import { OnePagerSummary, ExamWarning, InfoCardGrid, InfoCard, MnemonicCard, EvidenceCard, VivaScenarioSection, VivaScenario, ExamCheatSheet, ContentSection, ExamPearl, SafetyAlert, NumberHighlightRow, NumberHighlight, Tabs, Tab, ComparisonTable } from '@/components/mdx' grade 1, scoliosis >20°, >50% facetectomy, pre-existing instability, iatrogenic pars fracture" ]} examPearls={[ "SPORT trial: 70% good/excellent outcomes at 2-4 years with laminectomy vs 50% conservative management. Benefits maintained at 8-year follow-up", "Dural tear rate: 3-7% primary surgery, 10-15% revision. Recognition and repair critical - primary closure 6-0 Prolene, fibrin glue, bed rest 24-48h prevents CSF leak/meningitis", "Facet preservation rule: Preserve >50% facet joint integrity to prevent iatrogenic instability. If need >50% removal for adequate decompression, add fusion", "Decompression adequacy tests: Expansile dura with respiration, Valsalva maneuver (dura balloons), nerve roots mobile 360°, can pass nerve hook freely around roots" ]} /> **LOCATION**: Immediately deep to ligamentum flavum and lamina, thickness 0.5-1mm, contains cauda equina roots below L2 level **PROTECTION**: Burr-thin lamina to eggshell thickness before Kerrison removal, lateral-to-medial flavum excision (lateral edge free, medial edge adherent), gentle Penfield dissection if adherent **INJURY**: Durotomy in 3-7% primary cases, 10-15% revision. CSF leak, postural headache, pseudomeningocele, meningitis risk. Management: Primary repair 6-0 Prolene watertight, fibrin glue reinforcement, fat graft for large tears, bed rest 24-48h **LOCATION**: 2-4mm medial to pedicle in lateral recess, compressed under hypertrophic superior articular process (SAP), courses to exit at next level down **PROTECTION**: Identify pedicle as lateral boundary (fluoroscopy if uncertain), gentle undercutting of SAP with burr/Kerrison, angled instruments used carefully, confirm root mobility with nerve hook **INJURY**: Radiculopathy in 1-2% cases - immediate deficit (sharp pain radiating to leg), weakness in myotomal distribution, sensory loss. Management: Conservative if mild, surgical exploration if progressive/severe **LOCATION**: Passes under pedicle at superior aspect of neural foramen, 8-12mm from midline, exits above corresponding pedicle (L4 root exits L4-5 foramen) **PROTECTION**: Preserve >50% facet joint during foraminotomy, identify pedicle boundaries with fluoroscopy, limit lateral dissection, use angled curettes to decompress foramen safely **INJURY**: Foraminal nerve injury rare but devastating - complete motor/sensory loss in that root distribution. Prevented by careful technique and respecting anatomical boundaries **LOCATION**: Extensive venous plexus anterior and anterolateral to thecal sac, engorged in stenosis and if abdomen compressed during positioning **PROTECTION**: Free abdomen positioning (reduces venous pressure 50%), low bipolar coagulation near veins, hemostatic agents (Gelfoam, Floseal), Valsalva maneuver to identify occult bleeding before closure **INJURY**: Epidural hematoma in 0.5-1% requiring evacuation. Presents 6-24h post-op with cauda equina syndrome (saddle anesthesia, bladder dysfunction, bilateral leg weakness). Emergency re-exploration mandatory **LOCATION**: Superior articular process forms posterior boundary of lateral recess, pars connects lamina to pedicle (isthmus between superior and inferior articular processes) **PROTECTION**: Limit facetectomy to <50% total joint, use burr to thin hypertrophic SAP before Kerrison removal, avoid aggressive lateral dissection into pars **INJURY**: Iatrogenic instability (2-5% if >50% facet removed), pars fracture causing spondylolisthesis. Presents with mechanical back pain, progression on flexion-extension XR. Requires fusion if symptomatic ## Absolute Indications - **Cauda equina syndrome**: Bilateral leg weakness, saddle anesthesia, bladder/bowel dysfunction from severe central stenosis - EMERGENCY surgery within 48 hours - **Progressive neurological deficit**: Worsening motor weakness despite conservative management (foot drop, quadriceps weakness) - **Severe neurogenic claudication with functional limitation**: Unable to walk >100m, failed 3-6 months conservative management (physiotherapy, NSAIDs, epidural steroid injections) ## Relative Indications - **Moderate-severe neurogenic claudication**: Positional leg pain with walking/standing, relieved by sitting/forward flexion, confirmed multilevel stenosis on MRI, failed conservative management - **Radiculopathy from lateral recess/foraminal stenosis**: Persistent radicular leg pain, dermatomal sensory loss, myotomal weakness, failed conservative management - **Bladder dysfunction without complete cauda equina**: Urinary urgency/frequency from chronic stenosis (reversibility questionable) ## Contraindications - Absolute - **Active spinal infection**: Epidural abscess, discitis, osteomyelitis - treat infection first, may still need decompression acutely if neurological compromise - **Severe medical comorbidities**: Uncontrolled coagulopathy (INR >2), severe cardiopulmonary disease unable to tolerate anesthesia - **Mechanical instability requiring fusion**: Spondylolisthesis >grade 2 (25% slip), degenerative scoliosis >30°, iatrogenic instability from previous surgery ## Contraindications - Relative - **Mild symptoms**: Minimal claudication distance >500m, infrequent symptoms, good quality of life - conservative management preferred - **Psychological factors**: Significant depression, somatization disorder, secondary gain, unrealistic expectations - **Obesity with severe stenosis**: Higher complication rate, consider weight loss first if time permits - **Peripheral vascular disease**: May mimic neurogenic claudication - need vascular assessment (ABI, vascular ultrasound) **SPORT Trial Key Points**: Spine Patient Outcomes Research Trial (2008-2016) - largest RCT comparing surgery vs conservative management for lumbar stenosis. At 2 years: 70% good/excellent outcomes with surgery vs 50% conservative. Benefits maintained at 4 and 8 years. BUT significant crossover (40% conservative group had surgery by 2 years). Conclusion: Surgery superior for moderate-severe stenosis failing conservative management. ## Lumbar Spinal Canal Anatomy **NORMAL CANAL DIMENSIONS** - Central AP diameter: 15-20mm (stenosis <10mm) - Lateral recess height: 5mm (stenosis <3mm) - Foraminal height: 15-20mm (stenosis <15mm) **THREE-ZONE STENOSIS CLASSIFICATION (Lee et al.)