine in extension due to buckling of ligamentum flavum

• CLFE
• Central stenosis - will hit traversing roots
• Lateral recess aka subarticular = begins at the medial border of the superior articular process and extends to the medial border of the pedicle - will hit traversing roots aka " paracentral" when used to describe disc
• Foraminal recess [Mid-zone] = between medial and lateral border of pedicles - hit exiting roots
• Extra-foraminal/ Far lateral recess [Exit zone] = lateral to lateral border of pedicle - exitting roots

• It is the process anteriorly

• By anatomical location
• By Etiology
• Congenital - achondroplasia, scoliosis (neuromuscular, idiopathic…), kyphosis
• Degeneration - OA, DISH, Spondylolisthesis
• Metabolic - Paget’s disease

• Physio, analgesia, Neuromodulators - Gabapentin

• Stand for: Spine Patient Outcomes Research Trial
• A multicenter RCT over 13 centers; comparing op vs Non op for Spinal stenosis with and without Spondylolisthesis involving patients published in NEJM 2008 and JBJS in 2009
• "Found that when undergo as treated analysis, Surgery gave better outcomes for both conditions"
• "Aware of criticisms - high loss to follow up (64% left), high cross over rates, no standardized surgery (fuse or no fuse) or non op"
• Results - Spinal Stenosis without Listhesis
• Surgery is decompressive laminectomy only
• Intention to treat analysis – no difference
• As treated Analysis – surgery better for all outcomes
• SPORT no listhesis.pdf
• Results - SS with Spondylolisthesis
• Intention to treat analysis – no difference
• As treated analysis – Surgery better than non op at 2 year and 4 year
• SPORT with listhesis.pdf
• Results for discectomy
• High cross over - 50% of those to surgery did not have surgery, 30% of non op received surgery
• ITT analysis - no difference
• ATT - Surgery greater improvement in outcome measures for 4 and 8 years
• Criticisms of SPORT trial
• No consistent surgical mx as it can be decompression alone, + fusion or even instrumentation (for spondylolisthesis)
• No specific protocol for non Op mx
• Very high cross over rates. Only 33% randomized to op underwent op; 43% randomized to non-op underwent op!
• High drop out rate with only 64% remaining at 8 year mark

• No consensus in literature. No role for routine fusion unless presence of spondylolisthesis
• For fusion: Ghogawala NEJM RCT of 66 patients with stable grade 1 spondylolisthesis. Re-operation for fusion was 14% vs 34%. but no significant improvement in function. Higher cost and longer surgery
• Not for Fusion: Peter Forsth et al. 247 patients stratified randomized with or without presence of spondylolisthesis. Found that with or without spondylolisthesis, fusion did not result in better clinical outcomes at 2 or 5 years.
• In my practice, I will
• Fuse when presence of dynamic instability (flex extend views, facet fluid) or axial back pain present
• OR iatrogenic decompression resulting in instability (complete laminectomy OR excision > 50% of facet joints)

• 5 categories and 8 non organic tests
• Categories - tenderness, simulation, distration, regional disturbance, over-reaction

Canon of DORTS D - distraction - SLR in sitting/ standing is different O - over reaction - facial expression R - Regional - non dermatomal sensory loss or patchy weakness T - tender - even skin S - stimulated - axial load head, rotation

• 3 or more signs = non organic back pain but DOES NOT equate to malingering
• Should do more comprehensive testing

• Diagnostic test; Radio-opaque dye injected into disc under fluoroscopic guidance
• In normal disc, dye remains in nucelus and appears as a 'cotton ball'
• In a herniated disc, dye outlines the fissue to or through the outer annulus
• Diffusely degenerated disc - contrast spreads throughout the disc and disc space may appear narrow on lateral radiography

• This can then be supplemented with a post procedure CT (CT discography)

‣

Classify CT discography based on the Dallas Discogram Description

• Grade 0 = contrast agent within normal nucleus pulposus
• Grade 1 = agent extend radially along fissue involving inner 1/3 of AF
• Grade 2 = agent extend to middle 1/3 of AF
• Grade 3 = agent extent into outer 1/3 of AF
• Grade 4 = grade 3 with involvement of more than 30 ° of disc circumference

• 5 criteria Based on the Spine Intervention Society (SIS) guidelines
• 1. Pain must be similar or exactly like the patient's clinical pain "Concordance"
• 2. Volume limit of 3ml contrast
• 3. Pressurization no greater than 50 psi above opening pressure
• 4. Adjacent discs act as controls - painless or non concordant pain
• 5. Radiographic image of disc must be abnormal from another source.
• https://academic.oup.com/painmedicine/article/19/1/3/3074755

• It is an invasive procedure
• Short term risks - discitis, acute disc herniation
• Long term risks - some studies show higher rate of lumbar disc degeneration
• Risk of post procedure discitis

• Back pain caused by lumbosacral transtional vertebrae (LSTV)
• Lumbarised S1 or Sacralized L5!

• Castellvi Classification