Sciatica – Why Back Pain Shoots Down Your Leg – Disc Herniation & Nerve Root Pain

About this video

Sciatica is leg pain that follows the path of a lumbosacral nerve root, most often caused by a lumbar disc herniation pressing on that root. The sensation can feel electric, burning or like a cable being pulled, and it may be sharper far down the leg than at the spine itself. Understanding what the herniated disc actually does to the nerve root explains why the pain travels and how inflammation drives the symptoms. ⏱ Chapters 0:00 Intro 1:18 The Disc 2:27 How A Disc Herniates 3:24 Chemistry, Not Just Compression 4:13 Which Level, Which Root 5:23 Root By Root: Pain, Power, Reflex 6:18 Sensitive To Exclude, Specific To Confirm 7:11 The Red Flags 8:19 What Happens Without Surgery 9:23 The Scan Must Match The Leg 10:14 What Surgery Changes 11:34 Recap & sources This video breaks down the anatomy of a lumbar disc, shows how a herniation develops from bulge to sequestration, and explains why chemical irritation—not just mechanical compression—produces the classic burning sciatica. It maps which disc levels (L4‑L5, L5‑S1) generate specific pain patterns, highlights red‑flag signs that demand urgent review, and outlines what factors truly influence recovery and long‑term outcome. 🦴 IN THIS VIDEO YOU'LL LEARN • How a lumbar disc is structured and why its posterolateral corner is the weak point • The stepwise progression from disc bulge to protrusion, extrusion and sequestration • Why nucleus pulposus triggers an inflammatory response that sensitises the nerve root • Which lumbar levels (L2‑L3, L3‑L4, L4‑L5, L5‑S1) correspond to specific dermatomal pain distributions • How to differentiate true sciatic nerve root pain from referred pain or peripheral neuropathy • Key red‑flag symptoms and signs that suggest infection, tumour or cauda equina syndrome • What clinical examination manoeuvres (straight‑leg raise, crossed‑straight‑leg raise, femoral stretch test) reveal about nerve root involvement • Factors that predict natural resolution of disc herniations and when surgical intervention may be considered 📌 KEY TAKEAWAYS ✔️ Sciatica is a symptom, not a diagnosis; identify the underlying nerve‑root pathology ✔️ Disc herniation causes leg pain mainly through inflammatory mediators released by the nucleus pulposus ✔️ Posterolateral disc herniations at L4‑L5 and L5‑S1 produce the classic sciatica distribution ✔️ A positive straight‑leg raise test reproduces radicular pain and helps localise the affected root ✔️ Most lumbar disc herniations improve with time; surgery is reserved for progressive neurology or intolerable pain despite conservative care 👩‍⚕️ WHO THIS IS FOR This video is designed for orthopaedic trainees, medical students, clinicians managing spinal pain, and interested patients who want a clear, evidence‑based explanation of sciatica and disc herniation. 📚 RELATED TOPICS: lumbar spinal stenosis · cauda equina syndrome · piriformis syndrome · facet joint arthropathy · degenerative disc disease · epidural steroid injection 🔗 More free orthopaedic teaching at Orthovellum.com — subscribe for weekly videos. 🎨 CREDITS • Original Orthovellum production. ⚠️ DISCLAIMER: Educational only — not individual medical advice. Always consult a qualified clinician for diagnosis and treatment. #sciatica #discherniation #nerverootpain #lumbarspine #backpain #radiculopathy #straightlegraise #neurosurgery #orthopaediceducation #spineanatomy #inflammatorypain #treatmentoptions #patienteducation #backhealth