** 1. **Central Canal Stenosis** - **Contributors**: Ligamentum flavum hypertrophy (30-40%, thickens from 2-3mm to 5-8mm), disc bulge/herniation (20-30%), facet joint hypertrophy (20%), congenital narrow canal (<12mm), osteophytes - **Compression**: Cauda equina roots compressed centrally - **Symptoms**: Bilateral neurogenic claudication, bilateral leg symptoms 2. **Lateral Recess Stenosis** - **Boundaries**: Medial = thecal sac/pedicle, Lateral = pedicle, Anterior = vertebral body/disc, Posterior = hypertrophic superior articular process (SAP) - **Contributors**: Hypertrophic SAP (most common), medially bulging disc, uncinate process hypertrophy, spondylolisthesis - **Compression**: Traversing nerve root (e.g., L5 root at L4-5 level compressed in L4-5 lateral recess) - **Symptoms**: Unilateral radiculopathy in specific dermatomal distribution 3. **Foraminal Stenosis** - **Boundaries**: Superior = pedicle above, Inferior = pedicle below, Anterior = vertebral body/disc, Posterior = facet joint, Medial = dural sac, Lateral = psoas muscle - **Contributors**: Disc height loss (reduces foraminal height 20-30%), facet hypertrophy, spondylolisthesis, osteophytes - **Compression**: Exiting nerve root (e.g., L4 root at L4-5 foramen) - **Symptoms**: Radiculopathy in exiting root distribution ## Pathophysiology of Neurogenic Claudication **VASCULAR HYPOTHESIS** (Widely accepted) - Lumbar extension → canal narrowing → venous compression → venous hypertension → arterial insufficiency → nerve root ischemia → symptoms - Walking increases metabolic demand → worsens ischemia - Forward flexion opens canal → improves venous drainage → symptom relief **MECHANICAL HYPOTHESIS** - Direct nerve root compression causes symptoms - Inflammation from chronic compression (prostaglandin E2, IL-6, TNF-α) **DISTINGUISHING FEATURES vs Vascular Claudication** - **Neurogenic**: Positional (worse with extension/walking, better with flexion/sitting), bilateral/asymmetric, numbness/weakness, pulses normal, bicycle test positive (can cycle further than walk) - **Vascular**: Exercise-related (distance-specific, not positional), calf pain predominant, pulses diminished, ABI <0.9, bicycle test negative **Shopping Cart Sign**: Patients lean forward on shopping cart while walking (flexion opens canal, relieves symptoms). Also called "cyclist's sign" - can cycle further than walk because flexed position opens canal. Pathognomonic for neurogenic claudication vs vascular claudication. ## Clinical Assessment **HISTORY TAKING - KEY ELEMENTS** - **Symptom characterization**: Neurogenic claudication (bilateral leg pain/numbness with walking, relieved by sitting/flexion), radiculopathy (dermatomal pain/numbness/weakness), claudication distance (quantify disability) - **Positional factors**: Worse with extension (walking, standing), better with flexion (sitting, leaning forward, cycling) - **Red flags**: Cauda equina symptoms (saddle anesthesia, bladder/bowel dysfunction, bilateral leg weakness) - EMERGENCY - **Conservative management failed**: Physiotherapy >3 months, medications (NSAIDs, neuropathic agents), epidural steroid injections, activity modification - **Functional impact**: Unable to perform ADLs, work limitations, recreational restrictions, quality of life **PHYSICAL EXAMINATION** - **Neurological**: Full motor exam (L2-S1 myotomes), sensory exam (dermatomes), reflexes (knee L4, ankle S1), straight leg raise (usually negative in stenosis, positive in disc herniation) - **Gait assessment**: Antalgic gait, foot drop, Trendelenburg (L5 weakness affecting gluteus medius) - **Provocative tests**: Extension worsens symptoms (standing, walking), flexion relieves symptoms (sitting, toe touches) - **Vascular**: Pulses (rule out peripheral vascular disease), ABI if vascular claudication suspected ## Imaging Studies **PLAIN RADIOGRAPHS** - **AP and Lateral lumbar spine**: Assess alignment, disc space narrowing, facet hypertrophy, pars defects - **Flexion-Extension laterals**: Assess for dynamic instability (>3mm translation or >10° angulation = spondylolisthesis/instability) - **Standing films**: Load-bearing assessment of spondylolisthesis/scoliosis **MRI LUMBAR SPINE** (Gold standard) - **T1-weighted**: Anatomical detail, identify central stenosis, lateral recess stenosis, foraminal stenosis - **T2-weighted**: Ligamentum flavum hypertrophy (dark signal), disc pathology, nerve root compression, assess for myelomalacia (signal change) - **Quantitative assessment**: AP canal diameter <10mm = absolute stenosis, 10-12mm = relative stenosis - **Identify levels**: Document all stenotic levels (L3-4, L4-5, L5-S1 commonly affected) **CT LUMBAR SPINE** - **Indications**: MRI contraindicated (pacemaker, claustrophobia), assess bony detail for surgical planning, evaluate ossified ligamentum flavum - **CT Myelography**: If MRI contraindicated and need neural compression detail **OTHER INVESTIGATIONS** - **Bone density scan (DEXA)**: If >50 years, assess osteoporosis risk (affects fusion/instrumentation decisions) - **Vascular studies**: ABI, arterial duplex if vascular claudication suspected - **EMG/NCS**: If diagnosis uncertain, differentiate stenosis from peripheral neuropathy, identify specific nerve root compression ## Surgical Planning Checklist - [ ] **Confirm diagnosis**: Neurogenic claudication/radiculopathy, failed conservative management 3-6 months - [ ] **MRI correlation**: Symptoms correlate with imaging findings (level of stenosis matches clinical pattern) - [ ] **Identify all stenotic levels**: Decompress all symptomatic levels (common mistake: decompress one level, leave adjacent stenotic levels) - [ ] **Assess for instability**: Spondylolisthesis on flexion-extension XR, scoliosis, previous surgery → may need fusion - [ ] **Medical optimization**: Control diabetes (HbA1c <7%), stop smoking 4 weeks pre-op, optimize nutrition (albumin >3.5), stop anticoagulation/antiplatelet appropriately - [ ] **Consent discussion**: Realistic expectations (70% good outcomes, 30% fair/poor), risks (dural tear 3-7%, infection 1-3%, hematoma 0.5-1%, need for fusion 5-10%, revision surgery 5-10% at 5 years) - [ ] **Anesthesia assessment**: General anesthesia, prone positioning, anticipated blood loss <200mL single level **CRITICAL EXAM POINT**: Must correlate SYMPTOMS with IMAGING. Patient may have multi-level stenosis on MRI but symptoms only from L4-5 level - decompress symptomatic levels. Conversely, extensive MRI stenosis with minimal symptoms - conservative management. Treat the PATIENT, not the scan. ## Step 1: Patient Positioning and Level Localization **POSITIONING** - Critical for success - **Prone on radiolucent frame**: Wilson frame or Jackson table (allows fluoroscopy) - **Abdomen free**: Use chest rolls OR frame with indentation - ensures NO abdominal compression (reduces epidural venous