Common Sources of Referred Pain in the Shoulder Region
Cervical Spine
• Vertebral joints between C3 and C4 or between C4 and C5
• Nerve roots C4 or C5
Referred Pain from Related Tissues
• Dermatome C4 is over the trapezius to the tip of the shoulder.
• Dermatome C5 is over the deltoid region and lateral arm.
• Diaphragm: pain perceived […]

Facet Joint Characteristics
Facet joints are synovial articulations that are enclosed in a capsule and supported by ligaments; they respond to trauma and arthritic changes similar to any peripheral joint.
Various types of meniscoid-like structures or invaginations of the facet capsules are present in the zygapophyseal joints of the spine. They are synovial reflections containing fat and […]

Etiology of Symptoms
The disk is largely aneural; therefore not all disk protrusions are symptomatic.
Pain. Symptoms of pain arise from pressure of a swollen disk or swollen tissues against pain-sensitive structures (ligaments, dura mater, blood vessels around nerve roots) or from the chemical irritants of inflammation if there is herniated disk material.
Neurological signs and symptoms. Neurological […]