A 58-year-old man presents with a 2-year history of bilateral lower limb claudication that worsens with standing and walking, but improves with sitting and forward bending. MRI of the lumbar spine shows degenerative changes with central canal stenosis at L4–L5 and L5–S1 levels. He has normal ankle reflexes and no focal motor deficit. Conservative management with NSAIDs and physical therapy has failed. Which of the following is the most appropriate surgical approach for this patient?

Explanation

## Surgical Management of Lumbar Spinal Stenosis ### Clinical Presentation Recognition **Key Point:** This patient exhibits classic neurogenic claudication (pseudoclaudication)—bilateral leg pain on standing/walking relieved by sitting or forward flexion—which is pathognomonic for lumbar spinal stenosis. ### Imaging Findings - Central canal stenosis at L4–L5 and L5–S1 (degenerative) - No mention of spondylolisthesis or gross instability - Normal reflexes and no motor deficit suggest preserved neurological function ### Surgical Indications & Approach Selection **High-Yield:** The decision between decompression alone (laminectomy) and decompression with fusion hinges on **preoperative instability**. | Feature | Laminectomy Alone | Laminectomy + Fusion | |---------|-------------------|---------------------| | **Indicated when** | Stenosis without instability | Stenosis + spondylolisthesis, segmental kyphosis, or iatrogenic instability risk | | **Instability markers** | None present | Listhesis >3 mm, angular kyphosis, facet hypertrophy >50% | | **This patient** | No preoperative instability documented | — | | **Outcomes** | Adequate for pure stenosis | Fusion adds morbidity without benefit if not needed | ### Why Laminectomy ± Fusion Is Correct **Laminectomy (with selective fusion if intraoperative instability detected)** is the gold standard because: 1. **Decompresses the central canal** directly by removing the hypertrophied ligamentum flavum and lamina 2. **Preserves motion segments** if no instability is present—avoiding fusion-related adjacent-segment disease 3. **Addresses the pathology**: stenosis, not instability 4. **Fusion decision is intraoperative**: if facetectomy >50% or gross instability is found, fusion is added ```mermaid flowchart TD A[Lumbar stenosis + failed conservative Rx]:::outcome --> B{Preoperative instability?}:::decision B -->|No| C[Laminectomy ± selective fusion]:::action B -->|Yes| D[Laminectomy + fusion]:::action C --> E[Decompress canal, preserve motion]:::outcome D --> F[Decompress + stabilize]:::outcome ``` **Clinical Pearl:** Laminectomy alone has 70–80% success rates for pure stenosis without instability. Adding fusion increases operative time, blood loss, and adjacent-segment degeneration risk without improving outcomes in this cohort. ### Why Fusion-First Approaches Are Less Ideal Here - **PLIF/ALIF/LIF** are reserved for stenosis WITH instability, spondylolisthesis, or kyphosis - This patient has **no documented instability**—fusion would be overtreatment - Fusion increases morbidity and pseudarthrosis risk [cite:Rothman & Simeone Spine 6e Ch 42]