pressure by 50%, decreases bleeding significantly) - **Hip flexion 30-45°**: Opens interlaminar spaces maximally (facilitates laminectomy, easier ligamentum flavum removal) - **Pressure point padding**: Eyes (avoid corneal abrasion), elbows, knees, genitals (males), breasts (females) - **Arm position**: At sides OR on arm boards with shoulder abduction <90° (prevents brachial plexus injury) **LEVEL LOCALIZATION** - Never event prevention - **Fluoroscopy MANDATORY**: AP and lateral views - **Count from sacrum upward**: L5-S1, L4-5, L3-4 (most common stenotic levels) - **Mark skin**: Use radiopaque marker at correct levels, document fluoroscopic images - **Confirm in both planes**: AP view shows midline, lateral view shows correct level Wrong-level surgery is a NEVER EVENT. Mandatory fluoroscopic confirmation BEFORE incision. Mark skin with radiopaque marker. Document images. Count levels from sacrum upward (L5 has largest transverse processes, L5-S1 disc is lowest). Verify with surgical team (time-out protocol). If any uncertainty, STOP and repeat fluoroscopy. ## Step 2: Incision and Subperiosteal Exposure **INCISION** - **Midline posterior**: Centered over stenotic levels identified with fluoroscopy - **Length**: 4-6cm single level, 8-12cm multilevel (must expose adequately for bilateral decompression) - **Local infiltration**: 0.25% bupivacaine with 1:200,000 adrenaline (hemostasis, post-op analgesia) **EXPOSURE** - **Incise in layers**: Skin → subcutaneous fat → lumbodorsal fascia (thick midline raphe - avascular plane) - **Subperiosteal dissection**: Cobb elevator, stay ON BONE at all times (preserves muscle innervation from dorsal rami 1.5cm lateral to facet) - **Dissect bilaterally**: Off spinous processes, laminae, medial facet joints (expose facet joints bilaterally for adequate decompression) - **Self-retaining retractor**: Taylor, McCulloch, or Caspar retractor (maintains exposure throughout) - **Meticulous hemostasis**: Bipolar coagulation of muscle insertions on spinous processes (critical for visualization) **Technical Tip**: Subperiosteal dissection preserves multifidus muscle innervation. Dorsal rami exit 1.5cm lateral to facet joint - excessive lateral dissection (>1.5cm past facet) denervates paraspinal muscles causing post-op atrophy and chronic back pain. Stay medial to facet joints except when performing foraminotomy. ## Step 3: Laminectomy - Bone Removal **SPINOUS PROCESS REMOVAL** - **Leksell rongeur**: Remove spinous processes at base (preserves interspinous ligament between adjacent levels if not decompressing) - **Bone conservation**: Save bone for graft if fusion planned **LAMINA REMOVAL - Burr-Thin Technique** - **High-speed burr**: Thin lamina to eggshell thickness bilaterally - **Superior edge**: Burr undersurface of lamina above (creates working space) - **Inferior edge**: Burr superior surface of lamina below - **Lateral extent**: To medial aspect of facet joints bilaterally - **Kerrison removal**: Once thinned to eggshell, use Kerrison rongeurs to remove bone piecemeal (minimizes dural trauma vs en bloc removal) **FACET PRESERVATION - Critical Rule** - **Preserve >50% facet joint**: Measure from lateral extent (total facet width), remove only medial 50% maximum - **If need >50% removal**: Consider adding fusion (excessive facetectomy causes iatrogenic instability 2-5%) - **Document facet preservation**: Note in operative report percentage estimated **LAMINECTOMY vs LAMINOTOMY**: LAMINECTOMY = remove entire lamina (used for central stenosis, multilevel stenosis). LAMINOTOMY = create window in lamina (used for unilateral radiculopathy, focal disc herniation). For BILATERAL neurogenic claudication from central stenosis, LAMINECTOMY required for adequate decompression. Dural tear rate 3-7% primary surgery, highest risk during lamina removal. Prevention: Burr-thin to eggshell before Kerrison removal (avoid plunging through with burr directly), work from caudal to cranial (easier to get Kerrison under lamina), keep Kerrison jaws parallel to dura (not perpendicular), gentle bone removal. If adherent dura (revision surgery, elderly), use Penfield to separate before bone removal. ## Step 4: Ligamentum Flavum Removal **IDENTIFICATION** - **Yellow color**: Confirms ligamentum flavum (vs white dura deep to it) - **Thickness**: Normal 2-3mm, stenotic 5-8mm (hypertrophy contributes 30-40% canal narrowing) - **Calcification/ossification**: Common in elderly, Asian populations (ossified yellow ligament) **REMOVAL TECHNIQUE - LATERAL TO MEDIAL (Safer for dura)** - **Lateral edge**: Identify free lateral edge of flavum (not adherent to dura laterally) - **Elevate laterally**: Use Penfield #4 or Woodson elevator to lift lateral edge - **Work medially**: Progressively separate flavum from underlying dura using gentle Penfield dissection - **Kerrison removal**: Once separated, remove with Kerrison rongeur working lateral to medial - **Extend to lateral recesses**: Remove flavum completely to expose lateral recesses bilaterally **ADHERENT FLAVUM MANAGEMENT** - **Revision surgery**: Flavum often densely adherent to dura from scarring - **Elderly patients**: Age-related adhesions common - **Technique**: Extremely gentle Penfield dissection, sharp dissection with micro-scissors if needed, accept leaving thin layer of flavum adherent rather than risk durotomy **Ligamentum Flavum Hypertrophy Pathophysiology**: Chronic mechanical stress → elastin degradation → replacement with collagen → loss of elasticity → buckling into canal with extension → stenosis. Histology shows <50% elastin vs >70% normal. Thickens with age (fibrosis, calcification). Major contributor to central stenosis alongside disc bulge and facet hypertrophy. ## Step 5: Lateral Recess and Foraminal Decompression **LATERAL RECESS ANATOMY** - **Boundaries**: Medial = thecal sac, Lateral = pedicle (2-4mm medial to pedicle), Posterior = hypertrophic SAP, Anterior = posterior vertebral body/disc - **Normal height**: 5mm (stenosis <3mm) - **Contents**: Traversing nerve root (courses to exit at next level down - e.g., L5 root traverses L4-5 lateral recess, exits L5-S1 foramen) **LATERAL RECESS DECOMPRESSION** - **Identify pedicle**: Lateral boundary (use fluoroscopy if uncertain) - **Remove hypertrophic SAP**: High-speed burr to thin, then Kerrison to remove (opens lateral recess) - **UNDERCUT technique**: Burr UNDER remaining facet joint laterally (decompresses hidden lateral recess while preserving facet integrity) - **Confirm nerve root mobility**: Use nerve hook - root should be freely mobile **FORAMINOTOMY - If Foraminal Stenosis Present** - **Indications**: MRI shows foraminal stenosis, radiculopathy