import { OnePagerSummary, ExamWarning, InfoCardGrid, InfoCard, MnemonicCard, EvidenceCard, VivaScenarioSection, VivaScenario, ExamCheatSheet, ContentSection, ExamPearl, SafetyAlert, NumberHighlightRow, NumberHighlight, Tabs, Tab, ComparisonTable } from '@/components/mdx' **Location**: Within spinal canal, 2-3mm posterior to posterior longitudinal ligament, C5-T1 enlargement most vulnerable. **Protection**: Gentle technique, burr to thin lamina before Kerrison, avoid cord retraction, confirm pulsations **Location**: Foramen transversarium C6-C2, 15-20mm lateral from midline at uncinate process, enters C6 TP foramen. **Protection**: Limit lateral dissection to medial border of lateral mass, stay subperiosteal, avoid >50% facet resection **Location**: Exit above corresponding vertebra (C5 root exits above C5 pedicle), course through foramen 3-5mm from lateral mass. **Protection**: Gentle foraminotomy with 45° Kerrison, undercut medial facet only, visualize nerve root before manipulation **Location**: Surrounds spinal cord and nerve roots, adherent to ligamentum flavum in stenosis, 1mm thick at cervical level. **Protection**: Burr lamina to eggshell, remove ligamentum flavum carefully with pituitary rongeur, primary repair if violated **Location**: Anterior and lateral epidural space, drains to vertebral veins, engorged with prone positioning and stenosis. **Protection**: Meticulous hemostasis with bipolar at low setting, avoid excessive manipulation, use topical hemostatic agents ## Primary Indications **Absolute Indications** - Multilevel cervical myelopathy (3+ levels) with preserved lordosis and posterior cord compression - Ossification of posterior longitudinal ligament (OPLL) with posterior element hypertrophy - Cervical stenosis with congenital narrow canal (developmental diameter <13mm on CT) - Multilevel cervical tumors requiring posterior decompression (e.g., intradural tumors) **Relative Indications** - Multilevel cervical radiculopathy with lateral recess stenosis at 3+ levels - Multilevel facet arthropathy causing foraminal stenosis (combined with foraminotomy) - Recurrent stenosis after anterior procedures at multiple levels - Thoracic myelopathy extending to lower cervical spine ## Contraindications **Absolute Contraindications** - Cervical kyphosis (loss of lordosis mandates anterior approach or combined procedure) - Pre-existing instability or spondylolisthesis without planned fusion - Active cervical spine infection (osteomyelitis, epidural abscess) - Uncorrected coagulopathy or bleeding disorder - Single-level stenosis (anterior cervical discectomy and fusion preferred) **Relative Contraindications** - Previous posterior cervical surgery with scarring (increased dural tear risk) - Severe osteoporosis (consider fusion for stability) - Age <18 years (growing spine, post-laminectomy kyphosis risk higher) - Anterior cord compression predominant (anterior approach more direct) - Patient unable to tolerate prone positioning (cardiopulmonary disease) ## Comparison to Alternative Procedures **Laminectomy vs Laminoplasty** - Laminoplasty preserves posterior elements (hinged opening rather than removal) - Laminoplasty maintains tension band, reduces kyphosis risk (10% vs 30%) - Laminoplasty technically more demanding, significant postoperative neck pain - C5 palsy rate similar (5-10% for both procedures) - Laminoplasty limited by ossified ligamentum flavum or severe kyphosis **Laminectomy vs ACDF (Multilevel)** - ACDF preferred for kyphotic alignment or single/two-level disease - Laminectomy better for 3+ levels with preserved lordosis - ACDF higher pseudarthrosis risk with multilevel constructs (20-30%) - Laminectomy avoids dysphagia, adjacent segment disease of anterior approach - Combined anterior-posterior approach for circumferential compression ## Cervical Spine Posterior Anatomy **Bony Landmarks** - C2 