Facet Injections and Ablation: They can Work! Let me Tell You How - PowerPoint PPT Presentation

Facet Injections and Ablation: They can Work! Let me Tell You How COLIN B. HARRIS, MD ASSISTANT PROFESSOR DEPARTMENT OF ORTHOPAEDICS RUTGERS – NEW JERSEY MEDICAL SCHOOL NEWARK, NJ

Disclosures • Consulting – Globus, Inc.

Background • Lumbar central canal stenosis common in patients >65 yrs of age • Clinical syndrome of low back pain (LBP) +/- • Radiculopathy • Neurogenic claudication • Conservative treatment • NSAID’s • Physical Therapy

Treatment algorithm • Epidural • Laminectomy • NSAID’s • Facet injection • Fusion Conservative Injections Surgery • Physical • Medial branch • Interspinous Therapy blocks device

“Three Joint Complex” • Spinal motion segment • Intervertebral disc + 2 paired facet (zygaphophyseal) joints • Disc degeneration -> micro- instability -> facet degeneration • Late stabilization (osteophytes) Kirkaldy-Willis, Farfan Clin Orthop 1982

Anatomy of Facet • Superior articular process “SAP” (dorsomedial) • Inferior articular process “IAP” (ventrolateral) • Capsule • 1 mm thick • Attaches 2 mm from articular surface SAP • Innervation: two medial branches of dorsal primary ramus and level above (MBB) IAP

“Facet Syndrome” • Sagittally oriented in lumbar spine • Unlike disc -> restricts rotatory motion, allows flexion and extension • Protects disc from excessive shear / torsional strain • Disc degen -> load shifts posteriorly to facets • Aging • Micro-instability • Often accompanies spinal stenosis

CT Grading of Facet Degeneration

Types of Facet Injections • Intra-articular blocks • Medial branch blocks • Radiofrequency ablation (RFA)

Intra-articular injections • Mooney and Robertson 1976 • Target joint capsule • Anesthetic of known half-life -> Diagnostic block • <50% maintain response over 3-6 months • Lowest level of evidence but commonly performed Mooney V, Robertson J. Clin Orthop 1976;115:149-57.

Protocol • Facets postulated as pain generator • Controlled, diagnostic block with arthrogram • Zygapophyseal pain likely if 100% relief Varlotta G, et al. Skeletal Radiol 2011;40:149-157

Medial branch blocks “MBB” • Innervation to joint directly targeted • Significant improvements in pain reported at 3,6, 9 and 12 months (Manchikanti et al 2007) • Pain fibers inhibited by anesthetic alone (steroids not critical) • Risk of complications low

Medial branch neurotomy (ablation) • Shealy 1974 -> “facet denervation” • Percutaneous coagulation / denervation (RF electrode) • Later found to be anatomically flawed • Renamed “Medial Branch Neurotomy” Bogduk et al. 1980 • Nerve proteins denatured-> lasting effect • 60-90% of patients good relief at 9-12 months (Dreyfuss, Gofeld et al.) Bogduk N. Spine J 2008;1:56-64.

• Review of 21 RCT and 5 observational studies (chronic LBP) • At least 50% improvement in pain and functional status = effective • Long-term effectiveness Level II for radiofrequency neurotomy and lumbar facet joint nerve blocks • Level III for lumbar intra-articular injections • Level IV for cervical intra-articular injections

Lumbar facet injections work…

But what about for spinal stenosis?

• Retrospective review (N=42 pts) • Mean age 58 yrs • All patients with central canal stenosis or severe stenosis (Guen grade 3) with a “bleeding diathesis” • 25/42 (59.5%) received effective treatment (median 145 days) • 72% effective (pts with mild stenosis) vs. 41% effective (severe stenosis) • No incidence of bleeding or major complications • Conclusion: FJI are viable and safer alternative to ESI

• Retrospective review (N=73 pts over 1 year period) • All pts underwent facet joint injections (FJI) and epidural steroid injections (ESI) for lumbar central stenosis • Mean age 69.7 yrs, 66% received FJI as 3 rd injection (patient choice) • 13/19 (68%) reported FJI to be effective after initial ineffective ESI • 3/6 (50%) reported ESI to be effective after initial ineffective FCI

Conclusions • Facet injections / MBB can play an important role in chronic LBP and spinal stenosis • Risk of complications is low (vs. ESI) • Diagnostic injections useful prior to starting treatment • Best data is for Medial Branch Neurotomies (vs. intra-articular)

Conclusions • However… • Procedures may be over-utilized -> • High level evidence lacking to make definite recommendation • Surgical decompression still best for neuro deficits, progressive symptoms, severe stenosis

Conclusions • However… • Procedures may be over-utilized -> Must accurately diagnose pain generator • High level evidence lacking to make definite recommendation • Surgical decompression still best for neuro deficits, progressive symptoms, severe stenosis

Thank you!