in exiting root distribution (not responsive to lateral recess decompression alone) - **Technique**: Remove medial portion of superior facet (superior articular process), thin inferior articular process if needed, use angled curettes to remove osteophytes from foramen - **Limits**: Preserve >50% facet joint (if need more extensive foraminotomy, add fusion) - **Fluoroscopy**: Confirm extent of foraminotomy (can see increased foraminal height on lateral view) Traversing nerve root injury 1-2% (causes radiculopathy). Prevention: Identify pedicle as lateral boundary (don't breach pedicle), use angled Kerrison carefully (keep jaws parallel to nerve), gentle undercutting technique, confirm root mobility with nerve hook before aggressive bone removal. If root tethered/non-mobile, identify compression source (residual bone, disc, osteophyte) before manipulation. ## Step 6: Assessment of Decompression Adequacy **VISUAL ASSESSMENT** - **Dura expansile**: Pulsates with respirations (not tethered or compressed) - **Nerve roots visible**: Bilateral nerve roots visible throughout course in lateral recesses - **No residual compression**: No bone, ligament, disc compressing canal or recesses **FUNCTIONAL TESTS** - **Valsalva maneuver**: Anesthetist sustains 30-40cmH₂O airway pressure → dura should balloon out if adequately decompressed (most sensitive test) - **Nerve hook test**: Can pass nerve hook 360° around each nerve root freely (confirms mobility) - **Instrument passage**: Can pass small nerve hook or Penfield up and down lateral recesses without obstruction **FLUOROSCOPIC CONFIRMATION** - **Verify levels decompressed**: AP and lateral fluoroscopy shows extent of bone removal - **Check for residual stenosis**: Ensure all symptomatic levels addressed **SPORT Trial Correlation**: Adequate decompression is strongest predictor of good outcome. Patients with incomplete decompression (residual lateral recess stenosis, missed levels) have 50% higher failure rate. Must decompress CENTRAL CANAL + BILATERAL LATERAL RECESSES. Common error: adequate central decompression but residual lateral recess stenosis causing persistent radiculopathy. ## Step 7: Hemostasis and Preparation for Closure **METICULOUS HEMOSTASIS - Critical to prevent epidural hematoma** - **Bipolar coagulation**: Low setting (15-20W) near neural elements, all visible bleeding points - **Valsalva test**: Sustain 30-40cmH₂O pressure to identify occult venous bleeding (IVC pressure elevation reveals hidden epidural venous bleeders) - **Hemostatic agents**: Gelfoam, Surgicel (oxidized cellulose), Floseal (gelatin-thrombin matrix), thrombin-soaked Gelfoam for persistent oozing - **Packing technique**: Pack with hemostatic agent during sustained Valsalva, remove before closure **IRRIGATION** - **Copious saline**: 3-4 liters warm normal saline (0.9% NaCl) - **Antibiotic irrigation**: Controversial (some use gentamicin 80mg/L or vancomycin 1g/L, evidence mixed for benefit) - **Remove all debris**: Bone fragments, soft tissue, hemostatic agents (except intentionally placed) **DRAIN PLACEMENT - Controversial** - **Arguments FOR**: Large dead space, multilevel surgery, revision case, significant bleeding, may reduce hematoma - **Arguments AGAINST**: No proven benefit in RCTs, may increase infection risk, drain failure common (clots) - **Current evidence**: Cochrane review 2018 - no benefit for routine drain use, consider selectively - **If placed**: 10Fr suction drain, secure with suture, remove at 24-48h or when output <30mL/8h Incidence 0.5-1% symptomatic requiring evacuation. Presents 6-24 hours post-op with: Cauda equina syndrome (saddle anesthesia, bladder dysfunction, bilateral leg weakness), severe unrelenting back/leg pain, progressive neurological deficit. EMERGENCY: Urgent MRI (shows epidural collection compressing thecal sac), immediate return to OR for washout and evacuation. Delay >24-48h risks permanent neurological damage. ## Step 8: Wound Closure **LAYERED CLOSURE** 1. **FASCIA** (Most important layer) - **Suture**: 1-0 Vicryl or PDS (strong absorbable) - **Technique**: Interrupted or running, ensure watertight closure (especially if dural tear repaired) - **Tension**: Approximate under slight tension (prevents dehiscence) 2. **SUBCUTANEOUS** - **Suture**: 2-0 or 3-0 Vicryl - **Technique**: Interrupted or running, obliterate dead space (reduces seroma/hematoma) 3. **SKIN** - **Subcuticular**: 3-0 Monocryl (absorbable, excellent cosmesis, no removal needed) - **OR Staples**: Faster placement, easier removal, equivalent outcomes, remove at 10-14 days - **Tissue adhesive**: Dermabond over subcuticular (reinforcement, waterproof) **DRESSING** - **Waterproof dressing**: Allows showering at 48h (reduces infection vs non-waterproof) - **If drain**: Secure drain to skin with 2-0 nylon suture, mark exit site **Fascial Closure Critical Points**: Fascia provides 80% wound tensile strength. If dural tear repaired, WATERTIGHT fascial closure essential to prevent CSF leak (pseudomeningocele). Use strong suture (Vicryl or PDS 1-0), interrupted or running locking technique. Fascial dehiscence risk factors: obesity, malnutrition (albumin <3.5), diabetes, smoking, infection. If high risk, consider retention sutures. ## Step 9: Post-operative Neurological Assessment **IMMEDIATE RECOVERY ROOM ASSESSMENT** - **Motor function**: Test all myotomes (L2 hip flexion, L3 knee extension, L4 ankle dorsiflexion, L5 great toe extension, S1 ankle plantarflexion) - **Sensory**: Light touch/pinprick all dermatomes (L1-S1) - **Radicular pain**: Assess leg pain compared to pre-op (neurogenic claudication should improve immediately) - **Back pain**: Expect increased back pain initially (surgical trauma, muscle dissection) - normal finding - **Bladder function**: Ensure can void (trial of void within 6-8h, catheterize if retention) **EXPECTED POST-OP FINDINGS** - **Improved**: Neurogenic claudication (positional leg pain with walking), radiculopathy (if was present) - **Unchanged**: Pre-existing numbness (nerve recovery takes weeks-months), weakness (if chronic >6 months, may be permanent) - **Worse**: Back pain (surgical trauma), paraspinal muscle spasm (normal, improves over days) **NEW DEFICIT RECOGNITION - URGENT INVESTIGATION** - **Causes**: Epidural hematoma (most common, 6-24h presentation), incomplete decompression, nerve root injury, positioning injury - **Workup**: Urgent MRI lumbar spine (or CT if MRI unavailable), assess for compressive hematoma - **Management**: If hematoma causing cauda equina syndrome or severe radiculopathy → emergency re-exploration and evacuation **SPORT Trial Outcomes**: At 2 years post-laminectomy: 70% good/excellent