Peripheral Mononeuropathy - Lumbar Plexus

Question 1

Where is the Lumbar Plexus found?

Answer 1

Within the substance of the Psoas Major Muscle and Anterior to Transverse Processes of the Lumbar Vertebrae.

Question 2

Spinal Nerves of the Lumbar Plexus.

Answer 2

L1-L4 : Anterior Rami.

Question 3

Nerve Branches of the Lumbar Plexus.

Answer 3

1. Iliohypogastric Nerve.
2. Ilioinguinal Nerve.
3. Genitofemoral Nerve.
4. Lateral Cutaneous Nerve of the Thigh.
5. Obturator Nerve.
6. Femoral Nerve.

Question 4

What is a Lumbosacral Plexopathy?

Answer 4

A disorder affecting the lumbar or sacral plexus of nerves - caused by damage to the nerve bundles.

Question 5

When is a Plexopathy suspected?

Answer 5

If symptoms cannot be localised to a single nerve e.g. neuropathic pains, numbness, weakness, wasting.

Question 6

Aetiology of Lumbosacral Plexopathy.

Answer 6

1. Diabetic Amyotrophy - Lumbosacral Radioplexus Neurophagy.
2. Idiopathic (like Parsonage-Turner of Brachial Plexus).
3. Tumour Compression.