Peripheral Nerve Anatomy
Peripheral nerves serve as the communication lines between the central nervous system and your muscles, skin, and sensory organs.
Core Peripheral Pathways
Median Nerve (Arm & Hand)
Anatomical Path: Originates from the brachial plexus, descends the arm, and passes through the narrow carpal tunnel under the transverse carpal ligament in the wrist.
Clinical Presentation: Compression within the wrist causes classic Carpal Tunnel Syndrome: numbness and tingling in the thumb, index, and middle fingers.
Ulnar Nerve (Arm & Elbow)
Anatomical Path: Originates from the brachial plexus, descends behind the medial epicondyle (the "funny bone" region of the elbow) inside the cubital tunnel.
Clinical Presentation: Compression at the elbow leads to Cubital Tunnel Syndrome: sensory loss and tingling in the ring and little fingers, sometimes with hand weakness.
Sciatic Nerve (Pelvis & Leg)
Anatomical Path: The largest single nerve in the human body. Formed by lumbar and sacral nerve roots, exiting the pelvis and descending down the back of each leg.
Clinical Presentation: Compression from a herniated lumbar disc or piriformis muscle causes Sciatica: sharp, shooting pain radiating down the back of the thigh and leg.
Biomechanical Entrapment Concepts
Nerve compression can occur at narrow anatomical tunnels or due to mechanical pressure:
- Double-Crush Syndrome: A clinical hypothesis stating that compression of a nerve at one level (e.g. cervical nerve root compression in the neck) makes the nerve significantly more vulnerable to compression at a distal site (e.g. carpal tunnel in the wrist).
- Axonal Transport: Nerves rely on internal cellular transit to supply nutrients along their entire length. Physical compression blocks this transport, leading to localized tissue swelling, numbness, and progressive muscle wasting.
Seek Nerve Compression Assessment
If you are experiencing persistent hand numbness, shooting leg pain, or muscle weakness in your extremities, arrange a clinical review today.