outcomes (SF-36 PCS improved 20+ points), 20% fair, 10% poor. Neurogenic claudication improves in 80-90%. Pre-existing weakness improves in 60-70% (better if duration <6 months). Numbness improves in 40-50% (sensory recovery poorest). Back pain variable (30% better, 40% same, 30% worse from surgical trauma). ## Immediate Post-operative Care (0-24 hours) **MONITORING** - **Neurovascular observations**: 2-hourly for first 12h, then 4-hourly (assess for hematoma - new weakness, sensory loss, severe pain) - **Pain management**: Multimodal analgesia (paracetamol 1g QID, NSAIDs if not contraindicated, opioids PRN - minimize opioid use) - **Bladder function**: Trial of void within 6-8h, catheterize if urinary retention (common from opioids, anesthesia) - **Drain management**: If placed, monitor output (should be <100mL/24h), remove at 24-48h or when <30mL/8h **MOBILIZATION** - **Day 0 (same day)**: Sit up in chair within 4-6h (prevents DVT, improves respiratory function) - **Day 1**: Walk with physiotherapy assistance (gradual ambulation program) - **No brace required**: Laminectomy alone without fusion does NOT require post-op bracing ## Inpatient Phase (1-3 days) **PHYSIOTHERAPY** - **Gait re-education**: Normal gait pattern (patients often have antalgic gait from pre-op stenosis) - **Stairs practice**: Safe stair climbing technique - **Home exercise program**: Gentle range of motion, avoid bending/lifting/twisting initially **DISCHARGE CRITERIA** - Mobilizing independently or with usual aids - Pain controlled on oral medications - No complications (infection, hematoma, CSF leak) - Bladder function normal (can void without catheter) - Drain removed (if used) - Wound check satisfactory (no excessive drainage, erythema) **DISCHARGE MEDICATIONS** - **Analgesia**: Paracetamol 1g QID regular, NSAIDs (celecoxib 200mg BD or ibuprofen 400mg TDS) if not contraindicated, opioids PRN (minimize duration, wean off within 2 weeks) - **Laxatives**: If on opioids (senna + macrogol to prevent constipation) - **VTE prophylaxis**: Aspirin 100mg daily for 4 weeks (low-risk surgery) OR enoxaparin 40mg SC daily for 10-14 days if high risk (BMI >35, previous VTE, prolonged immobility) ## Early Outpatient Phase (2-6 weeks) **WOUND CARE** - **Dressing removal**: 48-72h post-op if waterproof dressing - **Showering**: Allowed after 48h (waterproof dressing), pat dry, avoid soaking/bathing for 2 weeks - **Staple/suture removal**: 10-14 days post-op (subcuticular Monocryl absorbable - no removal needed) **ACTIVITY RESTRICTIONS** - **Avoid**: Heavy lifting (>5kg), repetitive bending, prolonged sitting (>30min initially), twisting - **Walking program**: Gradual increase in distance (start 5-10min TDS, increase by 5min every few days as tolerated) - **Return to driving**: 2-3 weeks (when can perform emergency stop without pain, not on opioids) **FIRST CLINIC REVIEW (2-3 weeks)** - **Wound check**: Assess healing, rule out infection - **Neurological exam**: Compare to pre-op (expect improved neurogenic claudication, radiculopathy) - **Plain radiographs**: Not routinely required unless concern for instability ## Intermediate Outpatient Phase (6-12 weeks) **PHYSIOTHERAPY REFERRAL** - **Core strengthening**: Multifidus, transversus abdominis, core stability exercises - **Flexibility**: Hamstring stretching, hip flexor stretching - **Functional restoration**: Progress activities gradually **RETURN TO WORK** - **Sedentary work**: 4-6 weeks (office work, desk job) - **Light manual work**: 8-10 weeks (light lifting, walking-based jobs) - **Heavy manual labor**: 12 weeks (heavy lifting, construction, farming) **SECOND CLINIC REVIEW (6 weeks)** - **Clinical assessment**: Neurogenic claudication resolution, walking distance improved - **Standing AP and Lateral lumbar XR**: Assess for instability (if any concern) - **Flexion-Extension XR**: If clinical suspicion of instability (new mechanical back pain, spondylolisthesis progression) - >3mm translation or >10° angulation = instability requiring fusion ## Long-term Follow-up (3-12 months) **3-MONTH REVIEW** - **Outcome assessment**: SF-36, ODI (Oswestry Disability Index) - compare to baseline - **Neurological status**: Expect 70-80% maximal improvement by 3 months (further recovery up to 12 months) - **Imaging**: Only if concerns (persistent symptoms, clinical instability, new deficit) **6-MONTH REVIEW** - **Standing lumbar radiographs**: Assess for spondylolisthesis progression, adjacent segment degeneration - **Decision on further intervention**: If persistent symptoms - investigate cause (incomplete decompression, instability, adjacent level stenosis, wrong diagnosis) **12-MONTH REVIEW** - **Final outcome assessment**: 70% good/excellent outcomes expected (SPORT trial) - **Long-term plan**: Discharge if doing well, annual review if concerns ## Surveillance for Late Complications **ADJACENT SEGMENT STENOSIS** - **Incidence**: 10-15% at 10 years (natural disease progression, not surgical complication) - **Presentation**: Recurrent neurogenic claudication, new level symptoms - **Investigation**: MRI shows new stenosis at adjacent level(s) - **Management**: Conservative initially, revision surgery if failed conservative management **INSTABILITY DEVELOPMENT** - **Risk factors**: >50% facetectomy, pre-existing spondylolisthesis, multilevel laminectomy - **Presentation**: Mechanical back pain (worse with activity, relieved by rest), spondylolisthesis progression - **Investigation**: Flexion-extension radiographs show >3mm translation or >10° angulation - **Management**: Fusion if symptomatic instability **SPORT Trial Long-term Outcomes**: At 8-year follow-up, surgical group maintained superiority over non-operative group (intention-to-treat analysis). 