spinous process - most prominent cervical spinous process, bifid - C7 spinous process - vertebra prominens, non-bifid, palpable landmark - Lateral mass - bounded by facet joints, 15-20mm lateral from midline - Foramen transversarium - transmits vertebral artery C6-C2 (V2 segment) - Cervical pedicles - smaller than lumbar, 3-5mm diameter C3-C6 **Soft Tissue Structures** - Ligamentum nuchae - avascular midline raphe from occiput to C7 - Paraspinal muscles - semispinalis cervicis, multifidus, rotatores - Ligamentum flavum - hypertrophies in stenosis (3-5mm vs 2-3mm normal) - Facet joint capsule - critical for stability, preserve >50% - Posterior longitudinal ligament - anterior to spinal cord **Neurovascular Anatomy** - Spinal cord - cervical enlargement C5-T1 (13-14mm diameter) - Cervical nerve roots - exit above corresponding vertebra (C5 exits above C5) - Vertebral artery - V2 segment in foramen transversarium, 15-20mm lateral - Epidural venous plexus - Batson plexus, no valves, engorged with stenosis - Radicular arteries - anterior spinal artery supply, preserve during foraminotomy ## Surgical Approach Details **Positioning** - Prone on Jackson table or chest rolls - Mayfield 3-pin head holder (2 pins frontal 1cm above orbital rim, 1 pin occipital above superior nuchal line) - Alternative: horseshoe headrest (less rigid fixation) - Neck neutral or slight flexion (10-15°) to open interspinous spaces - Avoid excessive flexion causing cord stretch or hypoperfusion **Incision Planning** - Midline posterior incision centered over pathology levels - Extend from C2 spinous process to C7/T1 (11-13cm typical) - Palpate C2 (most prominent cervical spinous) and C7 (vertebra prominens) - Mark incision with marker before draping - Extend inferiorly if lower cervical/upper thoracic levels involved **Exposure Principles** - Subperiosteal dissection minimizes bleeding and muscle damage - Dissect along lamina to lateral mass (15-20mm from midline) - Limit lateral extent to medial border of facet joint - Preserve facet capsule and >50% of articular surface - Self-retaining deep retractors (Taylor, Beckman) under muscles ## Positioning and Preparation (Steps 1-3) ### Step 1: Patient positioning and Mayfield pin placement Patient positioning and Mayfield pin placement: Prone positioning with Mayfield 3-pin head holder (2 pins frontal, 1 pin occipital) or horseshoe headrest. Neck neutral or slight flexion to open interspinous spaces. Avoid excessive flexion causing cord stretch. **Technical Tip**: EXAM KEY: Mayfield pins avoid supraorbital nerve (2cm above orbital rim), temporal vessels, and thin temporal bone. Pin placement 1 finger above pinna, above superior nuchal line posteriorly. Test stability before draping. Frontal pins diverge to avoid frontal sinus. - Supraorbital nerve injury (frontal pins too low) - Temporal artery injury (pins too lateral) - Skull fracture (thin temporal bone, excessive torque) - Spinal cord stretch injury (excessive neck flexion) ### Step 2: Arms tucked, shoulders taped caudally for imaging Arms tucked, shoulders taped caudally for imaging: Arms positioned alongside body with padding at all pressure points. Shoulders taped inferiorly to improve C7-T1 visualization on lateral fluoroscopy. Ensure abdomen free to reduce venous congestion. **Technical Tip**: EXAM KEY: Shoulder taping critical for lower cervical exposure imaging. Check all pressure points: elbows, knees, genitalia in males. Confirm eyes protected and no pressure on globes. Abdomen free reduces epidural venous engorgement and bleeding. - Pressure ulcer (inadequate padding at elbows, knees) - Globe injury (direct pressure on eyes) - Brachial plexus injury (excessive shoulder taping tension) - Compartment syndrome (arms excessively tucked) ### Step 3: Midline posterior incision C2 to C7/T1 Midline posterior incision C2 to C7/T1: Palpate spinous processes to plan incision. C2 most prominent cervical spinous process. C7 is vertebra prominens. Midline incision through skin, subcutaneous tissue, avascular midline raphe of ligamentum nuchae. **Technical Tip**: EXAM KEY: Midline dissection is relatively avascular through ligamentum nuchae. Avoid lateral dissection which encounters paraspinal muscle bleeding. Bovie electrocautery for hemostasis. Inject local anesthetic with epinephrine to skin edges for hemostasis. - Skin necrosis (excessive tension, poor blood supply) - Paraspinal muscle bleeding (lateral deviation from midline) - Wrong level surgery (inadequate palpation of landmarks) ## Exposure (Steps 4-6) ### Step 4: Subperiosteal dissection to lateral masses bilaterally Subperiosteal dissection to lateral masses bilaterally: Sharp subperiosteal dissection with Cobb elevator from spinous process along lamina to lateral mass. Stay on bone to avoid bleeding from paraspinal muscles. Expose lateral to lateral mass (15-20mm from midline). **Technical Tip**: EXAM KEY: Subperiosteal dissection minimizes bleeding and muscle damage. Lateral extent limited by facet joint capsule - preserve capsule for stability. Use monopolar cautery on bone for hemostasis. Periosteal elevator directed laterally along lamina. - Paraspinal muscle bleeding (loss of subperiosteal plane) - Facet capsule violation (dissection too lateral) - Nerve root injury (dissection through foramen) ### Step 5: Self-retaining retractor placement and level confirmation Self-retaining retractor placement and level confirmation: Place deep self-retaining retractors (Taylor or Beckman type) under paraspinal muscles. Obtain lateral fluoroscopy with marker on spinous process to confirm correct surgical levels. Mark levels with marker. **Technical Tip**: EXAM KEY: Wrong-level surgery is never event. Mandatory intraoperative imaging confirmation. Count from C2 (most prominent cervical spinous) or from C7 (vertebra prominens) depending on which more visible. Take fluoroscopy image before any bone removal. - Wrong level surgery (failure to confirm with imaging) - Muscle ischemia (excessive retractor pressure) - Nerve root traction (retractor blade in foramen) ### Step 6: Identify and preserve facet joint capsules Identify and preserve facet joint capsules: Identify facet joints lateral to lamina. Preserve facet capsules and articular cartilage. Violating >50% facet or capsule causes instability requiring fusion. Maintain lateral extent of dissection medial to facet lateral border. **Technical Tip**: EXAM KEY: Facet preservation critical for stability. Post-laminectomy instability occurs if >50% facet resected or capsule violated. If fusion planned, can expose further lateral for screw placement. Mark facet borders with marker to avoid violation during laminectomy. - Facet capsule violation (causes instability) - Inadvertent facetectomy (excessive lateral dissection) - Nerve root injury (foramen violation) ## Decompression (Steps 7-11) ### Step 7: High-speed burr to thin lamina bilaterally High-speed burr to thin lamina bilaterally: Use high-speed burr (matchstick or round diamond burr) to thin lamina bilaterally from medial to lateral. Create bilateral troughs at lamina-facet junction. Thin to eggshell consistency, feel softening and color change to bluish. **Technical Tip**: EXAM KEY: Burr technique safer than rongeur for initial laminectomy. Thin lamina until bluish discoloration visible indicating thinness. Copious irrigation to prevent thermal injury to dura and cord. Start inferiorly, work cephalad. Use 3mm matchstick or 4mm diamond burr. - Thermal injury to dura and spinal cord (inadequate irrigation) - Dural tear (burr penetration if lamina overthinned) - Spinal cord injury (burr penetration through lamina) ### Step 8: Kerrison rongeur to complete laminectomy Kerrison rongeur to