Percutaneous image-guided lumbar decompression (mild)

Percutaneous image-guided lumbar decompression debulks hypertrophied ligamentum flavum through a small posterior port; it suits neurogenic claudication from central stenosis with ligamentum flavum at least 2.5 mm thick, and it outperformed epidural steroids in MiDAS ENCORE.

1. It treats one cause of stenosis. CMS defines PILD as minimally invasive, image-guided debulking of lamina and ligamentum flavum; it does not address disc disease or facet hypertrophy ¹.
2. Candidates meet three criteria. Symptomatic stenosis with neurogenic claudication, stenosis confirmed on imaging, and ligamentum flavum hypertrophy of at least 2.5 mm, typically contributing to 50–85% central canal narrowing ¹.
3. MIST rates it grade A. PILD should be considered for mild-to-moderate stenosis with neurogenic claudication, spondylolisthesis grade 2 or less, and at least 2.5 mm hypertrophy (level 1-A evidence) ¹.
4. Know the contraindications. Absolute: prior spine surgery at the index level and local infection at the site. Relative: spondylolisthesis above grade 2, bleeding disorders and systemic infection ¹.
5. The technique is percutaneous and posterior. With the patient prone and lordosis reduced, a 5.1 mm port allows selective laminotomy with a bone rongeur and ligament debulking with a tissue sculptor under contralateral oblique fluoroscopy ¹.
6. MiDAS ENCORE supports durability. In 274 treated patients (143 PILD, 131 ESI), PILD outperformed epidural steroids at 1 year, and improvement persisted at 2 years with no serious device- or procedure-related events ².

Prior instrumented surgery or laminar disruption at the target level usually leaves no lamina or ligament to debulk, so these patients are not candidates; the evidence base includes two level 1 randomized trials ¹.

• Label indications cover direct decompression from L1 to S1 for symptomatic stenosis ¹.
• The technique has moved from routine epidurograms toward bony landmarks to define the ligamentum flavum ¹.
• PILD began in 2005 as an outpatient option for cancer patients considered too high-risk for open decompression ¹.
• At 2 years, Oswestry Disability Index improved 22.7 points and pain 3.6 points ².
• Zurich Claudication Questionnaire symptom severity and physical function improved by 1.0 and 0.8 points at 2 years ².
• Device- or procedure-related adverse events occurred in 1.3%, and none were serious ².
• Symptomatic stenosis is defined by walking-provoked buttock or leg pain or fatigue with relief from forward flexion, sitting or recumbency ³.
• Coagulopathy should prompt a careful risk-benefit review because of bleeding risk ¹.

• Offering PILD for stenosis caused mainly by disc or facet disease, which it is not designed to treat ¹.
• Treating prior surgery at the index level as only a relative contraindication; it is absolute ¹.
• Mistaking vascular claudication for neurogenic claudication; neurogenic symptoms are relieved by flexion, sitting or lying down ³.