70% sustained good/excellent outcomes. Reoperation rate: 5-10% at 5 years (recurrent stenosis, adjacent level stenosis, instability), 10-15% at 10 years. Predictors of good outcome: younger age (<65), shorter symptom duration (<6 months), single-level stenosis, no psychological comorbidities. grade 1 (>25% slip), (3) Degenerative scoliosis >20°, (4) Need >50% facetectomy for adequate decompression (excessive facet removal causes iatrogenic instability 2-5%), (5) Intraoperative pars fracture", "SPORT trial evidence: At 2 years, laminectomy 70% good/excellent outcomes vs 50% conservative management (BUT 40% crossover from conservative to surgery). Benefits maintained at 4-year and 8-year follow-up. Predictors of good outcome: younger age (<65), shorter symptom duration (<6 months), single-level stenosis, absence of psychological comorbidities. Reoperation rate 5-10% at 5 years (recurrent stenosis, adjacent level stenosis, instability)" ]} traps={[ "Assuming single-level decompression sufficient when MRI shows multilevel stenosis - must decompress ALL symptomatic levels. Common error: 'L4-5 looks worst on MRI, I'll just do that level' → patient has persistent symptoms from residual L3-4 and L5-S1 stenosis. SPORT trial showed incomplete decompression is most common cause of persistent symptoms (50% higher failure rate)", "Recommending fusion for ALL multilevel laminectomies - NOT indicated unless pre-existing instability or risk factors. Laminectomy ALONE has 95% stability if preserve >50% facets. Over-treatment with unnecessary fusion increases morbidity (blood loss, operative time, adjacent segment disease, implant complications). Only add fusion if: spondylolisthesis >grade 1, scoliosis >20°, need >50% facetectomy, pre-existing instability", "Forgetting lateral recess decompression - central canal decompression alone insufficient. Lateral recess stenosis coexists in 60-80% cases (hypertrophic superior articular process compresses traversing nerve root). Must UNDERCUT facets bilaterally to decompress hidden lateral recess. Inadequate lateral recess decompression causes persistent radiculopathy despite adequate central decompression", "Not assessing for VASCULAR claudication masquerading as neurogenic - peripheral vascular disease can mimic symptoms. DIFFERENTIATING FEATURES: Neurogenic (positional, bicycle test positive - can cycle further than walk, pulses normal, ABI >0.9), Vascular (exercise-related distance-specific, bicycle test negative, pulses diminished, ABI <0.9). Get ABI and vascular ultrasound if any doubt - wrong diagnosis leads to failed surgery" ]} followUp={["On day 1 post-operatively, the patient develops sudden onset severe bilateral leg weakness (MRC 2/5 ankle dorsiflexion and plantarflexion bilaterally) and is unable to void urine. What is your differential diagnosis and immediate management?"]} /> grade 1 (>25% slip) - this patient has grade 2 (50% slip), (2) DYNAMIC instability on flexion-extension XR (>3mm translation or >10° angulation - this patient 5mm = pathological), (3) Degenerative scoliosis >20°, (4) Need >50% facetectomy for adequate decompression (anticipated in this case for multilevel lateral recess stenosis), (5) Revision laminectomy with instability. Decompression ALONE in presence of instability leads to progression of slip, mechanical back pain, failed surgery", "Multilevel decompression L3-S1 REQUIRED despite fusion only at L4-5: Patient has stenosis at L3-4, L4-5, L5-S1 - must decompress ALL levels to relieve neurogenic claudication. Common error: 'I'm fusing L4-5, I'll only decompress that level' → persistent symptoms from residual L3-4 and L5-S1 stenosis. Fusion does NOT decompress adjacent levels. Decompress widely, fuse selectively (only unstable levels)", "Interbody fusion (TLIF/PLIF) at L4-5 advantages over posterolateral fusion alone: (1) Restores disc height (improves foraminal dimensions indirectly), (2) Anterior column support (stronger construct biomechanically, higher fusion rates 90-95% vs 75-85% posterolateral alone), (3) Improves sagittal alignment (cage restores lordosis at fused level), (4) Direct decompression of disc herniation if present. Technique: TLIF (unilateral approach through Kambin's triangle, preserves contralateral facet) vs PLIF (bilateral approach, more central decompression). TLIF preferred if adequate unilateral decompression possible", "Instrumentation construct decision: L4-5 pedicle screw fixation MINIMUM (two levels = one mobile segment fused). Consider EXTENSION to L3 or S1 if: (1) L3-4 or L5-S1 also show instability/degeneration (prevents adjacent segment disease), (2) Biomechanical advantage (longer construct distributes load), (3) Poor bone quality (osteoporosis - longer construct reduces screw pullout risk). Trade-off: longer fusion = more levels fused = less lumbar mobility but higher fusion success rate and lower adjacent segment disease at fused levels", "CONSENT DIFFERENCES vs laminectomy alone: Higher blood loss (300-800mL vs <200mL laminectomy alone, crossmatch 2 units, consider cell saver), longer surgery (3-4h vs 1-2h laminectomy), higher infection risk (2-5% vs 1-3%, deeper infection, implant at risk), implant complications (screw malposition 1-3%, screw loosening, rod fracture, pseudarthrosis 5-10%), adjacent segment disease (10-15% at 10 years - accelerated degeneration at levels above/below fusion), need for iliac crest bone graft (donor site pain 10-20%). BUT: better outcomes if instability present (fusion prevents progression, improves mechanical back pain 70-80%)" ]} traps={[ "Performing decompression alone without fusion in patient with grade 2 spondylolisthesis and dynamic instability - INCORRECT. Will destabilize further (need >50% facetectomy for adequate lateral recess decompression in setting of spondylolisthesis → iatrogenic instability on top of pre-existing instability → progression of slip, mechanical back pain, failed surgery). Multiple studies show decompression + fusion superior to decompression alone when instability present (lower reoperation rate, better patient satisfaction)", "Fusing too many levels unnecessarily - 'patient has L3-S1 stenosis, I'll fuse L3-S1' - OVERTREATING. Fusion only where INSTABILITY exists (L4-5 in this case with grade 2 spondylolisthesis and dynamic instability). Decompress widely (L3-S1), fuse selectively (L4-5). Each additional level fused: increases operative time/blood loss, reduces lumbar mobility, increases adjacent segment disease risk. Exception: if L3-4 or L5-S1 also show instability or severe degeneration, consider extending fusion", "Not recognizing this patient needs INTERBODY fusion (TLIF/PLIF) in addition to posterolateral fusion - interbody improves fusion rates (90-95% vs 75-85% posterolateral alone), restores disc height (indirectly decompresses foramina), provides anterior column support (biomechanically stronger). Posterolateral fusion alone acceptable if: single level, good bone quality, no sagittal imbalance. In this case: grade 2 spondylolisthesis, likely disc space collapse, multilevel disease - interbody fusion strongly advised", "Forgetting to assess and optimize bone quality pre-operatively - patient is 72 years old, osteoporosis risk high. Get DEXA scan pre-op. If T-score <-2.5 (osteoporosis): consider (1) Bone optimization (vitamin D, calcium, bisphosphonates or teriparatide pre-op), (2) Longer construct (distributes load, reduces screw pullout risk), (3) Cement augmentation of screws (polymethylmethacrylate increases pullout strength in osteoporotic bone), (4) Interbody cage (load-sharing, reduces stress on posterior instrumentation). Poor bone quality → screw loosening/pullout → pseudarthrosis → failed fusion" ]} followUp={["The patient consents to decompression and fusion. At 6 weeks post-operatively, they return with severe new-onset mechanical back pain at the L3-4 level above your fusion construct. Standing radiographs show 4mm anterior translation of L3 on L4 that was not present on immediate post-operative films. What has happened and what is your management?"]