complete laminectomy: Use 2-3mm Kerrison rongeur to complete lamina removal. Work from inferior to superior, passing Kerrison under lamina toward spinal cord. Remove spinous process and lamina as single piece if possible. Careful at C2 (cord most vulnerable). **Technical Tip**: EXAM KEY: Kerrison footplate should pass easily under lamina if adequately thinned. If resistance, thin more with burr. Direction of Kerrison jaw opening away from cord. Start at inferior lamina working cephalad. Use 2mm Kerrison at C2 (cord closest to bone). - Spinal cord injury (Kerrison penetration if forced) - Dural tear (Kerrison jaw opening toward dura) - Nerve root injury (lateral Kerrison placement) ### Step 9: Remove ligamentum flavum bilaterally Remove ligamentum flavum bilaterally: Identify thickened, yellow ligamentum flavum. Grasp with small pituitary rongeur and remove carefully. Ligamentum flavum may be hypertrophied in stenosis (3-5mm thick vs normal 2-3mm). Complete removal essential for adequate decompression. **Technical Tip**: EXAM KEY: Ligamentum flavum hypertrophy major contributor to stenosis. Must remove completely for adequate decompression. Attaches to anterior surface of superior lamina and posterior superior margin of inferior lamina. Often adherent to dura in stenosis - sharp dissection required. - Dural tear (ligamentum flavum adherent to dura) - Spinal cord injury (aggressive removal pulling on dura) - Incomplete decompression (residual ligamentum flavum) ### Step 10: Undercutting medial facets for lateral recess decompression Undercutting medial facets for lateral recess decompression: Use Kerrison rongeur or high-speed burr to undercut medial facet bilaterally. Decompress lateral recess without resecting >50% of facet. Identify and protect nerve root in foramen. Visualize dural pulsations. **Technical Tip**: EXAM KEY: Lateral recess stenosis common in multilevel disease. Undercut medial facet with 45-degree angled Kerrison or burr. Preserve >50% facet joint to maintain stability. Foraminotomy if foraminal stenosis present - remove superior articular process medial half. - Nerve root injury (aggressive foraminotomy) - Facet violation (>50% resection causes instability) - Vertebral artery injury (lateral foraminotomy >15mm from midline) ### Step 11: Confirm adequate decompression with visualization and pulsation Confirm adequate decompression with visualization and pulsation: Confirm dura and cord adequately decompressed. Dura should pulsate with respirations. Ensure lateral recess and foramina decompressed bilaterally at all levels. No compression on nerve roots or cord. **Technical Tip**: EXAM KEY: Dural pulsations indicate adequate decompression and no residual compression. Absence of pulsations suggests incomplete decompression or epidural hematoma. Inspect all levels systematically. Nerve hook to palpate nerve roots - should be mobile and soft. - Incomplete decompression (residual stenosis, recurrent symptoms) - False sense of security (pulsations absent may indicate hematoma) ## Closure (Steps 12-15) ### Step 12: Assess stability and consider fusion if indicated Assess stability and consider fusion if indicated: Assess stability based on facet preservation, pre-existing instability, number of levels. If >50% facet resected bilaterally, pre-existing spondylolisthesis, or >3 levels, consider instrumented fusion. Otherwise laminectomy alone. **Technical Tip**: EXAM KEY: Indications for fusion with laminectomy: pre-existing instability, >50% facet resection, kyphotic alignment, >3 contiguous levels (controversial). Fusion adds morbidity but prevents post-laminectomy kyphosis. Lateral mass screws C3-6, pedicle screws C7, rod construct. - Post-laminectomy kyphosis (inadequate fusion in unstable spine) - Unnecessary fusion (adds morbidity if not indicated) ### Step 13: Meticulous hemostasis with bipolar and