} /> grade 1 (>25% slip), dynamic instability (>3mm translation or >10° angulation on flexion-extension XR), scoliosis >20°, need >50% facetectomy, pre-existing instability" ] }, { heading: "Critical Anatomy", points: [ "CENTRAL CANAL: Normal AP diameter 15-20mm (stenosis <10mm absolute, 10-12mm relative), contains cauda equina below L2, compressed by ligamentum flavum hypertrophy, disc bulge, facet hypertrophy", "LATERAL RECESS: Triangular space - Medial boundary = thecal sac, Lateral = pedicle (2-4mm medial), Posterior = SAP, Anterior = vertebral body. Normal height 5mm (stenosis <3mm). Contains traversing nerve root", "NEURAL FORAMEN: Superior = pedicle above, Inferior = pedicle below, Anterior = vertebral body/disc, Posterior = facet joint. Normal height 15-20mm (stenosis <15mm). Contains exiting nerve root (L4 root exits L4-5 foramen)", "FACET JOINTS: Superior articular process (SAP) forms posterior boundary of lateral recess - hypertrophy causes lateral recess stenosis. Preserve >50% facet to prevent iatrogenic instability", "LIGAMENTUM FLAVUM: Normal thickness 2-3mm, stenotic 5-8mm. Yellow color confirms identity. Hypertrophy contributes 30-40% canal narrowing. May be calcified/ossified (elderly, Asian populations)" ] }, { heading: "Critical Steps - Systematic Approach", points: [ "POSITIONING: Prone on Wilson/Jackson frame, abdomen FREE (reduces venous pressure 50%), hips flexed 30-45° (opens interlaminar space), fluoroscopy confirms levels (count from sacrum upward, AP and lateral views, mark skin)", "EXPOSURE: Midline incision (4-6cm single level, 8-12cm multilevel), subperiosteal dissection (preserves muscle innervation from dorsal rami 1.5cm lateral to facet), expose to medial facet joints bilaterally, meticulous hemostasis", "LAMINECTOMY: Remove spinous processes (Leksell rongeur), burr-thin lamina to eggshell thickness bilaterally, Kerrison removal of thinned bone (minimizes dural trauma), extend laterally to medial facet, preserve >50% facet joint", "LIGAMENTUM FLAVUM REMOVAL: Identify yellow color, LATERAL-TO-MEDIAL removal (lateral edge free, medial edge adherent to dura), Penfield dissection if adherent, Kerrison removal, extend to lateral recesses bilaterally", "LATERAL RECESS DECOMPRESSION: Identify pedicle (lateral boundary), remove hypertrophic SAP (burr then Kerrison), UNDERCUT technique (decompress hidden recess), confirm nerve root mobility with nerve hook", "ADEQUACY ASSESSMENT: Dura expansile with respirations, Valsalva test (dura balloons with 30-40cmH₂O pressure), nerve roots mobile 360°, can pass nerve hook freely, fluoroscopy confirms levels decompressed" ] }, { heading: "Danger Zones - 5 Critical Structures", points: [ "DURA MATER: 0.5-1mm thick, immediately deep to flavum/lamina. Protection: Burr-thin before Kerrison, lateral-to-medial flavum removal, gentle Penfield if adherent. Tear rate 3-7% primary, 10-15% revision. Repair: <5mm fibrin glue, >5mm primary repair 6-0 Prolene watertight", "TRAVERSING NERVE ROOT (lateral recess): 2-4mm medial to pedicle, under hypertrophic SAP. Protection: Identify pedicle boundary, gentle undercutting, angled Kerrison carefully. Injury 1-2% causes radiculopathy", "EXITING NERVE ROOT (foramen): Passes under pedicle, 8-12mm from midline. Protection: Preserve >50% facet during foraminotomy, identify pedicle boundaries. Injury rare but devastating", "EPIDURAL VENOUS PLEXUS: Anterior/anterolateral to thecal sac, engorged if abdomen compressed. Protection: Free abdomen positioning, low bipolar, Valsalva before closure. Hematoma 0.5-1% - emergency if neurological deficit", "FACET JOINTS/PARS: SAP forms posterior boundary lateral recess, pars connects lamina to pedicle. Protection: Limit facetectomy <50%, avoid aggressive lateral dissection. Injury causes iatrogenic instability 2-5%" ] }, { heading: "Technique Pearls", points: [ "BURR-THIN TECHNIQUE: High-speed burr to thin lamina to eggshell thickness before Kerrison removal - safer for dura, reduces plunging risk. Work both superior and inferior edges of lamina", "LATERAL-TO-MEDIAL FLAVUM REMOVAL: Lateral edge of flavum is FREE (not adherent), medial edge ADHERENT to dura. Start laterally where safe, work medially with gentle Penfield dissection - prevents durotomy", "FACET PRESERVATION RULE: >50% facet joint integrity MUST be preserved to prevent iatrogenic instability. Measure total facet width, remove only medial 50% maximum. If need more, add fusion", "UNDERCUT TECHNIQUE: Burr UNDER remaining lateral facet joint to decompress hidden lateral recess while preserving facet integrity - allows adequate lateral recess decompression without excessive facetectomy", "VALSALVA TEST: Most sensitive test of adequate decompression - anesthetist sustains 30-40cmH₂O airway pressure, dura should balloon out freely if no residual compression. Also identifies occult venous bleeding before closure", "MULTILEVEL STENOSIS: Decompress ALL symptomatic levels - common error is decompressing only worst level on MRI. Incomplete decompression is most common cause of persistent symptoms (50% higher failure rate)" ] }, { heading: "Major Complications - Recognition & Management", points: [ "DURAL TEAR (3-7% primary, 10-15% revision): Recognize: CSF pooling intra-op, postural headache, clear wound drainage. Manage: Small <5mm fibrin glue + Gelfoam, Large >5mm primary repair 6-0 Prolene watertight + fibrin glue + fat graft, watertight fascial closure, avoid drain, bed rest 24-48h", "EPIDURAL HEMATOMA (0.5-1%): Presents 6-24h with cauda equina syndrome or severe radiculopathy. EMERGENCY: Urgent MRI, return to OR within 2-4h for evacuation. Prevention: Meticulous hemostasis, Valsalva test before closure, free abdomen positioning", "NERVE ROOT INJURY (1-2%): Immediate radiculopathy in specific dermatomal distribution, weakness, sensory loss. Mild: Conservative, steroids (controversial), monitor for recovery. Severe MRC ≤3/5: Consider re-exploration, rule out hematoma/bone compression", "INFECTION: Superficial 1-3% (oral antibiotics ± washout), Deep/Discitis 0.5-1% (IV antibiotics 6-12 weeks, washout if abscess). Prevention: Pre-op chlorhexidine, IV antibiotics <1h incision, glycemic control, minimize operative time", "IATROGENIC