bone wax Meticulous hemostasis with bipolar and bone wax: Achieve meticulous hemostasis with bipolar cautery on epidural vessels. Apply bone wax sparingly to bleeding bone edges. Consider topical hemostatic agents (Gelfoam, Surgicel) for epidural bleeding. Irrigate thoroughly to remove debris. **Technical Tip**: EXAM KEY: Epidural hematoma risk if inadequate hemostasis. Bipolar cautery at low setting for epidural vessels. Excessive bone wax foreign body reaction risk. Consider epidural drains if significant bleeding. FloSeal or Gelfoam for persistent epidural venous ooze. - Epidural hematoma (inadequate hemostasis) - Thermal injury to dura (excessive bipolar cautery) - Foreign body reaction (excessive bone wax) ### Step 14: Layered closure over suction drain Layered closure over suction drain: Place deep suction drain in epidural space, exit through separate stab incision. Close paraspinal muscles in midline with absorbable suture. Close fascia, subcutaneous layer, and skin. Sterile dressing applied. **Technical Tip**: EXAM KEY: Drain reduces epidural hematoma risk. Remove when output <30ml/24hrs (typically POD 1-2). Paraspinal muscle closure reduces CSF leak if incidental durotomy. Watertight fascial closure essential. Use 0 Vicryl for muscle/fascia, 2-0 Vicryl for subcutaneous, staples or nylon for skin. - Wound dehiscence (inadequate fascial closure) - CSF leak (incidental durotomy not recognized) - Drain malposition (kinked or blocked) ### Step 15: Post-operative neurological assessment and imaging Post-operative neurological assessment and imaging: Immediate post-operative neurological examination documenting motor and sensory function. Compare to preoperative baseline. Early mobilization once awake. Soft collar for comfort (not structural support). Consider post-op CT or MRI if neurological change. **Technical Tip**: EXAM KEY: New neurological deficit post-op requires urgent imaging to exclude hematoma. C5 nerve root palsy occurs in 5-10%, typically transient, mechanism unclear (traction, reperfusion). Most recover spontaneously over weeks-months. EMG at 3 weeks confirms neuropraxia vs axonotmesis. - Missed epidural hematoma (delayed neurological exam) - C5 palsy (deltoid and biceps weakness, usually transient) - Aspiration (altered mental status from anesthesia) ## Specific Complication Management Protocols **C5 Palsy Protocol** 1. Document deltoid and biceps strength postoperatively (usually 3-4/5) 2. EMG/NCS at 3 weeks to confirm neuropraxia vs axonotmesis 3. Physiotherapy for shoulder range of motion and strengthening 4. Reassurance - 80% spontaneous recovery by 6 months 5. Permanent weakness rare (<5%), usually retains 4/5 function **Post-laminectomy Kyphosis Prevention** 1. Careful patient selection - avoid in kyphotic spine 2. Preserve >50% facet joints bilaterally during decompression 3. Consider prophylactic fusion if >3 levels or borderline stability 4. Postoperative soft collar for comfort only (not structural) 5. Surveillance flexion-extension X-rays at 6 weeks, 3 months, 1 year **Dural Tear Management** 1. Recognize intraoperatively - identify tear location 2. Primary repair with 5-0 or 6-0 Prolene suture (running or interrupted) 3. Fibrin glue or DuraSeal sealant over repair 4. Watertight muscle and fascial closure 5. Bed rest 24-48 hours, acetazolamide 500mg BD if persistent leak 6. Revision exploration if pseudomeningocele develops ## Key Evidence and Outcomes Data **Efficacy Studies** - Laminectomy provides significant improvement in JOA score (Japanese Orthopedic Association) from mean 10.5 to 14.2 at 2 years (p<0.001) - 70-80% patients achieve good to excellent outcomes for myelopathy relief - Radiculopathy relief achieved in 85-90% with adequate foraminotomy - Results deteriorate over time - 65% maintain good results at 10 years - Better outcomes if surgery before severe myelopathy (JOA >10) **Comparison to Laminoplasty** - Similar neurological outcomes at 2 years (JOA improvement 3.5 vs 3.8) - Laminoplasty lower kyphosis rate (10% vs 30% for laminectomy alone) - Laminectomy shorter operative time (90 vs 150 minutes) - Laminoplasty higher neck pain scores at 1 year (VAS 4.5 vs 3.2) - No difference in C5 palsy rate (both 5-10%) **Fusion vs No Fusion** - Fusion recommended if >50% facet resected bilaterally - Fusion reduces kyphosis from 30% to <5% - Fusion increases operative time by 60-90 minutes - Adjacent segment disease occurs in 15% at 10 years with fusion - No fusion superior outcomes if facets preserved and lordosis maintained **Australian Context (AOANJRR Data)** - Limited registry data specific to laminectomy (no implants tracked) - Cervical spine surgery infection rate 0.8% nationally - Return to operating room within 30 days for any reason 3.2% - Readmission rate for medical complications 4.5% **Cost-Effectiveness** - Laminectomy alone: $15,000-20,000 AUD (Medicare MBS item 40330) - Laminectomy with fusion: $25,000-35,000 AUD (MBS item 40339 + 40345) - Cost per QALY gained: $18,000-25,000 AUD (cost-effective threshold <$50,000) - Return to work rate 65% at 6 months, 75% at 12 months **Long-term Outcomes** - 10-year reoperation rate 12-18% (kyphosis, adjacent segment disease) - Maintenance of lordosis critical - kyphosis associated with worse outcomes - Quality of life improvement sustained in 70% at 10 years - Progression of myelopathy halted in 85%, improved in 60% ## References 1. Heller JG, Edwards CC, Murakami H, Rodts GE. Laminoplasty versus laminectomy and fusion for multilevel cervical myelopathy: an independent matched cohort analysis. Spine. 2001;26(12):1330-1336. doi:10.1097/00007632-200106150-00009 2. Hashimoto M, Mochizuki M, Aiba A, Okawa A, Hayashi K, Takahashi K. C5 palsy following anterior decompression and spinal fusion for cervical degenerative diseases. Eur Spine J. 2010;19(10):1702-1710. doi:10.1007/s00586-010-1427-5 3. Kaptain GJ, Simmons NE, Replogle RE, Pobereskin L. Incidence and outcome of kyphotic deformity following laminectomy for cervical spondylotic myelopathy. J Neurosurg. 2000;93(2 Suppl):199-204. doi:10.3171/spi.2000.93.2.0199 4. Sani S, Miscusi M, Tropiano P, Tannoury C, Ratliff JK. Biomechanical stability after cervical laminectomy: a review. J Neurosurg Spine. 2011;15(4):351-358. doi:10.3171/2011.5.SPINE10908 5. Fehlings MG, Wilson JR, Kopjar B, et al. Efficacy and safety of surgical decompression in patients with cervical spondylotic myelopathy: results of the AOSpine North America prospective multi-center study. J Bone Joint Surg Am. 2013;95(18):1651-1658. doi:10.2106/JBJS.L.00589 6. Lee MJ, Bazaz R, Furey CG, Yoo J. Risk factors for C5 palsy after cervical decompressive surgery: a systematic review. Spine. 2013;38(16):1409-1415. doi:10.1097/BRS.0b013e3182a7b73b 7. Matsunaga S, Sakou T, Taketomi E, Komiya S. Clinical course of patients with ossification of the posterior longitudinal ligament: a minimum 10-year cohort study. J Neurosurg. 2004;100(3 Suppl Spine):245-248. doi:10.3171/spi.2004.100.3.0245 8. Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR). Hip, Knee & Shoulder Arthroplasty: 2023 Annual Report. Adelaide: AOA; 2023. Available at: https://aoanjrr.sahmri.com/annual-reports-2023 9. Therapeutic Guidelines Limited. eTG complete [digital]. Melbourne: Therapeutic Guidelines Limited; 2024. Available at: https://www.tg.org.au (Antibiotic prophylaxis for cervical spine surgery) 10. Commonwealth of Australia Department of Health and Aged Care. Medicare Benefits Schedule (MBS) Online. Canberra: Australian Government; 2024. Items 40330 (Laminectomy cervical), 40339 (Posterior cervical fusion), 40345 (Lateral mass screw fixation). Available at: http://www.mbsonline.gov.au

Posterior Cervical Laminectomy

Posterior Cervical Laminectomy