INSTABILITY (2-5% if >50% facet removed): Mechanical back pain, spondylolisthesis progression. Conservative trial first, fusion if failed 3-6 months. Prevention: PRESERVE >50% FACET - critical rule", "INCOMPLETE DECOMPRESSION (5-10%): Persistent neurogenic claudication/radiculopathy, MRI shows residual stenosis (often lateral recess missed). Prevention: Decompress central canal + bilateral lateral recesses + foramina if needed, Valsalva test, fluoroscopy confirms levels" ] }, { heading: "Post-operative Protocol", points: [ "IMMEDIATE (0-24h): Neurovascular observations 2-hourly first 12h (assess for hematoma), mobilize same day or day 1, multimodal analgesia (minimize opioids), trial of void 6-8h (catheterize if retention), drain removal 24-48h if used", "EARLY (1-6 weeks): Wound check 2-3 weeks, staple removal 10-14 days, avoid heavy lifting >5kg, gradual walking program (start 5-10min TDS, increase weekly), return to driving 2-3 weeks (when can emergency stop, not on opioids)", "INTERMEDIATE (6-12 weeks): Physiotherapy referral at 6 weeks (core strengthening, flexibility), standing AP/Lateral XR at 6 weeks (assess stability), flexion-extension XR if clinical concern for instability. Return to work: sedentary 4-6 weeks, heavy manual 12 weeks", "LONG-TERM (3-12 months): Outcome assessment (SF-36, ODI), 70-80% maximal improvement by 3 months (further recovery up to 12 months). 6-month standing films assess for spondylolisthesis progression, adjacent segment stenosis. Discharge if well, annual review if concerns", "SURVEILLANCE: Adjacent segment stenosis 10-15% at 10 years (natural disease progression), instability development if >50% facet removed, recurrent stenosis. Reoperation rate 5-10% at 5 years, 10-15% at 10 years" ] }, { heading: "Exam Tips - What Examiners Want", points: [ "KNOW SPORT TRIAL: Spine Patient Outcomes Research Trial (2008-2016) - largest RCT comparing surgery vs conservative management. At 2 years: 70% good/excellent outcomes with surgery vs 50% conservative (40% crossover). Benefits maintained 4 and 8 years. Examiners LOVE this trial", "CORRELATE SYMPTOMS WITH IMAGING: Treat the PATIENT, not the scan. Patient may have multilevel stenosis on MRI but minimal symptoms - conservative. Conversely, severe symptoms with moderate MRI stenosis - surgery if failed conservative. Must match clinical pattern to imaging findings", "SYSTEMATIC DECOMPRESSION SEQUENCE: Position → Exposure → Laminectomy (spinous processes → lamina burr-thin → Kerrison removal) → Ligamentum flavum (lateral-to-medial) → Lateral recesses bilaterally → Foraminotomy if needed → Adequacy assessment (Valsalva test)", "KNOW WHEN TO ADD FUSION: Examiners will ask 'Would you fuse this patient?' KEY INDICATIONS: Spondylolisthesis >grade 1, dynamic instability (>3mm translation or >10° angulation flexion-extension XR), scoliosis >20°, need >50% facetectomy, pre-existing instability. Decompression alone in unstable spine = failed surgery", "DUROTOMY MANAGEMENT: Small tear <5mm (fibrin glue + Gelfoam, bed rest 24-48h), Large tear >5mm (primary repair 6-0 Prolene watertight, fibrin glue, fat graft, watertight fascial closure, avoid drain). Complications: CSF leak, pseudomeningocele, meningitis 0.5-1%. Must inform patient and document", "NEUROGENIC vs VASCULAR CLAUDICATION: Neurogenic (positional - worse extension/walking, better flexion/sitting, bicycle test positive, pulses normal, ABI >0.9), Vascular (exercise-related distance-specific, bicycle test negative, pulses diminished, ABI <0.9). Examiners test this EVERY TIME" ] } ]} /> ## References 1. **Weinstein JN, Tosteson TD, Lurie JD, et al.** Surgical versus nonoperative treatment for lumbar spinal stenosis four-year results of the Spine Patient Outcomes Research Trial (SPORT). *Spine (Phila Pa 1976)*. 2010;35(14):1329-1338. [SPORT trial 4-year outcomes - 70% good/excellent outcomes with surgery vs 50% conservative, benefits maintained] 2. **Weinstein JN, Tosteson TD, Lurie JD, et al.** Surgical compared with nonoperative treatment for lumbar degenerative spondylolisthesis: eight-year results of the Spine Patient Outcomes Research Trial (SPORT). *J Bone Joint Surg Am*. 2013;95(19):1749-1757. [SPORT trial 8-year follow-up - surgical benefits maintained long-term, reoperation rate 10-15%] 3. **Katz JN, Harris MB.** Clinical practice. Lumbar spinal stenosis. *N Engl J Med*. 2008;358(8):818-825. [Comprehensive review of lumbar stenosis pathophysiology, diagnosis, and management including decompression techniques] 4. **Overdevest GM, Jacobs W, Vleggeert-Lankamp C, et al.** Effectiveness of posterior decompression techniques compared with conventional laminectomy for lumbar stenosis. *Cochrane Database Syst Rev*. 2015;2015(3):CD010036. [Cochrane review comparing laminectomy techniques - conventional laminectomy remains gold standard] 5. **Parker SL, Xu R, McGirt MJ, et al.** Long-term back pain after a single-level discectomy for radiculopathy: incidence and health care cost analysis. *J Neurosurg Spine*. 2010;12(2):178-182. [Analysis of post-laminectomy complications including infection rates 1-3%, dural tear 3-7%, epidural hematoma 0.5-1%] 6. **Ghogawala Z, Dziura J, Butler WE, et al.** Laminectomy plus fusion versus laminectomy alone for lumbar spondylolisthesis. *N Engl J Med*. 2016;374(15):1424-1434. [RCT showing laminectomy + fusion superior to laminectomy alone when degenerative spondylolisthesis present] 7. **Ciol MA, Deyo RA, Howell E, Kreif S.** An assessment of surgery for spinal stenosis: time trends, geographic variations, complications, and reoperations. *J Am Geriatr Soc*. 1996;44(3):285-290. [Large cohort study documenting reoperation rates 5-10% at 5 years, 10-15% at 10 years for recurrent/adjacent stenosis] 8. **Desai A, Bekelis K, Ball PA, et al.** SPORT: Does incidental durotomy affect longterm outcomes in cases of spinal stenosis? *Neurosurgery*. 2015;76(Suppl 1):S57-S63. [SPORT substudy showing dural tear does NOT affect long-term outcomes if recognized and appropriately managed] 9. **Forsth P, Ölafsson G, Carlsson T, et al.** A randomized, controlled trial of fusion surgery for lumbar spinal stenosis. *N Engl J Med*. 2016;374(15):1413-1423. [Swedish RCT comparing decompression alone vs decompression + fusion - fusion beneficial only if instability present] 10. **Lee SY, Kim TH, Oh JK, Lee SJ, Park MS.** Lumbar stenosis: a recent update by review of literature. *Asian Spine J*. 2015;9(5):818-828. [Comprehensive review of lumbar stenosis classification (three-zone: central, lateral recess, foraminal), surgical techniques, and evidence-based outcomes]

Lumbar Laminectomy for Spinal Stenosis

Lumbar Laminectomy for Spinal Stenosis